Endangered Species Act
 

Biennial Report to
 

Congress
 

October 1, 1996 - September 30, 1998 

Prepared by: 

U.S. DEPARTMENT OF COMMERCE 

National Oceanic and Atmospheric Administration 

National Marine Fisheries Service 

Office of Protected Resources 
 

Endangered Species Act Biennial Report to Congress 

Table of Contents
 

Introduction .................................................................. 1 
 

Recovery Plans ................................................................ 7 
 

Green Turtle - Atlantic Population .......................................... 8 
 

Green Turtle - Pacific Population .......................................... 10 
 

Green Turtle - East Pacific Population ...................................... 12 
 

Hawksbill Turtle - Atlantic Population ...................................... 14 
 

Hawksbill Turtle - Pacific Population ....................................... 16 
 

Kemp’s ridley Turtle ................................................... 18 
 

Leatherback Turtle - Atlantic Population ..................................... 20 
 

Leatherback Turtle - Pacific Population ..................................... 21 
 

Loggerhead Turtle - Atlantic Population ..................................... 23 
 

Loggerhead Turtle - Pacific Population ...................................... 24 
 

Olive Ridley Turtle - Pacific Population ..................................... 26 
 

Sacramento River Winter-Run Chinook Salmon ............................... 27 
 

Snake River Salmon ..................................................... 29 
 

Gulf Sturgeon .......................................................... 35 
 

Shortnose Sturgeon ..................................................... 37 
 

Status Discussions for Species Listed under the Endangered Species Act of 1973. ....... 38 
 

Green Turtle: Chelonia mydas ............................................ 39 
 

Hawksbill Turtle: Eretmochelys imbricata ................................... 46 
 

Kemp’s Ridley Turtle: Lepidochelys kempii ................................. 52 
 

Leatherback Turtle: Dermochelys coriacea .................................. 55 
 

Loggerhead Turtle: Caretta caretta ......................................... 59 
 

Olive Ridley Turtle: Lepidochelys olivacea ................................... 63 
 

Chinook Salmon: Oncorhynchus tshawytscha ................................. 68 
 

Chum Salmon: Oncorhynchus keta ......................................... 81 
 

Coho Salmon: Oncorhynchus kisutch ....................................... 84 
 

Coastal Cutthroat Trout: Oncorhynchus clarki clarki ........................... 88 
 
 

 

 

Endangered Species Act Biennial Report to Congress 

Sockeye Salmon: Oncorhynchus nerka ..................................... 90 
 

Steelhead Trout: Oncorhynchus mykiss ..................................... 93 
 

Major Threats and Impacts to Pacific Salmonids ............................. 107 
 

Gulf Sturgeon: Acipenser oxyrynchus ...................................... 110 
 

Shortnose Sturgeon: Acipenser brevirostrum ................................ 112 
 

Johnson’s Sea Grass: Halophila Johnsonii .................................. 115 
 

Candidate Species Explanation and Species Status Discussions ..................... 117 
 

Nassau Grouper: Epinephelus striatus ...................................... 119 
 

Warsaw Grouper: Epinephelus Nitrigus .................................... 121 
 

Speckled Hind: Epinephelus drummondhayi ................................. 122 
 

Jewfish: Epinephelus Itajara ............................................ 123 
 

Opossum Pipefish: Microphis brachyurus lineatus ............................ 125 
 

Mangrove Rivulus: Rivulus marmoratus .................................... 127 
 

Atlantic salmon: Salmo salar ............................................. 128 
 

Alabama Shad: Alosa alabamae .......................................... 131 
 

Dusky Shark: Carcharhinus obscurus ...................................... 133 
 

Sand Tiger Shark: Odontaspis taurus ...................................... 137 
 

Night Shark: Carcharhinus signatus ...................................... 140 
 

Key Silverside: Menidia conchorum ....................................... 141 
 

Atlantic Sturgeon: Acipenser oxyrhinchus oxyrhinchus ........................ 142 
 

Saltmarsh Topminnow: Fundulus jenkinsi .................................. 144 
 

White Abalone: Haliotes sorenseni ........................................ 146 
 
Endangered Species Act Biennial Report to Congress 

Introduction
 

The 1978 amendments of the Endangered Species Act of 1973 (ESA) contained a requirement 

that the U.S. Fish and Wildlife Service (FWS) and the National Marine Fisheries Service 

(NMFS) develop and implement recovery plans for species under their jurisdiction. During the 

1988 reauthorization of the ESA, an amendment was added to the ESA requiring the Secretaries 

of Commerce and the Interior to prepare a biennial report “on the status of efforts to develop and 

implement recovery plans for all species listed pursuant to this section and on the status of all 

species for which such plans have been developed.” 

To satisfy this reporting requirement, a summary of recovery efforts for species under NMFS 

jurisdiction for the period October 1, 1996 and September 30, 1998 has been prepared. Included 

in this report is the most current species status and trends information available. Recovery plans 

can be obtained by writing to: 

Endangered Species Division - Recovery Plans 

Office of Protected Resources - F/PR3 

National Marine Fisheries Service 

1315 East-West Highway, 13th Floor 

Silver Spring, MD 20910-3226 

This report is available on-line via the NMFS-Office of Protected Resources Website at: 

http://www.nmfs.noaa.gov/prot_res/readingrm/ESABiennial/98bien.pdf. 

Recovery plans are also available electronically at: 

http://www.nmfs.noaa.gov/prot_res/PR3/recovery.html. 

NMFS manages an information database that tracks: (1) the status of endangered or threatened 

marine species; and (2) the development and implementation of recovery plans to promote 

survival of species. This report was generated from the data in that system. 

The ESA requires development and implementation of recovery plans unless such plans will not 

promote the conservation of the species. Although the ESA does not differentiate between 

domestic and foreign species in this regard, specific management actions are often not feasible 

for species whose range is either totally or primarily outside of U.S. jurisdiction. The range of a 

number of listed marine species is totally outside U.S. jurisdiction. In other cases, the range in 

areas under the jurisdiction of the United States is limited, and management actions in the U.S. 

portion of their range are not likely to contribute to recovery. Therefore, NMFS has focused 

recovery plans to those species primarily under U.S. jurisdiction. 

NMFS believes that local efforts and initiatives are key to restoring environmental health and 

fisheries resources. It is our view that collaboration between Federal, state, tribal, and local 

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Endangered Species Act Biennial Report to Congress 

authorities, and private entities, has the greatest chance of ensuring the recovery of listed species. 

Aggressive initiatives in habitat, hatcheries, and harvest have the potential to restore species to 

levels such that listing under ESA is unwarranted. In perhaps the most complex and 

controversial program ever attempted under the ESA, the Pacific Northwest, under NMFS 

leadership, is moving ahead with significant actions to improve overall environmental health and 

recover listed Pacific salmon and trout. NMFS is also investing substantial funding, technical 

expertise, and policy guidance in support of state, tribal, and local initiatives to restore salmon, 

steelhead, and cutthroat trout populations in California, Oregon, Washington and Idaho. 

Listing Actions occurring during the report period: 

Common Name Population 

Name 

Status Listing Date FR Notice 

Coho Salmon 

Central California Coast Threatened 10/31/1996 61 FR 56138 

Oregon Coast Threatened 8/10/1998 63 FR 42587 

Southern Oregon-Northern 

California 

Threatened 5/6/1997 62 FR 24588 

Steelhead Trout 

California Central Valley Threatened 3/19/1998 63 FR 11346 

Central California Coast Threatened 8/18/1997 62 FR 43937 

Lower Columbia River Threatened 3/19/1998 63 FR 11346 

Snake River Basin Threatened 8/18/1997 62FR 43974 

South Central Coast Threatened 8/18/1997 62 FR 43937 

Southern California Endangered 8/18/1997 62 FR 43937 

Upper Columbia River Endangered 8/18/1997 62 FR 43937 

Johnson’s seagrass Threatened 9/18/1998 63 FR 49035 

Included in this report is information on species proposed for listing under the ESA. During the 

period of this report, the following species were also proposed for listing: 

Common Name Population 

Name 

Status Proposed Rule 

Date 

FR Notice 

Chinook Salmon 

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Endangered Species Act Biennial Report to Congress 

Lower Columbia River Proposed 

Threatened 

3/9/1998 63 FR 11481 

Puget Sound Proposed 

Threatened 

3/9/1998 63 FR 11481 

Upper Columbia River, spring-run Proposed 

Endangered 

3/9/1998 63 FR 11481 

Upper Willamette River Proposed 

Threatened 

3/9/1998 63 FR 11481 

Central Valley California, springrun Proposed 

Endangered 

3/9/1998 63 FR 11481 

Central Valley California, fall/latefall run Proposed 

Threatened 

3/9/1998 63 FR 11481 

Southern Oregon & California 

Coast 

Proposed 

Threatened 

3/9/1998 63 FR 11481 

Snake River fall-run Proposed 

Endangered ­

extension 

3/10/1998 63 FR 11798 

Chum Salmon 

Columbia River Proposed 

Threatened 

3/10/1998 63 FR 11773 

Hood Canal summer-run Proposed 

Threatened 

3/10/1998 63 FR 11773 

Sockeye Salmon 

Ozette Lake Proposed 

Threatened 

3/10/1998 63 FR 11750 

Steelhead Trout 

Middle Columbia River Proposed 

Threatened 

3/10/1998 63 FR 11798 

Upper Willamette River Proposed 

Threatened 

3/10/1998 63 FR 11798 

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Endangered Species Act Biennial Report to Congress 

The following species have also had critical habitat designated or proposed during the reporting 

period: 

Common Name Population Name Designation/ 

Proposal 

Date 

FR Notice CH Status 

Chinook Salmon 

Lower Columbia River 3/9/1998 63 FR 11481 Proposed 

Puget Sound 3/9/1998 63 FR 11481 Proposed 

Upper Columbia River, spring-run 3/9/1998 63 FR 11481 Proposed 

Upper Willamette River 3/9/1998 63 FR 11481 Proposed 

Central Valley California, spring-run 3/9/1998 63 FR 11481 Proposed 

Central Valley California, fall/late-fall run 3/9/1998 63 FR 11481 Proposed 

Southern Oregon & California Coast 3/9/1998 63 FR 11481 Proposed 

Snake River fall-run (range extension) 3/9/1998 63 FR 11481 Designated 

Chum Salmon 

Columbia River 3/9/1998 63 FR 11481 Proposed 

Hood Canal summer-run 3/9/1998 63 FR 11481 Proposed 

Sockeye Salmon 

Ozette Lake 3/9/1998 63 FR 11481 Proposed 

Coho Salmon 

Central California Coast 11/25/1997 62 FR 62741 Proposed 

Southern Oregon-Northern California 

Coast 

11/25/1997 62 FR 62741 Proposed 

Snake River fall-run (range extension) 3/9/1998 63 FR 11481 Proposed 

Green and Hawksbill Turtle 

Culebra, Mona, and Monito Islands, 

Puerto Rico 

9/02/98 63 FR 46693 Designated 

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Endangered Species Act Biennial Report to Congress 

Also included in this report is information on species designated as candidates under the ESA . 

Common Name Area of Concern Designation 

Date 

FR Notice 

Nassau Grouper Atlantic, Caribbean and 

Gulf of Mexico 

6/11/1991 56 FR 26797 

Warsaw Grouper Atlantic and Gulf of 

Mexico 

7/14/1997 62 FR 134 

Speckled Hind Atlantic and Gulf of 

Mexico 

7/14/1997 62 FR 134 

Jewfish Atlantic, Caribbean and 

Gulf of Mexico 

6/11/1991 56 FR 26797 

Opossum Pipefish Eastern Florida 7/14/1997 62 FR 134 

Mangrove Rivulus Eastern Florida 7/14/1997 62 FR 134 

Atlantic Salmon1 Gulf of Maine DPS 12/18/1997 62 FR 66325 

Alabama Shad Gulf of Mexico 7/14/1997 62 FR 134 

Dusky Shark Atlantic, Pacific and Gulf 

of Mexico 

7/14/1997 62 FR 134 

Sand Tiger Shark Atlantic and Gulf of 

Mexico 

7/14/1997 62 FR 134 

Night Shark Atlantic and Caribbean 7/14/1997 62 FR 134 

Key Silverside Florida Keys 6/11/1991 56 FR 26797 

Atlantic Sturgeon Atlantic, anadromous 1988 

Saltmarsh topminnow Gulf of Mexico 7/14/1997 62 FR 134 

White Abalone California 7/14/1997 62 FR 134 

Sockeye Salmon Baker River 3/10/1998 63 FR 11750 

Steelhead Trout Klamath Mountains 

Province 

3/19/1998 63 FR 11346 

Northern California 3/19/1998 63 FR 11346 

Oregon Coast 3/19/1998 63 FR 11346 

1

Previously proposed for listing. Proposal withdrawn in December, 1997 (62 FR 66342). 

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Endangered Species Act Biennial Report to Congress 

 All species currently under NMFS jurisdiction (domestic and foreign), including proposed and 

candidate species, are listed in the Appendix. 

For the sake of efficiency, information on marine mammals is not included in this Biennial 

Report. Detailed information on status and recovery programs for marine mammals is available 

in a separate publication, the Marine Mammal Protection Act of 1972 (MMPA) Annual Report. 

This report is available electronically at: 

http://www.nmfs.noaa.gov/prot_res/PR2/MMPA_Annual_Report/annualreport.html 

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Endangered Species Act Biennial Report to Congress 

Recovery Plans
 

A Sea Turtle Successfully Escapes a Turtle Excluder Device 

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Endangered Species Act Biennial Report to Congress 

PlanTitle: Green Turtle - Atlantic Population
 

Planning Stage: Final 

Plan Approval Date: 10/29/91 

Species Covered 

Common Name Population Name NMFS Status 

Turtle, green Florida Breeding Population Endangered 

Range-wide Threatened 

Plan Status 

NMFS approved and distributed a final recovery plan for green turtles in the Atlantic Ocean in 

1991. 

Recovery Actions 

1.	 Protect and manage nesting habitat. 

a.	 Evaluate current laws on beach armoring, and strengthen laws if necessary. 

b.	 Ensure laws regulating construction and beach armoring are enforced. 

c.	 Acquire in fee-title all undeveloped nesting beaches between Melbourne and 

Wabasso Beach, Florida. 

2.	 Protect and manage populations on nesting beaches. 

a.	 Monitor trends in nesting activity by means of standardized surveys. 

b.	 Evaluate nest success and implement appropriate nest protection measures. 

c.	 Protect and manage populations in the marine environment. 

d.	 Determine seasonal distribution, abundance and status of sea turtles in the 

nearshore marine environment. 

e.	 Determine etiology of sea turtle fibropapillomas and monitor mortality of those 

turtles affected. 

3.	 NMFS has made a major effort to reduce green turtle mortality in shrimp trawl fisheries 

by improving the regulations that require the use of Turtle Excluder Devices (TEDs). 

4.	 NMFS has provided resources for the collection of basic sea turtle biological information. 

5.	 NMFS funded projects are being conducted to determine species composition, relative 

abundance, and seasonal distribution in important nearshore waters of the southeastern 

U.S. Historically, Cedar Key, Florida, supported large numbers of green turtles. 

6.	 NMFS is sponsoring a project to determine distribution and species composition in this 

area. 

7.	 The agency is also conducting research to determine similar information about turtles 

during their pelagic life stages. NMFS laboratories are conducting research on sea turtle 

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Endangered Species Act Biennial Report to Congress 

habitat utilization in the Gulf of Mexico. The project focuses on known sea turtle 

developmental habitats. Analyses of sea turtle strandings have been conducted to monitor 

the level of strandings and possible causes of mortality. 

8.	 Research has been conducted on the effects of pollutants on sea turtles. 

9.	 NMFS is currently conducting research on the etiology and epidemiology of 

fibropapillomas in green turtles from Hawaiian waters and the Atlantic. In addition, 

NMFS is developing an integrated health assessment plan for sea turtles in coastal 

southeastern U.S. waters. 

Recovery Goals 

The Atlantic population of the green turtle in the United States can be delisted if, over a period of 

25 years, the following conditions are met: 

1.	 The level of nesting in Florida has increased to an average of 5000 nests per year for at 

least 6 years; 

2.	 At least 25% (105km) of all available nesting beaches (420km) is in public ownership 

and encompasses greater than 50% of the nesting activity; 

3.	 A reduction in mortality is reflected in higher counts of individuals on foraging grounds; 

and 

4.	 All priority 1 tasks have been successfully implemented. 

Six major actions are needed to achieve recovery: 

1.	 Provide long-term protection to important nesting beaches; 

2.	 Ensure at least 60% success on major nesting beaches; 

3.	 Implement effective lighting ordinances or lighting plans on nesting beaches; 

4.	 Determine distribution and seasonal movements for all life stages in marine environment; 

5.	 Minimize mortality from commercial fisheries; and 

6.	 Reduce threats to population and habitat from marine pollution. 

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Endangered Species Act Biennial Report to Congress 

PlanTitle: Green Turtle - Pacific Population
 

Planning Stage: Final 

Plan Approval Date: 1/12/98 

Species Covered 

Common Name Population Name NMFS Status 

Turtle, green Range-wide Threatened 

Plan Status 

The green turtle is listed as Threatened under the Endangered Species Act (ESA) throughout its 

Pacific Range, except for the Endangered population nesting on the Pacific coast of Mexico 

which is covered under the Recovery Plan for the East Pacific green turtle. In reviewing this 

species’ current status, the Recovery Team found that, outside of Hawaii, the green turtle 

populations have seriously declined and should probably be classified as Endangered. By far, the 

most serious threat to these stocks is from direct take of turtles and eggs, both within U.S. 

jurisdiction and on shared stocks that are killed when they migrate out of U.S. jurisdiction (e.g., 

nesting turtles from American Samoa migrate to Fiji and French Polynesia to feed). In Hawaii, 

green turtle populations appear to have a somewhat less dire status, probably due to effective 

protection at the primary nesting areas of the Northwest Hawaiian Islands and better enforcement 

of regulations prohibiting take of the species. However, the relatively recent increase in the 

incidence of fibropapillomatosis, a disease associated with tumors, in the Hawaiian green turtle 

threatens to eliminate improvements in the status of the stock. Another serious threat to green 

turtle populations throughout the Pacific is associated with increasing human populations and 

development. In particular, human development is having an increasingly serious impact on 

green nesting beaches. 

Significant progress is being made in the monitoring of Hawaiian green turtles by the NMFS and 

the USFWS. A 5-year series of saturation surveys, completed in 1992, led to the development of 

rigorous quantitative methods to estimate the nesting population. Progress is also being made in 

monitoring juvenile and subadult Hawaiian green turtles in their nearshore habitat. 

Recovery Actions 

Actions Needed: Eight major actions are needed to achieve recovery (not in order of priority). 

1.	 All regional stocks that use U.S. waters have been identified to source beaches based on 

reasonable geographic parameters. 

2.	 Each stock must average 5,000 (or a biologically reasonable estimate based on the goal of 

maintaining a stable population in perpetuity) females estimated to nest annually (FENA) 

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Endangered Species Act Biennial Report to Congress 

over six years. 

3.	 Nesting populations at "source beaches" are either stable or increasing over a 25-year 

monitoring period. 

4.	 Existing foraging areas are maintained as healthy environments. 

5.	 Foraging populations are exhibiting statistically significant increases at several key 

foraging grounds within each stock region. 

6.	 All Priority #1 tasks have been implemented. 

7.	 A management plan to maintain sustained populations of turtles is in place. 

8.	 International agreements are in place to protect shared stocks. 

Recovery Goals 

Goal: The recovery goal is to delist the species.
 

Recovery Criteria: To consider de-listing, all of the following criteria must be met:
 

1.	 Stop the direct harvest of green turtles and eggs, through education and law enforcement 

actions. 

2.	 Eliminate the threat of fibropapillomas to green turtle populations. 

3.	 Reduce incidental harvest of green turtles by commercial and artisinal fisheries. 

4.	 Determine population size and status through regular nesting beach and in-water 

censuses. 

5.	 Identify stock home ranges using DNA analysis. 

6.	 Support conservation and biologically viable management of green turtle populations in 

countries that share U.S. green turtle stocks. 

7.	 Eliminate adverse effects of development on green turtle nests and foraging habitats. 

8.	 Control non-native predators of eggs and hatchlings, (e.g., mongoose, feral cats, pigs) in 

the Hawaiian population. 

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Endangered Species Act Biennial Report to Congress 

PlanTitle: Green Turtle - East Pacific Population
 

Planning Stage: Final 

Plan Approval Date: 1/12/98 

Species Covered 

Common Name Population Name NMFS Status 

Turtle, green Mexican Breeding Population Endangered 

Plan Status 

The East Pacific green turtle is listed as Endangered throughout its range. This regionally 

important population of the green turtle (Chelonia mydas although see Taxonomy), has exhibited 

an extreme decline over the last 30 years. This decline was undoubtedly caused by the massive 

overharvest of wintering turtles in the Sea of Cortez between 1950 and 1970, and the intense 

collection of eggs between 1960 and the early 1980s on mainland beaches of Mexico. Primary 

threats to the species in U.S. waters are from entanglement in debris and boat collisions. The 

Primary threat in Mexico is the (illegal) harvest of turtles and eggs. 

Recovery Actions 

1.	 Minimize boat collision mortalities, particularly within San Diego County, California. 

2.	 Minimize incidental mortalities of turtles by commercial fishing operations. 

3.	 Support the efforts of Mexico and the countries of Central America to census and protect 

nesting East Pacific green turtles, their eggs and nesting beaches. 

4.	 Determine population size and status in U.S. waters through regular surveys. 

5.	 Identify stock home range(s) using DNA analysis. 

6.	 Identify and protect primary foraging areas in U.S. jurisdiction. 

Recovery Goals 

1.	 All regional stocks that use U.S. waters have been identified to source beaches based on 

reasonable geographic parameters. 

2.	 Each stock must average 5,000 (or a biologically reasonable estimate based on the goal of 

maintaining a stable population in perpetuity) females estimated to nest annually (FENA) 

over six years. 

3.	 Nesting populations at "source beaches" are either stable or increasing over a 25-year 

monitoring period. 

4.	 Existing foraging areas are maintained as healthy environments. 

5.	 Foraging populations are exhibiting statistically significant increases at several key 

foraging grounds within each stock region. 

6.	 All priority #1 tasks have been implemented. 

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Endangered Species Act Biennial Report to Congress 

7. A management plan to maintain sustained populations of turtles is in place. 

8. International agreements are in place to protect shared stocks. 

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Endangered Species Act Biennial Report to Congress 

PlanTitle: Hawksbill Turtle - Atlantic Population
 

Planning Stage: Final 

Plan Approval Date: 11/24/93 

Species Covered 

Common Name Population Name NMFS Status 

Turtle, hawksbill Range-wide Endangered 

Plan Status 

NMFS approved and distributed a final recovery plan for hawksbill turtles in the Atlantic Ocean
 

in 1993.
 

Recovery Actions
 

The major points outlined in the recovery plan are:
 

1.	 Identify important nesting beaches. 

2.	 Ensure long-term protection of important nesting beaches. 

3.	 Ensure long-term protection of marine habitat. 

4.	 Prevent degradation or destruction of marine habitats from upland erosion and siltation. 

5.	 Prevent degradation of reef habitat from oil, sewage, and other pollutants. 

6.	 Monitor trends in nesting activity. 

7.	 Evaluate nest success and implement nest protection measures. 

8.	 Ensure law enforcement activities prevent poaching on nesting beaches. 

9.	 Determine nesting beach origins for juvenile and adult populations. 

10.	 Quantify threats to adults and juveniles on foraging grounds. 

11.	 Increase law enforcement to reduce poaching in U.S. waters. 

12.	 To eliminate commercial trade in hawksbill turtles, the Secretaries of Commerce and the 

Interior certified Japan under the Pelly Amendment to the Fishermen`s Protective Act of 

1967 for engaging in activities that diminish the effectiveness of CITES. The Pelly 

amendment provides that the President may prohibit the importation of wildlife products 

from the offending country. After negotiations with the U.S. government, Japan 

announced on June 19, 1991, that it would end all trade in hawksbill turtles by the end of 

1992 and withdraw its CITES reservation for hawksbills on July 1, 1994. 

13.	 NMFS is involved with protecting nesting beaches and conducting surveys on primary 

hawksbill nesting areas in the Caribbean. NMFS has also made a major effort to reduce 

hawksbill turtle mortality in shrimp fisheries by implementing regulations requiring the 

use of turtle excluder devices (TEDs). Analyses of sea turtle strandings have been 

conducted to monitor the level of strandings and possible causes of mortality. 

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Endangered Species Act Biennial Report to Congress 

Recovery Goals 

The Atlantic population of the hawksbill turtle in the United States can be delisted, if over a 

period of 23 years, the following goals are met: 

1.	 The adult female population is increasing, as evidenced by a statistically significant trend 

in the annual number of nests five index beaches, including Mona Island and BIRNM. 

2.	 Habitat for at least 50 percent of the nesting activity that occurs in the USVI and Puerto 

Rico is protected in perpetuity. 

3.	 Numbers of adults, subadults, and juveniles are increasing, as evidenced by a statistically 

significant trend on at least five key foraging areas within Puerto Rico, USVI, and 

Florida. 

4.	 All priority one tasks have been successfully implemented. 

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Endangered Species Act Biennial Report to Congress 

PlanTitle: Hawksbill Turtle - Pacific Population
 

Planning Stage: Final 

Plan Approval Date: 1/12/98 

Species Covered 

Common Name Population Name NMFS Status 

Turtle, hawksbill Range-wide Endangered 

Plan Status 

The hawksbill turtle is listed as Endangered throughout its range. In the Pacific, this species is 

rapidly approaching extinction due to a number of factors, but the intentional harvest of the 

species for meat, eggs and the tortoiseshell and stuffed curio trade is of greatest impact. 

Increasing human populations and the concurrent destruction of the habitat are also of major 

concern for the Pacific hawksbill populations. In a review of the status of the species the 

members of Recovery Team (which is made up of biologists with extensive experience in the 

insular Pacific) were surprised and concerned at how few hawksbills are left in areas of oncehigh (or at least much greater) abundance. 

NMFS believed that a lack of regular quantitative surveys of species distribution and population 

status contributed to the Team being previously unaware of how seriously depleted hawksbill 

populations had become in the Pacific. The status of this species is clearly of a highest concern 

for the Pacific and it is recommended that immediate actions be taken to prevent its extinction. 

Recovery Actions 

Eight major actions are needed to achieve recovery (not in order of priority): 

1.	 Stop the direct harvest of hawksbill turtles and eggs, through education and law 

enforcement actions. 

2.	 Reduce incidental mortalities of hawksbills by commercial and artisanal fisheries 

3.	 Determine population size, status and trends through long-term regular nesting beach and 

in-water censuses. 

4.	 Identify stock home ranges using DNA analysis. 

5.	 Support conservation and biologically viable management of hawksbill populations in 

countries that share U.S. hawksbill stocks. 

6.	 Identify and protect primary nesting and foraging areas for the species. 

7.	 Eliminate adverse effects of development on hawksbill nesting and foraging habitats. 

8.	 Control non-native predators of eggs and hatchlings, e.g., mongoose, feral cats, and pigs, 

in the Hawaiian population. 

Recovery Goals 

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Endangered Species Act Biennial Report to Congress 

The recovery goal is to delist the species.
 

Recovery Criteria: To consider de-listing, all of the following criteria must be met:
 

1.	 All regional stocks that use U.S. waters have been identified to source beaches based on 

reasonable geographic parameters. 

2.	 Each stock must average 1,000 females estimated to nest annually (FENA) (or a 

biologically reasonable estimate based on the goal of maintaining a stable population in 

perpetuity) over six years. 

3.	 All females estimated to nest annually (FENA) at "source beaches" are either stable or 

increasing for 25 years. 

4.	 Existing foraging areas are maintained as healthy environments. 

5.	 Foraging populations are exhibiting statistically significant increases at several key 

foraging grounds within each stock region. 

6.	 All Priority #1 tasks have been implemented. 

7.	 A management plan designed to maintain sustained populations of turtles is in place. 

8.	 Ensure formal cooperative relationship with regional sea turtle management programs 

(South Pacific Regional Environment Program [SPREP]). 

9.	 International agreements are in place to protect shared stocks. 

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Endangered Species Act Biennial Report to Congress 

PlanTitle: Kemp’s ridley Turtle
 

Planning Stage: Final 

Plan Approval Date: 8/21/92 

Species Covered 

Common Name Population Name NMFS Status 

Turtle, Kemp's ridley Range-wide Endangered 

Plan Status 

NMFS approved and distributed a final recovery plan for Kemp`s ridley turtles in 1992. 

Significant progress has also been made in collaboration with Mexico and the USFWS to 

establish and maintain more comprehensive nesting beach surveys for Kemp’s ridleys. 

Recovery Actions 

The major points outlined in the recovery plan are: 

1.	 Encourage Mexico to expand and codify the Kemp`s Ridley Natural Reserve at Rancho 

Nuevo. 

2.	 Redefine and codify regulations for better reserve protection. 

3.	 Encourage Mexico to restrict development that may degrade the nesting habitat. 

4.	 Identify important marine habitat. 

5.	 Protect nesting females at Rancho Nuevo. 

6.	 Protect nests and increase hatchling protection at Rancho Nuevo. 

7.	 Monitor population trends at Rancho Nuevo. 

8.	 Determine juvenile and subadult nearshore habitat use. 

9.	 Determine migration routes and foraging areas of adults. 

10.	 Enforce and expand TED regulations. 

11.	 Enforce the trawling prohibitions near Rancho Nuevo. 

12.	 Promote TED use in Mexico. 

NMFS has made a major effort to reduce Kemp`s ridley mortality in shrimp trawl fisheries by 

implementing regulations requiring the use of turtle excluder devices (TEDs). In addition, 

NMFS has provided technical assistance to the Government of Mexico on TED utilization and 

provided funding support for protection of the Kemp’s ridley at the major nesting beach in 

Mexico. 

Projects are being conducted to determine species composition, relative abundance, and seasonal 

distribution in Atlantic and Gulf of Mexico waters. A continuing project to determine 

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Endangered Species Act Biennial Report to Congress 

distribution and species composition is being carried out in the Cedar Key area of Florida`s west 

coast. Historically, this area supported large numbers of Kemp`s ridleys. 

NMFS laboratories are conducting research on sea turtle habitat utilization in the Gulf of 

Mexico. The project focuses on known sea turtle developmental habitats. Kemp`s ridleys are 

tracked with radio and sonic transmitters to determine their temporal and spacial utilization of 

these areas. 

Analyses of sea turtle strandings have been conducted to monitor the level of strandings and 

possible causes of mortality. Physiological research has been conducted on the effects of forced 

submergence on Kemp`s ridleys. 

Recovery Goals 

Because of Kemp's ridleys' aggregated nesting behavior, restricted breeding range, and increasing 

threats from the expanding global human population and general environmental degradation, 

complete recovery (delisting) may not be achievable. Since the principal nesting beach is in 

Mexico, continued, long-term cooperation between the U.S. and Mexico is necessary to recover 

the species. 

The goal of this recovery plan is to upgrade the species from endangered to threatened status. 

Criteria for delisting will be addressed in future revisions of the recovery plan. Criteria for 

upgrading the status are as follows: 

1.	 Continue complete and active protection of the known nesting habitat, and the waters 

adjacent to the nesting beach (concentrating on the Rancho Nuevo area) and continue the 

bi-national protection project. 

2.	 Eliminate mortality from incidental catch in commercial shrimping in the United States 

and Mexico through use of TEDs and achieve full compliance with the regulations 

requiring TED use. 

3.	 Attain a population of at least 10,000 nesting females per year. 

4.	 Successfully implement all priority 1 recovery tasks. 

The major actions necessary for recovery are to: 

1.	 Assist Mexico to ensure long-term protection of the major nesting beach and its environs, 

including the protection of adult breeding stock and enhanced production/survival of 

hatching turtles. 

2.	 Continue TED regulation enforcement in U.S. waters, expanding the areas and 

seasonality of required TED use to reflect the distribution of the species. Encourage and 

assist Mexico to incorporate TEDs in their Gulf of Mexico shrimp fleet. 

3.	 Fill in gaps in knowledge of Kemp`s ridley life history that will result in better 

management decisions. In order to minimize threats and maximize recruitment we 

should: determine distribution and habitat use for all life stages, determine critical 

mating/reproductive behaviors and physiology, determine survivorship and recruitment. 

19
 
 

 

Endangered Species Act Biennial Report to Congress 

PlanTitle: Leatherback Turtle - Atlantic Population
 

Planning Stage: Final 

Plan Approval Date: 4/6/92 

Species Covered 

Common Name Population Name NMFS Status 

Turtle, leatherback Range-wide Endangered 

Plan Status 

NMFS approved and distributed a final recovery plan for leatherback turtles in the Atlantic 

Ocean in 1992. 

Recovery Actions 

The major points outlined in the recovery plan are: 

1.	 Identify and ensure long-term protection of important nesting beaches. 

2.	 Identify important marine habitat. 

3.	 Monitor trends in nesting activity on important nesting beaches with standardized 

surveys. 

4.	 Evaluate nest success and implement appropriate nest protection measures. 

5.	 Implement measures to reduce capture and mortality in the shrimp trawl fishery. 

6.	 Evaluate extent of entanglement in and ingestion of marine debris. 

7.	 Implement and enforce MARPOL. 

8.	 Analyses of sea turtle strandings have been conducted to monitor the levels of strandings 

and possible causes of mortality. 

Recovery Goals 

The goal of the recovery plan is to delist the U.S. population of leatherback turtles. Delisting 

would be considered when the following conditions are met: 

1.	 The adult female population increases over the next 25 years, as evidenced by a 

statistically significant increase in the number of nests at Culebra, Puerto Rico; St. Croix, 

USVI; and along the east coast of Florida. 

2.	 Nesting habitat encompassing at least 75% of nesting activity in the U.S. Virgin Islands, 

Puerto Rico and Florida is in public ownership. 

3.	 All priority 1 tasks have been successfully implemented. 

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Endangered Species Act Biennial Report to Congress 

PlanTitle: Leatherback Turtle - Pacific Population
 

Planning Stage: Final 

Plan Approval Date: 1/12/98 

Species Covered 

Common Name Population Name NMFS Status 

Turtle, leatherback Range-wide Endangered 

Plan Status 

The leatherback turtle is listed as Endangered throughout its range. In the Pacific, leatherback 

populations are in severe decline and recovery actions must be given the highest priority. 

Primary threats to the species are incidental take in coastal and high seas fisheries, and the killing 

of nesting females and collecting of eggs at the nesting beaches. The United States does not have 

any nesting of leatherbacks in its jurisdiction in the Pacific, but has important foraging areas on 

the continental U.S. west coast and near the Hawaiian Islands. It is likely that stocks in U.S. 

waters originate in Mexico and Central America, though some may originate from Southeast 

Asia as well. While not directly classified as a threat, the lack of information on the movement 

patterns and habitat needs of this pelagic species severely hampers recovery efforts and must be 

addressed as a high priority. 

Recovery Actions 

Five major actions are needed to achieve recovery (not in order of priority): 

1.	 Eliminate incidental take of leatherbacks in U.S. and international commercial fisheries. 

2.	 Support the efforts of Mexico and the countries of Central America to census and protect 

nesting leatherbacks, their eggs, and nesting beaches. 

3.	 Determine movement patterns, habitat needs and primary foraging areas for the species 

throughout its range. 

4.	 Determine population size and status in U.S. waters through regular aerial or on-water 

surveys. 

5.	 Identify stock home ranges using DNA analysis. 

Recovery Goals 

The recovery goal is to delist the species. 

Recovery Criteria: To consider de-listing, all of the following criteria must be met: 

1.	 All regional stocks that use U.S. waters have been identified to source beaches based on 

reasonable geographic parameters. 

2.	 Each stock must average 5,000 (or a biologically reasonable estimate based on the goal of 

maintaining a stable population in perpetuity) females estimated to nest annually (FENA) 

over six years. 

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Endangered Species Act Biennial Report to Congress 

3.	 Nesting populations at "source beaches" are either stable or increasing over a 25-year 

monitoring period. 

4.	 Existing foraging areas are maintained as healthy environments. 

5.	 Foraging populations are exhibiting statistically significant increases at several key 

foraging grounds within each stock region. 

6.	 All Priority #1 tasks have been implemented. 

7.	 A management plan designed to maintain sustained populations of turtles is in place. 

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Endangered Species Act Biennial Report to Congress 

PlanTitle: Loggerhead Turtle - Atlantic Population
 

Planning Stage: Final 

Plan Approval Date: 12/26/91 

Species Covered 

Common Name Population Name NMFS Status 

Turtle, loggerhead Range-wide Threatened 

Plan Status 

NMFS approved and distributed a final recovery plan for loggerhead turtles in the Atlantic 

Ocean in 1991. 

Recovery Actions 

The major points outlined in the recovery plan are: 

1.	 Evaluate current laws on beach armoring. 

2.	 Enforce laws regarding coastal construction. 

3.	 Acquire nesting beaches between Melbourne and Wabasso Beach, FL. 

4.	 Monitor trends in nesting activity. 

5.	 Evaluate nest success and implement nest protection measures. 

6.	 Determine seasonal distribution, abundance, population characteristics, and status in 

inshore and nearshore waters. Implement and enforce TED regulations. NMFS has made 

a major effort to reduce loggerhead turtle mortality in shrimp fisheries by implementing 

regulations requiring the use of TEDs. Analyses of sea turtle strandings have been 

conducted to monitor the level of strandings and possible causes of mortality. 

Recovery Goals 

The southeastern United States population of the loggerhead turtle can be delisted if, over a 

period of 20 years, the following conditions are met: 

1.	 The adult female population in Florida is increasing and in North Carolina, South 

Carolina and Georgia, it has returned to prelisting nesting levels (NC = 800 nests/season; 

SC = 10,000 nests per season; GA = 2,000 nests/season). 

2.	 At least 25 percent (560 km) of all available nesting beaches (2240 km) is in public 

ownership, is distributed over the entire nesting range and encompasses greater than 50 

percent of the nesting activity. 

3.	 All priority one tasks have been successfully implemented. 

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Endangered Species Act Biennial Report to Congress 

PlanTitle: Loggerhead Turtle - Pacific Population
 

Planning Stage: Final 

Plan Approval Date: 1/12/98 

Species Covered 

Common Name Population Name NMFS Status 

Turtle, loggerhead Range-wide Threatened 

Plan Status 

The loggerhead turtle is listed as a Threatened species throughout its range. In the Pacific, 

threatened status is consistent with population levels and trends. The stocks found in U.S. 

jurisdiction most likely originate from Japanese nesting areas and thus activities in Japan which 

impact nesting success or foraging turtles in coastal waters are of concern. The United States and 

Mexico (primarily Baja California South) support important developmental habitats for juvenile 

loggerheads. A primary threat to the species in the Pacific is from the incidental mortalities 

associated with commercial fisheries, particularly longline and net fisheries. This threat must be 

minimized for recovery of this species. 

Recovery Actions 

Five primary actions are needed to achieve recovery (not in order of priority): 

1.	 Reduce incidental capture of loggerheads by coastal and high seas commercial fishing 

operations. 

2.	 Establish bilateral agreements with Japan and Mexico to support their efforts to census 

and monitor loggerhead populations and to minimize impacts of coastal development and 

fisheries on loggerhead stocks. 

3.	 Identify stock home ranges using DNA analysis. 

4.	 Determine population size and status (in U.S. jurisdiction) through regular aerial or onwater surveys. 

5.	 Identify and protect primary foraging areas for the species. 

Recovery Goals 

The recovery goal is to delist the species.
 

To consider de-listing, all of the following criteria must be met:
 

1.	 To the best extent possible, reduce the take in international waters (have and enforce 

agreements). 

2.	 All regional stocks that use U.S. waters have been identified to source beaches based on 

reasonable geographic parameters. 

3.	 All females estimated to nest annually (FENA) at "source beaches" are either stable or 

increasing for over 25 years. 

24
 
 

Endangered Species Act Biennial Report to Congress 

4.	 Each stock must average 5,000 FENA (or a biologically reasonable estimate based on the 

goal of maintaining a stable population in perpetuity) over six years. 

5.	 Existing foraging areas are maintained as healthy environments. 

6.	 Foraging populations are exhibiting statistically significant increases at several key 

foraging grounds within each stock region. 

7.	 All Priority #1 tasks have been implemented. 

8.	 A management plan designed to maintain stable or increasing populations of turtles is in 

place. 

9.	 Ensure formal cooperative relationship with a regional sea turtle management program 

(SPREP). 

10.	 International agreements are in place to protect shared stocks (e.g., Mexico and Japan). 

25
 
Endangered Species Act Biennial Report to Congress 

PlanTitle: Olive Ridley Turtle - Pacific Population
 

Planning Stage: Final 

Plan Approval Date: 1/12/98 

Species Covered 

Common Name Population Name NMFS Status 

Turtle, olive ridley Range-wide Threatened 

Mexican Breeding Population Endangered 

Plan Status 

The olive ridley turtle is listed as Threatened in the Pacific, except for the Mexican nesting 

population, which is classified as Endangered. This latter classification was based on the 

extensive over-harvesting of olive ridleys in Mexico, which caused a severe population decline. 

Since the ban on the harvest of turtles in Mexico, the primary threat to the Mexican nesting 

population has been reduced and the population appears to be stabilizing. Downlisting to 

Threatened status may be feasible. The primary threats to the olive ridley appear to be incidental 

take in fisheries and boat collisions while in U.S. waters (or by U.S.-based fishing fleets), and the 

harvest of turtles and eggs on Mexican and Central American nesting beaches. 

Recovery Actions 

Three major actions are needed to achieve recovery (not in order of priority): 

1.	 Minimize incidental mortalities of turtles by commercial fishing operations. 

2.	 Support the efforts of Mexico and the countries of Central America to census and protect 

nesting olive ridleys, their eggs and nesting beaches. 

3.	 Identify stock home ranges using DNA analysis. 

Recovery Goals 

The recovery goal is to delist the species.
 

Recovery Criteria: To consider delisting all of the following recovery criteria must be met:
 

1.	 All regional stocks that use U.S. waters have been identified to source beaches based on 

reasonable geographic parameters. 

2.	 Foraging populations are statistically significantly increasing at several key foraging 

grounds within each stock region. 

3.	 All females estimated to nest annually (FENA) at "source beaches" are either stable or 

increasing for over 10 years. 

4.	 A management plan based on maintaining sustained populations for turtles is in effect. 

5.	 International agreements are in place to protect shared stocks. 

26
 
Endangered Species Act Biennial Report to Congress 

PlanTitle: Sacramento River Winter-Run Chinook 

Salmon 

Planning Stage: Draft 

Notice of Availability Date: 8/7/97 

Species Covered 

Common Name Population Name NMFS Status 

Salmon, Chinook Sacramento River Winter-run Endangered 

Plan Status 

The Sacramento River winter-run chinook salmon was listed as threatened on an emergency 

basis on August 4, 1989, and was listed as threatened on November 30, 1990. In response to a 

petition received in June 1991, NMFS reclassified this species as endangered in January 1994. A 

recovery team has been appointed to prepare a recovery plan. A draft recovery plan was made 

available for public review and comment on August 7, 1997 (62 FR 42508). A final version of 

the plan should be available at the end of 1999. 

Recovery Actions 

Most of the recovery actions for the winter-run chinook salmon involve consultations under 

section 7 of the ESA with Federal agencies that either control the diversion of water in the river 

or permit activities by other water users (i.e. the Bureau of Reclamation and the U.S. Army Corps 

of Engineers). This species depends on an adequate flow of water at a specific temperature in the 

Sacramento River. 

NMFS is a member of the Bureau of Reclamation's Temperature Advisory Committee, and is 

working with the Bureau on temperature management strategies to attract winter-run as far up the 

Sacramento River as possible and increase the amount of spawning in the reach of the river that 

the Bureau can manage with available water. NMFS is also working with the State of California 

by reviewing impacts of state actions on winter-run chinook. 

In 1988, NMFS, the State of California, the Fish and Wildlife Service, and the Bureau of 

Reclamation signed a cooperative agreement to restore Sacramento River winter-run chinook. 

The Ten-Point Winter-Run Restoration Plan includes actions such as raising the gates at the 

Bureau's Red Bluff Diversion Dam from December 1 through April 1 to allow free passage of 

adult winter-run chinook to suitable spawning habitat and maintaining water temperatures at 

levels below lethal limits in the reach of river above Red Bluff Dam that is used for spawning. A 

biological opinion issued in 1993 to the Bureau of Reclamation on the operation of its Central 

Valley Project, and the State Water Project controls activities in most of the species' important 

habitats. 

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Endangered Species Act Biennial Report to Congress 

In June 1991, NMFS issued a biological opinion to the Army Corps of Engineers stating that 

issuance of a permit to the Glenn-Colusa Irrigation District (GCID) would likely jeopardize the 

continued existence of the Sacramento River winter-run chinook because GCID did not plan to 

install new fish screens that would exclude fish when water is diverted from the Sacramento 

River. NMFS requested that GCID take immediate action to prevent a take of juvenile winterrun chinook before they would pass GCID's pumping station. NMFS requested the Department 

of Justice move to enjoin the operation of the pumping plant when the fish are likely to be taken. 

A Federal District Court Judge issued a temporary restraining order against GCID which was 

effective on August 19, 1991, and cuts diversion of water by about 50 percent. GCID currently 

operates under a court-approved plan that protects winter-run chinook salmon. They are building 

a new fish screen to reduce entrainment of juvenile salmonids. 

NMFS has consulted under section 7 with the Pacific Fishery Management Council. Because a 

direct take of Sacramento River winter-run chinook salmon by sport or commercial fishermen is 

not allowed, the biological opinion includes measures in the incidental take statement to decrease 

the potential incidental take of the species. These measures include not approving an early 

opening of the commercial fishery south of Point Arena, California, and delaying the recreational 

fishery for 2 weeks and closing it 2 weeks early south of Point Arena. Fishing regulations in 

1996 include increased size limits in California recreational and commercial ocean salmon 

fisheries to further reduce impacts on winter-run chinook salmon. 

The Bureau of Reclamation recently re-initiated section 7 consultation with NMFS for impacts of 

the Central Valley Project to winter-run chinook salmon and other listed/proposed species, 

including Central Valley steelhead (listed threatened), Central Valley fall/late-fall chinook 

(proposed threatened), and Central Valley spring-run chinook (proposed endangered). This 

consultation, along with restoration actions implemented pursuant to the Central Valley Project 

Improvement Act and Cal-Fed initiatives, should result in further improvements to winter-run 

chinook salmon habitat conditions in the Sacramento River and Delta. 

28
 
Endangered Species Act Biennial Report to Congress 

PlanTitle: Snake River Salmon
 

Planning Stage: Draft 

Notice of Availability Date: 1995 

Species Covered 

Common Name Population Name NMFS Status 

Salmon, Chinook Snake River Spring/Summer 

Run 

Threatened 

Snake River Fall Run Threatened 

Salmon, Sockeye Snake River Endangered 

Plan Status 

A Snake River Salmon Recovery Team was formed in 1991; it submitted recommendations for a 

NMFS recovery plan in June of 1994. The NMFS reviewed and re-worked these 

recommendations and in March of 1995 a draft recovery plan was released for public comment. 

Many of the recovery actions being taken in the Columbia River basin are based upon the 

recommendations made in that draft Plan. A working draft of what was intended to be the Final 

Recovery Plan was released in August of 1997, but by that time, broad-based recovery efforts 

underway in other venues had made redundant the NMFS-driven recovery planning process in 

the Snake and Columbia River basins. This report details some of the ongoing measures 

instituted by the 1995 Draft Plan and summarizes the recovery efforts being generated in other 

forums. 

Recovery Actions Initiated by the 1995 Proposed Plan 

Institutional Structure, Accountability, and Monitoring 

The 1995 Proposed Plan determined that the decision-making process for ESA concerns in the 

Columbia and Snake River basins needed to be improved. The Plan’s framers felt that because 

there are so many (sometimes conflicting) jurisdictions and authorities in the Region, it was vital 

to make profound institutional changes in order to prevent further listings and achieve recovery 

as rapidly and economically as possible. As a result, the very first recommendation made in the 

Proposed Recovery Plan was to “Create and implement a coordinated institutional structure to 

ensure a unified approach to recovery of ESA-listed stocks.” The second main section of this 

report—Multi-species Recovery Efforts—details how this recommendation is being carried out. 

Delisting Criteria 

One of the ESA-mandated requirements of any recovery plan is the establishment of objective 

and measurable criteria by which it can be deemed that the listed species in question no longer 

requires ESA protection. NMFS established these criteria for Snake River salmon in 1995; they 

29
 
Endangered Species Act Biennial Report to Congress 

fall into two major categories: (1) Remedying the environmental (and other) factors that have 

reduced the stocks to levels which are in danger of extinction; and (2) rebuilding populations to 

levels where there is evidence of improved productivity, even when considering the potential 

impacts of severe stochastic environmental events (e.g., protracted drought, oceanic El Niño 

effects, etc.). Both of these categories must be achieved in order to consider delisting. To 

determine (2) above, NMFS proposed to use cohort replacement rates and numeric delisting 

criteria. 

The natural cohort replacement rate describes the rate at which each subsequent cohort, or 

generation, replaces the previous one. When this rate is exactly 1.0, a population is neither 

increasing nor decreasing. If the ratio remains less than 1.0 for extended periods, a population is 

in decline, and could continue into extinction--a risk which originally led to listing Snake River 

salmon. For population rebuilding, the natural cohort replacement rate must be greater than 1. 

For delisting to be considered, the eight-year geometric mean cohort replacement rate of a listed 

species must exceed 1.0. For Snake River spring/summer chinook salmon, this goal must also be 

met for 80% of the index areas available for estimating cohort replacement rates. 

For sockeye salmon, the numerical escapement goal is an eight-year (approximately twogeneration) geometric mean of at least 1,000 natural spawners returning annually to Redfish Lake 

and 500 naturally-produced spawners in each of two other Snake River Basin lakes. The 

numerical escapement goal for Snake River fall chinook salmon is an eight-year geometric mean 

of at least 2,500 naturally-produced spawners in the mainstem Snake River annually. Snake 

River spring/summer chinook salmon have two numeric delisting criteria; both must be met for 

delisting to be considered. The first numerical escapement goal for Snake River spring/summer 

chinook salmon is an eight-year geometric mean corresponding to at least 60% of the pre-1971 

brood year average redd counts for 80% of the available index areas. The second numerical 

escapement goal for spring/summer chinook salmon is an eight-year geometric mean equal to 

60% of the 1962-1967 brood year average count of naturally-produced spawners past Ice Harbor 

Dam (goal is equal to 31,440 natural spawners). 

Tributary Ecosystem 

Land and water management actions, including water withdrawals, unscreened water diversions, 

stream channelization, road construction, timber harvest, livestock grazing, mining, and outdoor 

recreation have degraded important salmon spawning and rearing habitats. To protect tributary 

ecosystem health, NMFS proposes a three part approach: (1) Protect remaining high quality 

habitat by ceasing activities that would degrade ecosystem functions and values that listed fish 

need, (2) restore degraded habitats, and (3) provide connectivity between high quality habitats. 

Federal lands and Federal actions should bear, as much as possible, the burdens of recovering 

listed salmon species and their habitat. NMFS' March, 1995 biological opinion on eight Land 

and Resource Management Plans in the Snake River Basin established guidelines to maintain or 

improve aquatic habitats. These guidelines are in effect until geographically specific 

environmental impact statements for ecosystem management are completed. The U.S. Forest 

Service adopted standards collectively called "PACFISH" in February, 1995; these standards 

sunset in August, 1996, and were extended by the Forest Service until the East Side EIS's are 

completed. However, non-Federal lands constitute approximately 35 percent of the Snake River 

30
 
Endangered Species Act Biennial Report to Congress 

salmon critical habitat. Therefore, an ecosystem approach that emphasizes integrated Federal 

and non-Federal land management is needed. To achieve this, all stakeholders in a subbasin or 

watershed are encouraged to participate in management partnerships. The Recovery Plan also 

proposes actions that will reduce the loss of listed species at water withdrawal sites, rebuild 

salmon populations by providing adequate instream flows and improving fish passage at barriers, 

reduce losses of listed salmon associated with poor water quality, and reduce impacts on salmon 

resulting from recreational activities. 

Mainstem and Estuarine Ecosystem 

In the mainstem and estuarine ecosystem, salmon face problems associated with their 

downstream and upstream migrations. The journey through the lower Snake and Columbia 

Rivers has become more hazardous since eight hydroelectric dams were built and their reservoirs 

created. Each dam delays juvenile fish in their transition to the ocean environment and exacts 

additional losses. Seventy percent of the 482 miles between the mouth of the Columbia River 

and Lewiston/Clarkston on the Snake River has been converted from free-flowing river into 

reservoirs. This change has slowed the rate of downstream travel for smolts and increased the 

amount of habitat favorable to predator species. Hatchery fish and exotic species compete with 

and prey on the listed salmon in the mainstem ecosystem. 

The plan prescribed immediate actions to improve mainstem survival and called for a new and 

rapid set of evaluations to determine the efficacy of these actions, and evaluations to determine 

the feasibility and likely biological benefits of major structural modifications of dams. 

Management actions already taken to improve river conditions include drawdown of reservoirs 

behind the dams to minimum operating pool, increased river flows, and increased spill at dams. 

Structural changes implemented to improve fish survival past the dams include installation of 

extended length screens, construction of bypass systems (seven of the eight dams these fish must 

pass now have bypasses), and design and installation of a prototype surface diversion structure. 

The main evaluation set up by the Proposed Plan was a process to determine whether surface 

diversion—in combination with improved river conditions (i.e., increased flow and spill)—and 

barge transportation would sufficiently improve survival to achieve recovery, or whether major 

structural modification of dams (i.e., drawdowns below minimum operating pool) would be 

necessary. The decision on which route to recommend to Congress and to the system managers 

has been termed “The ‘99 Decision,” as it is intended to be completed in June of 2000. The 

primary program for modeling and evaluating the possible options are the Plan for Analyzing and 

Testing Hypotheses, or PATH and NMFS’ Cumulative Risk Initiative (CRI). PATH and NMFS 

scientists have been laboring intensively for the past three years to deliver the best possible 

science to the decision makers. Their final recommendations for operating the Columbia River 

hydropower system will be out in late summer of 2000. 

To minimize predation and competition problems in the migration corridor, the Proposed 

Recovery Plan contains actions to control predation by squawfish, birds, marine mammals, and 

non-native fishes such as smallmouth bass, walleye, and channel catfish. Measures are also 

proposed to reduce American shad populations in the Columbia River because they both prey on 

31
 
Endangered Species Act Biennial Report to Congress 

and compete with juvenile salmon. 

Environmental conditions in the Columbia River estuary and nearshore ocean environments are 

factors that influence juvenile salmonid survival. The Proposed Recovery Plan calls for 

improvement in the estuarine ecosystem through better management of dredging and water 

quality issues. 

Harvest Management 

Snake River salmon are not directly targeted for harvest, but they are incidentally caught by 

commercial, recreational, and tribal fisheries in the ocean and in the Columbia and Snake Rivers. 

Incidental harvest in the ocean of Snake River sockeye salmon and Snake River spring/summer 

chinook salmon is minimal. However, fall chinook salmon are caught incidentally in commercial 

and sport fisheries from Southeast Alaska to California, in non-treaty inriver sport and 

commercial fisheries, and in treaty fisheries above Bonneville Dam. In each of these fisheries, 

listed Snake River fall chinook are mixed with a number of other natural and hatchery-origin 

stocks. At present, these fisheries are managed through a complex system of interrelated forums. 

The draft Recovery Plan recommends amending the existing inriver harvest management rules so 

that they incorporate explicit management criteria to protect Snake River salmon. To minimize 

the number of fall chinook caught in ocean fisheries, NMFS proposes to implement a 

management strategy that is consistent with the Pacific Salmon Commission's management 

objectives for adult chinook. These goals are established for a number of stocks and are based on 

a chinook rebuilding program that was fully implemented in 1984. This approach takes a broad 

view of stock protection and focuses on the coastwide status of chinook stocks including those 

from Puget Sound, the Washington and Oregon coasts, and the Columbia River. 

Artificial Propagation 

Artificial propagation of salmon in the Columbia River Basin has successfully contributed to 

ocean and inriver commercial, sport, and tribal fisheries. In some cases, hatchery production has 

slowed the decline of natural salmon populations or helped preserve them. However, effects 

from intensive hatchery production (such as supporting harvest rates in excess of what the natural 

populations can withstand, using natural fish for hatchery broodstock, and causing introgression 

into natural gene pools) have also contributed to the continued decline of some natural salmon 

populations. Ecological interactions between hatchery fish and natural fish such as competition, 

predation, displacement, and disease transfer need to be minimized. 

Under the draft recovery plan, captive broodstocks are being maintained to conserve remaining 

sockeye and spring/summer chinook salmon gene pools. Other supplementation efforts designed 

to support listed salmon recovery are also underway in the Snake River Basin. 

The draft Recovery Plan also suggests protecting listed species from excessive genetic 

introgression, minimizing impacts on listed salmon resulting from interactions between 

Columbia River Basin hatchery salmon and natural salmon, improving the quality of fish 

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Endangered Species Act Biennial Report to Congress 

released from hatcheries, reducing predation and competition interactions between listed salmon 

and steelhead and hatchery trout, restoring listed chinook by reintroducing them to historic 

habitat, and conducting research for the purpose of optimizing production and conserving natural 

populations. 

Multi-species Recovery Efforts 

As stated earlier, one of the draft Recovery Plan’s primary recommendations was to bring 

recovery planning under a centralized institutional structure in order to avoid conflict and wasted 

effort. While this work was underway, other species in the basin were listed under the ESA and 

still others were determined to be in failing health. This state of affairs pointed up the necessity 

to centralize regional recovery efforts, not just for salmon, but for all the imperiled species in the 

basin. This regional effort is being coordinated through the Multi-Species Framework project 

and the Columbia Basin Forum. Participants include state governments, Tribal governments and 

Federal agencies, with a management committee representing all three entities. Participants hope 

that this effort will help to identify areas of consensus, and ultimately lead to broader regional 

agreement on the future management direction for the Columbia Basin. 

The Columbia Basin Forum 

Formerly known as the Three Sovereigns, the Columbia Basin Forum is made up of 

representatives from the four Northwest states, the 13 Columbia Basin Tribes, and the Federal 

agencies involved in the Columbia River. Its purpose is to provide a high-level policy forum to 

coordinate the use of its members’ respective authorities in addressing fish and wildlife 

management and related habitat issues in the Columbia Basin. The Forum can provide a place for 

regional governments and interested parties in the region to discuss alternative management 

approaches being developed in the Framework Project and test regional agreement on the various 

alternatives. The Forum also will provide an opportunity for public participation. 

Through the Forum, each management entity will engage in regional discussion of the available 

alternatives in each of the four “Hs” (habitat, harvest, hatcheries, and hydropower). The Federal 

agencies, for example, will specifically discuss a draft “All-H” paper and a draft Biological 

Assessment. The states and Tribes will do the same, bringing any particular management or 

recovery plans forward for discussion. Other regional interests will also be invited to participate. 

The Multi-species Framework 

The Framework project is an effort to develop the fundamental options and outcomes necessary 

to make informed management decisions. The project solicited alternative management proposals 

from stakeholders in the region and consolidated those 27 alternatives into seven. The 

Framework created two workgroups to analyze the alternatives for their biological, social, and 

economic effects. Regional input and comments are being solicited on the alternatives and 

analysis through outreach activities throughout the summer. Federal, state, and Tribal 

representatives will participate in those outreach activities together. Members of the Forum (see 

below) will also discuss these alternatives. A draft report will be available for public review in 

the fall. 

33
 
Endangered Species Act Biennial Report to Congress 

At the same time, the Corps of Engineers has since 1995 been conducting a feasibility study on 

alternative actions for the lower Snake River dams. The Environmental Impact Statement being 

prepared by the Corps examines a number of alternatives that are somewhat different from those 

being considered in the Framework. (This is because the Corps’ process was set up to examine 

actions only on the Snake River.) To aid in this effort, the National Marine Fisheries Service 

used the output from the PATH and CRI process (mentioned above) to analyze the ecological 

effects likely to result from the various alternatives. The Corps intends to release a draft of the 

EIS for public comment this fall. 

Many in the region are optimistic that the Framework project and Forum process will be able to 

identify areas of consensus within the region to guide Columbia Basin fish and wildlife 

restoration. Implementation of any regional plans requires more detail than either the Framework 

or the Forum can provide. Accordingly, Federal, state and Tribal implementation plans can be 

expected in the future. For example, Federal agencies with specific responsibilities under the 

Endangered Species Act, Indian treaties, and other authorities need to produce a management 

plan for the Federal hydropower system well before the end of 1999. For this reason, the Federal 

agencies are developing a detailed proposal for operation and configuration of the FCRPS, which 

they will put forward in the fall. 

A plan for managing the Federal hydropower system only makes sense in the context of all the 

human activities that affect fish and wildlife. Therefore, as stated above, the Federal agencies are 

developing a All-H Paper that explains how the proposed hydropower management plan can fit 

into an overall recovery strategy. The Federal agencies intend to work within the Framework to 

develop alternatives that can be incorporated into the All-H paper. In addition, harvest and 

hatchery regimes for many Columbia River fisheries are currently being discussed in negotiations 

over a new Columbia River Fish Management Plan within the U.S. v. Oregon process. The 

Federal agencies have stated their intention that any agreement that comes out of that process 

would form the harvest and hatchery pieces of the All-H Paper. 

Recovery Goals 

By working to improve survival in every segment of the salmon’s life history, the ongoing 

recovery efforts necessarily address the effects of a broad range of activities on many of the 

region’s ecological components. When these efforts are added to the basinwide forums, a 

mechanism for bringing about the recovery of the ecosystem as a whole emerges. This is vastly 

preferable to concentrating on limited numbers of actions in geographically disparate areas. The 

salmon are, or were, pervasive in the region. In recovering them, the basin managers will have 

gone a long way toward restoring the resources upon which they depend. Moreover, they will 

have taken a major step toward bringing back many of the region’s other species that now exhibit 

badly depleted numbers. 

34
 
Endangered Species Act Biennial Report to Congress 

PlanTitle: Gulf Sturgeon
 

Planning Stage: Final 

Plan Approval Date: 9/22/95 

Species Covered 

Common Name Population Name NMFS Status 

Sturgeon, Gulf Range-wide Threatened 

Plan Status 

During this report period, increased interest in Gulf sturgeon by government and non-government 

agencies and institutions have accomplished much toward its recovery. Genetic analyses of Gulf 

sturgeon indicate the population is divided into five genetically distinct stocks, each occupying a 

unique watershed or geographical unit. Also, Gulf sturgeon spawning and resting habitat have 

been documented and characterized in three river systems. Population surveys and freshwater 

and marine movement and migratory behavior have been studied in six watersheds. In addition, 

Gulf sturgeon outreach activities have contributed much toward public education. 

Recovery Actions 

NMFS, U.S. Fish & Wildlife Service and the Gulf Coast Fishery management Council published 

a recovery plan for the Gulf sturgeon. The major actions recommended in the plan are: 

1.	 Conduct and refine field investigations to locate important habitats. 

2.	 Characterize riverine, estuarine, and neritic essential habitat. Develop and implement 

population sampling and monitoring techniques. 

3.	 Eliminate potential for introductions of non-native stock or other sturgeon. 

4.	 Conduct life history studies on the requirements of little-known life stages. 

5.	 Identify potential harmful chemical and water quantity and quality changes associated 

with surface water restrictions. 

6.	 Identify and eliminate point and non-point sources of chemical contaminants. 

7.	 Seek resolution of conflict between authorized projects and restoration of fish 

populations. 

8.	 Reduce or eliminate incidental mortality. 

9.	 Restore natural riverine habitats. Utilize existing authorities to protect habitat, and where 

inadequate, enact new laws and regulations. 

10.	 Identify dam and lock sites which offer the greatest flexibility for successful restoration of 

essential habitats. 

11.	 Modify specific navigation projects which alter riverine habitats or modify thermal or 

substrate characteristics of those habitats. 

12.	 Implement projects or actions which will achieve recovery plan objectives. Increase 

35
 
Endangered Species Act Biennial Report to Congress 

effectiveness and enforcement of state and federal take prohibitions. 

13.	 Seek funding for recovery actions. Identify and eliminate known and potential impacts to 

water quantity and quality associated with existing and proposed uses and water 

diversions. Assess the relationship between groundwater pumping and reduction of 

groundwater flows and quantify loss of riverine habitat related to reduced groundwater inflows. 

Recovery Goals 

The primary short-term recovery objective is to prevent further reduction of existing wild 

populations of Gulf sturgeon within the subspecies` range. The long-term recovery objective is 

to establish population levels that would allow delisting of the Gulf sturgeon in discrete 

management units. Delisting could be considered within 30 years, if recovery criteria are met. 

Following delisting, a long-term fishery management objective is to establish a self-sustaining 

population that could withstand directed fishing pressure within discrete management units. 

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Endangered Species Act Biennial Report to Congress 

PlanTitle: Shortnose Sturgeon
 

Planning Stage: Draft 

Plan Approval Date: December, 1998 

Species Covered 

Common Name Population Name NMFS Status 

Sturgeon, Shortnose Range-wide Endangered 

Plan Status 

In December 1998, NMFS will finalize and distribute the final recovery plan for shortnose 

sturgeon. 

Recovery Actions 

Actions Needed: 

1. Establish Listing Criteria for Shortnose Sturgeon Population Segments 

2. Protect Shortnose Sturgeon and their Habitats 

3. Rehabilitate Shortnose Sturgeon Populations and Habitats 

4. Implement Recovery Tasks 

Cost of Recovery Tasks: The costs of recovery are undeterminable at this time. Refer to the 

Implementation Schedule for cost estimates for individual tasks. Cost estimates were not 

available for some tasks because the actual actions needed are not known (for example: costs of 

restoring access to spawning areas located above dams will vary depending on the type of fish 

passage implemented). In addition, some tasks are a high priority for a large number of 

population segments. If these tasks are conducted on several rivers concurrently, costs may be 

significantly reduced. Therefore, accurate cost estimates were impossible to predict. 

Date of Recovery: There is evidence that some population segments are already starting to 

recover. Delisting of all population segments could be initiated by 2024, if all recovery criteria 

are met. 

Recovery Goals 

Recovery Goal: To delist shortnose sturgeon populations throughout their range.
 

Recovery Objective and Criteria: To recover populations to levels of abundance at which they no
 

longer require protection under the ESA. For each population segment, the minimum 

population size will be large enough to maintain genetic diversity and avoid extinction.
 

37
 
Endangered Species Act Biennial Report to Congress 

Status Discussions for Species Listed under
 

the Endangered Species Act of 1973.
 

Spawning Sockeye salmon 

38
 
Endangered Species Act Biennial Report to Congress 

Listed Species Status 

Green Turtle: Chelonia mydas 

Listing Date: July 28, 1978 

The green turtle was listed under the U.S. Endangered 

Species Act (ESA) on July 28, 1978. The species is 

listed as threatened throughout its range except for 

the Florida and Pacific Mexico breeding populations 

which are listed as endangered. Historically, the greatest cause of decline for green turtles has 

been commercial harvest for eggs and meat. This threat is still a major cause of decline outside 

the U.S. 

Species Biology: 

Adult green turtles are the largest of the hard-shelled turtles. Average carapace length and mass 

of nesting females range from 92 cm and 110 kg to 109 cm and 182 kg. The carapace is smooth 

and colored grey, green, brown and black. The plastron is yellowish white. An adult male can 

be easily differentiated from an adult female in that the male has a thick prehensile tail that 

extends far beyond the posterior margin of its carapace. Green turtle hatchlings weigh 

approximately 25 g and measure approximately 50 mm in length. The hatchling carapace is 

colored blue-black and the plastron is creamy-white. Green turtles are distinguished from other 

sea turtle species by the presence of a single pair of large prefrontal scales between the eyes, and 

a strongly serrated lower jaw. The common name “green turtle” specifically refers to the color of 

the animal’s fat. 

Distribution and Abundance: 

In the southeastern United States, green turtles are found in waters around the U.S. Virgin 

Islands, Puerto Rico, and the continental U.S. from Texas to Massachusetts. Important feeding 

grounds in Florida include the Indian River Lagoon, the Southeast Florida coastline, the Florida 

Keys, Florida Bay, Homosassa, Crystal River and Cedar Key. The primary nesting sites in the 

U.S. Atlantic are along the east coast of Florida, with additional sites in the U.S. Virgin Islands 

and Puerto Rico. 

Green turtles are found throughout the North Pacific, occasionally ranging as far north as Eliza 

Harbor, Admiralty Island, Alaska, and Ucluelet, British Columbia. In the eastern North Pacific, 

green turtles have been sighted from Baja California to southern Alaska. In the central Pacific, 

green turtles can be found at most tropical islands. In U.S. Hawaiian waters, green turtles are 

found around most of the islands in the Hawaiian Archipelago. The primary nesting site is at 

French Frigate Shoals in the northwestern Hawaiian island chain. 

Total population size for the green turtle is not known, and trends are particularly difficult to 

assess because of wide year-to-year fluctuations in numbers of nesting females, difficulties of 

39
 
 

Endangered Species Act Biennial Report to Congress 

conducting research on early life stages, and long generation time. Present estimates of females 

nesting each year in the U.S. average 675 in Florida and 500 in Hawaii. Nesting in Florida is 

likely reduced from historical levels and has been greatly reduced in the Dry Tortugas; however, 

recent data (1989-1998) indicate that nesting may now be stable or increasing. In Hawaii, 

nesting numbers are lower than historical levels, but have increased substantially in the past 20 

years. Populations in Surinam, Ascension Island, and Tortuguero, Costa Rica, appear to be 

stable, but other populations including Seychelles; Europa, Reunion; Indonesia; Peninsular, 

Malaysia; and Ogaswara Island, Japan continue to decline. 

There are several principal threats to green turtles in the U.S. and these include loss of habitat, 

fibropapilloma disease, boat and ship strikes, and incidental capture in gill nets. Worldwide, 

commercial harvest and egg poaching are the primary causes of population decline. Turtles are 

harvested for food, leather and jewelry, and small turtles are sometimes stuffed for curios. 

Major Impacts/Threats in the Nesting Environment: 

•	 In the United States, harvesting of nesting green turtles and egg poaching is infrequent. 

However, in other parts of the world, harvesting of nesting turtles and egg poaching is a 

serious threat. Animal predation of eggs and hatchlings is also a concern in some areas. 

•	 Artificial lighting can cause disorientation or misorientation of both adults and hatchlings. 

Green turtle hatchlings are attracted to artificial light, which disrupts their natural seafinding behavior and can result in increased predation and mortality. In addition, adult 

females are discouraged from nesting in highly developed areas with intense artificial 

lighting. 

•	 Beach armoring (seawalls, revetments, riprap, sandbags and sand fences) to protect 

property from erosion can cause the loss of dry nesting beach and/or interfere with access 

to suitable nesting sites. However, natural processes of beach erosion are not generally a 

significant threat. 

•	 Beach nourishment results in heavy machinery, pipelines, increased human activity and 

artificial lighting on a project beach, and can cause the burial of nests and disturbance of 

nesting turtles if not regulated properly to occur outside the nesting season. Beach 

nourishment can result in alteration of beach or sand characteristics which can affect 

nesting and nest success. 

•	 Repeated mechanical raking of nesting beaches by heavy machinery can result in 

compacting sand and cause tire ruts which may hinder or trap hatchlings. Rakes can 

penetrate the surface and disturb or uncover a nest. Disposing of the raked debris on the 

high beach can cover nests and may alter nest temperature affecting temperature 

dependent sex determination mechanisms. 

•	 Human disturbance of nesting females is a serious concern. Also, heavy utilization of 

nesting beaches by humans may result in lowered hatchling success due to sand 

compaction. 

•	 The placement of physical obstacles (e.g. beach chairs, recreational beach equipment) on 

a beach can hamper or deter nesting attempts as well as interfere with the incubation of 

eggs and the emergence of hatchlings. 

•	 The use of vehicles on beaches is a serious problem in certain areas. It may result in 

40
 
Endangered Species Act Biennial Report to Congress 

decreased hatchling success due to sand compaction, or directly kill hatchlings and adults. 

Tire ruts may also interfere with the ability of hatchlings to get to the ocean. The use of 

vehicles at night on nesting beaches can deter nesting females and misorient hatchlings. 

•	 The invasion of nesting sites by non-native beach vegetation can lead to increased erosion 

and degradation of nesting habitat. Trees shading a beach can also change nest 

temperatures, altering the natural sex ratio of the hatchlings. 

Major Impacts/Threats in the Marine Environment: 

•	 It is estimated that before the implementation of turtle excluder device (TED) 

requirements, the U.S. commercial shrimp fleet captured approximately 925 green turtles 

each year; approximately 225 of those captures were fatal. With TED regulations in place 

the incidental capture and mortality of green turtles has been greatly reduced. Nonshrimp bottom and mid-water trawl fisheries also capture and can kill green turtles and 

efforts are underway by NMFS to address these threats. Turtles are taken by purse seine 

fisheries in the Atlantic and Gulf of Mexico, but the magnitude of the take is not currently 

known. Several thousand commercial vessels and an extensive recreational fishery are 

involved in hook and line fishing for various coastal species. The capture of turtles in 

this fishery is believed to be common, but the number is not known. 

•	 Throughout the late 1980's and early 1990's, significant numbers of green turtles were 

killed by gill and trammel net fisheries off the eastern coast of central Florida. However, 

in 1995, gill and trammel net fisheries were banned from operating in Florida state 

waters. Gill nets fished in other areas of the species range remain a serious threat. Pound 

net fisheries are primarily a problem in Virginia waters, where turtles become entangled 

in the gear and can drown. In North Carolina, live turtles are often released from pound 

nets. Green turtles are incidentally taken by the U.S. pelagic longline fisheries in the 

Western North Atlantic, Eastern Pacific, and Hawaii when they are hooked and/or 

become entangled with the mainline or buoy line. Traps, commonly used to capture 

crabs, lobster and reef fish result in incidental takes of green turtles when they become 

entangled in the trap lines and drown. The impact of trap line gear on green turtle 

populations has not been quantified. 

•	 Green turtles can consume a wide variety of marine debris such as plastic and styrofoam 

pieces, tar balls, balloons, plastic bags, and plastic pellets. Effects of consumption 

include interference in metabolism or gut function, even at low levels of ingestion, as 

well as absorption of toxic byproducts. Discarded monofilament fishing line and 

abandoned netting can entangle turtles, causing injury and/or death. 

•	 A disease, known as fibropapillomatosis (FP), originally identified in green turtles, but 

now affecting loggerhead, Kemp’s ridley, and olive ridley turtles as well, has emerged as 

a serious threat to sea turtle recovery. In the U.S., the disease is most notably present in 

green turtles of Hawaii, Florida, and the Caribbean, but is found at other sites around the 

world as well. FP is expressed as tumors which occur primarily on the skin and eyes, and 

the disease can be fatal. In Hawaii, green turtles afflicted with FP have a high incidence 

of tumors in the oral cavity, whereas oral tumors have not been reported from Florida or 

other areas. The cause of the disease remains unknown, however, a viral etiology is 

suspected. The expression of the disease has been systematically monitored in several 

locales in Hawaii. At a study site on southern Molokai, for example, where tumors were 

41
 
Endangered Species Act Biennial Report to Congress 

virtually unknown before 1988, the prevalence of tumored turtles ranged from 42-56% 

during the 1995-1997 surveys. In Florida, up to 50% of the juvenile green turtles 

captured in the Indian River Lagoon are infected, and there are similar reports from other 

sites in Florida, including Florida Bay, as well as from Puerto Rico, and the U.S. Virgin 

Islands. In Florida, the disease has been documented affecting up to 13% of loggerheads 

inhabiting Florida Bay. Fibropapillomatosis is considered the primary impediment to the 

full recovery of the Hawaii green turtle population and the disease may hinder the 

recovery of green turtle populations elsewhere as well. Research to determine the cause 

of this disease is a high priority and is underway at federal, state, and private institutions. 

•	 Illegal harvesting of green turtles is uncommon in the mainland U.S. Illegal take of green 

turtles in the Caribbean, particularly near Puerto Rico, is a more significant problem; 

however, no estimates of take exist. Legislation and treaties to protect and conserve 

green turtles are more extensive than they have been in the past, although laws are often 

poorly enforced, especially among developing nations and smaller islands where 

resources and geography limit implementation. 

•	 Green turtles are at risk when encountering marine pollution such as oil spills. 

Respiration, skin, blood chemistry and salt gland functions are affected. Pesticides, heavy 

metals, and PCB's have been detected in turtles and eggs, but the effects ares unknown. 

•	 Dredging can result in habitat destruction by degrading nesting sites and/or foraging 

grounds. Hopper dredges can also kill turtles caught in dragheads. NMFS has 

implemented restrictions on hopper dredging activities in the Gulf and Atlantic to reduce 

the likelihood of dredges encountering turtles. 

•	 In areas where recreational boating and ship traffic is intense, propeller and collision 

injuries are common and likely play a significant role in hampering recovery. This is a 

particularly difficult issue to address, given the number of registered vessels and their 

wide-ranging activities. 

•	 Marina and dock construction result in the degradation and/or destruction of green turtle 

foraging habitat. This development also leads to increased boat traffic, increasing the risk 

of propeller and vessel collision injuries. 

•	 Coastal power plants which draw their cooling water from nearshore and estuarine waters 

can entrain sea turtles and cause mortality. Measures have been put in place to reduce the 

risk to sea turtles and studies are ongoing to develop additional measures. 

•	 Underwater explosions (e.g. gas and oil structure removal and testing using explosives) 

can kill or injure turtles, and may destroy or damage habitat. NMFS closely monitors oil 

rig removals and has instituted measures to minimize this threat. 

Conservation Activities: 

•	 In 1998, NOAA Fisheries and the U.S. Fish and Wildlife Service (USFWS) published 

recovery plans for five species of Pacific sea turtles, including one distinct nesting 

population of the green turtle. Plans are underway to revise some of the U.S. Atlantic 

recovery plans which were completed in the early 1990s. These plans describe and 

prioritize actions which are necessary to conserve and recover the species. 

•	 NMFS oversees a national sea turtle stranding program. This program consists of state 

and Federal biologists and private citizens who respond when a sea turtle strands injured 

42
 
Endangered Species Act Biennial Report to Congress 

or dead on coastal beaches. The program has increased our knowledge of turtle biology 

and the human-related impacts to the turtle populations. 

•	 To address the impact of incidental capture in the shrimp trawl fishery, TEDs were 

developed and, in 1992, were required in all shrimp trawlers (with a few exceptions) from 

North Carolina through Texas. Additionally, TED requirements were amended, effective 

March 1997, to enhance protection of sea turtles by establishing Shrimp Fishery Sea 

Turtle Conservation Areas (SFSTCAs) in the western Gulf and in the Atlantic along the 

coast of Georgia and South Carolina. 

•	 A multi-disciplinary research program is underway to study the cause and effects of the 

disease fibropapillomatosis (FP). Research has been initiated on the possible etiologies 

of the disease, including viruses, parasites, and environmental pollutants. In addition to 

field and laboratory research, statistical analyses and modeling studies are underway to 

link fibropapilloma incidence and severity to key aspects of green turtle population 

dynamics and assess impacts of the disease on population recovery. 

•	 Progress has been made in the study of migratory movements of post-nesting sea turtles, 

to elucidate routes of travel and identify resident foraging grounds. NOAA Fisheries 

scientists have conducted highly successful satellite telemetry studies with post-nesting 

Hawaiian and Florida green turtles. 

•	 On September 2, 1998, NMFS designated the coastal waters surrounding Culebra Island, 

Puerto Rico, critical habitat for green turtles. Critical habitat designations highlight the 

areas that are essential to the recovery of the species and alerts Federal agencies that these 

areas will be given special consideration during consultations under section 7 of the ESA. 

•	 Significant progress is being made in the monitoring of Hawaiian green turtles by the 

NMFS Honolulu Laboratory and the USFWS. A 5-year series of saturation surveys at 

East Island, French Frigate Shoals, completed in 1992, led to the development of rigorous 

quantitative methods that are now applied routinely to estimate the nesting population at 

East Island from annual partial-season surveys. Progress is also being made in monitoring 

juvenile and subadult Hawaiian green turtles in their nearshore habitat. 

•	 In the Hawaii and Atlantic pelagic longline fishery for tuna and swordfish, the incidental 

take of turtles is being monitored through a logbook and observer program. Workshops 

have been held to formulate research techniques to assess the population level effects of 

hooking and entanglement and to identify ways to reduce or mitigate incidental capture. 

In related research, satellite transmitters have been deployed on turtles hooked 

incidentally in the longline fishery to track post-release movements to better understand 

the long-term effects of hooking. Linkages between turtle movements and oceanographic 

processes are also being studied. 

•	 In the last decade considerable efforts have been expended to elucidate sea turtle 

management units through the use of genetic tools. There is a high degree of genetic 

structuring within ocean basins for all species except the leatherback. These genetically 

distinct management units arose as a result of genetic isolation facilitated by the species' 

natal homing. While the animals do appear to segregate when nesting, they commingle 

on the foraging grounds, sometimes thousands of miles away from their natal beach 

(where they hatched). The analyses of genetic material from turtles incidentally taken in 

various fisheries can tell us which populations are being impacted. The Hawaii-based 

longline fishery interacts with loggerheads from Japan, green turtles from Hawaii and 

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Endangered Species Act Biennial Report to Congress 

Mexico, and leatherbacks from both the eastern Pacific (Mexico or Costa Rica) and the 

southwestern Pacific (Irian Jaya, Malaysia, or Solomon Islands). Collection and analysis 

of genetic specimens from Mexican nesting beaches is just one facet of a broad 

collaboration between NMFS and Mexican scientists with the objective of monitoring 

and assessing turtle nesting along Mexico's Pacific coast. Green turtles inhabiting 

foraging habitats along the east coast of the U.S. come from nesting sites in Florida, the 

Caribbean, and the South Atlantic Ocean (east and west). 

•	 The Inter-American Convention for the Protection and Conservation of Sea Turtles was 

concluded on September 5, 1996 in Salvador, Brazil. This is the first international 

agreement devoted solely to the protection of sea turtles. The Convention will come into 

force when 8 countries have ratified it. The Convention establishes national sea turtle 

conservation programs in the signatory countries. These programs will include 

prohibiting intentional take (except for subsistence take as allowed under the convention), 

domestic or international sale of turtle parts or products, conservation and restoration of 

habitat and nesting beaches, and the promotion of efforts to enhance sea turtle 

populations. All commercial shrimp trawl vessels operating in waters regulated by the 

Parties will use TEDs to reduce the incidental capture of sea turtles. Some exceptions to 

the TED requirement are allowed. All Parties will establish a monitoring and observation 

program to verify that these measures are being applied. The convention is open only to 

States in the Americas or States with territories in the Americas, but it does call upon 

Parties to negotiate complementary protocols with non-Party states. 

•	 U.S. Public Law 101-162, Section 609 requires the U.S. to embargo shrimp harvested 

with commercial fishing technology which may adversely affect sea turtles. The import 

ban does not apply to nations that have adopted comparable sea turtle protection 

programs (i.e., require the use of TEDs) to that of the U.S. or those nations whose fishing 

environment does not pose a threat of incidental take of sea turtles. The Department of 

State (DOS) is the principal implementing agency of this law, with NMFS serving as 

technical advisor. NMFS has provided training in the installation and use of TEDs to 

many countries in Latin America, and more recently in Asia. 

Population Status 

Population Name Status Population 

Trend 

Population 

Estimate 

Critical Habitat 

Range-wide Threatened Increasing unknown Designated 

Florida Breeding population Endangered Increasing 675 nesting 

females2 

Mexican Breeding 

population 

Endangered Decreasing 470 nesting 

females3 

2

Average number of females nesting annually based on 3.5 nests/female/year for 1993-1997. 

3

Michoacan nesting populations 1994-1995 (Alvarado et al., 1995). 

44 
Endangered Species Act Biennial Report to Congress 

Designated Critical Habitat for Atlantic Green Turtles 

45
 
Endangered Species Act Biennial Report to Congress 

Listed Species Status 

Hawksbill Turtle: Eretmochelys imbricata 

Listing Date: June 2, 1970 

The hawksbill turtle's status has not changed since it was 

listed as endangered in 1970. It is a solitary nester, and 

thus, population trends or estimates are difficult to 

determine. The decline of nesting populations is accepted 

by most researchers. In 1983, the only known apparently 

stable populations were in Yemen, northeastern Australia, 

the Red Sea, and Oman. Commercial exploitation is the 

major cause of the continued decline of the hawksbill 

turtle. There is a continuing demand for the hawksbill's shell as well as other products including 

leather, oil, perfume, and cosmetics. Prior to being certified under the Pelly Amendment, Japan 

had been importing about 20 metric tons of hawksbill shell per year, representing approximately 

19,000 turtles. A negotiated settlement was reached regarding this trade on June 19, 1992. The 

hawksbill shell commands high prices (currently $225/kilogram), a major factor preventing 

effective protection. 

Species Biology 

The hawksbill is a small to medium-sized sea turtle. In the U.S. Caribbean, nesting females 

average about 62-94cm in straight carapace length. Weight is typically to 80 kg in the wider 

Caribbean, with a record weight of 127 kg. Hatchlings average about 42 mm straight carapace 

length and range in weight from 13.5-19.5 g. The following characteristics distinguish the 

hawksbill from other sea turtles: two pairs of prefrontal scales; thick, posteriorly overlapping 

scutes on the carapace; four pairs of coastal scutes; two claws on each flipper; and a beak-like 

mouth. The carapace is heart-shaped in very young turtles, and becomes more elongate or 

subovate with maturity. Its lateral and posterior margins are sharply serrated in all but very old 

individuals. The epidermal scutes that overlay the bones of the shell are the tortiseshell of 

commerce. They are unusually thick, and overlap posteriorly on the carapace in all but hatchlings 

and very old individuals. Carpacial scutes are often richly patterned with irregularly radiating 

streaks of brown or black on an amber background. The scutes of the plastron of Atlantic 

hawksbills are usually clear yellow, with little or no dark pigmentation. The soft skin on the 

ventral side is cream or yellow, and may be pinkish-orange in mature individuals. The scales of 

the head and forelimbs are dark brown or black with sharply defined yellow borders. There are 

typically four pairs of inframarginal scales. The head is elongate and tapers sharply to a point. 

The lower jaw is V-shaped. 

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Endangered Species Act Biennial Report to Congress 

Hawksbills utilize different habitats at different stages of their life cycle. Posthatchling 

hawksbills occupy the pelagic environment, taking shelter in weedlines that accumulate at 

convergence points. Hawksbills reenter coastal waters when they reach approximately 20-25 cm 

carapace length. Coral reefs are widely recognized as the resident foraging habitat of juveniles, 

subadults and adults. This habitat association is undoubtedly related to their diet of sponges, 

which need solid substrate for attachment. The ledges and caves of the reef provide shelter for 

resting both during the day and night. Hawksbills are also found around rocky outcrops and high 

energy shoals, which are also optimum sites for sponge growth. Hawksbills are also known to 

inhabit mangrove-fringed bays and estuaries, particularly along the eastern shore of continents 

where coral reefs are absent. In Texas, juvenile hawksbills are associated with stone jetties. 

Hawksbills utilize both low- and high-energy nesting beaches in tropical oceans of the world. 

Both insular and mainland nesting sites are known. Hawksbills will nest on small pocket 

beaches, and, because of their small body size and great agility, can traverse fringing reefs that 

limit access by other species. They exhibit a wide tolerance for nesting substrate type. Nests are 

typically placed under vegetation. 

It is estimated that hawksbills recruited into the reef environment at 35 cm in length would begin 

breeding 31 years later. However, the time required to reach 35 cm in length is unknown. As a 

result, actual age at sexual maturity is not known. 

Distribution and Abundance: 

The hawksbill occurs in tropical and subtropical seas of the Atlantic, Pacific and Indian Oceans. 

The species is widely distributed in the Caribbean Sea and western Atlantic Ocean, with 

representatives of at least some life history stages regularly occurring in southern Florida and the 

northern Gulf of Mexico (especially Texas); in the Greater and Lesser Antilles; and along the 

Central American mainland south to Brazil. Within the United States, hawksbills are most 

common in Puerto Rico and its associated islands, and in the U.S. Virgin Islands. In the 

continental U.S., the species is recorded from all the gulf states and from along the eastern 

seaboard as far north as Massachusetts, with the exception of Connecticut, but sightings north of 

Florida are rare. 

Hawksbills are observed in Florida with some regularity on the reefs off Palm Beach County, 

where the warm Gulf Stream current passes close to shore, and in the Florida Keys. Texas is the 

only other state where hawksbills are sighted with any regularity. Most sightings involve 

posthatchlings and juveniles. These small turtles are believed to originate from nesting beaches 

in Mexico. 

Nesting within the southeastern United States occurs principally in Puerto Rico and the U.S. 

Virgin Islands, the most important sites being Mona Island and Buck Island. Nesting also occurs 

on other beaches of St. Croix, and on Culebra Island, Vieques Island, mainland Puerto Rico, St. 

47
 
Endangered Species Act Biennial Report to Congress 

John and St. Thomas. Within the continental United States, nesting is restricted to the southeast 

coast of Florida and Florida Keys. 

In the U.S. Pacific Ocean, there have been no hawksbill sightings off the west coast. Hawksbills 

have been observed in the Gulf of California as far as 29/N, throughout the northwestern states 

of Mexico, and south along the Central and South American coasts to Columbia and Ecuador. In 

the Hawaiian Islands, nesting occurs in the main islands, primarily on several small sand 

beaches on the Islands of Hawaii and Molokai. Two of these sites are at a remote location in the 

Hawaii Volcanos National Park. 

Major Impacts/Threats in the Nesting Environment: 

•	 The greatest threat on nesting beaches is poaching. Poaching of hawksbill eggs is a 

serious problem in Puerto Rico, and also occurs at lower levels in St. Thomas and St. 

Croix. Adult females are still butchered for their tortiseshell, but the practice is 

decreasing with better enforcement. 

•	 Erosion of nesting beaches can result in loss of nesting habitat. However, natural 

processes of beach erosion are not generally a significant threat. 

•	 Fortification of beachfronts to protect property from erosion can cause the loss of a dry 

nesting beach. It can also prevent females from getting to nesting sites and wash out 

nests. Beach nourishment buries nests and disturbs nesting turtles. Nourishment also 

results in heavy machinery, pipelines, increased human activity and artificial lighting on a 

project beach. This can create barriers for nesting sea turtles emerging from the ocean, 

preventing them from building nests, and it also disturbs nesting turtles on the beach. 

•	 Removal of sand for construction aggregate or renourishment of other beaches is a 

serious threat throughout the Caribbean. Sand removed from above the tide line is 

replaced very slowly from subtidal areas, a process which can take decades. Subtidal sand 

removal results in beach sand moving offshore. 

•	 Most nesting beaches are in private hands, and many of these have been developed. 

Development and landscaping of these nesting beaches can create impediments for 

nesting turtles. In addition, exotic plants such as sea oats can damage or destroy nests 

through root action. 

•	 Artificial lighting can cause disorientation or misorientation of both adults and hatchlings. 

Turtle hatchlings are attracted to light, ignoring or coming out of the ocean to go towards 

a light source, increasing their chances of death or injury. In addition, as nesting females 

avoid areas with intense lighting, highly developed areas may cause problems for turtles 

trying to nest. 

•	 Mechanical raking can result in heavy machinery repeatedly moving across a nest and 

compacting sand as well as causing tire ruts which may hinder or trap hatchlings. Rakes 

can penetrate the surface and disturb or uncover a nest. Disposing of debris on the high 

beach can cover nests and may alter nest temperature. 

•	 The most serious threat of nighttime use of a beach is the disturbance of nesting females. 

48
 
Endangered Species Act Biennial Report to Congress 

Heavy utilization of nesting beaches by humans may also result in lowered hatchling 

success due to sand compaction. 

•	 The use of off-road vehicles on beaches is a serious problem in many areas. It may result 

in decreased hatchling success due to sand compaction, or directly kill hatchlings. Tire 

ruts may also interfere with the ability of hatchlings to get to the ocean. 

•	 A variety of natural and introduced predators such as hogs, mongooses, ghost crabs and 

ants prey on hawksbill eggs and hatchlings. 

Major Impacts/Threats in the Marine Environment : 

•	 The extent to which hawksbills are killed or debilitated after becoming entangled in 

marine debris are unknown, but it is believed to be a serious and growing problem. 

Hawksbills have been reported entangled in monofilament gill nets, "fish nets", fishing 

line and rope. 

•	 Hawksbill turtles eat a wide variety of debris such as plastic bags, plastic and styrofoam 

pieces, tar balls, balloons and plastic pellets. Effects of consumption include interference 

in metabolism or gut function, even at low levels of ingestion, as well as absorption of 

toxic byproducts. 

•	 Incidental catch during fishing operations is an unquantified and potentially significant 

source of mortality. Gill nets, longlines and shrimp trawls all take turtles in Gulf of 

Mexico waters. In Puerto Rico, hawksbills are captured by a variety of fishing gear, 

including driftnets, gillnets, seines and spearguns. Gillnets and seines are widely deployed 

and are a particularly serious problem; these nets are sometimes set specifically for 

turtles. 

•	 In areas where recreational boating and ship traffic is intense, propeller and collision 

injuries are not uncommon. 

•	 In Puerto Rico, damage to coral reefs and other shallow water benthic systems from 

sedimentation and siltation has not been assessed as yet, but is known to be a serious 

problem in some areas, with some coral reefs completely destroyed by siltation. 

•	 Pesticides, heavy metals and PCB's have been detected in turtles and eggs, but their effect 

is unknown. 

•	 Raw sewage in Puerto Rico and the U.S. Virgin Islands has been released directly into 

nearshore waters. While a regional treatment plant has just been completed in Puerto 

Rico, monitoring has not been initiated. 

•	 The illegal take of hawksbills at sea has not yet been fully quantified, but it is a 

continuing problem. 

•	 Marine turtles are at risk when encountering an oil spill. Respiration, skin, blood 

chemistry and salt gland functions are affected. 

•	 The hawksbill's dependence on coral reefs for shelter and food link its well-being to the 

condition of reefs. Destruction of reefs from vessels anchoring, striking or grounding is a 

growing problem. Cruiseships and yachts are destroying portions of coral reefs with their 

anchors and anchor chains in the US Virgin Islands, Puerto Rico, the British Virgin 

49
 
Endangered Species Act Biennial Report to Congress 

Islands, Belize and elsewhere. There is also damage from recreational, diving and fishing 

boats anchoring indiscriminately on reefs. 

•	 International commerce in hawksbill shell (bekko) is the single most significant factor 

endangering hawksbill populations around the world. Japanese imports of raw bekko 

between 1970 and 1989 totalled 713,850 kg, representing more than 670,000 turtles; 

more than half the imports originated in the Caribbean and Latin America. While 

hawksbills are protected under CITES, trade continues for several reasons: 

a.	 Not all countries have ratified CITES; 

b.	 Some treaty signatories participate in trade by falsifying documents of origin; 

c.	 Some treaty signatories ignore the treaty and trade openly in hawksbills and 

hawksbill products; and 

d.	 Some treaty signatories have exercised their right to take exemption to treaty 

provisions as they affect sea turtles. 

•	 In nearshore waters, hawksbills are periodically captured in the cooling water intakes of 

industrial facilities. In addition, illegal use of explosives for fishing is a concern, 

especially off the southeast coast of Puerto Rico. 

Population Status 

Population 

Name 

Status Population 

Trend 

Population 

estimate 

Critical Habitat 

Rangewide Endangered Decreasing Unknown Designated 

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Endangered Species Act Biennial Report to Congress 

Designated Critical Habitat for Atlantic Hawksbill Turtles 

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Endangered Species Act Biennial Report to Congress 

Listed Species Status
 

Kemp’s Ridley Turtle: 

Lepidochelys kempii 

Listing Date: December 12, 1970 

The Kemp's ridley was listed as endangered throughout 

its range on December 2, 1970, and its status has 

remained unchanged. The Kemp's ridley population 

has declined since 1947 when an estimated 42,000 

females nested in one day to a nesting population of 

approximately 1000 in the mid 1980's. The decline of 

this species was primarily due to human activities including collection of eggs, fishing for 

juveniles and adults, killing adults for meat and other products, and direct take for indigenous 

use. In addition to these sources of mortality, Kemp's ridleys have been subject to high levels of 

incidental take by shrimp trawlers. Today, under strict protection, the population appears to be in 

the earliest stages of recovery. The increase can be attributed to two primary factors: full 

protection of nesting females and their nests in Mexico, and the requirement to use turtle 

excluder devices (TEDs) in shrimp trawls both in the United States and Mexico. 

Species Biology 

The Kemp's ridley and olive ridley turtles are the smallest of all extant sea turtles, with the 

weight of an adult generally being less than 45 kg and the straight carapace length around 65 cm. 

Adult Kemp's ridleys' shells are almost as wide as long. Coloration changes significantly during 

development from the grey-black carapace and plastron of hatchlings to the lighter grey-olive 

carapace and cream-white or yellowish plastron of adults. There are two pairs of prefrontal scales 

on the head, five vertebral scutes, five pairs of coastal scutes and generally twelve pairs of 

marginals on the carapace. In each bridge adjoining the plastron to the carapace, there are four 

scutes, each of which is perforated by a pore. This is the external opening of Rathke's gland 

which secretes a substance of unknown (possibly a pheromone) function. Males resemble the 

females in size and coloration. Secondary sexual characteristics of male sea turtles include a 

longer tail, more distal vent, recurved claws and, during breeding, a softened mid-plastron. Eggs 

are 34-45 mm in diameter and 24-40 g in weight. Hatchlings range from 42-48 mm in straight 

line carapace length, 32-44 mm in width and 15-20 g in weight. 

Neonatal Kemp's ridleys feed on the available sargassum and associated infauna or other 

epipelagic species found in the Gulf of Mexico. In post-pelagic stages, the ridley is largely a 

crab-eater, with a preference for portunid crabs. Age at sexual maturity is not known, but is 

52
 
Endangered Species Act Biennial Report to Congress 

believed to be approximately 7-15 years, although other estimates of age at maturity range as 

high as 35 years. 

Distribution and Abundance: 

The major nesting beach for Kemp's ridleys is on the northeastern coast of Mexico. This location 

is near Rancho Nuevo in southern Tamaulipas. The species occurs mainly in coastal areas of the 

Gulf of Mexico and the northwestern Atlantic Ocean. 

Major Impacts/Threats in the Nesting Environment: 

•	 Threats to the nesting beach in Mexico are presently few, but potentially serious. Human 

population growth and increasing developmental pressure will result in increased threats 

to the nesting beach. Only the central part of the prime nesting area is protected by 

Mexican presidential decree. A primary concern is human encroachment and access along 

the entire nesting area. However, the wording of the Mexican decree is vague and 

construction of commercial fishing facilities proceeded in 1987 immediately adjacent to 

the main turtle camp at Rancho Nuevo. Occasionally plans for massive expansion of La 

Pesca (just to the north of the nesting area) as a fishing center or dredging of the Gulf 

Intercoastal Waterway from Brownsville, Texas to Barra del Tordo (in the south part of 

the nesting beach) are reported. These plans are alarming because of the assuredly 

detrimental and possibly disastrous effects that they could have on the nesting population 

if they were to be completed. 

•	 A threat resulting from management practices at Ranch Nuevo is relocating all of the 

nests in one corral to prevent poaching and predation. This concentration makes the eggs 

more susceptible to reduced viability from the manipulation, disease vectors and 

inundation. 

Major Impacts/Threats in the Marine Environment 

•	 It is estimated that before the implementation of TEDs, the commercial shrimp fleet 

killed 500-5000 Kemp's ridleys each year. Besides shrimp trawls, Kemp's ridleys have 

been taken in pound nets, trawls, gill nets, hook and line, crab traps, and longlines. 

Beginning in 1976, the U.S. and Mexican governments agreed to phase out U.S. 

shrimping in Mexican waters by 1979. U.S. shrimp vessels continued to illegally operate 

off Mexico through the mid 1980s. The Mexican shrimp fleet has declined and consists of 

only approximately 600 vessels, many of which do not operate. Also since 1978, Mexico 

has closed the nearshore waters off Rancho Nuevo to fishing during the nesting season. 

However, this closure has not been strictly enforced. 

•	 The Gulf of Mexico is an area of high density offshore oil extraction with chronic 

low-level spills and occasional massive spills. The two primary feeding grounds for adult 

Kemp's ridley turtles in the northern and southern Gulf of Mexico are both near major 

areas of near shore and offshore oil exploration and production. The nesting beach at 

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Endangered Species Act Biennial Report to Congress 

Rancho Nuevo is also vulnerable and has been affected by oil spills. 

•	 The vast amount of floating debris in the Gulf of Mexico constitutes an increasingly 

serious threat to Kemp's ridley turtles of all ages. Plastics, monofilament, discarded 

netting and many other waste items are either eaten by Kemp's ridleys or become death 

traps when the turtles become entangled. Ingestion of plastic, rubber, fishing line and 

hooks, tar, cellophane, rope and string, wax, styrofoam, charcoal, aluminum cans and 

cigarette filters has occurred in sea turtles. 

•	 NMFS is currently analyzing stranding data and available necropsy information to 

determine the magnitude of debris ingestion and entanglement. 

•	 Dredging operations affect Kemp's ridley turtles through incidental take and by degrading 

the habitat. Incidental take of ridleys has been documented with hopper dredges. In 

addition to direct take, channelization of the inshore and nearshore areas can degrade 

foraging and migratory habitat through spoil dumping, degraded water quality/clarity and 

altered current flow. 

Population Status 

Population 

Name 

Status Population 

Trend 

Population 

estimate 

Critical Habitat 

Rangewide Endangered Increasing 954 nesting 

females4 

4

Number of females nesting in 1997 based on 2.5 nests/female/year. 

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Endangered Species Act Biennial Report to Congress 

Listed Species Status 

Leatherback Turtle: Dermochelys coriacea 

Listing Date: 06/02/70 

The leatherback turtle was listed as endangered 

throughout its range on June 2, 1970. Nesting populations 

of leatherback turtles are especially difficult to discern 

because the females frequently change beaches. However, 

current estimates are that 20,000-30,000 female 

leatherbacks exist worldwide. 

Leatherbacks do not nest frequently enough in the United 

States to assess an accurate trend. The recovery plan for the leatherback turtle concludes that 

nesting trends in the United States appear stable, but the population faces significant threats from 

incidental take in commercial fisheries and marine pollution. 

Populations have declined in Mexico, Costa Rica, Malaysia, India, Sri Lanka, Thailand, Trinidad, 

Tobago, and Papua New Guinea. Leatherbacks are seriously declining at all major nesting 

beaches throughout the Pacific. The decline is dramatic along the Pacific coasts of Mexico and 

Costa Rica and coastal Malaysia. Nesting along the Pacific coast of Mexico declined at an annual 

rate of 22% over the last 12 years, and the Malaysian population represents 1% of the levels 

recorded in the 1950s. The collapse of these nesting populations was precipitated by a 

tremendous overharvest of eggs, direct harvest of adults, and incidental mortality from fishing. In 

the Atlantic and Carribean, the largest nesting assemblages are found in the U.S. Virgin Islands, 

Puerto Rico, and Florida. Nesting data for these locations have been collected since the early 

1980's and indicate that the annual number of nests is likely stable; however, information 

regarding the status of the entire leatherback population in the Atlantic is lacking. Nesting 

activity has also declined in French Guiana due to erosion of nesting beaches, the population 

appears to have shifted to Surinam, where annual numbers of nests have risen from less than 100 

in 1967 to 5,565 in 1977 and 9,816 in 1987. Habitat destruction, incidental catch in commercial 

fisheries, the harvest of eggs and flesh are the greatest threats to the survival of the leatherback. 

Species Biology 

The leatherback is the largest living turtle, and is so distinctive as to be placed in a separate 

taxonomic family, Dermochelyidae. The carapace is distinguished by a rubber-like texture, about 

4 cm thick, and made primarily of tough, oil-saturated connective tissue. No sharp angle is 

formed between the carapace and the plastron, resulting in the animal being somewhat barrel55
 
Endangered Species Act Biennial Report to Congress 

shaped. The average curved carapace length for adult turtles is 155 cm and weight ranges from 

200-700 kg. Hatchlings are dorsally mostly black and are covered with tiny scales; the flippers 

are margined in white, and rows of white scales appear as stripes along the length of the back. 

Hatchlings average 61.3 mm long and 45.8 g in weight. In the adult, the skin is black and 

scaleless. The undersurface is mottled pinkish-white and black. The front flippers are 

proportionally longer than in any other sea turtle, and may span 270 cm in an adult. In both adults 

and hatchlings, the upper jaw bears two tooth-like projections at the premaxillary-maxillary 

sutures. Age at sexual maturity is unknown. 

Distribution and Abundance 

The leatherback turtle's range extends from Cape Sable, Nova Scotia, south to Puerto Rico and 

the U.S. Virgin Islands. Critical habitat for the leatherback includes the waters adjacent to Sandy 

Point, St. Croix, U.S. Virgin Islands, up to and inclusive of the waters from the hundred fathom 

curve shoreward to the level of mean high tide with boundaries at 17/42'12" N and 64/50'00" W. 

Nesting occurs from February - July with sites located from Georgia to the U.S. Virgin Islands. 

Leatherbacks migrate from southern nesting beaches along the Atlantic coast in the Spring to 

nutrient rich waters in the Gulf of Maine and Canada and conversely migrate south in the late 

Fall. 

Leatherbacks are commonly seen by fishermen in Hawaiian offshore waters, generally beyond 

the 100-fathom curve but within sight of land. Sightings often take place off the north coast of 

Oahu and the Kona coast of Hawaii. North of the Hawaiian Islands, a high seas aggregation of 

leatherbacks is known to occur at 35/-45/N, 175/-180/W. 

Major Impacts/Threats in the Nesting Environment 

•	 Historically, leatherback turtles were rarely taken for their meat. However, a few have 

been killed in recent years. In Puerto Rico, adults are occasionally taken for meat and oil. 

In addition, the poaching of eggs from nests continues at low levels in the U.S. Virgin 

Islands and is widespread in Puerto Rico. 

•	 Leatherback turtles prefer to nest on open beaches. However, these beaches are prone to 

erosion, causing egg loss. Nests are also lost to hurricanes. 

•	 Development of beachfronts results in fortification to protect property from erosion, 

resulting in loss of a dry nesting beach. It can also prevent females from getting to nesting 

sites and wash out nests. 

•	 Beach nourishment impacts turtles by burial of nests, disturbance to nesting turtles, and 

changes sand compaction and temperature which may affect embryo development. 

•	 Artificial lights can cause disorientation or misorientation of both adults and hatchlings. 

Turtles are attracted to light, ignoring or coming out of the ocean to go towards a light 

source. This increases their chances of death or injury. In addition, as nesting females 

avoid areas with intense lighting, highly developed areas may cause problems for turtles 

trying to nest. 

56
 
Endangered Species Act Biennial Report to Congress 

•	 Mechanical raking can result in heavy machinery repeatedly moving across a nest and 

compacting sand as well as causing tire ruts which may hinder or trap hatchlings. Rakes 

can penetrate the surface and disturb or uncover a nest. Disposing of debris on the high 

beach can cover nests and may alter nest temperature. 

•	 The most serious threat of nighttime use of a beach is the disturbance of nesting females. 

Heavy utilization of nesting beaches by humans may also result in lowered hatchling 

success due to sand compaction. 

•	 The placement of physical obstacles on a beach can hamper or deter nesting attempts as 

well as interfere with incubating eggs and the movement of hatchlings to the sea. 

•	 The use of off-road vehicles on beaches is a serious problem in many areas. It may result 

in decreased hatchling success due to sand compaction, or directly kill hatchlings. Tire 

ruts may also interfere with the ability of hatchlings to get to the ocean. 

Major Impacts/Threats in the Marine Environment 

•	 Leatherbacks become entangled in longlines, fish traps, buoy anchor lines and other ropes 

and cables. This can lead to serious injuries and/or death by drowning. The setting of 

"large mesh nets suitable for turtling" is common in the waters of Puerto Rico. Although 

the practice was outlawed in 1984, it still continues. The nets are intended for hawksbills 

and green turtles, but leatherbacks occasionally become entangled. 

•	 Leatherback turtles eat a wide variety of marine debris such as plastic bags, plastic and 

styrofoam pieces, tar balls, balloons and plastic pellets. Effects of consumption include 

interference in metabolism or gut function, even at low levels of ingestion, as well as 

absorption of toxic byproducts. NMFS is currently analyzing stranding data and available 

necropsy information to determine the magnitude of debris ingestion. 

•	 It is estimated that even with TEDs, the offshore commercial shrimp fleet is anticpated to 

capture about 640 leatherbacks a year. The use of TEDs is not expected to reduce 

leatherback captures and mortality significantly, because TEDs are generally incapable of 

passing adult leatherbacks through the exit opening. However, beginning in 1995, NMFS 

established a Leatherback Conservation Zone to restrict shrimp trawl activities from off 

the coast of Cape Canaveral, Florida, to the North Carolina/Virginia border. This 

provides for short-term closures when high concentrations of normally pelagically 

distributed leatherbacks are recorded in more coastal waters where the shrimp fleet 

operates. This measure is necessary because, due to their size, adult leatherbacks are 

larger than the escape openings of most NMFS-approved TEDs. 

•	 Leatherbacks are vulnerable to boat collisions and strikes, particularly when in waters 

near shore. It is not known if open ocean collisions with large ships occur. 

•	 Marine turtles are at risk when encountering an oil spill. Respiration, skin, blood 

chemistry and salt gland functions are affected. 

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Endangered Species Act Biennial Report to Congress 

Population Status
 

Population 

Name 

Status Population 

Trend 

Population 

estimate 

Critical Habitat 

Rangewide Endangered Decreasing unknown5 Designated 

Designated Critical Habitat for Atlantic Leatherback Turtles 

5

Population trend for the Pacific leatherback is declining, while the Atlantic leatherback are stable. 

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Endangered Species Act Biennial Report to Congress 

Listed Species Status 

Loggerhead Turtle: Caretta caretta 

Listing Date: 06/02/70 

The loggerhead turtle was listed as threatened 

throughout its range on June 2, 1970, and its status 

has not changed. Most recent evidence suggests that 

the number of nesting females in South Carolina 

and Georgia may be declining, while the number of 

nesting females in Florida appears to be stable. 

Four nesting subpopulations of loggerheads in the 

western North Atlantic have been identified based 

on genetic research: (1) the Northern Subpopulation, producing approximately 6,200 nests/year 

from North Carolina to Northeast Florida; (2) the South Florida Subpopulation, occurring from 

just north of Cape Hatteras on the east coast of Florida and extending up to Naples on the west 

coast. The Northern Subpopulation declined through the mid 1980s and thereafter a trend is not 

detected. Recent surveys of South Carolina nesting beaches (where more than 30% of the nesting 

of the Northern Subpopulation occurs) indicate a downward trend and thus the subpopulation is 

stable or declining. The South Florida Subpopulation appears to have shown significant increases 

over the last 25 years, suggesting the population is recovering, although the trend could not be 

detected over the most recent 7 years of nesting. An increase in the numbers of adult loggerheads 

has been reported in recent years in Florida waters without a concomitant increase in benthic 

immatures. These data may forecast limited recruitment to South Florida nesting beaches in the 

future. Since loggerheads take approximately 20-30 years to mature, the effects of decline in 

immature loggerheads might not be apparent on nesting beaches for decades. The recovery team 

concluded that nesting trends for the loggerhead are generally declining. The most significant 

threats tot he loggerhead populations is coastal development, commercial fisheries, and pollution. 

Loggerhead populations in Honduras, Mexico, Colombia, Israel, Turkey, Bahamas, Cuba, 

Greece, Japan, and Panama have been declining. This decline continues and is primarily 

attributed to shrimp trawling, coastal development, increased human use of nesting beaches, and 

pollution. Loggerheads are the most abundant species in U.S. coastal waters, and are often 

captured incidental to shrimp trawling. Shrimping is thought to have played a significant role in 

the population declines observed for the loggerhead. 

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Endangered Species Act Biennial Report to Congress 

Species Biology 

Adults and sub-adults have a reddish-brown carapace. Scales on the top and sides of the head and 

top of the flippers are also reddish-brown, but have yellow borders. The neck, shoulders and limb 

bases are dull brown on top and medium yellow on the sides and bottom. The plastron is also 

medium yellow. Adult average size is 92 cm straight carapace length; average weight is 115 kg. 

Hatchlings are dull brown in color. Average size at hatching is 45 mm long; average weight is 20 

g. Maturity is reached at between 16-40 years. Mating takes place in late March-early June, and 

eggs are laid throughout the summer. 

Distribution and Abundance 

Loggerheads are circumglobal, inhabiting continental shelves, bays, estuaries, and lagoons in 

temperate, subtropical, and tropical waters. In the Atlantic, the loggerhead turtle's range extends 

from Newfoundland to as far south as Argentina. During the summer, nesting occurs in the lower 

latitudes, but not in the tropics. The primary Atlantic nesting sites are along the east coast of 

Florida, with additional sites in Georgia, the Carolinas, and the Gulf Coast of Florida. In the 

eastern Pacific, loggerheads are reported as far north as Alaska, and as far south as Chile. 

Occasional sightings are also reported from the coast of Washington, but most records are of 

juveniles off the coast of California. Southern Japan is the only known breeding area in the North 

Pacific. 

Major Impacts/Threats in the Nesting Environment 

•	 In the United States, killing of nesting loggerheads is infrequent. However, in a number 

of areas, egg poaching is common. 

•	 Erosion of nesting beaches can result in loss of nesting habitat. 

•	 Development of beachfronts results in fortification to protect property from erosion, 

resulting in loss of a dry nesting beach. It can also prevent females from getting to nesting 

sites and wash out nests. 

•	 Beach nourishment impacts turtles by burial of nests, disturbance to nesting turtles, and 

changes in sand compaction and temperature which may affect embryo development. 

•	 Artificial lighting can cause disorientation or misorientation of both adults and hatchlings. 

Turtles are attracted to light, ignoring or coming out of the ocean to go towards a light 

source, increasing their chances of death or injury. In addition, as nesting females avoid 

areas with intense lighting, highly developed areas may cause problems for turtles trying 

to nest. 

•	 Repeated mechanical raking of nesting beaches by heavy machinery can result in compact 

sand and causes tire ruts which may hinder or trap hatchlings. Rakes can penetrate the 

surface and disturb or uncover a nest. Disposing of debris on the high beach can cover 

nests and may alter nest temperature. 

•	 A serious threat of nighttime use of a beach is the disturbance of nesting females. Heavy 

utilization of nesting beaches by humans may also result in lowered hatchling success due 

60
 
Endangered Species Act Biennial Report to Congress 

to sand compaction. 

•	 The placement of physical obstacles on a beach can hamper or deter nesting attempts as 

well as interfere with incubating eggs and the sea approach of hatchlings. 

•	 The use of off-road vehicles on beaches is a serious problem in many areas. It may result 

in decreased hatchling success due to sand compaction, or directly kill hatchlings. Tire 

ruts may also interfere with the ability of hatchlings to get to the ocean. 

•	 The invasion of a nesting site by non-native beach vegetation can lead to increased 

erosion and destruction of a nesting habitat. Trees shading a beach can also change nest 

temperatures, altering the natural sex ratio of the hatchlings. 

Major Impacts/Threats in the Marine Environment 

•	 Dredging can destroy resting or foraging habitats. The use of hopper dredges can also kill 

turtles caught in dragheads. 

•	 Loggerhead turtles eat a wide variety of marine debris such as plastic bags, plastic and 

styrofoam pieces, tar balls, balloons and raw plastic pellets. Effects of consumption 

include interference in metabolism or gut function, even at low levels of ingestion, as 

well as absorption of toxic byproducts. NMFS is currently analyzing stranding data and 

available necropsy information to determine the magnitude of debris ingestion and 

entanglement. 

•	 Commercial Fishing: 

•	 5,000-50,000 loggerheads each year. Most turtles killed are juveniles and subadults. Inshore catch and mortality for shrimp trawlers is not known, but is 

thought to be significant. Bluefish, croaker and flounder trawl fishing are also a 

serious threat. 

•	 Turtles are taken by gillnet fisheries in the Atlantic and Gulf of Mexico, but the 

number is currently not known. 

•	 Several thousand vessels are involved in hook and line fishing for various coastal 

species. The capturing of turtles is not uncommon, but the number is currently not 

known. 

•	 Pound net fisheries are primarily a problem in waters off of Virginia and North 

Carolina, however generally turtles are released alive. 

•	 From 1978-1981, 330 turtles were captured in the Atlantic and Gulf of Mexico 

EEZ in the Japanese tuna longline fishery. Due to expansion of this fishery, it may 

have a large impact on turtle recovery. 

•	 Loggerhead turtles are vulnerable to entanglement in trap fishery lines, and 

subsequent drowning. The impact on the population has not been determined. 

•	 In areas where recreational boating and ship traffic is intense propeller and collision 

injuries are not uncommon. 

•	 Sea turtles are at risk when encountering an oil spill. Respiration, skin, blood chemistry 

61
 
Endangered Species Act Biennial Report to Congress 

and salt gland functions are affected. 

•	 Pesticides, heavy metals and PCB's have been detected in turtles and eggs, but the effect 

on them is unknown. 

•	 Marina and dock development can cause foraging habitat to be destroyed or damaged. It 

also leads to increased boat traffic, increasing the risk of turtle/vessel collisions. 

•	 Turtles have been caught in saltwater intake systems of coastal power plants. The 

mortality rate is estimated at 2%. 

•	 Underwater explosions can kill or injure turtles, and may destroy or damage habitat. 

•	 The effects of offshore lights are not known. They may attract hatchlings and interfere 

with proper offshore orientation, increasing the risk from predators. 

•	 Turtles get caught in discarded fishing gear. The number affected is unknown, but 

potentially significant. 

•	 Illegal harvesting of loggerhead turtles is uncommon in the U.S. and Caribbean. No 

estimates of take exist. 

Population Status 

Population Name Status Population 

Trend 

Population 

Estimate 

Critical Habitat 

Range-wide Threatened Decreasing unknown 

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Endangered Species Act Biennial Report to Congress 

Listed Species Status 

Olive Ridley Turtle: Lepidochelys 

olivacea 

Listing Date: 07/28/78 

The olive ridley turtle was listed as endangered for the 

"Mexican nesting population" and threatened for all other 

populations on July 28, 1978. Since listing, there has 

been a decline in abundance of this species, and it has 

been recommended that the olive ridley for the Western 

Atlantic be reclassified as endangered. The need for this 

classification is based on continued direct and incidental take, particularly in shrimp trawl nets. 

The western North Atlantic (Surinam and adjacent areas) nesting population has declined more 

than 80 percent since 1967. Declines are also documented for Playa Nancite, Costa Rica, 

however other nesting populations along the Pacific coast of Mexico and Costa Rica appear 

stable or increasing. In the Indian Ocean, Gahirmatha located in the Bhitarkanika Wildlife 

Sanctuary, India, supports perhaps the largest nesting population with an average of 398,000 

females nesting in a given year. This population continues to be threatened by nearshore trawl 

fisheries. Direct harvest of adults and eggs, incidental capture in commercial fisheries and loss 

of nesting habitat are main concerns regarding the recovery of this species. 

Species Biology 

The olive ridley is a small, hard-shelled marine turtle, one of the two species of the genus 

Lepidochelys , and a member of the family Cheloniidae. The species may be identified by the 

uniquely high and variable numbers of vertebral and costal scutes. Although some individuals 

have only five pairs of costals (the number shown by almost all individuals of the congener 

Lepidochelys kempii), in nearly all cases some division of costal scutes occurs, so that as many as 

six to nine pairs may be present. Division of the "standard" scutes occurs from the rear of the 

carapace, so that a specimen with, say, seven pairs of costals shows division of the homologs of 

costals IV and V. Asymmetry in the number of costal scutes is frequent. 

In addition to the division of the costal scutes, the vertebral scutes also show frequent division, as 

do the scales on the dorsal surface of the head. The prefrontal scales, however, typically number 

two pairs. The carapace is wide in subadults and adults, although less so than that of L. kempii. In 

anterior profile it is typically elevated and flat-topped, with flat, sloping sides. The plastron is 

large, with the usual six pairs of large scutes and sometimes a small intergular and interanal also. 

The inframarginals typically number four on each side, each of which is perforated by a pore 

63
 
Endangered Species Act Biennial Report to Congress 

located towards its posterior margin. The head is relatively large, as compared with that of 

Chelonia or Eretmochelys, but is smaller than that of adult Caretta, and slightly smaller than that 

of L. kempii. 

The skull of L. olivacea differs from that of L. kempii in many ways. The orbit is consistently 

larger, the width across the pterygoids is consistently less, and the alveolar ridges are sharp and 

are only evident on the rhamphothecae, not on the underlying maxillary-palatine sutural area. 

There are also numerous differences between the lower jaws of the two species, as follows: 

1.	 the entire bony alveolar surface of L. olivacea is flat (rather strongly concave in L. 

kempii) 

2.	 the overall depth of the jaw of L. olivacea is somewhat less than that of L. kempii 

3.	 The tip of the coronoid bone, that provides attachment for the temporal muscle closing 

the jaw, is rounded off in L. olivacea (bluntly pointed in L. kempii) 

4.	 the dorsal mandibular vacuity is relatively larger in L. olivacea that in L. kempii 

5.	 the articular surfaces of the mandible of L. olivacea tend to be directed upward (directed 

more posteriorly in L. kempii) 

6.	 the bones comprising the articular surfaces (the articular, pre-articular, and angular) are 

loosely sutured in adult L. olivacea. 

In size, female olive ridleys in Surinam range in carapace length from 62 to 74 cm; in Pacific 

Honduras from 58 to 74 cm; and in Pacific Mexico from 56 to 78 cm. 

Geographic variation in olive ridleys is subtle, and no subspecies are currently recognized. 

However, the number of costal scutes apparently varies from one area to another, specimens with 

only five pairs of costals being somewhat more abundant in the eastern Pacific than elsewhere. In 

addition, overall carapace coloration is typically somewhat lighter in the western Atlantic than in 

the eastern Pacific. and the shell is typically more elevated in the eastern Pacific than elsewhere. 

The most dramatic aspect of the life history of the olive ridley is the habit of forming great 

nesting aggregations, generally known as "arribadas," sometimes as "arribazones" or "morrias". 

Although not every adult olive ridley participates in these arribadas, the vast majority of them do. 

Formerly these nesting concentrations occurred at several beaches along the Pacific coast of 

Mexico, including Piedra del Tlacoyunque, Bahia Chacahua, and El Playon de Mismaloya, but in 

recent years the Mexican arribadas have been largely restricted to La Escobilla, although smaller 

nesting concentrations have been reported from Morro Ayuta. In Costa Rica, a major nesting 

aggregation is found at Ostional, on the Nicoya Peninsula, and smaller arribadas occur at 

Nancite, in the Santa Rosa National Park. Smaller arribadas also occur in Nicaragua at La Flor 

and Chacocente and at several localities in Panama. In the Indian Ocean, four arribada sites have 

64
 
Endangered Species Act Biennial Report to Congress 

been reported in the Indian State of Orissa, the most important being Gahirmatha Beach. In the 

Atlantic, only small arribadas, numbering at most a few hundred animals per night, have been 

reported from a single locality. 

Arribadas may be precipitated by such climatic events as a strong offshore wind, or by certain 

phases of the moon and tide, but there is a major element of unpredictability at all arribada sites. 

This unpredictability, and the apparent ability of gravid females to wait for weeks while holding 

fully-shelled eggs, may be an important aspect of the survival advantage of arribada-formation, a 

phenomenon usually interpreted as one that evolved as a predator-saturation device. 

Individual olive ridleys may nest one, two or three times per season, typically producing 100-110 

eggs on each occasion. The internesting interval is variable, but for most localities it is 

approximately 14 days for solitary nesters and 28 days for arribada nesters. The genus is also 

unique in that ridleys of both species commonly, and probably typically, nest each year, without 

intervening non-breeding seasons as shown by dermochelyids and other cheloniids. The ridleys 

nesting in an arribada could not be sustained by the productivity of immediately adjacent marine 

ecosystems, and the species is indeed migratory. Recent investigations show that olive ridleys 

reside in oceanic habitats of the eastern Pacific Ocean during the non-reproductive portion of its 

life cycle. 

The overall distribution of the olive ridley shows interesting parallels with that of the utterly 

different leatherback turtle (Dermochelys coriacea). Both occupy oceanic habitats and both nest 

primarily on Pacific shores of the American tropics and in the Guianas, in moderate numbers in 

tropical West Africa, and in relatively small numbers elsewhere, both being extremely rare, for 

example, throughout Australia, or Pacific oceanic islands. 

Despite its abundance, there are surprisingly few data relating to the feeding habits of the olive 

ridley. However, those reports that do exist suggest that the diet in the western Atlantic and 

eastern Pacific includes crabs, shrimp, rock lobsters, jellyfish, and tunicates. In some parts of the 

world, it has been reported that the principal food is algae. 

Distribution and Abundance 

The range of the olive ridley is essentially tropical. In the eastern Pacific nesting takes place from 

southern Sonora, Mexico, south at least to Colombia. Non-nesting individuals occasionally are 

found in waters of the southwestern United States. They occur abundantly in Pacific Colombia 

and Ecuador, but only in small numbers in Peru and Chile. 

The olive ridley has been recorded occasionally from Galapagos waters, but it is essentially very 

rare throughout the islands of the Pacific, and indeed even in the western Pacific it is scarce 

everywhere, although widespread low-density nesting occurs. In the Indian Ocean it only 

65
 
Endangered Species Act Biennial Report to Congress 

achieves abundance in eastern India and Sri Lanka, although minor nesting occurs alongside the 

green turtles at Hawke's Bay, Pakistan, and some nesting also occurs in New Britain, 

Mozambique, Madagascar, peninsular Malaysia, and various other localities. 

In the Atlantic Ocean, the olive ridley occurs widely, but probably not in great abundance, in 

waters of West Africa, from about Mauritania southward at least to the Congo. In the western 

Atlantic, nesting formerly occurred abundantly in eastern Surinam, as well as in western French 

Guiana and northwestern Guyana. Non-nesting individuals occur regularly as far west as Isla 

Margarita and Trinidad, but they rarely penetrate any further into the Caribbean than this. The 

species occurs in Brazil, and nests in the states of Bahia and Sergipe, but it seems to be rare. 

Population Status 

Because of the continued existence of several large arribadas, it is probable that the olive ridley 

is, in terms of absolute numbers of adult individuals in existence, the most abundant sea turtle 

species in the world. Nevertheless, there is evidence of downward trends at several arribada 

beaches. The various populations are under considerable stress, and the concentration of such a 

large proportion of the reproductive animals into a few arribadas may be a liability, not only in 

that such aggregation facilitates industrial-scale exploitation, as it has in Mexico as well as on the 

feeding grounds in Ecuador, but also because arribadas do not seem to be an efficient method of 

guaranteeing maximum reproductive efficiency. Indeed, at the relatively undisturbed arribada 

beach of Nancite, within Santa Rosa National Park, Costa Rica, it has been estimated that only 

about 5 % of eggs laid actually produce hatchlings. 

The number of ridleys nesting during an arribada is difficult to count, although methodologies to 

estimate arribada size have been developed that are useful if nesting is well supervised by 

competent biologists. On the other hand, estimates by laymen of numbers of turtles in a given 

arribada are probably so inaccurate as to be useless. Because nesting in successive years is 

commonplace for olive ridleys, and may well be the norm for the species, the erratic nesting 

population trend lines often shown by loggerhead or green turtle populations, that very rarely nest 

in successive years, are not shown by olive ridley populations. It is thus much easier and more 

justified to draw conclusions about overall ridley population trends from a few years of 

comprehensive nest counts than it is for those species with multi-year nesting cycles. 

Major Impacts/Threats to Olive Ridley Turtles 

•	 Pesticides, heavy metals and PCB's have been detected in turtles and eggs, but the effect 

on them is unknown. 

•	 Marine turtles are at risk when encountering an oil spill. Respiration, skin, blood 

chemistry and salt gland function are affected. 

•	 Olive ridley turtles eat a wide variety of marine debris such as plastic bags, plastic and 

styrofoam pieces, tar balls, balloons and raw plastic pellets. Effects of consumption 

66
 
Endangered Species Act Biennial Report to Congress 

include interference in metabolism or gut function, even at low levels of ingestion, as 

well as absorption of toxic byproducts. 

•	 In areas where recreational boating and ship traffic is intense, propeller and collision 

injuries are not uncommon. 

Population Status 

Population Name Status Population 

Trend 

Population 

Estimate 

Critical Habitat 

Range-wide Threatened Decreasing unknown 

Mexican Breeding 

population 

Endangered Increasing >350,0006 

6

Estimated number of nesting females at La Escobilla beach, Oaxaca, Mexico in 1996. 

67 
Endangered Species Act Biennial Report to Congress 

Listed Species Status
 

Chinook Salmon: Oncorhynchus 

tshawytscha 

Along the U.S. West Coast, there are 17 distinct 

groups, or evolutionarily significant units (ESUs), of 

chinook salmon, from southern California to the 

Canadian border and east to the Rocky Mountains. 

Snake River spring/summer chinook and Snake River 

fall chinook were listed as threatened species in 1992. 

In 1994, Sacramento River winter-run chinook were 

listed as endangered. In March 1998, two ESUs were proposed as endangered, five proposed as 

threatened, and the Snake River fall-run ESU was proposed to include fall chinook salmon 

populations in the Deschutes River. Details about these proposed ESUs are summarized below 

by population. 

Species Biology 

Chinook salmon belong to the family Salmonidae and are one of eight species of Pacific 

salmonids in the genus Oncorhynchus. Chinook salmon are easily the largest of any salmon, 

with adults often exceeding 40 pounds; individuals over 120 pounds have been reported. 

Chinook salmon are very similar to coho salmon in appearance while at sea (blue-green back 

with silver flanks), except for their large size, small black spots on both lobes of the tail, and 

black pigment along the base of the teeth. Chinook salmon are anadromous (adults migrate from 

a marine environment into the fresh water streams and rivers of their birth) and semelparous 

(spawn only once and then die). 

Chinook salmon stocks exhibit considerable variability in size and age of maturation, and at least 

some portion of this variation is genetically determined. The relationship between size and 

length of migration may also reflect the earlier timing of river entry and the cessation of feeding 

for chinook salmon stocks that migrate to the upper reaches of river systems. Body size, which is 

correlated with age, may be an important factor in migration and redd construction success. Roni 

and Quinn (1995) reported that under high density conditions on the spawning ground, natural 

selection may produce stocks with exceptionally large-sized returning adults. 

There are different seasonal “runs” (ie., spring, summer, fall, or winter) or modes in the 

migration of chinook salmon from the ocean to freshwater. These runs have been identified on 

the basis of when adult chinook salmon enter freshwater to begin their spawning migration. 

However, distinct runs also differ in the degree of maturation at the time of river entry, the 

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Endangered Species Act Biennial Report to Congress 

thermal regime and flow characteristics of their spawning site, and their actual time of spawning. 

Freshwater entry and spawning timing are believed to be related to local temperature and water 

flow regimes. 

Adult female chinook will prepare a spawning bed, called a redd, in a stream area with suitable 

gravel composition, water depth and velocity. The adult female chinook may deposit eggs in 4 

to 5 “nesting pockets” within a single redd. After laying eggs in a redd, adult chinook will guard 

the redd from 4 to 25 days before dying. Chinook salmon eggs will hatch, depending upon water 

temperatures, between 90 to 150 days after deposition. Eggs are deposited at a time to ensure 

that young salmon fry emerge during the following spring when the river or estuary productivity 

is sufficient for juvenile survival and growth. Juvenile chinook may spend from 3 months to 2 

years in freshwater after emergence and before migrating to estuarine areas as smolts, and then 

into the ocean to feed and mature. Coastwide, chinook salmon remain at sea for 1 to 6 years 

(more commonly 2 to 4 years), with the exception of a small proportion of yearling males (called 

jack salmon) which mature in freshwater or return after 2 or 3 months in salt water. 

Among chinook salmon, two distinct races have evolved. One race, described as a “stream-type” 

chinook, is found most commonly in headwater streams. Stream-type chinook salmon have a 

longer freshwater residency, and perform extensive offshore migrations before returning to their 

natal streams in the spring or summer months. Stream-type juveniles are much more dependent 

on freshwater stream ecosystems because of their extended residence in these areas. A streamtype life history may be adapted to areas that are more consistently productive and less 

susceptible to dramatic changes in water flow. At the time of saltwater entry, stream-type 

(yearling) smolts are much larger, averaging 73-134 mm depending on the river system, than 

their ocean-type (subyearling) counterparts and are therefore able to move offshore relatively 

quickly. Stream-type chinook salmon are found migrating far from the coast in the central North 

Pacific. 

The second race is called the “ocean-type” chinook, which is commonly found in coastal streams 

in North America. Ocean-type chinook typically migrate to sea within the first three months of 

emergence, but they may spend up to a year in freshwater prior to emigration. They also spend 

their ocean life in coastal waters. Ocean-type chinook salmon return to their natal streams or 

rivers as spring, winter, fall, summer, and late-fall runs, but summer and fall runs predominate. 

Ocean-type chinook salmon tend to utilize estuaries and coastal areas more extensively for 

juvenile rearing. The development of the ocean-type life history strategy may have been a 

response to the limited carrying capacity of smaller stream systems and unproductive watersheds, 

or a means of avoiding the impact of seasonal floods. Ocean-type chinook salmon tend to 

migrate along the coast. Populations of chinook salmon south of the Columbia River drainage 

appear to consist predominantly of ocean-type fish. 

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Endangered Species Act Biennial Report to Congress 

Distribution and Abundance 

Chinook salmon are found from the Bering Strait south to Southern California. Historically, they 

ranged as far south as the Ventura River, California. 

Major Threats and Impacts 

See section entitled "Major Threats and Impacts to Pacific Salmonids" as well as more specific 

information under each population summary. 

ESU Status 

ESU Name Status Listing 

Date 

Population 

Trend 

Last 5 years 

Population 

Estimate 

Mean # 1994-1998 

Critical 

Habitat 

Central Valley 

California, spring-run 

Proposed 

Endangered 

3/1998 Proposed 

Snake River Fall run Endangered 4/1992 stable 565 Designated 

Sacramento River 

Winter-run 

Endangered 1/1994 Designated 

Snake River 

Spring/Summer run 

Threatened 4/1992 decreasing 3,300 Designated 

Central Valley, fall/late 

fall-run 

Proposed 

Threatened 

3/1998 mixed 200,000 Proposed 

Southern Oregon & 

California Coastal 

Proposed 

Threatened 

3/1998 mixed 132,000 in Oregon Proposed 

Puget Sound Proposed 

Threatened 

3/1998 mixed 71,000 (spawning 

escapement) 

Proposed 

Lower Columbia River Proposed 

Threatened 

3/1998 decreasing 2,000 <1% historic 

abundance7 

Proposed 

Upper Willamette 

River 

Proposed 

Threatened 

3/1998 decreasing 1,8008 Proposed 

Upper Columbia River, 

Spring run 

Proposed 

Endangered 

3/1998 decreasing 7409 Proposed 

7

No data update since 1994 

8

Updates through 1996-1998 

9

Sum of escapement to tributaries; mean for 1991-1995 

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Endangered Species Act Biennial Report to Congress 

Population Name: Central Valley, California, Spring run 

Species Status: Proposed Endangered 

Trend: Declining 

Estimate: Average recent abundance is 2,000 fish, compared with 40,000 in 1940s 

ESU Distribution/Description: 

This ESU encompasses all naturally spawned populations of chinook (and their progeny) in the 

Sacramento River and its tributaries in California. Also included are river reaches and estuarine 

areas of the Sacramento-San Joaquin Delta, all waters from Chipps Island westward to Carquinez 

Bridge, including Honker Bay, Grizzly Bay, Suisun Bay, and Carquinez Strait, all waters of San 

Pablo Bay westward of the Carquinez Bridge, and all waters of San Francisco Bay (north of the 

San Francisco/Oakland Bay Bridge) from San Pablo Bay to the Golden Gate Bridge. Excluded 

are areas above specific dams or above longstanding, naturally impassable barriers. This ESU 

includes chinook salmon entering the Sacramento River from March to July and spawning from 

late August through early October, with a peak in September. Spring-run fish in the Sacramento 

River exhibit an ocean-type life history, emigrating as fry, subyearlings, and yearlings. 

Critical Habitat: 

A designation of critical habitat was proposed for this ESU in March 1998 and is expected to be 

finalized in March 1999. Proposed critical habitat includes all river reaches accessible to 

chinook salmon in the Sacramento River and its tributaries in California, all river reaches and 

estuarine areas of the Sacramento-San Joaquin Delta, all waters from Chipps Island westward to 

Carquinez Bridge, including Honker Bay, Grizzly Bay, Suisun Bay, and Carquinez Strait, all 

waters of San Pablo Bay westward of the Carquinez Bridge, and all waters of San Francisco Bay 

(north of the San Francisco/Oakland Bay Bridge) from San Pablo Bay to the Golden Gate Bridge. 

Excluded are areas above specific dams or above longstanding, naturally impassable barriers 

(i.e., natural waterfalls in existence for at least several hundred years). 

Major Impacts: 

Habitat problems are the most important source of ongoing risk to this ESU. Spring-run fish 

cannot access most of their historical spawning and rearing habitat in the Sacramento and San 

Joaquin River Basins (which is now above impassable dams), and current spawning is restricted 

to the mainstem and a few river tributaries in the Sacramento River. The remaining spawning 

habitat accessible to fish is severely degraded. Collectively, these habitat problems greatly 

reduce the resiliency of this ESU to respond to additional stresses in the future. The general 

degradation of conditions in the Sacramento River Basin (including elevated water temperatures, 

agricultural and municipal diversions and returns, restricted and regulated flows, entrainment of 

migrating fish into unscreened or poorly screened diversions, and the poor quality and quantity of 

remaining habitat) has severely impacted important juvenile rearing habitat and migration 

corridors. 

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Endangered Species Act Biennial Report to Congress 

There is also serious concern for threats to genetic integrity posed by hatchery programs in the
 

Central Valley. Most of the spring-run chinook salmon production in the Central Valley is of
 

hatchery origin, and naturally spawning populations may be interbreeding with both fall/late falland spring-run hatchery fish. In addition, hatchery strays are considered to be an increasing
 

problem due to the management practice of releasing a larger proportion of fish into the
 

Sacramento River delta and San Francisco Bay to avoid adverse river conditions.
 

Population Name: Central Valley, California, fall/late fall-run
 

Species Status: Proposed Threatened
 

Trend: Mixed; long term trends generally stable
 

Estimate: Average recent natural escapement above 200,000 fish
 

ESU Distribution/Description:
 

This ESU encompasses all naturally spawned populations of chinook salmon (and their progeny)
 

in the Sacramento and San Joaquin River Basins and their tributaries, east of Carquinez Strait,
 

California. Fall and late-fall chinook salmon enter the Sacramento and San Joaquin Rivers from
 

July through April and spawn from October through February. Both runs are ocean-type
 

chinook salmon, emigrating predominantly as fry and subyearlings and remaining off the
 

California coast during their ocean migration. 

Critical Habitat: 

A designation of critical habitat was proposed for this ESU in March 1998 and is expected to be 

finalized in March 1999. Proposed critical habitat includes all river reaches accessible to 

chinook salmon in the Sacramento and San Joaquin Rivers and their tributaries in California, all 

river reaches and estuarine areas of the Sacramento-San Joaquin Delta, all waters from Chipps 

Island westward to Carquinez Bridge, including Honker Bay, Grizzly Bay, Suisun Bay, and 

Carquinez Strait, all waters of San Pablo Bay westward of the Carquinez Bridge, and all waters 

of San Francisco Bay (north of the San Francisco/Oakland Bay Bridge) from San Pablo Bay to 

the Golden Gate Bridge. Excluded are areas upstream of the Merced River and areas above 

specific dams or above longstanding, naturally impassable barriers. 

Major Impacts 

A large proportion of the historic range of this ESU is severely degraded. Since most of fall/late 

fall-run spawning habitat is below dams, habitat blockage is not as severe for fall/late fall-run 

chinook as it is for winter- and spring-run chinook salmon in this region. However, there has 

been a severe degradation of the remaining habitat, especially due to agricultural and municipal 

water use activities in the Central Valley (which result in point and non-point pollution, elevated 

water temperatures, diminished flows, and smolt and adult entrainment into poorly screened or 

unscreened diversions). Additionally, stray rates are high because many hatchery fish are 

released into the Sacramento River delta and San Francisco Bay to avoid adverse river 

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Endangered Species Act Biennial Report to Congress 

conditions, resulting in a much larger proportion of hatchery chinook salmon present in the
 

natural spawning population.
 

A mitigating factor for the overall risk to the ESU is that a few of the Sacramento and San
 

Joaquin River Basin tributaries have shown recent, short-term increases in abundance. Total
 

population abundance in this ESU is relatively high, perhaps near historical levels, however, the
 

streams supporting natural runs considered to be the least influenced by hatchery fish have the
 

lowest abundance and the most consistently negative trends of all populations in the ESU. In
 

general, high hatchery production combined with infrequent monitoring of natural production
 

make assessing the sustainability of natural production problematic, resulting in substantial
 

uncertainty in assessing the status of this ESU.
 

Another concern facing chinook salmon in this ESU is the high ocean and freshwater harvest
 

rates in recent years, which may be higher than is sustainable by natural populations given the
 

productivity of the ESU under present habitat conditions. The mixed stock ocean salmon
 

fisheries off California are managed to achieve certain spawning escapement goals for two main
 

indicator stocks: Sacramento River fall chinook and Klamath River fall chinook. Since 1993, the
 

need to address Indian fishing rights in the Klamath River Basin has required significant
 

reductions in the ocean harvest rate on Klamath River fall chinook. The ocean harvest rates are
 

currently 71-79 percent and recent freshwater harvest is 25 percent.
 

Population Name: Southern Oregon & California Coastal
 

Species Status: Proposed Threatened
 

Trend: Mixed
 

Estimate: Average recent escapement about 132,000 in Oregon; few estimates for California
 

ESU Distribution/Description:
 

This ESU includes all naturally spawned coastal spring and fall chinook salmon spawning from
 

Cape Blanco (inclusive of the Elk River) to the southern extent of the current range for chinook
 

salmon at Point Bonita (the northern landmass marking the entrance to San Francisco Bay). 

Chinook salmon in this ESU exhibit an ocean-type life-history; ocean distribution is
 

predominantly off of the California and Oregon coasts.
 

Critical Habitat: 

A designation of critical habitat was proposed for this ESU in March 1998 and is expected to be 

finalized in March 1999. Proposed critical habitat includes all river reaches and estuarine areas 

accessible to chinook salmon in the drainages of San Francisco and San Pablo Bays, westward to 

the Golden Gate Bridge, and includes all estuarine and river reaches accessible to proposed 

chinook salmon on the California and southern Oregon coast to Cape Blanco (inclusive). 

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Endangered Species Act Biennial Report to Congress 

Excluded are the Klamath and Trinity Rivers upstream of their confluence. Also excluded are 

areas above specific dams or above longstanding, naturally impassable barriers. 

Major Impacts: 

Habitat loss and/or degradation is widespread throughout the range of the ESU. Habitat 

blockages and fragmentation, logging and agricultural activities, urbanization, and water 

withdrawals are reported as the most predominant problems for anadromous salmonids in 

California's coastal basins. Such problems also occur in Oregon streams within the ESU. The 

Rogue River Basin, in particular, has been affected by mining activities and unscreened irrigation 

diversions in addition to the problems resulting from logging and dam construction. 

Approximately one-third of spring chinook salmon spawning habitat in the Rogue River was 

inaccessible following the construction of Lost Creek Dam (River Kilometer 253) in 1977. 

Recent major flood events (February 1996 and January 1997) have probably affected habitat 

quality and survival of juveniles within this ESU. 

Artificial propagation programs in this ESU are less extensive than those in other ESUs. Current 

hatchery contribution to overall abundance is relatively low except for the Rogue River springrun. The hatchery-to-total run ratio of Rogue River spring chinook salmon, as measured at Gold 

Ray Dam (RKm 201), has exceeded 60% in some years. 

Population Name: Puget Sound 

Species Status: Proposed Threatened 

Trend: Mixed 

Estimate: Average current abundance 71,000 (spawning escapement) 

ESU Distribution/Description: 

This ESU encompasses all naturally spawned populations of chinook salmon from rivers and 

streams flowing into Puget Sound including the Straits of Juan De Fuca from the Elwha River 

eastward, including rivers and streams flowing into Hood Canal, South Sound, North Sound and 

the Strait of Georgia in Washington. Chinook salmon in this area all exhibit an ocean-type life 

history. 

Critical Habitat: 

A designation of critical habitat was proposed for this ESU in March 1998 and is expected to be 

finalized in March 1999. Proposed critical habitat includes all marine, estuarine and river 

reaches accessible to chinook salmon in Puget Sound. Puget Sound marine areas include South 

Sound, Hood Canal, and North Sound to the international boundary at the outer extent of the 

Strait of Georgia, Haro Strait and the Straits of Juan De Fuca to a straight line extending north 

from the west end of Freshwater Bay, inclusive. Excluded are areas above specific dams or 

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Endangered Species Act Biennial Report to Congress 

above longstanding, naturally impassable barriers (i.e., natural waterfalls in existence for at least 

several hundred years). 

Major Impacts: 

Habitat throughout the ESU has been blocked or degraded. In general, upper tributaries have 

been impacted by forest practices and lower tributaries and mainstem rivers have been impacted 

by agriculture and/or urbanization. Diking for flood control, draining and filling of freshwater 

and estuarine wetlands, and sedimentation due to forest practices and urban development are 

problems throughout the ESU. Blockages by dams, water diversions, and shifts in flow regime 

due to hydroelectric development and flood control projects are major habitat problems in several 

basins. 

Nearly 2 billion fish have been released into Puget Sound tributaries since the 1950s. The
 

preponderance of hatchery production throughout the ESU may mask trends in natural
 

populations and makes it difficult to determine whether they are self-sustaining. This difficulty
 

is compounded by the dearth of data pertaining to proportion of naturally-spawning fish that are
 

of hatchery origin.
 

Harvest impacts on Puget Sound chinook salmon stocks are quite high. Ocean exploitation rates
 

on natural stocks averaged 56-59%; overall harvest rates average 68-83% (1982-89). Total
 

exploitation rates on some stocks have exceeded 90%.
 

Population Name: Lower Columbia River
 

Species Status: Proposed Threatened
 

Trend: Mixed
 

Estimate: Recent natural spawning average about 40,000, with large hatchery component
 

ESU Distribution/Description:
 

This ESU encompasses all naturally spawned populations of chinook salmon (and their progeny)
 

from the Columbia River and its tributaries from its mouth at the Pacific Ocean upstream to a
 

transitional point between Washington and Oregon east of the Hood River and the White Salmon
 

River, and includes the Willamette River to Willamette Falls, Oregon. Populations in this ESU
 

are considered ocean type.
 

Critical Habitat: 

A designation of critical habitat was proposed for this ESU in March 1998 and is expected to be 

finalized in March 1999. Proposed critical habitat includes all river reaches accessible to 

chinook salmon in Columbia River tributaries between the Grays and White Salmon Rivers in 

Washington and the Willamette and Hood Rivers in Oregon, inclusive. Also included are river 

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Endangered Species Act Biennial Report to Congress 

reaches and estuarine areas in the Columbia River from a straight line connecting the west end of
 

the Clatsop jetty (south jetty, Oregon side) and the west end of the Peacock jetty (north jetty,
 

Washington side) upstream to The Dalles Dam. Excluded are areas above specific dams or
 

above longstanding, naturally impassable barriers (i.e., natural waterfalls in existence for at least
 

several hundred years).
 

Major Impacts:
 

All basins are affected (to varying degrees) by habitat degradation. Major habitat problems are
 

primarily related to blockages, forest practices, urbanization in the Portland and Vancouver areas,
 

and agriculture in floodplains and low-gradient tributaries.
 

Hatchery programs to enhance chinook salmon fisheries abundance in the lower Columbia River 

began in the 1870s, expanded rapidly, and have continued throughout this century. Although the 

majority of the stocks have come from within this ESU, over 200 million fish from outside the 

ESU have been released since 1930. The large numbers of hatchery fish in this ESU make it 

difficult to determine the proportion of naturally produced fish. 

Harvest rates on fall-run stocks are moderately high; recent average total harvest rate was 65 

percent (1982-89 brood years). The average ocean exploitation rate for this period was 46 

percent, while the freshwater harvest rate on the fall run has averaged 20 percent. Harvest rates 

are somewhat lower for spring run stocks. 

Population Name: Upper Willamette River 

Species Status: Proposed Threatened 

Trend: Declining 

Estimate: Recent total escapement averaged 26,000; however, naturally-spawning escapement 

may average 3,900 fish, of which only 1,300 are naturally produced. 

ESU Distribution/Description: 

This ESU includes naturally spawned spring-run populations of chinook salmon (and their 

progeny) in the Willamette River, and its tributaries, above Willamette Falls, Oregon. The ocean 

distribution is consistent with an ocean-type life history, and recoveries occur in considerable 

numbers in the Alaskan and British Columbian coastal fisheries. 

Critical Habitat: 

A designation of critical habitat was proposed for this ESU in March 1998 and is expected to be 

finalized in March 1999. Proposed critical habitat includes all river reaches accessible to 

chinook salmon in the Willamette River and its tributaries above Willamette Falls. Also 

included are river reaches and estuarine areas in the Columbia River from a straight line 

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Endangered Species Act Biennial Report to Congress 

connecting the west end of the Clatsop jetty (south jetty, Oregon side) and the west end of the 

Peacock jetty (north jetty, Washington side) upstream to and including the Willamette River in 

Oregon. Excluded are areas above specific dams or above longstanding, naturally impassable 

barriers (i.e., natural waterfalls in existence for at least several hundred years). 

Major Impacts: 

While the abundance of Willamette River spring chinook salmon has been relatively stable over 

the long term, and there is evidence of some natural production, it is apparent that at present 

production and harvest levels the natural population is not replacing itself. With natural 

production accounting for only 1/3 of the natural spawning escapement, it is questionable 

whether natural spawners would be capable of replacing themselves even in the absence of 

fisheries. While hatchery programs in the Willamette River Basin have maintained broodlines 

that are relatively free of genetic influences from outside the Willamette basin, they may have 

homogenized the population structure within the ESU. The introduction of fall-run chinook 

salmon into the basin and laddering of Willamette Falls have increased the potential for genetic 

introgression between wild spring-and hatchery fall-run chinook salmon, but there is no direct 

evidence of hybridization (other than an overlap in spawning times and spawning location) 

between these two runs. Prolonged artificial propagation of the majority of the production from 

this ESU may also have had deleterious effects on the ability of Willamette River spring chinook 

salmon to reproduce successfully in the wild. 

Habitat blockage and degradation are significant problems in this ESU. Available habitat has 

been reduced by construction of dams in the Santiam, McKenzie, and Middle Fork Willamette 

River Basins, and these dams have probably adversely affected remaining production via thermal 

effects. Agricultural development and urbanization are the main activities that have adversely 

affected habitat throughout the basin. 

Another concern for this ESU is that commercial and recreational harvests are high relative to the 

apparent productivity of natural populations. The average total harvest mortality rate was 

estimated to be 72 percent in 1982-89, with a corresponding ocean exploitation rate of 24 

percent. This estimate does not fully account for escapement, and ODFW is in the process of 

revising harvest rate estimates for this stock; revised estimates may average 57 percent total 

harvest rate, with 16 percent ocean and 48 percent freshwater components. The inriver 

recreational harvest rate (Willamette River sport catch/estimated run size) for the period from 

1991 through 1995 was 33 percent. 

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Endangered Species Act Biennial Report to Congress 

Population Name: Upper Columbia River, spring-run
 

Species Status: Proposed Endangered
 

Trend: Declining
 

Estimate: Recent average escapement fewer than 5,000; recent run sizes are lowest in 60 years
 

ESU Distribution/Description:
 

This ESU includes all naturally spawned populations of chinook (and their progeny) spawning
 

above Rock Island Dam--that is, those in the Wenatchee, Entiat, and Methow Rivers. These
 

upper Columbia River populations exhibit classical stream-type life-history strategies.
 

Critical Habitat: 

A designation of critical habitat was proposed for this ESU in March 1998 and is expected to be 

finalized in March 1999. Proposed critical habitat includes all river reaches accessible to 

chinook salmon in Columbia River tributaries upstream of the Rock Island Dam and downstream 

of Chief Joseph Dam in Washington, excluding the Okanogan River. Also included are river 

reaches and estuarine areas in the Columbia River from a straight line connecting the west end of 

the Clatsop jetty (south jetty, Oregon side) and the west end of the Peacock jetty (north jetty, 

Washington side) upstream to Chief Joseph Dam in Washington. Excluded are areas above 

specific dams or above longstanding, naturally impassable barriers (i.e., natural waterfalls in 

existence for at least several hundred years). 

Major Impacts: 

Access to a substantial portion of historical habitat was blocked by Chief Joseph and Grand 

Coulee Dams. There are local habitat problems related to irrigation diversions and hydroelectric 

development, as well as degraded riparian and instream habitat from urbanization and livestock 

grazing. Mainstem Columbia River hydroelectric development has resulted in a major disruption 

of migration corridors and affected flow regimes and estuarine habitat. Some populations in this 

ESU must migrate through nine mainstem dams. 

Artificial propagation efforts have had a significant impact on spring-run populations in this 

ESU, either through hatchery-based enhancement or the extensive trapping and transportation 

activities. It is probable that the majority of returning spring-run adults trapped at Rock Island 

Dam for use in hatchery-based enhancement were probably not native to the Wenatchee, Entiat, 

and Methow Rivers. Naturally spawning populations in tributaries upstream of hatchery release 

sites have apparently undergone limited introgression by hatchery stocks. Artificial propagation 

efforts have recently focused on supplementing naturally spawning populations in this ESU, 

although it should be emphasized that these naturally spawning populations were probably 

founded by the same homogenized stock. Furthermore, the potential for hatchery-derived nonnative stocks to genetically impact naturally spawning populations exists, especially given the 

recent low numbers of fish returning to rivers in this ESU. Risks associated with interactions 

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Endangered Species Act Biennial Report to Congress 

between wild and hatchery chinook salmon are a concern. 

Harvest rates are low for this ESU, with very low ocean and moderate instream harvest. Harvest 

rates have been declining recently. 

Population Name: Snake River fall 

Species Status: Threatened; redefined ESU proposed as threatened 

Trend: Declining 

Estimate: Total natural escapement averages about 6,500 

ESU Distribution/Description: 

This ESU is now believed to include additional fall-run populations; genetic analysis links fall 

chinook from the Deschutes River to the existing Snake River fall-run ESU. Populations in 

mainstem Columbia, John Day, Umatilla, and Walla Walla rivers are extinct, in addition to loss 

of populations that historically spawned above Hells Canyon Dam Complex. 

This ESU includes all natural population(s) of fall chinook in the mainstem Snake River and any 

of the following subbasins: Tucannon River, Grande Ronde River, Imnaha River, Salmon River, 

and Clearwater River. Snake River fall chinook salmon spawn in October and November in the 

mainstem Snake River from the upper limit of the Lower Granite Dam Reservoir to Hells 

Canyon Dam and the lower reaches of the Imnaha, Grande Ronde, Clearwater, and Tucannon 

Rivers or the lower parts of tributaries in October and November. This ESU includes ocen-type 

fish. 

Critical Habitat: 

Final critical habitat was designated for this ESU in December 1993. In March 1998, critical 

habitat was proposed to be revised to include all naturally spawned populations of chinook 

salmon (and their progeny) from the Columbia River and its tributaries upstream from a 

transitional point between Washington and Oregon east of the Hood River and the White Salmon 

River, to its confluence with the Snake River, and also includes the Snake River and its 

tributaries upstream to Hells Canyon Dam. These tributaries include the lower Grande Ronde, 

Imnaha, lower Salmon and lower Clearwater Rivers in parts of Oregon, Washington, and Idaho. 

Critical habitat is expected to be finalized in March 1999. 

Major Impacts: 

Almost all historical Snake River fall-run chinook salmon spawning habitat in the Snake River 

Basin was blocked by the Hells Canyon Dam complex; other habitat blockages have also 

occurred in Columbia River tributaries. Hydroelectric development on the mainstem Columbia 

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Endangered Species Act Biennial Report to Congress 

and Snake Rivers continues to affect juvenile and adult migration. Remaining habitat has been 

reduced by inundation in the mainstem Snake and Columbia Rivers, and the ESU's range has also 

been affected by agricultural water withdrawals, grazing, and vegetation management. 

The continued straying by non-native hatchery fish into natural production areas is an additional 

source of risk to the Snake River chinook salmon. 

Management changes have significantly reduced ocean harvest rates in the last six years. 

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Endangered Species Act Biennial Report to Congress 

Listed Species Status 

Chum Salmon: Oncorhynchus keta 

Along the U.S. West Coast, there are 4 distinct groups, or 

evolutionarily significant units (ESUs), of chum salmon. Two 

of these ESUs, Hood Canal summer-run and Columbia River, 

were proposed as threatened under the ESA in March 1998. Details about these proposed ESUs 

are summarized below by population. 

Species Biology 

Chum salmon belong to the family Salmonidae and are one of eight species of Pacific salmonids 

in the genus Oncorhynchus. Chum salmon are anadromous (adults migrate from a marine 

environment into the fresh water streams and rivers of their birth), semelparous (spawn only once 

and then die), and spawn primarily in fresh water. Chum salmon grow to be among the largest of 

Pacific salmon, second only to chinook salmon in adult size, with individuals reported up to 

108.9 cm in length and 20.8 kg in weight. Average size for the species is around 3.6 to 6.8 kg. 

The species is best known for the enormous canine-like fangs and striking body color (a calico 

pattern, with the anterior two-thirds of the flank marked by a bold, jagged, reddish line and the 

posterior third by a jagged black line) of spawning males. Females are less flamboyantly colored 

and lack the extreme dentition of the males. Chum salmon may historically have been the most 

abundant of all salmonids. 

Chum salmon spawn in the lowermost reaches of rivers and streams, typically within 100 km of 

the ocean. They migrate almost immediately after hatching to estuarine and ocean waters, in 

contrast to coho, chinook, sockeye and pink salmon, and steelhead and cutthroat trout, which 

migrate to sea after months or even years in fresh water. This means that survival and growth in 

juvenile chum salmon depend less on freshwater conditions (unlike stream-type salmonids which 

depend heavily on freshwater habitats) than on favorable estuarine and marine conditions. 

Another behavioral difference between chum salmon and most species that rear extensively in 

fresh water is that chum salmon form schools, presumably to reduce predation. Age at maturity 

appears to follow a latitudinal trend in which a greater number of older fish occur in the northern 

portion of the species’ range. Most chum salmon mature between 3 and 5 years of age, with 60 

to 90 percent of the fish maturing at 4 years of age. The species has only a single form (sea-run) 

and does not reside in fresh water. 

Distribution and Abundance 

The species has the widest natural geographic and spawning distribution of any Pacific salmonid, 

primarily because its range extends farther along the shores of the Arctic Ocean than that of the 

other salmonids. Historically, chum salmon were distributed throughout the coastal regions of 

western Canada and the United States, as far south as Monterey, California. Presently, major 

81
 
Endangered Species Act Biennial Report to Congress 

spawning populations are found only as far south as Tillamook Bay on the northern Oregon 

coast. 

Major Threats and Impacts 

See section entitled "Major Threats and Impacts to Pacific Salmonids" as well as more specific 

information under each population summary. 

ESU Status 

ESU Name Status Listing 

Date 

Population 

Trend 

Last 5 years 

Population 

Estimate 

Mean # 1994-1998 

Critical 

Habitat 

Lower Columbia 

River 

Proposed 

Threatened 

3/1999 Decreasing <1% historic 

levels 

Proposed 

Hood Canal 

Summer-run 

Proposed 

Threatened 

3/1999 Decreasing 4,00010 Proposed 

Population Name: Columbia River 

Status: Proposed Threatened 

Trend: Stable 

Estimate: Recent annual returns between 1,500 and 4,000 fish, compared to as many as 500,000 

before 1994 

ESU Distribution/Description: 

Historically, chum salmon were abundant in the lower reaches of the Columbia River and may 

have spawned as far upstream as the Walla Walla River (over 500 km inland); at least one ESU 

of chum salmon occurred in the Columbia River. Today only remnant chum salmon populations 

exist, all in the lower Columbia River. They are few in number, low in abundance, and of 

uncertain stocking history. The Columbia River ESU extends only to the mouth of the river. 

Critical Habitat: 

A designation of critical habitat was proposed for this ESU in March 1998 and is expected to be 

finalized in March 1999. Proposed critical habitat includes all naturally spawned populations of 

chum salmon (and their progeny) in the Columbia River and its tributaries in Washington and 

Oregon. 

10Mean for 1992-1996 

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Endangered Species Act Biennial Report to Congress 

Major Impacts: 

The Columbia River historically contained large runs of chum salmon that supported a 

substantial commercial fishery in the first half of this century. Current abundance is probably 

less than 1 percent of historical levels, and the ESU has undoubtedly lost some of its original 

genetic diversity. Many spill dams and other small hydropower facilities have been constructed 

in lower river areas, and Bonneville Dam presumably continues to impede recovery of upriver 

populations. Substantial habitat loss in the Columbia River estuary and associated areas 

presumably was an important factor in the decline and also represents a significant continuing 

risk for this ESU. 

Population Name: Hood Canal Summer-run
 

Status: Proposed Threatened
 

Trend: Mixed
 

Estimate: Recent annual returns of approximately 9,500 fish
 

ESU Distribution/Description:
 

This ESU includes summer-run chum salmon populations in Hood Canal in Puget Sound and in
 

Discovery and Sequim Bays on the Strait of Juan de Fuca. It may also include summer-run fish
 

in the Dungeness River, but the existence of that run is uncertain.
 

Critical Habitat: 

A designation of critical habitat was proposed for this ESU in March 1998 and is expected to be 

finalized in March 1999. Proposed critical habitat includes all naturally spawned populations of 

summer-run chum salmon (and their progeny) in Hood Canal and its tributaries as well as 

populations in Olympic Peninsula rivers between Hood Canal and Sequim Bay, Washington. 

Major Impacts: 

Hood Canal summer-run chum salmon have disappeared from several streams, and many other 

streams have experienced severe declines over the past twenty years. Historically, summer chum 

salmon have not been a primary fishery target in Hood Canal, as harvests have focused on other 

salmonids. However, summer chum salmon have a run timing that overlaps with those of 

chinook and coho salmon, and they have been incidentally harvested in fisheries directed at those 

species. Exploitation rates on summer-run chum salmon in Hood Canal have been greatly 

reduced since 1991 as a result of closures of the coho salmon fishery and of efforts to reduce the 

harvest of summer chum salmon. Threats to this population include degradation of spawning 

habitat, low water flows, and incidental harvest in salmon fisheries in the Strait of Juan de Fuca 

and coho salmon fisheries in Hood Canal. In addition, summer chum salon populations have 

shown a great deal of variability in productivity and run size in recent years, and this extreme 

variability can itself be a significant risk factor. 

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Endangered Species Act Biennial Report to Congress 

Listed Species Status 

Coho Salmon: Oncorhynchus kisutch 

Along the U.S. West Coast, there are 6 distinct 

groups, or evolutionarily significant units (ESUs), 

of chum salmon. Three of these ESUs, Central 

California, Southern Oregon/Northern California 

Coasts, and Oregon Coasts, were listed as 

threatened under the ESA in October 1996, May 

1997, and August 1998, respectively. Details 

about these proposed ESUs are summarized 

below by population. 

Species Biology 

Coho salmon belong to the family Salmonidae and are one of eight species of Pacific salmonids 

in the genus Oncorhynchus. Coho salmon are anadromous (adults migrate from a marine 

environment into the fresh water streams and rivers of their birth) and semelparous (spawn only 

once and then die). Coho spend approximately the first half of their life cycle rearing in streams 

and small freshwater tributaries. The remainder of the life cycle is spent foraging in estuarine 

and marine waters of the Pacific Ocean prior to returning to their stream of origin to spawn and 

die. Most adults are three-year old fish, however, some precocious males known as "jacks" 

return as two-year old spawners. A returning adult may measure more than two feet in length 

and weigh an average of eight pounds. 

Distribution and Abundance 

The species was historically distributed throughout the North Pacific Ocean from central 

California to Point Hope, Alaska, through the Aleutian Islands, and from the Anadyr River, 

Russia, south to Hokkaido, Japan. Historically, this species probably inhabited most coastal 

streams in Washington, Oregon, and central and northern California. Some populations, now 

considered extinct, are believed to have migrated hundreds of miles inland to spawn in tributaries 

of the upper Columbia river in Washington, and the Snake river in Idaho. 

Major Threats and Impacts 

See section entitled "Major Threats and Impacts to Pacific Salmonids" as well as more specific 

information under each population summary. 

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Endangered Species Act Biennial Report to Congress 

ESU Status 

ESU Name Status Listing 

Date 

Population 

Trend (Last 5 

years) 

Population 

Estimate 

Critical 

Habitat 

Oregon Coast Threatened 8/1998 declining 38,60011 

Southern 

Oregon/Northern 

California Coast 

Threatened 5/1997 unknown 8,50012 Proposed 

Central California 

Coast 

Threatened 10/1996 declining <6,000 Proposed 

Puget 

Sound/Straights of 

Georgia 

Candidate 7/1995 

Lower Columbia 

River/ SW 

Washington 

Candidate 7/1995 

Population Name: Central California Coast 

Status: Threatened 

Trend: Declining 

Estimate: <6,000 

ESU Distribution/Description: 

In the 1940s, estimated abundance of coho salmon in the Central California Coast ESU ranged 

from 50,000 to 125,000 natural spawning adults. Today, it is estimated that there are probably 

less than 6,000 naturally-reproducing coho salmon, and the vast majority of these fish are 

considered to be of non-native origin (either hatchery fish or from streams stocked with hatchery 

fish). The ESU consists of all coho salmon naturally reproduced in streams between Punta 

Gorda, Humboldt County, California and the San Lorenzo River, Santa Cruz County, California. 

Critical Habitat: 

A designation of critical habitat was proposed for this ESU in November 1997 and is expected to 

be finalized in November 1998. Proposed critical habitat encompasses accessible reaches of all 

rivers (including estuaries and tributaries) south of Punta Gorda in northern California up to and 

11Mean for 1990-1993; updated data not available 

12Data current through 1997 & 1998; Rogue and Trinity Dam counts 

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Endangered Species Act Biennial Report to Congress 

including California's San Lorenzo River. Also included are two rivers entering San Francisco
 

Bay: Mill Valley Creek and Corte Madera Creek.
 

Major Impacts:
 

The present depressed condition is the result of several human caused factors such as habitat
 

degradation, harvest, water diversions, and artificial propagation that exacerbate the adverse
 

effects of natural environmental variability from drought and poor ocean conditions.
 

Population Name: Oregon Coast 

Status: Threatened 

Trend: Declining 

Estimate: 39,000 

ESU Distribution/Description: 

This ESU includes coho salmon from Oregon coastal streams between Cape Blanco and the 

Columbia River 

Critical Habitat:
 

Critical habitat was not determinable at the time of listing; proposed critical habitat is expected to
 

be designated by August 1999.
 

Major Impacts:
 

The current abundance of coho salmon in this ESU is substantially less than it was historically. 

Population levels for Oregon coast coho have declined to approximately 5-10% of historic levels.
 

In addition, habitat degradation and inadequate regulatory mechanisms have posed continued
 

threats to this species' survival.
 

Population Name: Southern Oregon/Northern California Coast
 

Status: Threatened
 

Trend: Declining
 

Estimate: < 10,000 naturally-produced adults
 

ESU Distribution/Description:
 

This ESU is composed of coho salmon populations between Punta Gorda, California, and Cape
 

Blanco, Oregon. In the 1940's, estimated abundance in this ESU ranged from 150,000 to
 

400,000 naturally spawning fish. Today, coho populations in this ESU are very depressed,
 

currently numbering approximately 10,000 naturally produced adults.
 

Critical Habitat: 

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Endangered Species Act Biennial Report to Congress 

A designation of critical habitat was proposed for this ESU in November 1997 and is expected to 

be finalized in November 1998. Proposed critical habitat encompasses for the Southern 

Oregon/Northern California Coasts ESU encompasses accessible reaches of all rivers (including 

estuaries and tributaries) between the Mattole River in California and the Elk River in Oregon, 

inclusive. 

Major Impacts: 

Population levels of Southern Oregon/Northern California coast coho are substantially below 

historical levels. In the California portion of this ESU, about 36% of coho streams no longer 

have spawning runs. There has been widespread habitat degradation, and much of the remaining 

populations are hatchery-derived populations which may be genetically divergent from native 

strains. 

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Endangered Species Act Biennial Report to Congress 

Listed Species Status 

Coastal Cutthroat Trout: Oncorhynchus clarki clarki 

Species Biology 

Coastal cutthroat trout differ from all other 

trout by their profusion of small to mediumsize spots of irregular shape. In addition, they 

do not develop the brilliant colors associated 

with inland cutthroat trout (a separate 

subspecies). In the sea-run (anadromous) form 

of the coastal cutthroat trout, spots and colors are further obscured by the silvery skin deposit 

common to anadromous salmonids. Non-anadromous (resident) fish tend to be darker, with a 

"coppery or brassy" sheen. 

The life history of this subspecies is probably the most complex and flexible of any Pacific 

salmonid. Unlike other anadromous salmonids, sea-run forms of the coastal cutthroat trout do 

not overwinter in the ocean and only rarely make long extended migrations across large bodies of 

water. They migrate in the nearshore marine habitat and usually remain within 10 km of land. 

While most anadromous cutthroat trout enter seawater as 2- or 3- year olds, some may remain in 

fresh water up to 5 years before entering the sea. Other cutthroat trout may never outmigrate at 

all, but remain as residents of small headwater tributaries. Still other cutthroat trout may migrate 

only into rivers and lakes, even when they have access to the ocean. In the Umpqua River, 

anadromous, resident, and potamodromous (river-migrating) life-history forms have been 

reported. Details of the coastal cutthroat trout life history and ecology, including aspects 

particular to the various life forms, can be found in published reviews. 

Abundance and Distribution 

The Umpqua River cutthroat trout is a "distinct population segment" under the ESA (hereinafter 

referred to as an Evolutionarily Significant Unit or ESU (56 FR 58612; November 20, 1991)) of 

the coastal cutthroat trout (Oncorhynchus clarki clarki). The coastal cutthroat trout subspecies is 

native to western North America and is found in the coastal temperate rainforests from southeast 

Alaska to northern California. The Umpqua River cutthroat trout ESU inhabits a large coastal 

basin (drainage area over 12,200 square km) in the southwestern Oregon coast. Spawning sites 

are located in the North and South Umpqua Rivers and their tributaries, of which Smith River 

and Calapooya, Elk, and Scholfield Creeks are major tributaries. The estuary of the Umpqua 

River is one of the largest on the Oregon coast. 

Major Threats and Impacts 

See section entitled "Major Threats and Impacts to Pacific Salmonids" as well as more specific 

information under each population summary. 

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Endangered Species Act Biennial Report to Congress 

ESU Status 

ESU Name Status Listing 

Date 

Population 

Trend (Last 5 

years) 

Population 

Estimate 

Critical 

Habitat 

Umpqua River Endangered 8/1996 Decreasing unknown Designated 

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Endangered Species Act Biennial Report to Congress 

Listed Species Status 

Sockeye Salmon: Oncorhynchus nerka 

Along the U.S. West Coast, there are 7 

distinct groups, or evolutionarily significant 

units (ESUs), of sockeye salmon. One of 

these ESUs, Snake River, was listed as 

endangered in November 1991. In March 

1998, the Ozette Lake ESU was proposed 

as threatened and the Baker River ESU was 

designated as a candidate species. Details 

about the proposed and candidate ESUs are 

summarized below by population. 

Species Biology 

Sockeye salmon belong to the family 

Salmonidae and are one of seven species of Pacific salmonids in the genus Oncorhynchus. 

Sockeye salmon are anadromous, meaning they migrate from the ocean to spawn in fresh water. 

They are the third most abundant of the seven species of Pacific salmon, after pink and chum 

salmon. Unique in their appearance, the adult spawners typically turn bright red, with a green 

head, hence "red" salmon, as commonly called in Alaska. During the ocean and adult migratory 

phase sockeye often have a bluish back and silver sides, giving rise to another common name, 

"bluebacks." The name "sockeye" is thought to have been a corruption of the various Indian 

tribes’ word "sukkai." 

Sockeye salmon exhibit a wide variety of life history patterns that reflect varying dependency on 

the fresh water environment. With the exception of certain river-type and sea-type populations, 

the vast majority of sockeye salmon spawn in or near lakes, where the juveniles rear for 1 to 3 

years prior to migrating to sea. For this reason, the major distribution and abundance of large 

sockeye salmon stocks are closely related to the location of rivers that have accessible lakes in 

their watersheds for juvenile rearing. There are also O. nerka life forms that are nonanadromous, meaning that most members of the form spend their entire lives in freshwater. 

Non-anadromous O. nerka in the Pacific Northwest are known as kokanee. Occasionally, a 

proportion of the juveniles in an anadromous sockeye salmon population will remain in their 

rearing lake environment throughout life and will be observed on the spawning grounds together 

with their anadromous siblings. Taxonomically, the kokanee and sockeye salmon do not differ. 

Distribution and Abundance 

On the Pacific coast, sockeye salmon inhabit riverine, marine, and lake environments from the 

Columbia River and its tributaries north and west to the Kuskokwim River in western Alaska . 

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Endangered Species Act Biennial Report to Congress 

Major Threats and Impacts 

See section entitled "Major Threats and Impacts to Pacific Salmonids" as well as more specific 

information under each population summary. 

ESU Status 

ESU Name Status Listing 

Date 

Population 

Trend (Last 5 

years) 

Population 

Estimate 

Critical 

Habitat 

Snake River Endangered 11/1991 Decreasing 213 Designated 

Ozette Lake Proposed 

Threatened 

3/1998 Decreasing 70014 Proposed 

Baker River Candidate Stable 2,700 

Population Name: Ozette Lake 

Species Status: Proposed Threatened 

Trend: Declining 

Estimate: Recent average annual escapement was 700 fish 

ESU Distribution/Description: 

This ESU consists of sockeye salmon that return to Ozette Lake through the Ozette River and 

currently spawn primarily in lakeshore upwelling areas in Ozette Lake (particularly at Allen's 

Bay and Olsen's Beach). Minor spawning may occur below Ozette Lake in the Ozette River or in 

Coal Creek, a tributary of the Ozette River. Sockeye salmon do not presently spawn in tributary 

streams to Ozette Lake, although they may have spawned there historically. 

Kokanee are very numerous in Ozette Lake and spawn in inlet tributaries, whereas sockeye 

salmon spawn on lakeshore upwelling beaches. Sockeye have not been observed on the inlet 

spawning grounds of kokanee in Ozette Lake, although there are no physical barriers to prevent 

their entry into these tributaries. On the other hand, kokanee-sized O. nerka are observed 

together with sockeye salmon on the sockeye salmon spawning beaches at Allen's Bay and 

Olsen's Beach. 

Based on the very large genetic difference between Ozette Lake kokanee that spawn in tributaries 

and Ozette Lake sockeye salmon that spawn on shoreline beaches, Ozette Lake kokanee are not 

131992-1996 

14Mean for 1992-1996 

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Endangered Species Act Biennial Report to Congress 

included in this sockeye salmon ESU. However, if ``kokanee-sized'' O. nerka observed spawning
 

with sockeye salmon on sockeye salmon spawning beaches in Ozette Lake are identified as
 

resident sockeye salmon, they are to be considered as part of the Ozette Lake sockeye salmon
 

ESU.
 

Critical Habitat:
 

A designation of critical habitat was proposed for this ESU in March 1998 and is expected to be
 

finalized in March 1999. Proposed critical habitat includes all lake areas and river reaches
 

accessible to listed sockeye salon in Ozette Lake, located in Clallam county, Washington.
 

Major Impacts: 

The ESU is presently near the lower end of its historical abundance range. Current escapements 

averaging below 1,000 adults per year imply a moderate degree of risk from small-population 

genetic and demographic variability, with little room for further declines before abundances 

would be critically low. Other concerns include siltation of beach spawning habitat, very low 

abundance compared to harvest in the 1950s, and potential genetic effects of present hatchery 

production and past interbreeding with genetically dissimilar kokanee. 

Population Name: Baker River 

Species Status: Candidate 

Trend: Stable 

Estimate: Recent average annual escapement was about 2,700 adults 

ESU Distribution/Description: 

This ESU consists of sockeye salmon that return to the barrier dam and fish trap on the lower 

Baker River after migrating through the Skagit River. They are trucked to one of three artificial 

spawning beaches above either one or two dams on the Baker River and are held in these 

enclosures until spawning. 

Major Impacts: 

The recent average abundance is probably near the lower end of the historical abundance range 

for this ESU. Concerns are focused on high fluctuations in abundance, lack of natural spawning 

habitat, and the vulnerability of spawning beaches to water quality problems. Large fluctuations 

in abundance were a substantial concern. It is also likely that this stock would go extinct if 

present human intervention were halted and problems related to that intervention pose some risk 

to the population. This ESU bears close monitoring and its status should be reconsidered if 

abundance remains low. 

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Endangered Species Act Biennial Report to Congress 

Listed Species Status 

Steelhead Trout: 

Oncorhynchus mykiss 

Species Biology 

Steelhead has the greatest diversity of life history patterns of any Pacific salmonid species, 

including varying degrees of anadromy, differences in reproductive biology, and plasticity of life 

history between generations. Within the range of west coast steelhead, spawning migrations 

occur throughout the year, with seasonal peaks of activity. In any given river basin there may be 

one or more peaks of migration activity; since these runs are generally named for the season in 

which they occur, some rivers may have runs known as winter, spring, summer, or fall steelhead. 

For example, large rivers such as the Columbia, Rogue, and Klamath have migrating adult 

steelhead at all times of year. Through time, the names of seasonal runs have generally been 

simplified- in the Pacific Northwest, winter and summer steelhead runs are commonly identified. 

In northern California, some biologists have retained the terms spring and fall steelhead to name 

what others would call summer steelhead. 

North American steelhead commonly spend 2 years in the ocean before entering freshwater to 

spawn. Summer steelhead enter fresh water up to a year prior to spawning. Steelhead may 

spawn more than once. In some cases, the separation between anadromous steelhead and 

resident rainbow or redband trout is obscure (i.e., they look and behave similarly in freshwater). 

Distribution and Abundance 

West coast steelhead are presently distributed across about 15 degrees of latitude, from 

approximately 49°N at the U.S.-Canada border south to 34°N at the mouth of Malibu Creek, 

California. In some years steelhead may be found as far south as the Santa Margarita River in 

San Diego County. Climatic and geological features vary greatly across this area. 

Major Threats and Impacts 

Hydropower development; water withdrawal, conveyance, storage, and flood control; land use 

activities such as logging, road construction, urban development, grazing, mining, agriculture; 

loss of large woody debris, riparian habitat, and increased sedimentation; commercial, 

recreational, and tribal harvest; ocean conditions; and artificial propagation activities are all 

factors for the decline of steelhead throughout its range. See section entitled "Major Threats and 

Impacts to Pacific Salmonids" as well as more specific information under each population 

summary. 

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Endangered Species Act Biennial Report to Congress 

ESU Status 

ESU Name Status Listing 

Date 

Population 

Trend (Last 5 

years) 

Population 

Estimate 

Critical 

Habitat 

Snake River Threatened 8/1997 Decreasing 9,40015 

Upper Columbia 

River 

Endangered 8/1997 Decreasing 7,60016 

Southern 

California 

Endangered 8/1997 Decreasing 

Middle 

Columbia River 

Proposed 

Threatened 

3/1998 Decreasing 14,00017 

Lower Columbia 

River 

Threatened 3/1998 Decreasing 10,70018 

Upper 

Willamette 

River 

Proposed 

Threatened 

3/1998 Decreasing 5,40019 

Oregon Coast Candidate 3/1998 Increasing 7,800 

Klamath 

Mountains 

Province 

Candidate 3/1998 Decreasing 26,00020 

Northern 

California 

Candidate 3/1998 Decreasing 

South Central 

California Coast 

Threatened 8/1997 Decreasing 

Central Threatened 8/1997 Decreasing 

15Data current through 1998 

16Includes mixed hatchery & natural stocks 

17Includes mixed Deschutes stock (~1,300 fish) 

18Data current through 1997 

19Data current through 1997 

20Includes mixed stocks 

94
 
Endangered Species Act Biennial Report to Congress 

California 

Central Valley 

Threatened 3/1998 Decreasing 

Population Name: Snake River 

Species Status: Threatened 

Trend: Decreasing 

Estimate: 9,400 

ESU Distribution/Description 

This inland steelhead ESU occupies the Snake River Basin of southeast Washington, 

northeast Oregon and Idaho. While total runs size (hatchery plus natural) has increased since the 

mid-1970s, there has been a severe decline in natural run size. Downward trends and low parr 

densities indicate severe problems for “B-run” steelhead, the loss of which would substantially 

reduce life history diversity within the ESU. Genetic introgression from hatcheries is a major 

concern, with hatchery fish comprising as much as 86% of spawners. Degradation of freshwater 

habitat from grazing, irrigation diversions, and hydroelectric dams is also a major concern. 

The Snake River flows through terrain that is warmer and drier on an annual basis than the 

upper Columbia Basin or other drainages to the north. Geologically, the land forms are older and 

much more eroded than most other steelhead habitat. The eastern portion of the basin flows out 

of the granitic geological unit known as the Idaho Batholith. The western Snake River Basin 

drains sedimentary and volcanic soils of the Blue Mountains complex. Collectively, the 

environmental factors of the Snake River Basin result in a river that is warmer and more turbid, 

with higher pH and alkalinity, than is found elsewhere in the range of inland steelhead. 

Snake River Basin steelhead are summer steelhead (as are most inland steelhead) and 

comprise 2 groups, A-run and B-run, based on migration timing, ocean-age, and adult size. Snake 

River Basin steelhead enter fresh water from June to October and spawn the following spring 

from March to May. A-run steelhead are thought to be predominately l-ocean, while B-run 

steelhead are thought to be 2-ocean (IDFG, 1994). Snake River Basin steelhead usually smolt at 

age-2 or -3 years (Whitt, 1954; BPA, 1992; Hassemer, 1992). 

The steelhead population from Dworshak National Fish Hatchery (NFH) is the most divergent 

single population of inland steelhead based on genetic traits determined by protein 

electrophoresis. Additionally, steelhead returning to Dworshak NFH are considered to have a 

distinctive appearance and are the one steelhead population that is consistently referred to as Brun. NMFS considered the possibility that Dworshak NFH steelhead should be in their own ESU. 

However, little specific information was available regarding the characteristics of this 

population's native habitat in the North Fork Clearwater River, which is currently unavailable to 

anadromous fish due to blockage by Dworshak Dam. 

95
 
 

Endangered Species Act Biennial Report to Congress 

Population Name: Upper Columbia River 

Species Status: Endangered 

Trend: Decreasing 

Estimate: 7,600 

ESU Distribution/Description 

This inland steelhead ESU occupies the Columbia River Basin upstream from the Yakima 

River, WA, to the United States/Canada Border. Although total abundance of these populations 

have been relatively stable or even increasing, this is due to major hatchery supplementation 

programs. Hatchery fish make up 65% and 81% of spawning escapement in the Wenatchee and 

Methow/Okanogan Rivers, respectively. Ongoing impacts include habitat degradation from 

grazing, irrigation diversions, and hydroelectric dams; high harvest rates on steelhead smolts in 

rainbow trout fisheries; and genetic introgression from hatchery production. 

The geographic area occupied by this ESU forms part of the larger Columbia Basin Ecoregion 

(Omernik, 1987). The Wenatchee and Entiat Rivers are in the Northern Cascades Physiographic 

Province, and the Okanogan and Methow Rivers are in the Okanogan Highlands Physiographic 

Province. The geology of these provinces is somewhat similar and very complex, developed from 

marine invasions, volcanic deposits, and glaciation (Franklin & Dyrness, 1973). The river valleys 

in this region are deeply dissected and maintain low gradients except in extreme headwaters. The 

climate in this area includes extremes in temperatures and precipitation, with most precipitation 

falling in the mountains as snow. Streamflow in this area is provided by melting snowpack, 

groundwater, and runoff from alpine glaciers. Mullan et al. (1992) described this area as a harsh 

environment for fish and stated that ``it should not be confused with more studied, benign, 

coastal streams of the Pacific Northwest.''

 Life history characteristics for Upper Columbia River Basin steelhead are similar to those of 

other inland steelhead ESUs; however, some of the oldest smolt ages for steelhead, up to 7 years, 

are reported from this ESU. This may be associated with the cold stream temperatures (Mullan et 

al., 1992). Based on limited data available from adult fish, smolt age in this ESU is dominated by 

2-year-olds. Steelhead from the Wenatchee and Entiat Rivers return to fresh water after 1 year in 

salt water, whereas Methow River steelhead are primarily 2-ocean residents (Howell et al., 

1985). In 1939, the construction of Grand Coulee Dam on the Columbia River (RKm 

956) blocked anadromous fish access to over 1,800 km of river (Mullan et al., 1992). In an effort 

to preserve fish runs affected by Grand Coulee Dam, all anadromous fish migrating upstream 

were trapped at Rock Island Dam (RKm 729) from 1939 through 1943 and either released to 

spawn in tributaries between Rock Island and Grand Coulee Dams or spawned in hatcheries and 

the offspring released in that area (Peven, 1990; Mullan et al., 1992; Chapman et al., 1994). 

Through this process, stocks of all anadromous salmonids, including steelhead, which 

historically were native to several separate subbasins above Rock Island Dam, were randomly 

redistributed among tributaries in the Rock Island-Grand Coulee reach. Exactly how this has 

affected stock composition of steelhead is unknown. 

96
 
 

Endangered Species Act Biennial Report to Congress 

Population Name: Southern California 

Species Status: Endangered 

Trend: Declining 

Estimate: unknown 

ESU Distribution/Description 

This coastal steelhead ESU occupies rivers from (and including) the Santa Maria River to the 

southern extent of the species range which is presently considered to be Malibu Creek, in Los 

Angeles County (McEwan & Jackson, 1996). Steelhead have been extirpated from much of their 

historical range, primarily due to widespread degradation, destruction, and blockage of 

freshwater habitat from flood control, water development, land use, road-building, and other 

activitities. Water allocation and habitat destruction continues in many areas, and there may be 

harmful genetic impacts from widespread stocking of rainbow trout. 

Migration and life history patterns of southern California steelhead depend more strongly on 

rainfall and streamflow than is the case for steelhead populations farther north (Moore, 1980; 

Titus et al., in press). River entry ranges from early November through June, with peaks in 

January and February. Spawning primarily begins in January and continues through early June, 

with peak spawning in February and March. Average rainfall is substantially lower and more 

variable in this ESU than regions to the north, resulting in increased duration of sand berms 

across the mouths of streams and rivers and, in some cases, complete dewatering of the marginal 

habitats. 

Environmental conditions in marginal habitats may be extreme (e.g., elevated water 

temperatures, droughts, floods, and fires) and presumably impose selective pressures on 

steelhead populations. The species use of warm southern California streams and rivers with 

elevated temperatures by steelhead suggests that populations within this ESU are able to 

withstand higher temperatures than those to the north. The relatively warm and productive waters 

of the Ventura River resulted in more rapid growth of juvenile steelhead than occurrs in northerly 

populations. However, relatively little life history information exists for steelhead from this ESU. 

 Genetic data show large differences between steelhead populations within this ESU as well as 

between these and populations to the north. Steelhead populations between the Santa Ynez River 

and Malibu Creek show a predominance of a mtDNA type that is rare in populations to the north. 

Allozyme data indicate that two samples from Santa Barbara County are genetically among the 

most distinctive of any natural populations of coastal steelhead yet examined. Among the 

remaining questions regarding this ESU are the distribution and abundance of steelhead south of 

Malibu Creek. For example, in years of substantial rainfall there have been reports of steelhead in 

some coastal streams as far south as the Santa Margarita River, San Diego County (Hubbs, 1946; 

Barnhart, 1986; Higgins, 1991; McEwan & Jackson, 1996; Titus et al., in press). 

97
 
 

 

Endangered Species Act Biennial Report to Congress 

Population Name: Middle Columbia River 

Species Status: Proposed Threatened 

Trend: Decreasing 

Estimate: 14,000 

ESU Distribution/Description 

This inland steelhead ESU occupies the Columbia River Basin and tributaries from above 

(and excluding) the Wind River in Washington and the Hood River in Oregon, upstream to, and 

including, the Yakima River, in Washington. Steelhead of the Snake River Basin are excluded. 

Total steelhead abundance in the ESU appears to have been increasing recently, but the 

majority of natural stocks for which data is available have been declining, including those in the 

John Day River, which is the largest producer of wild, natural steelhead. There is pervasive 

opportunity for genetic introgression from hatchery stocks. Habitat degradation due to grazing 

and water diversions has been documented throughout the ESU. The status of populations in the 

Yakima River and winter steelhead are of particular concern. 

Franklin and Dyrness (1973) placed the Yakima River Basin in the Columbia Basin 

Physiographic Province, along with the Deschutes, John Day, Walla Walla, and lower Snake 

River Basins. Geology within this intermontane region is dominated by the Columbia River 

Basalt formation, and includes some of the driest areas of the Pacific Northwest, generally 

receiving less than 40 cm of rainfall annually (Jackson, 1993). Vegetation is of the shrub-steppe 

province, reflecting the dry climate and harsh temperature extremes. 

Genetic differences between inland and coastal steelhead are well established, although some 

uncertainty remains about the exact geographic boundaries of the two forms in the Columbia 

River. Electrophoretic and meristic data show consistent differences between steelhead from the 

middle Columbia and Snake Rivers. No recent genetic data exist for natural steelhead 

populations in the upper Columbia River, but recent WDFW data show that the Wells Hatchery 

stock from the upper Columbia River does not have a close genetic affinity to sampled 

populations from the middle Columbia River. All steelhead in the Columbia River Basin 

upstream from The Dalles Dam are summer-run, inland steelhead (Schreck et al., 1986; 

Reisenbichler et al., 1992; Chapman et al., 1994). Steelhead in Fifteen Mile Creek, OR, are 

genetically allied with inland O. mykiss, but are winter-run. Winter steelhead are also found in 

the Klickitat and White Salmon Rivers, WA. Life history information for this ESU indicates 

that most middle Columbia River steelhead smolt at 2 years and spend 1 to 2 years in salt water 

(i.e., 1-ocean and 2-ocean fish, respectively) prior to re-entering fresh water, where they may 

remain up to a year prior to spawning (Howell et al., 1985; Bonneville Power Association (BPA), 

1992). Within this ESU, the Klickitat River is unusual in that it produces both summer and 

winter steelhead, and the summer steelhead are dominated by 2-ocean steelhead (whereas most 

other rivers in this region produce about equal numbers of both 1-and 2-ocean steelhead). 

98
 
Endangered Species Act Biennial Report to Congress 

Population Name: Lower Columbia River 

Species Status: Threatened 

Trend: Decreasing 

Estimate: 10,700 

ESU Distribution/Description 

This coastal steelhead ESU occupies tributaries to the Columbia River between the Cowlitz 

and Wind Rivers in Washington and the Willamette and Hood Rivers in Oregon. Excluded are 

steelhead in the upper Willamette River Basin above Willamette Falls, and steelhead from the 

Little and Big White Salmon Rivers in Washington. Similar to Willapa Bay and Grays Harbor in 

southwest Washington, the lower Columbia River has extensive intertidal mud and sand flats and 

differs substantially from estuaries to the north and south. This similarity results from the shared 

geology of the area and the transportation of Columbia River sediments northward along the 

Washington coast. Rivers draining into the Columbia River have their headwaters in increasingly 

drier areas, moving from west to east. Columbia River tributaries that drain the Cascade 

Mountains have proportionally higher flows in late summer and early fall than rivers on the 

Oregon coast. 

This ESU is composed of winter steelhead and summer steelhead. The majority of 

populations for which data is available have been declining in the recent past, although some 

populations have shown increases. However, the strongest upward trends are for non-native 

stocks (Lower Willamette and Clackamas River summer steelhead) or stocks that are recovering 

from major habitat disruption and are still at low abundance (mainstem and North Fork Toutle 

River). There is pervasive opportunity for genetic introgression from hatchery stocks- there is 

widespread hatchery production, and several stocks have more than 50% hatchery fish in natural 

escapement. Concerns about hatchery influence are particularly great for summer steelhead and 

Oregon winter steelhead stocks, where there appears to be substantial overlap in spawning among 

hatchery and natural fish. 

Steelhead populations in this ESU are of the coastal genetic group (Schreck et al., 1986; 

Reisenbichler et al., 1992; Chapman et al., 1994), and a number of genetic studies have shown 

that they are part of a different ancestral lineage than inland steelhead from the Columbia River 

Basin. Genetic data also show steelhead from this ESU to be distinct from steelhead from the 

upper Willamette River and coastal streams in Oregon and Washington. WDFW data showed 

genetic affinity between the Kalama, Wind, and Washougal River steelhead. The data show 

differentiation between the Lower Columbia River ESU and the Southwest Washington and 

Middle Columbia River Basin ESUs. 

99
 
 

Endangered Species Act Biennial Report to Congress 

Population Name: Upper Willamette River 

Species Status: Proposed Threatened 

Trend: Decreasing 

Estimate: 5,4000 

ESU Distribution/Description 

This coastal steelhead ESU occupies the Willamette River and its tributaries, upstream from 

Willamette Falls near Portland, OR.. Native winter steelhead within this ESU have been 

declining since 1971, and have exhibited large fluctuations in abundance. The main production 

of native (late-run) winter steelhead is in the North Fork Santiam River, where estimates of 

hatchery proportion in natural spawning range from 14% to 54%. There is strong potential for 

genetic and ecological impacts from widespread production of hatchery steelhead within the 

range of this ESU, predominantly of non-native summer and early-run winter steelhead. 

The Willamette River Basin is zoogeographically complex. In addition to its connection to the 

Columbia River, the Willamette River historically has had connections with coastal basins 

through stream capture and headwater transfer events (Minckley et al., 1986). 

Steelhead from the upper Willamette River are genetically distinct from those in the lower 

river. Reproductive isolation from lower river populations may have been facilitated by 

Willamette Falls, which is known to be a migration barrier to some anadromous salmonids. For 

example, winter steelhead and spring chinook salmon (O. tshawytscha) occurred historically 

above the falls, but summer steelhead, fall chinook salmon, and coho salmon did not (Pacific Gas 

and Electric (PGE), 1994). 

The native steelhead of this basin are late-migrating winter steelhead, entering fresh water 

primarily in March and April (Howell et al., 1985), whereas most other populations of west coast 

winter steelhead enter fresh water beginning in November or December. As early as 1885, fish 

ladders were constructed at Willamette Falls to aid the passage of anadromous fish. The ladders 

have been modified and rebuilt, most recently in 1971, as technology has improved (Bennett, 

1987; PGE, 1994). These fishways facilitated successful introduction of Skamania stock summer 

steelhead and early-migrating Big Creek stock winter steelhead to the upper basin. Another effort 

to expand the steelhead production in the upper Willamette River was the stocking of native 

steelhead in tributaries not historically used by that species. Native steelhead primarily used 

tributaries on the east side of the basin, with cutthroat trout predominating in streams draining the 

west side of the basin. Nonanadromous O. mykiss are known to occupy the Upper Willamette 

River Basin; however, most of these nonanadromous populations occur above natural and 

manmade barriers (Kostow, 1995). 

Historically, spawning by Upper Willamette River steelhead was concentrated in the North 

and Middle Santiam River Basins (Fulton, 1970). These areas are now largely blocked to fish 

passage by dams, and steelhead spawning is now distributed throughout more of the Upper 

Willamette River Basin than in the past (Fulton, 1970). Due to introductions of non-native 

steelhead stocks and transplantation of native stocks within the basin, it is difficult to formulate a 

clear picture of the present distribution of native Upper Willamette River steelhead, and their 

relationship to nonanadromous and possibly residualized O. mykiss within the basin. 

100
 
 

 

Endangered Species Act Biennial Report to Congress 

Population Name: Oregon Coast 

Species Status: Candidate 

Trend: Increasing 

Estimate: 7,800 

ESU Distribution/Description 

This coastal steelhead ESU occupies river basins on the Oregon coast north of Cape Blanco, 

excluding rivers and streams that are tributaries of the Columbia River. Most steelhead 

populations in this ESU have been declining in the recent past, with increasing trends restricted 

to the southernmost portion of the ESU, south of Siuslaw Bay. There is strong potential for 

adverse genetic and ecological impacts from extensive and widespread hatchery production, 

largely based on out-of-basin stocks. Approximately half the streams are estimated to have more 

than 50% hatchery fish in natural spawning escapements. 

Most rivers in this area drain the Coast Range Mountains, have a single peak in flow in 

December or January, and have relatively low flow during summer and early fall. The coastal 

region receives fairly high precipitation levels, and the vegetation is dominated by Sitka spruce 

and western hemlock. Upwelling off the Oregon coast is much more variable and generally 

weaker than areas south of Cape Blanco. While marine conditions off the Oregon and 

Washington coasts are similar, the Columbia River has greater influence north of its mouth, and 

the continental shelf becomes broader off the Washington coast. 

Recent genetic data from steelhead in this ESU are limited, but they show a level of 

differentiation from populations from Washington, the Columbia River Basin, and coastal areas 

south of Cape Blanco. Ocean migration patterns also suggest a distinction between steelhead 

populations north and south of Cape Blanco. Steelhead (as well as chinook and coho salmon) 

from streams south of Cape Blanco tend to be south-migrating rather than north-migrating 

(Everest, 1973; Nicholas & Hankin, 1988; Pearcy et al., 1990; Pearcy, 1992). The Oregon 

Coast ESU primarily contains winter steelhead; there are only two native stocks of summer 

steelhead. Summer steelhead occur only in the Siletz River, above a waterfall, and in the North 

Umpqua River, where migration distance may prevent full utilization of available habitat by 

winter steelhead. Alsea River winter steelhead have been widely used for steelhead broodstock in 

coastal rivers as compared with other areas. Populations of nonanadromous O. mykiss are 

relatively uncommon on the Oregon coast, occurring primarily above migration barriers and in 

the Umpqua River Basin (Kostow, 1995). Little information is available regarding migration 

and spawn timing of natural steelhead populations within this ESU. Age structure appears to be 

similar to other west coast steelhead, dominated by 4-year-old spawners. Iteroparity (multiple 

spawning runs) is more common among Oregon coast steelhead than populations to the north. 

101
 
Endangered Species Act Biennial Report to Congress 

Population Name: Klamath Mountains Province 

Species Status: Candidate 

Trend: Decreasing 

Estimate: 26,000 

ESU Distribution/Description 

This coastal steelhead ESU occupies river basins from the Elk River in Oregon to the Klamath 

and Trinity Rivers in California, inclusive. Although historical abundance trends are not clearly 

known, there has been substantial replacement of naturally-produced fish with hatchery fish. 

While absolute abundance remains fairly high, since about 1970 trends in abundance have been 

downward in most steelhead populations for which data is available, and some populations are 

considered to be at risk of extinction. Declines in summer steelhead populations are of particular 

concern. After accounting for the contribution of hatchery fish, NMFS is unable to identify any 

remaining populations that are naturally self-sustaining. 

Geologically, this region includes the Klamath Mountains Province, which is not as erosive as 

the Franciscan formation terrains south of the Klamath River Basin. Dominant vegetation along 

the coast is redwood forest, while some interior basins are much drier than surrounding areas and 

are characterized by many endemic species. Elevated stream temperatures are a factor affecting 

steelhead and other species in some of the larger river basins. With the exception of major river 

basins such as the Rogue and Klamath, most rivers in this region have a short duration of peak 

flows. Strong and consistent coastal upwelling begins at about Cape Blanco and continues south 

into central California, resulting in a relatively productive nearshore marine environment. 

Protein electrophoretic analyses of coastal steelhead have indicated genetic discontinuities 

between the steelhead of this region and those to the north and south (Hatch, 1990; Busby et al., 

1993, 1994). Chromosomal studies have also identified a distinctive karyotype that has been 

reported only from populations within this ESU. Steelhead within this ESU include both winter 

and summer steelhead as well as the unusual ``half-pounder'' life history (characterized by 

immature steelhead that return to fresh water after only 2 to 4 months in salt water, overwinter in 

rivers without spawning, then return to salt water the following spring).

 Among the remaining questions regarding this ESU is the relationship between O. mykiss 

below and above Klamath Falls, OR. Behnke (1992) has proposed that the two groups are in 

different subspecies, and that the upper group, a redband trout (O. m. newberrii), exhibited 

anadromy until blocked by the Copco dams in the early 1900's. However, Moyle (1976) stated 

that Klamath Falls was the upstream barrier to anadromous fish prior to construction of the dams. 

102
 
Endangered Species Act Biennial Report to Congress 

Population Name: Northern California 

Species Status: Candidate 

Trend: Declining 

Estimate: unknown 

ESU Distribution/Description 

This coastal steelhead ESU occupies river basins from Redwood Creek in Humboldt County, 

CA south to the Gualala River, inclusive. Current population levels are very low compared to 

historic counts (1930s dam counts), and recent trends are downward where data is available. 

There is particular concern regarding sedimentation and channel restructuring due to floods, 

apparently due at least in part from poor land management practices. The abundance of 

Sacramento pikeminnow (Sacremento squawfish) (Ptychocheilus grandis) as a predator in the 

Eel River is also a concern. Hatcheries, such as the Mad River hatchery, have the potential cause 

genetic introgression and other adverse impacts to natural spawning stocks. 

Dominant vegetation along the coast is redwood forest, while some interior basins are much 

drier than surrounding areas and are characterized by many endemic species. This area includes 

the extreme southern end of the contiguous portion of the Coast Range Ecoregion (Omernick, 

1987). Elevated stream temperatures are a factor in some of the larger river basins (greater than 

20 deg.C), but not to the extent that they are in river basins farther south. Precipitation is 

generally higher in this geographic area than in regions to the south, averaging 100-200 cm of 

rainfall annually (Donley et al., 1979). With the exception of major river basins such as the Eel, 

most rivers in this region have peak flows of short duration. Strong and consistent coastal 

upwelling begins at about Cape Blanco and continues south into central California, resulting in a 

relatively productive nearshore marine environment. 

There are life history similarities between steelhead of the Northern California ESU and the 

Klamath Mountains Province ESU. The latter ESU includes both winter and summer steelhead, 

(including what is presently considered to be the southernmost population of summer steelhead), 

in the Middle Fork Eel River. Half-pounder juveniles also occur in this geographic area, 

specifically in the Mad and Eel Rivers. Snyder (1925) first described the half-pounder from the 

Eel River; however, Cramer et al. (1995) suggested that adults with the half-pounder juvenile life 

history may not spawn south of the Klamath River Basin. As with the Rogue and Klamath 

Rivers, some of the larger rivers in this area have migrating steelhead year-round, and seasonal 

runs have been named. River entry ranges from August through June and spawning from 

December through April, with peak spawning in January in the larger basins and late February 

and March in the smaller coastal basins. 

103
 
Endangered Species Act Biennial Report to Congress 

Population Name: South Central California Coast 

Species Status: Threatened 

Trend: Declining 

Estimate: unknown 

ESU Distribution/Description 

This coastal steelhead ESU occupies rivers from the Pajaro River, located in Santa Cruz 

County, CA, to (but not including) the Santa Maria River. Total abundance of steelhead in this 

ESU is extremely low, and most stocks for which data is available show recent downward trends. 

Habitat degradation from water development, poor land use practices, and floods are of particular 

concern. There is also concern about genetic effects of widespread stocking of rainbow trout. 

Most rivers in this ESU drain the Santa Lucia Range, the southernmost of the California Coast 

Ranges. The climate is drier and warmer than in the north, which is reflected in the vegetational 

change from coniferous forest to chaparral and coastal scrub. Another biological transition at the 

north of this area is the southern limit of the distribution of coho salmon (O. kisutch). The 

mouths of many of the rivers and streams in this area are seasonally closed by sand berms that 

form during periods of low flow in the summer. The southern boundary of this ESU is near Point 

Conception, a well-known transition area for the distribution and abundance of marine flora and 

fauna. 

Mitochondrial DNA data provide evidence for a genetic transition in the vicinity of Monterey 

Bay. Both mtDNA and allozyme data show large genetic differences between populations in this 

area, but do not provide a clear picture of population structure. Only winter steelhead are found 

in this ESU. River entry ranges from late November through March, with spawning from January 

through April. Little other life history information exists for steelhead in this ESU. The 

relationship between anadromous and nonanadromous O. mykiss, including possibly residualized 

fish upstream from dams, is unclear, but likely to be important. 

Population Name: Central California Coast 

Species Status: Threatened 

Trend: Declining 

Estimate: unknown 

ESU Distribution/Description 

This coastal steelhead ESU occupies river basins from the Russian River in Sonoma County 

to Soquel Creek, Santa Cruz County (inclusive), and the drainages of San Francisco and San 

Pablo Bays; excluded is the Sacramento-San Joaquin River Basin of the Central Valley of 

California. This area is characterized by very erosive soils in the coast range mountains; redwood 

forest is the dominant coastal vegetation for these drainages. Precipitation is lower here than in 

areas to the north, and elevated stream temperatures (greater than 20 deg.C) are common in the 

summer. Coastal upwelling in this region is strong and consistent, resulting in a relatively 

productive nearshore marine environment. 

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Endangered Species Act Biennial Report to Congress 

Analysis of mtDNA data suggests that genetic transitions occur north of the Russian River 

and north of Monterey, California. Allozyme data show large genetic differences between 

steelhead populations from the Eel and Mad Rivers and those to the south. Only winter steelhead 

are found in this ESU and those to the south. River entry ranges from October in the larger basins 

to late November in the smaller coastal basins, and continues through June. Steelhead spawning 

begins in November in the larger basins, December in the smaller coastal basins, and can 

continue through April, with peak spawning generally in February and March. Little other life 

history information exists for steelhead in this ESU. 

Historical abundance estimates are available for some stocks within this ESU, but no overall 

estimates are available prior to 1961, when Hallock et al. (1961) estimated a total run size of 

40,000 steelhead in the Sacramento River, including San Francisco Bay. In the mid-1960s, 

CDFG estimated steelhead spawning populations for the rivers in this ESU, totaling almost 

27,000 fish. We have limited data on recent abundance for this ESU, but its present total run size 

(based on dam counts, hatchery returns, and past spawning surveys) is probably less than 10,000 

fish. Both natural and hatchery runs have declined since the 1960s. 

Population Name: California Central Valley 

Species Status: Threatened 

Trend: Declining 

Estimate: unknown 

ESU Distribution/Description 

Central Valley steelhead are in danger of extinction. They have already been extirpated from 

most of their historical range. Habitat concerns are principally the widespread degradation, 

destruction, and blockage of freshwater habitat, and the potential impacts of continuing habitat 

destruction and water diversion. There is also the potential for genetic impacts from hatchery 

steelhead production within the area of the ESU. 

In the mid-1960s, CDFG (1965) estimated 94,000 steelhead spawning in many rivers of this 

ESU, but adequate adult escapement information is not available to compute trends for any 

individual stocks. However, general trends can be inferred from the comparison of 1960s and 

1990s abundance estimates, and these indicate substantial rates of decline in the two largest 

steelhead stocks (Russian and San Lorenzo Rivers). These data indicate that recent total 

abundance in these two rivers is probably less than 15% of their abundance 30 years ago. In 

addition, McEwan and Jackson (1996) noted that steelhead in most streams tributary to San 

Francisco and San Pablo Bays have been extirpated, although small "fair to good" runs of 

steelhead reportedly occur in coastal Marin County tributaries. 

This coastal steelhead ESU occupies the Sacramento and San Joaquin Rivers and their 

tributaries. The Sacramento and San Joaquin Rivers offer the only migration route to the 

drainages of the Sierra Nevada and southern Cascade mountain ranges for anadromous fish. The 

distance from the Pacific Ocean to spawning streams can exceed 300 km, providing unique 

potential for reproductive isolation among steelhead. The Central Valley is much drier than the 

coastal regions to the west, receiving on average only 10-50 cm of rainfall annually. Steelhead 

105
 
Endangered Species Act Biennial Report to Congress 

within this ESU have the longest freshwater migration of any population of winter steelhead. 

There is essentially one continuous run of steelhead in the upper Sacramento River. River entry 

ranges from July through May, with peaks in September and February. Spawning begins in late 

December and can extend into April. 

Steelhead ranged throughout the tributaries and headwaters of the Sacramento and San 

Joaquin Rivers prior to dam construction, water development, and watershed perturbations of the 

19th and 20th centuries. Present steelhead distribution in the central valley drainages has been 

greatly reduced (McEwan & Jackson, 1996), particularly in the San Joaquin basin. 

Among the remaining questions regarding this ESU are the current presence, distribution, and 

abundance of steelhead in the San Joaquin River and its main tributaries (Stanislaus, Tuolumne, 

and Merced Rivers), and whether these steelhead stocks historically represented a separate ESU 

from those in the Sacramento River Basin. Also, the relationship between anadromous and 

nonanadromous O. mykiss, including possibly residualized fish upstream from dams, is unclear. 

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Major Threats and Impacts to Pacific Salmonids 

Salmonid species on the west coast of the United States have experienced dramatic declines in 

abundance during the past several decades as a result of human-induced and natural factors. 

There is no single factor solely responsible for this decline. Given the complexity of the salmon 

species life history and the ecosystem in which they reside, it is difficult to precisely quantify the 

relative contribution of any one factor to the decline of a given species. Rather, given the 

available data, it is only possible to highlight factors which have significantly affected the status 

of a particular species. 

Water storage, withdrawal, conveyance, and diversions for agriculture, flood control, domestic, 

and hydropower purposes have greatly reduced or eliminated historically accessible habitat 

and/or resulted in direct entrainment mortality of juvenile salmonids. Modification of natural 

flow regimes have resulted in increased water temperatures, changes in fish community 

structures, depleted flows necessary for migration, spawning, rearing, 

flushing of sediments from spawning gravels, gravel recruitment and 

transport of large woody debris. Physical features of dams, such as 

turbines and sluiceways, have resulted in increased mortality of both 

adults and juvenile salmonids. Attempts to mitigate adverse impacts of 

these structures have to date met with limited success. 

Natural resource use and extraction leading to habitat modification can 

have significant direct and indirect impacts to salmon populations. Land 

use activities associated with logging, road construction, urban 

development, 

mining, agriculture, and recreation have 

significantly altered fish habitat quantity and 

quality. Associated impacts of these 

activities include: alteration of streambanks 

and channel morphology; alteration of 

ambient stream water temperatures; 

degradation of water quality; reduction in 

available food supply; elimination of 

spawning and rearing habitat; fragmentation 

of available habitats; elimination of 

downstream recruitment of spawning gravels 

and large woody debris; removal of riparian 

vegetation resulting in increased stream bank 

erosion; and increased sedimentation input 

into spawning and rearing areas resulting in the loss of channel complexity, pool habitat, suitable 

gravel substrate, and large woody debris. Studies indicate that in most western states, about 80 to 

90 percent of the historic riparian habitat has been eliminated. Further, it has been estimated that 

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during the last 200 years, the lower 48 United States have lost approximately 53 percent of all 

wetlands. Washington and Oregon’s wetlands have been estimated to have been diminished by 

one third, while it is estimated that California has experienced a 91 percent loss of its wetland 

habitat. 

The degree of spatial and temporal connectivity between and with watersheds is an important 

consideration for maintaining aquatic riparian ecosystem functions. Loss of this connectivity and 

complexity, such as the loss of deep pool habitats, has contributed to the decline of salmon. In 

Washington, the number of large, deep pools in National Forest streams has decreased by as 

much as 58 percent due to sedimentation and loss of pool-forming structures such as boulders 

and large wood. Similarly, in Oregon, the abundance of large, deep pools on private coastal 

lands has decreased by as much as 80 percent. 

Salmon have been, and continue to be, an important target species for recreational fisheries 

throughout their range. During periods of decreased habitat availability, the impacts of 

recreational fishing on native anadromous stocks may be 

heightened. Commercial fishing on unlisted, healthier stocks has 

caused adverse impacts to weaker stocks of salmon, and illegal 

high seas driftnet fishing in past years may have also been partially 

responsible for declines in salmon abundance. However, such 

fisheries cannot account for the total declines in salmon abundance 

in North America. 

Introduction of non-native species and modification of habitat have 

resulted in increased predator populations and salmonid predation 

in numerous river and estuarine systems. Piscivorous birds such as 

terns and cormorants, and pinnipeds such as sea lions and harbor 

seals are examples of potential salmon predators. Marine 

predation is also of concern in areas of dwindling salmon run-size. In general, predation rates on 

salmon are considered by most investigators to be an insignificant contribution to the large 

declines observed in west coast populations. However, predation may significantly influence 

salmonid abundance in some local populations when other prey are absent and physical 

conditions, such as narrow river mouths or human-made barriers such as fishing locks, lead to 

the concentration of adult and juvenile salmonids. 

Natural environmental conditions have served to exacerbate the problems associated with 

degraded and altered riverine and estuarine habitats. Recent floods and persistent drought 

conditions have reduced already limited spawning, rearing, and migration habitat. Furthermore, 

climatic shifts over a decadal time scale appear to have resulted in decreased ocean productivity 

which may exacerbate degraded freshwater habitat conditions to some degree. Environmental 

conditions such as these have gone largely unnoticed until recently, when salmonid populations 

have reached critical low levels. 

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In an attempt to mitigate for lost habitat and reduced fisheries, extensive hatchery programs have 

been implemented throughout the range of salmon on the west coast. While some of these 

programs have been successful in providing fishing opportunities, the impacts of these programs 

on wilds stocks are not well understood. Competition, genetic introgression, and disease 

transmission resulting from hatchery introductions may significantly impact the production and 

survival of wild salmon. Commercial and recreational fisheries targeting stronger stocks 

supported by hatchery production may inadvertently result in adverse impacts to weaker, wild 

stocks. Furthermore, collection and utilization of wild fish for broodstock purposes may result in 

additional negative impacts to small or dwindling natural populations. 

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Listed Species Status 

Gulf Sturgeon: Acipenser oxyrynchus 

Listing Date: 09/30/91 

The National Marine Fisheries Service 

(NMFS) and US Fish and Wildlife Service 

(FWS) listed the Gulf sturgeon as a 

threatened species on September 30, 1991. 

NMFS and FWS share jurisdiction for this 

species under the Endangered Species Act. 

Species Biology 

The Gulf sturgeon, also known as the Gulf of Mexico sturgeon, is a subspecies of the Atlantic 

sturgeon. It is a large fish with an extended snout, vertical mouth, chin barbels, and with the 

upper lobe of the tail longer than the lower. Adults are 180 to 240 cm (71-95 inches) in length, 

with adult females larger than adult males. The skin is scaleless, brown dorsally and pale 

ventrally and imbedded with 5 rows of bony plates. 

Adult fish are bottom feeders, eating primarily invertebrates, including brachiopods, insect 

larvae, mollusks, worms and crustaceans. Gulf sturgeon are anadromous, with reproduction 

occurring in fresh water. Most adult feeding takes place in the Gulf of Mexico and its estuaries. 

The fish return to breed in the river system in which they hatched. Spawning is believed to occur 

in areas of deep water with clean (rock and rubble) bottoms. The eggs are sticky and adhere in 

clumps to snags, outcroppings, or other clean surfaces. Sexual maturity is reached between the 

ages of 8 and 12 years for females and 7 and 10 years for males. 

Distribution and Abundance 

Historically, the Gulf sturgeon occurred from the Mississippi River to Charlotte Harbor, Florida. 

It still occurs, at least occasionally, throughout this range, but in greatly reduced numbers. The 

fish is essentially confined to the Gulf of Mexico. River systems where the Gulf sturgeon are 

known to be viable today include the Mississippi, Pearl, Escambia, Yellow, Choctawhatchee, 

Appalachicola and Suwannee rivers. 

Major Threats and Impacts 

As with sturgeon worldwide, dams have been a significant factor in the decline of the Gulf 

sturgeon. Three major rivers (the Pearl in Mississippi, the Alabama in Alabama, and the 

Appalachicola in Florida) within the range of the Gulf sturgeon have been dammed, preventing 

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use of upstream areas for spawning. The Gulf sturgeon are unable to pass through dam and lock 

systems. 

In addition to the structures preventing Gulf sturgeon from reaching spawning areas, dredging, 

desnagging, and spoil deposition carried out in connection with channel improvement and 

maintenance represent a threat to the Gulf sturgeon. Although exact spawning areas are not 

known for all river systems the Gulf sturgeon inhabit, indications are that submerged rock ledges 

and clean rock surfaces are important for spawning. Modification of such features, especially in 

rivers in which upstream migration is limited by dams, could further jeopardize the reduced 

stocks of the Gulf sturgeon. 

Conservation and Recovery Efforts 

A Recovery and Management Plan for Gulf sturgeon was completed in September 1995. Genetic 

analyses of Gulf sturgeon indicate the population is divided into five genetically distinct stocks, 

each occupying a unique watershed or geographical unit. Also, Gulf sturgeon spawning and 

resting habitat have been documented and characterized in three river systems. Population 

surveys and freshwater and marine movement and migratory behavior have been studied in six 

watersheds. In addition, Gulf sturgeon outreach activities have contributed much toward public 

education. 

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Listed Species Status 

Shortnose Sturgeon: Acipenser brevirostrum 

Listing Date: 03/11/67 

The shortnose sturgeon was listed as 

endangered throughout its range on 

March 11, 1967. It is an anadromous 

fish that spawns in the coastal rivers 

along the east coast of North 

America from the St. John River in 

Canada to the St. Johns River in Florida. It prefers the nearshore marine, estuarine and riverine 

habitat of large river systems. Shortnose sturgeon, unlike other anadromous species in the region 

such as shad or salmon, do not appear to make long distance offshore migrations. 

No estimate of the historical population size of shortnose sturgeon is available. While the 

shortnose sturgeon was rarely the target of a commercial fishery, it often was taken incidentally 

in the commercial fishery for Atlantic sturgeon. In the 1950s, sturgeon fisheries declined on the 

east coast which resulted in a lack of records of shortnose sturgeon. This led the Fish and 

Wildlife Service (FWS) to conclude that the fish had been eliminated from the rivers in its 

historic range (except the Hudson River) and was in danger of extinction. FWS believed the 

population level of the shortnose sturgeon had declined because of pollution and overfishing, 

both directly and incidentally in shad gillnets. 

Species Biology 

The sturgeon family is among the most primitive of the bony fishes. The shortnose sturgeon 

shares the same general external morphology of all sturgeon. Its elongated fusiform body is 

moderately depressed, and its protractable subterminal mouth with barbels is well suited for 

bottom feeding and a generally benthic existence. The body surface contains five rows of bony 

plates or scutes. Shortnose sturgeon are large, long-lived fish that inhabit a great diversity of 

riverine habitat. Shortnose sturgeon are found from the fast-moving freshwater riverine 

environment downstream and, into the offshore marine environment of the continental shelf. 

The shortnose sturgeon is the smallest of the three sturgeon species that occur in eastern North 

America, having a maximum known total length of 143 cm and weight of 23 kg. Growth rate and 

maximum size vary with latitude, with the fastest growth occurring among southern populations. 

Maximum known age is 67 years for females, but males seldom exceed 30 years of age. Sex ratio 

among young adults is 1:1 but changes to a predominance of females (4:1) for fish larger than 90 

cm fork length. 

Males and females mature at the same length (45 to 55 cm fork length) throughout their range. 

However, age of maturation varies from north to south due to a slower growth rate in the north. 

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Males may mature at 2 to 3 years of age in Georgia, at age 3 to 5 from South Carolina to New 

York, and at age 10 to 11 in the St. John River, Canada. Females exhibit a similar trend and 

mature at age 6 or younger in Georgia, at age 6 to 7 from South Carolina to New York, and at age 

13 in the St. John River. Age of first spawning in males occurs 1 to 2 years after maturity, but 

among females is delayed for up to 5 years. Approximate age of a female at first spawning is 15 

years in the St. John River, 11 years in the Hudson and Delaware Rivers, 7 to 14 years in the 

South Carolina rivers, and 6 years or less in the Altahama River, Georgia. Generally, females 

spawn every three years, although males may spawn every year. 

Shortnose sturgeon are benthic feeders. Juveniles are believed to feed on benthic insects and 

crustaceans. Molluscs and large crustaceans are the primary food of adult shortnose sturgeon. 

Distribution and Abundance 

The shortnose sturgeon is anadromous, living mainly in the slower moving riverine waters or 

nearshore marine waters, and migrating periodically into faster moving fresh water areas to 

spawn. One partially landlocked population is known in the Holyoke Pool, Connecticut River, 

and another landlocked group may exist in Lake Marion on the Santee River in South Carolina. 

Shortnose sturgeon occur in most major river systems along the eastern seaboard of the United 

States. In the southern portion of the range, they are found in the St. Johns River in Florida; the 

Altamaha, Ogeechee, and Savannah Rivers in Georgia; and, in South Carolina, the river systems 

that empty into Winyah Bay and the Santee/Cooper River complex that forms Lake Marion. Data 

are lacking for the rivers of North Carolina. In the northern portion of the range, shortnose 

sturgeon are found in the Chesapeake Bay system, Delaware River from Philadelphia, 

Pennsylvania to Trenton, New Jersey; the Hudson River in New York; the Connecticut River; the 

lower Merrimack River in Massachusetts and the Piscataqua River in New Hampshire; the 

Kennebec River in Maine; and the St. John River in New Brunswick, Canada. 

Major Threats and Impacts 

Construction of dams and pollution of many large northeastern river systems during the period of 

industrial growth in the late 1800's and early 1900's may have resulted in substantial loss of 

suitable habitat. In addition, habitat alterations from discharges, dredging or disposal of material 

into rivers, or related development activities involving estuarine/riverine mudflats and marshes, 

remain constant threats. 

Commercial exploitation of shortnose sturgeon occurred throughout its range starting in colonial 

times and continued periodically into the 1950's. 

Conservation and Recovery Activities 

Placing the species on the endangered species list resulted in a great deal of research on the 

species in the northern river systems. NMFS will publish a recovery plan in December 1998 

outlining actions that need to be taken in order to recover the species including: a rangewide 

genetic assessment; determination of endangered and threatened population size thresholds; 

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status reviews for each of the individual rivers that shortnose sturgeon inhabit and ensuring that 

actions taken by Federal agency do not jeopardize the survival of shortnose sturgeon. 

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Listed Species Status 

Johnson’s Sea Grass: 

Halophila Johnsonii 

Listing Date: September 14, 1998 

Johnson's seagrass has a very limited distribution 

and it is one of the least abundant seagrasses 

within its range. The species is only known to 

reproduce asexually and may be limited in 

distribution because of this characteristic. It plays 

a major role in the viability of benthic resources 

and has been documented as a food source for 

endangered West Indian manatees and threatened 

green turtles. NMFS is continuing to conduct ecological research on the species to better 

understand its life history and to use in conservation decisions affecting the seagrass ecosystems. 

Species Biology 

Identifying characteristics of Johnson's seagrass include smooth marginated, spatulate foliage 

leaves in pairs 0.5-2.5 cm long, a creeping rhizome with petioles, sessile (attached to their bases) 

female flowers, and longnecked fruits. The male flowers are unknown. Outstanding differences 

between Johnson's seagrass and other similar species are its distinct asexual reproductive 

characteristics and leaf morphology. 

Distribution and Abundance 

Johnson's seagrass is found in disjunct and patchy distribution along the east coast of Florida 

from central Biscayne Bay to Sebastian Inlet. The largest patches have been documented inside 

Lake Worth Inlet. The southernmost distribution is reported to be in the vicinity of Virginia Key 

in Biscayne Bay. The species has been found in coarse sand and muddy substrates and in areas of 

turbid waters and high tidal currents. 

Major Threats and Impacts 

Johnson's seagrass is the rarest species of its genus, has limited distributional characteristics, 

restricted reproductive capacity (being asexual), and is dependent on substrate stability. Potential 

for continued existence and recovery may be limited due to habitat alteration by a number of 

human and natural perturbations. Such perturbations include (1) prop scoring, (2) dredging, (3) 

storm action, (4) siltation and (5) altered water quality. 

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Alteration and subsequent destruction of the benthic community due to boating activities, 

propeller scoring and anchor mooring has been observed in Johnson's seagrass sites. Such 

activities result in breaking root systems, severing rhizomes and significantly reducing the 

physical stability of this ecosystem. Dredging redistributes sediments, buries plants and destroys 

bottom topography. Some abundant populations are located in close proximity to inlets, and are 

likely to experience erosional forces and siltation associated with severe storms. During 

hurricanes, storm surge may scour and redistribute sediments, thereby eroding or burying existing 

populations. 

Siltation due to human disturbance and increased land-use can also threaten viability of the 

species. Degradation of water quality due to human impact is also a threat to the viability of 

ecologically important seagrass communities. Nutrient over enrichment, caused by inorganic and 

organic nitrogen and phosphorus loading via urban and agricultural land run-off, can stimulate 

increased algal growth that may smother Johnson's seagrass by shading rooted vegetation and 

diminishing the oxygen content of the water. 

Conservation Efforts 

On September 15, 1993, NMFS published a proposed rule to list Johnson's seagrass as a 

threatened species (58 FR 48326). Designation of critical habitat was subsequently proposed on 

August 4, 1994 (59 FR 39716). A public hearing on both the proposed listing and critical habitat 

designation was held in Vero Beach, Florida on September 20, 1994. The public comment period 

was reopened until October 13, 1994, to include comments on both of the proposed actions. 

Since publication of the proposed rule, additional information has been made available to NMFS 

that supplements available data on the status and distribution of Johnson's seagrass. This 

information was reviewed in a technical workshop held in St. Petersburg, Florida in November 

1996, and was summarized in a workshop proceedings submitted to NMFS on October 15, 1997. 

In addition, genetic studies confirming and supporting information presented in the proposed rule 

regarding the species separation of Johnson's seagrass have been published; peer review 

comments on the proposed rule have been received; and a report summarizing several years of 

surveys for Johnson's seagrass within the Indian River Lagoon has been completed . 

On September 14, 1998 (63 FR 49035) NMFS published the final rule listing Johnson's seagrass 

as threatened under the Endangered Species Act of 1973. The proposed designation of critical 

habitat will be addressed in a separate Federal Register notice and additional comments will be 

solicited at that time. 

NMFS has appointed a recovery team which expects to develop a draft recovery plan by 

September, 2000. 

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Candidate Species Explanation and
 

Species Status Discussions
 

A “candidate species” is, as its name implies, a candidate for listing under the Endangered 

Species Act (ESA). More specifically, it is a species or vertebrate population for which reliable 

information is available that a listing under the ESA may be warranted. There are no mandatory 

Federal protections required under the ESA for a candidate species. NMFS urges voluntary 

protection of candidate species. 

The candidate species list is used to provide advance notification to the public that specific 

marine and anadromous species (and vertebrate populations) may warrant listing in the future. 

This can help the species and the public in two ways: Environmental planners and developers can 

locate and design long-term projects to minimize impacts to candidate species, reducing the 

likelihood that these projects will require modification later in the event of a species listing . The 

candidate species could be benefitted if voluntary conservation measures are undertaken to 

alleviate threats. 

On July 14, 1997 (62 FR 134), NMFS revised its list of candidate species. Previous revisions of 

the list occurred in 1988 and June 11, 1991 (56 FR 26797). NMFS removed 37 species from the 

list. The status of four species had changed. While NMFS determined that the bottlenose dolphin 

is depleted under the Marine Mammal Protection Act on April 6, 1993, it also determined that it 

did not warrant listing under the ESA (58 FR 17789). The Saimaa seal was listed as endangered 

on July 28, 1993 (58 FR 40538). FWS listed the Delta smelt and the tidewater goby as threatened 

on March 5, 1993 (58 FR 12854) and February 4, 1994 (59 FR 5494), respectively. Six marine 

mammals, the flatback turtle, and the giant and southern giant clams were deleted from the list 

because they are foreign species for which significant proactive conservation efforts are unlikely 

to be stimulated due to inclusion in the candidate species list. 

Additionally, there were insufficient data to determine population trends for the northern 

bottlenose whale and the starlet sea anemone, and they were removed from the list. Ten fish 

species were removed from the list because the information available to NMFS did not meet the 

more stringent standard of documentation now required for a candidate designation. Also, ten 

coral species were deleted because the information available indicates declines in certain 

populations, but not throughout the species’ ranges. Corals are invertebrates, and the ESA only 

allows invertebrates to be listed at the species level, and not at the population level. 

As a result of the 1997 revision, 15 new species for which reliable information is available to 

NMFS were added to the list of candidate species. 

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It is important to note that this list is limited by the information available. Therefore, it does not 

encompass all declining marine and anadromous species that may warrant listing in the future. 

Moreover, inclusion of a species on the candidate list does not create a higher listing priority for 

that species. As appropriate, NMFS will initiate a status review for any species or vertebrate 

population of concern, regardless of whether it is a candidate species, and the public may petition 

to list any species or vertebrate population. Inclusion in the candidate species list is intended to 

stimulate voluntary conservation efforts, which, if effective, can result in a lower likelihood of an 

ESA listing. 

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Nassau Grouper: Epinephelus 

striatus 

The Nassau grouper was a new addition to the 1991 

candidate species list. It is a tropical western 

Atlantic serranid that is an extremely popular food 

fish, resulting in its declining status. 

Species Biology 

The Nassau grouper grows to about 100 cm (3 ft) 

and 25 kg (55 lbs). It is a top-level predator found from inshore to about 100 m. Adults are 

generally found near shallow high-relief coral reefs and rocky bottoms to a depth of at least 90 

m.; juveniles (25-150 mm TL) have been found in and around coral clumps covered with 

macroalgae (Laurencia spp.) and over seagrass beds. Adults lead solitary lives outside of 

spawning aggregations. 

Nassau grouper exhibit no sexual dimorphism in body shape or color. They are characterized by 

4-5 irregular dark stripes on a pale tan or gray body, black dots around eye, a large black saddle 

on the caudal peduncle and a wide “tuning-fork” pattern on forehead. Nassau grouper, like most 

fish, can camouflage its body by changing color to match its surrounding environment. Although 

Nassau grouper were initially characterized as protogynous (changing sex from female to male) 

hermaphrodites, recent investigation indicates that Nassau grouper may not be strictly 

protogynous. Scientists have determined that Nassau grouper may display gonochorism (separate 

sexes), with potential for sex change, on the basis of histological and demographic data and the 

nature of the mating system. 

Changes in the Nassau grouper diet by age/size have been reported. It has been determined that 

juveniles feed mostly on crustaceans, while adults (>30 cm) forage mainly on fish. Nassau 

grouper usually forages alone and is not a specialized forager. 

Spawning Aggregations 

Nassau grouper reproduce in site-specific spawning aggregations. Spawning aggregations of a 

few dozen up to perhaps thousands of individuals have been reported from the Bahamas, 

Jamaica, Cayman Islands, Belize, and the Virgin Islands. These aggregations occur in depths of 

20-40 m at specific locations of the outer reef shelf edge always in December and January around 

the time of the full moon in waters 25-26 oC. The synchrony of the spawning and the full moon 

is thought to help the fish use visual cues to migrate to common spawning areas. 

Distribution & Abundance: 

The Nassau grouper is distributed throughout the islands of the western Atlantic including 

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Bermuda, the Bahamas, southern Florida and along the coasts of central and northern South 

America. It is not known from the Gulf of Mexico except at Campeche Bank off the coast of the 

Yucatan, at Tortugas, and off Key west. 

Major Threats and Impacts 

The Nassau grouper is an important finfish in the food fish industry of the West Indies and 

Caribbean - it is the most important finfish in the Bahamas, second only to lobster and conch. It 

is usually caught by hook and line, traps, or speargun. Because Nassau grouper spawn at historic 

areas, they are easily targeted during reproduction, which removes the reproductively active 

members of the group, possibly preventing successful spawning. 

Conservation Programs 

The NMFS, under the authority of the Magnuson-Stevens Fisheries Act, has classified the 

Nassau grouper as “overfished” in its October 1998, “Report to Congress on the status of 

Fisheries and Identification of overfished Stocks”. 

Commercial or recreational retention of Nassau grouper is prohibited under the regulations 

promulgated to implement the Amendments to the South Atlantic Snapper-Grouper Fishery 

management plan as proposed by the South Atlantic Fisheries Management Council. 

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Warsaw Grouper: 

Epinephelus Nitrigus 

The Warsaw grouper was added to the 

candidate species list in 1997. Although there 

is very limited information available, it follows 

patterns similar to the other groupers on the 

candidate species list ( e.g. - Jewfish, Nassau 

Grouper). 

Species Biology 

The color is grayish brown to dark red-brown background with numerous small, irregular white 

blotches on the sides. The fish can obtain weights of over 300 lbs. The color appears much 

lighter around the nape and along the posterior margin of the operculum. All of the fins are dark 

brown, except the white-splotchy spiny portion of the dorsal. Very little information is available 

about the reproduction of the Warsaw grouper, however, eggs and larvae are presumed to be 

pelagic. Like other Epinephelus groupers, the Warsaw is long-lived and has a slow growth rate. 

It is believed that these fish can attain ages exceeding 25 years. The grouper's large mouth 

enables it to engulf prey whole after capturing it in ambush or after a short chase. Crabs, shrimps 

and fishes are major foods. 

Distribution and Abundance 

The Warsaw grouper is a very large fish found on the deepwater reefs of the southeastern United 

States. Warsaw grouper range from North Carolina to the Florida Keys and throughout much of 

the Caribbean and Gulf of Mexico to the northern coast of South America. The species inhabits 

deepwater reefs on the continental shelf break in waters 350 to 650 feet deep. 

Major Threats and Impacts 

The major threat to the Warsaw grouper is mortality as a result of fishing. 

Conservation Programs 

NMFS has designated this species as "overfished" as defined by the Magnuson-Stevens Fisheries 

Act. Quotas have been placed restricting the number of Warsaw groupers that may be landed to 

1 fish/trip/vessel. 

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Speckled Hind: Epinephelus 

drummondhayi 

The speckled hind was added to the candidate 

species list in 1997. It is considered one of the 

most beautifully colored groupers caught off 

the southeastern United States in the speckled 

hind. The hind gets its common name from 

the multitude of tiny white spots that cover the 

reddish-brown head, body and fins. 

Species Biology 

Like other epinepheline groupers, speckled hind are protogynous hermaphrodites, which means 

they begin life as females and as they mature they become males. Most of the larger, older fish 

are males. Females reach sexual maturity at around four to five years of age. Spawning takes 

place offshore from July through September. The fertilized eggs are pelagic, and the newly 

hatched young are commonly found on the surface before migrating to the bottom. 

Speckled hind generally engulf their prey whole. The fish opens its mouth and extends the gill 

covers rapidly to draw in a current of water, thus inhaling the food. Groupers are also known to 

pursue their prey and strike it. Prey items for the speckled hind include: fishes, crabs, shrimps 

and mollusks that inhabit the hard bottom. 

Distribution and Abundance 

Speckled hind inhabit warm, moderately deep waters from North Carolina to Cuba, including 

Bermuda, the Bahamas and the Gulf of Mexico. The preferred habitat is hard bottom reefs in 

depths ranging from 150 to 300 feet, where temperatures are from 60 to 85 degrees F. 

Major Threats and Impacts 

The major threat to the speckled hind is mortality as a result of fishing. 

Conservation Programs 

NMFS has designated this species as "overfished" as defined by the Magnuson-Stevens Fisheries 

Act. Quotas have been placed restricting the number of speckled hind that may be landed to 1 

fish/trip/vessel. 

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Jewfish: Epinephelus Itajara 

The jewfish was added to the candidate 

species list in 1991 for the region of North 

Carolina southward to the Gulf of Mexico, 

which encompasses the entire range of this 

species in US waters. All harvesting of the 

jewfish in the Gulf of Mexico and Southern 

Atlantic Federal waters has been prohibited 

since 1990 and in the Carribean since 1993. 

Stocks are not expected to recover quickly
 

because of the late age of maturity for this species (4-7 years). 

Species Biology 

The jewfish is the largest of the western north Atlantic groupers. It can reach about 455 kg (800 

lbs.) Males range in size from 795-2057 mm TL and females from 338-2155 mm TL. Jewfish 

can be easily distinguished by the following features: terete shape, broad head, small eyes, and 

short dorsal spine. They tend to have brownish-yellow or greenish-gray bodies and small black 

spots on their fins. Although jewfish are very vulnerable to cold waters and red tide, they are one 

of the only groupers that can live in brackish waters. Fish taken from an exploited population 

were aged from 0-37 years, but it is likely that jewfish live much longer than 40 years if left 

unexploited. 

Distribution and Abundance 

Historically, jewfish were found in tropical and subtropical waters of the Atlantic Ocean, both 

coasts of Florida, and from the Gulf of Mexico down to the coasts of Brazil and the Caribbean. 

Most adults are found in shallow waters, the deepest being about 150 feet. Spawning occurs at 

aggregation sites in July through September over full moon phases. Fish may move up to 100 

km from inshore reefs to the offshore spawning aggregations in numbers of up to 100 or more on 

ship wrecks, rock ledges, and isolated patch reefs along the southwest coast of Florida. 

Aggregations declined in the 1980's from 50-100 fish to less than 10 per site. Since the harvest 

prohibitions imposed in 1990 and 1993, aggregations have rebounded somewhat to 20-40 fish 

per site. When jewfish are not on their spawning aggregations, they are dispersed along shallow 

reefs. Historically, they were abundant in very shallow water, often associated with piers and 

jetties along the Florida Keys and southwest coast of Florida. They are no longer abundant in 

these shallow areas. 

Juvenile jewfish have been found along shallow mangrove shorelines, underneath mangrove prop 

roots. Their historical center of abundance is in the Ten Thousand Islands area of southwest 

Florida. 

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Major Impacts and Threats 

The most likely cause of drastic declines was the heavy fishing pressure on aggregations. When 

large numbers of normally dispersed fish are concentrated at predictable areas and times, they are 

highly vulnerable to overexploitation. Fishing on spawning aggregations also removes many 

reproductive individuals before they have had the opportunity to spawn. Many jewfish were 

caught between the ages of 9-15 years, meaning that individuals only lived through only a few 

reproductive years before being captured. Their slow growth rate, long lives, and large size at 

sexual maturation has made them especially susceptible to overfishing. Finally, their genetic 

diversity could be impacted when the fishing mortality rate is greater than the natural mortality 

rate. 

Conservation Programs 

The NMFS, under the authority of the Magnuson-Stevens Fisheries Act has classified the jewfish 

as “overfished” in its October 1998, “Report to Congress on the Status of Fisheries and 

Identification of Overfished Stocks”. 

Commercial or recreational retention of jewfish is prohibited under the regulations promulgated 

to implement the Amendments to the South Atlantic Snapper-Grouper Fishery management plan 

as proposed by the South Atlantic Fisheries Management Council. 

The main group researching the jewfish for NMFS is the Southeast Fisheries Science Center 

(SEFSC). The SEFSC has three main goals regarding jewfish: 

1. To quantify the presence of juveniles in their nursery habitat of mangrove shorelines and the 

level of abjection of those habitats. 

2. To enforce all fishing prohibitions. 

3. To build an outreach/educational program to teach the need to protect the species. 

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Opossum Pipefish: 

Microphis brachyurus 

lineatus 

The opossum pipefish was added to 

the candidate species list in 1997. 

The predominant areas in which 

there is concern for this pipefish is in the Indian River Lagoon of Florida. NMFS initiated a 

status review of this species in 1998 to determine if listing under the ESA is warranted. 

Species Biology 

The opossum pipefish has several very unique characteristics. It is the only tropical western 

Atlantic pipefish that broods eggs on its trunk rather than its tail. Brooding male opossum 

pipefish have been captured in tributaries to the Indian River Lagoon, Florida, during all months 

except January and February. The opossum pipefish is considered to be a large pipefish with a 

standard length (SL) of about 194 mm (7.64 in). It has a long snout– 1.5-2.0 in. head length– 

and about 40 rings on its trunk and tail. The opossum pipefish is also very colorful. The most 

conspicuous color is the brilliant red lower half of the snout overlaid with alternating jet black 

bands. Most of its head is sienna brown with dark red blotches on each lateral trunk ring, small 

silver stripes on its mid-side, and a red caudal fin with one central dark stripe. 

Distribution and Abundance 

The opossum pipefish is a circumtropical species whose breeding adults are only found in 

freshwater associated with certain vegetation (usually panic grass (Panicum sp.) and smart weed 

(Polygonum spp.)). Predictable breeding adult populations are limited to tributaries of the Indian 

River Lagoon, the Sebastian, St. Lucie and Loxahatchee rivers. This specifically limits the adult 

population to this coastal area of Florida adjacent to the warm Florida Current. All of these areas 

receive freshwater from inland and upland sources as part of an extensive coastal flood control 

system. 

Major Threats and Impacts 

The main reason that the opossum pipefish is becoming very rare is that its habitat is 

disappearing. This is a result of several factors. First, continuous human settlement limits the 

areas in which these pipefish live. The rapid and continual growth of the coastal human 

population displaces pipefish habitat. Because these pipefish need access to very specific 

vegetation types and to freshwater, they have few places they can migrate to. Furthermore, 

migration is limited because of flood structures which block rivers and canals that offer pipefish 

habitat. Lastly, herbicide treatment, which also destroys vegetated pipefish habitat, provides a 

potential threat for this limited Florida population. 

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Conservation Programs 

Although the opossum pipefish is not a very well-known fish and the numerous threats to its 

extinction have not been highly publicized, there are groups who have extensively studied the 

opossum pipefish. They include the Harbor Branch Oceanographic Institution and the Florida 

Museum of Natural History. 

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Mangrove Rivulus: Rivulus 

marmoratus 

One of the new additions to the 1997 candidate 

species list was the mangrove rivulus. This is the 

only native species of the genus Rivulus that can be 

found in North America. It is widely distributed but 

locally rare in Florida waters. In 1998, NMFS 

initiated a status review to determine if listing this 

species under the ESA is warranted. 

Species Biology 

The mangrove rivulus has a long slender body with dark brown to maroon coloration. On the 

sides of the body there may be small black dots. The maximum length is 60 mm total length 

(TL), although the average is about half that at 24 mm TL. The mangrove rivulus is unique 

among vertebrates in its method of reproduction. It is the only known vertebrate self-fertilizing 

hermaphrodite. This means that both the eggs and the sperm are produced by one parent, and 

the young are genetically identical to the parent. 

Distribution and Abundance 

The mangrove rivulus can be found from south-central Florida down south through the West 

Indies to coastal areas of South America. It can also be found throughout the waters of Cuba, the 

Bahamas, Jamaica, and Yucatan. On the east coast of Florida, the preferred micro-habitat is the 

land crab burrow. In south Florida and on the west coast the preference is for stagnant pools and 

old mosquito ditches in mangrove forests. 

Major Threats and Impacts 

This species is extremely vulnerable to habitat modification, environmental alteration, and 

human development/encroachment. Much of the suitable habitat has been isolated and 

fragmented as a result of the destruction of mangroves and impounding of high marsh for 

mosquito control. Irregular population decreases have occurred because of unusually cold 

waters. The mangrove rivulus is limited at the northern end of its range because of cold waters. 

Although it is obvious that the population of this species has been dramatically reduced, it is 

difficult to evaluate the distribution and status because of natural rarity and its secretive 

tendencies. 

Conservation Programs 

Currently, there is limited information available on the mangrove rivulus. NMFS has begun a 

status review and the state of Florida lists the mangrove rivulus as a species of special concern. 

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Atlantic salmon: Salmo 

salar 

One distinct population segment (DPS) 

composed of seven river populations of 

Atlantic salmon was proposed for listing 

as threatened on September 29, 1995. 

The seven Maine rivers are the following: 

Sheepscot, Ducktrap, Narraguagus, Pleasant, Machias, East Machias, and Dennys rivers. Because 

the possibility exists that additional populations could be added to the seven rivers DPS in the 

future, and for purposes of future conservation activities, the Services have renamed the seven 

rivers DPS the Gulf of Maine DPS. Other Atlantic salmon populations will be added to the Gulf 

of Maine DPS if they are found to be naturally reproducing and to have historical, rivers specific 

characteristics. The area within which populations meeting these criteria for addition to the DPS 

would most likely be found is from the Kennebec River north to, but not including, the St. Croix 

River. 

NMFS and U.S. Fish and Wildlife Service (USFWS) determined that the Atlantic salmon 

populations in these seven rivers are, as a group, reproductively isolated and discrete. Naturallyreproducing Atlantic salmon in U.S. rivers are substantially reproductively isolated from those in 

Canada. A critical factor in determining the significance of the river populations of U.S. Atlantic 

salmon was the continuous persistence of a substantial component of native stock reproduction. 

The continuous presence of U.S. Atlantic salmon in indigenous habitat provides evidence that 

important local adaptations have persisted. At present, differences are subtle and difficult to 

assess because of low abundance. Within the U.S., Atlantic salmon populations exhibit strong 

fidelity to natal streams. An examination of U.S. populations of Atlantic salmon provides 

evidence of their distinctness from stocks in Canada and northern Europe. 

The original range of Atlantic salmon in the United States was from the Housatonic River in 

Connecticut, north to U.S. tributaries of the St. John River in New Brunswick, Canada. The 

historic Atlantic salmon run in the United States has been estimated to have approached 500,000 

fish. The species began to disappear from U.S. rivers 150 years ago and currently, only remnant 

populations occur in a limited number of rivers in Maine. Throughout the past 24 years, the 

Dennys and Narraguagus rivers have had returns that averaged 20 percent of the escapement 

goal, and the Pleasant, Sheepscot, and Machias rivers have had returns that averaged between 10 

and 12 percent of their escapement goals. However, recent downward trends in abundance have 

put most of these seven rivers at less than 10 percent of their respective escapement goals. 

Species Biology 

Anadromous Atlantic salmon have a relatively complex life history that extends from spawning 

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and juvenile rearing in freshwater rivers to extensive feeding migration in the high seas. Adult 

Atlantic salmon ascend the rivers of New England beginning in spring, a migration that peaks in 

June and continues into the fall. Juvenile salmon feed and grow in the rivers from one to three 

years before undergoing smoltification and migrating to the ocean. Atlantic salmon of U.S. origin 

are highly migratory, undertaking long marine migrations between the mouths of U.S. rivers and 

the northwest Atlantic Ocean where they are widely distributed seasonally over much of the 

region. Most Atlantic salmon of U.S. origin spend two winters in the ocean before returning to 

freshwater to spawn. Those that return after only one year are called grilse. 

Distribution and Abundance 

The populations of anadromous Atlantic salmon present in the Gulf of Maine Distinct Population 

Segment represent the last wild remnant of U.S. Atlantic salmon. Restoration efforts for Atlantic 

salmon are ongoing in other watersheds where the locally-adapted stocks have been extirpated. 

Major Threats and Impacts 

The construction of hydropower dams with either inefficient or non-existent fishways was a 

major cause for the decline of U.S. Atlantic salmon. Dams adversely impact Atlantic salmon by 

impeding both their upstream and downstream migration, increasing predation, altering the 

chemistry and flow pattern of rivers, increasing water temperature, and reducing available flow 

downstream. Currently there are no hydropower dams on the seven rivers that have the potential 

to adversely impact the species. Beaver and debris dams have been documented on these rivers 

and may partially obstruct passage. 

One of the predominant land uses of the central and northern coastal Maine watersheds is the 

growth and harvest of forest products. Forest management practices can cause numerous shortand long-term negative impacts to Atlantic salmon, including siltation, shade reduction, and 

increased water temperature. Another significant land use in eastern Maine watersheds is 

lowbush blueberry agriculture. In addition, interest in cranberry cultivation is increasing . These 

agricultural activities can impact Atlantic salmon through water extractions and diversions and 

pesticide application. Currently regulatory mechanisms are in place such that forest practices and 

agricultural practices are not considered a major threat to Atlantic salmon. 

Historically, the marine exploitation of U.S. origin Atlantic salmon occurred primarily in foreign 

fisheries. U.S. origin Atlantic salmon have been documented in the harvests of West Greenland, 

New Brunswick, Nova Scotia, Newfoundland, and Labrador. The U.S. is a party to the North 

Atlantic Salmon Conservation Organization (NASCO) which was formed for the purpose of 

managing salmon through a cooperative program of conservation, restoration and enhancement 

of North Atlantic stocks. Since 1987 there has been a Fishery Management Plan in place which 

prohibits the possession of Atlantic salmon in the Exclusive Economic Zone. There is currently a 

limited catch and release fishery for Atlantic salmon in these seven Maine rivers. 

Aquaculture facilities raising Atlantic salmon in net pens are located within 20 km of the mouths 

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of five of the rivers within the DPS. Atlantic salmon that have escaped from aquaculture pens are 

known to have entered some of these rivers. The escape of fish from Atlantic salmon aquaculture 

operations could pose a threat to the genetic integrity of Atlantic salmon within the DPS. In 

addition, concentrations of aquaculture salmon could increase the vulnerability of wild stocks to 

disease. Scientific evidence suggests that low natural survival in the marine environment is a 

major factor contributing to the decline of Atlantic salmon throughout North America. It appears 

that survival of the North American stock complex of Atlantic salmon is at least partly explained 

by sea surface water temperature, during the period when Atlantic salmon are concentrated in 

winter months in habitat at the mouth of the Labrador Sea and east of Greenland. 

NMFS and USFWS outlined the above factors for decline in a Status Review prepared to support 

the proposed rule. The proposed rule contained a special provision pursuant to section 4(d) of the 

ESA to invite the State of Maine to prepare a Conservation Plan for Atlantic salmon and 

therefore remain as the lead manager of the species. In order to draft that Conservation Plan, the 

Governor of Maine convened a Task Force composed of state agency representatives, private 

industry, conservation groups, and concerned stakeholders. The Conservation Plan contains a 

number of actions and measures to reduce potential impacts to Atlantic salmon from recreational 

fishing, agriculture, aquaculture, and forestry. NMFS and USFWS withdrew the proposed rule to 

list on December 18, 1997. In making this determination, the Services considered the status of 

the Gulf of Maine DPS and took into account the efforts being made to protect the species 

including the development of the State of Maine's Conservation Plan, the extent of 

implementation of the Plan, private and Federal efforts to restore the species, and international 

efforts to control ocean harvest through NASCO. The Services committed to making the annual 

report on Conservation Plan implementation available to the public for review and comment and 

identified actions or developments that would cause them to reinitiate the listing process. 

Atlantic salmon status will be reviewed annually and, if necessary, NMFS will reinitiate the 

listing process. 

In a Notice also published in the Federal Register on December 18, 1997, NMFS stated that it 

had placed the Atlantic salmon on the candidate species list to aid in public awareness about the 

species. 

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Alabama Shad: Alosa 

alabamae 

The Alabama shad was added to the candidate 

species list in 1997. This species has 

experienced significant population declines in 

the last forty years as an increased number of 

dams have been built for navigation, 

hydroelectric generation and flood control. These dams block this shad’s upstream migration to 

suitable spawning sites. Although these dams are not the only threat to the species, they are the 

most prevalent. 

Species Biology 

The Alabama shad is often misidentified as the Skipjack herring. There are, however, numerous 

differences in features such as the Alabama shad’s pointed snout, an included lower jaw (may be 

slightly projecting, the jaw on the skipjack protrudes in front of the upper jaw) and many more 

gill rakers on the lower arm of the first gill raker arch. The average age of spawning fish is two 

years. Young remain in fresh water for the first six to eight months of their lives. Thirty-eight 

percent are repeat spawners, as is apparent by spawning marks on the shad’s sides. Adults leave 

the spawning area soon after spawning is complete. The Alabama shad lives to about six years. 

Females are larger than males; the male’s total length range is 90 to 419 mm and the female’s is 

360 to 457 mm. 

Distribution and Abundance: 

The Alabama shad is an anadromous species that spawns in large flowing rivers from the 

Mississippi River to the Suwannee River of Florida. The largest existing population occurs in the 

Apalachicola River. Populations also persist in the Pascagoula River drainage of Mississippi and 

the Mobile River drainage of Alabama. Fish enter freshwater during the spawning season 

(January to April) when water temperature reaches 19 to 22° C. Spawning is known to occur 

over sand, gravel, and rock substrates in a moderate current in the Apalachicola River below Jim 

Woodruff Lock and Dam and in the Choctawhatchee and Conecuh rivers in south central 

Alabama. 

Major Threats and Impacts 

The great decline in the status of the Alabama shad in Alabama is mostly due to a series of high 

lift navigating dams in the Alabama and Tombigbee rivers which block spawning migration to 

the Mobile Basin. 

Other threats to the shad include poor water quality and commercial and navigational dredging of 

sand bars used for spawning. 

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In the past, commercial fishing was a threat to the shad. During the 1800's, this species 

supported a commercial fishery on the Ohio River. In 1899, approximately 6,950 pounds of 

Alabama shad were taken from the river, and in 1903 approximately 8,750 pounds. 

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Dusky Shark: Carcharhinus 

obscurus 

The dusky shark was added to the candidate species 

list in 1997. Although not stated in the Federal 

Register notice, only the population in the Northwest 

Atlantic Ocean are considered as candidate species. 

Species Biology21 

The dusky is a large, fairly slender shark with a low 

interdorsal ridge. The rounded snout is shorter or equal to the width of the mouth. The first 

dorsal fin originates over or near the free rear tips of the pectoral fins. The color is bronzy gray 

to blue gray above with white ventrally. 

Carcharhinus obscurus is a large shark that reaches 360 cm and 180 kg. In the northwestern 

Atlantic, males attain sexual maturity at 231 cm (fork length) and 19 years of age, while females 

mature at 235 cm (fork length) and 21 years. Similar sizes at maturity have been reported from 

South Africa and Australia. The oldest dusky shark reported from vertebral aging studies is 37 

years, although they are believed to live to a maximum of 40 to 50 years. 

Tagging studies in the southwestern Indian Ocean, the western North Atlantic Ocean and the 

Gulf of Mexico, and the southeastern Indian Ocean have all shown that C. obscurus is a highly 

migratory species. The longest distance between tagging and recapture is 2,052 nautical miles, 

and the longest period at liberty 15.8 years. Movements normally show seasonal patterns, with 

adults moving into more temperate areas as temperatures rise in summer. Movements of adults 

are larger than those of neonates and juveniles. 

The dusky shark is viviparous, with litters normally ranging in size from 3 to 14. There is little 

information available to estimate accurately the gestation period, although recent work has 

suggested that it may be as long as 22 to 24 months. The lack of large yolky ova in the ovary of 

late-term pregnant C. obscurus indicates that there may be a one year resting period between 

birth and mating, making the reproductive cycle at least 3 years long. 

Major nursery areas for C. obscurus have been identified off the Natal coast of South Africa, the 

New Jersey to South Carolina coast of the United States, and the southwest coast of Australia. 

The neonates occur in nearshore waters in all of these nursery areas, but do not enter lower 

salinity areas. 

21Adapted from a DRAFT species status report prepared by the IUCN Shark Specialist Group. Compiled by Merry Camhi, National 

Audubon Society; Jack Musick, Virginia Institute of Marine Sciences; and Colin Simpfendorfer, Western Australia Marine Research 

Laboratories - with additional input from NMFS-HMS. 

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C. obscurus has a varied diet that includes bony fishes, cartilaginous fishes (sharks and rays) and 

squid. Young sharks mostly consume small pelagic bony fishes (e.g., sardines and anchovies) 

and squid. With increasing size larger fish (e.g., groupers, jacks) and elasmobranchs (e.g., 

dasyatids, Raja spp., Rhinobatus spp., squatinids, carcharhinids, mustelids and squalids) become 

more important in the diet. As a common apex predator C. obscurus plays an important (but 

poorly studied) role in the marine ecosystem. In the western Atlantic, the dusky has always been 

less abundant than some other species of carcharhinid sharks with which it is sympatric, such as 

the sandbar shark. This seems to be in keeping with its larger size and higher trophic position. 

Recent demographic analyses of C. obscurus in the western Atlantic has generated estimates of 

the annual rate of population increase of 2.8% and 5.57%. Both of these estimates are for the 

population without fishing mortality and assume a two-year reproductive cycle. Given that it is 

now thought that the reproductive cycle lasts three years these population increase rates may be 

even lower. The low rates of population increase highlight the need for conservative 

management of fisheries that capture C. obscurus. 

*Carcharhinus obscurus estimated life history parameters 

Age and/or size at maturity f: 21 yrs (235 cm); m: 19 yrs (231 cm) 

Longevity/maximum size 40-50 yrs/360 cm (180 kg) 

Gestation time 22-24 months 

Reproductive periodicity 3 years 

Average annual fecundity or litter 

size 

3-14 pups 

Annual rate of population 

increase 

2.8% - 5.6% 

Distribution and Abundance 

This species has a wide-ranging (but patchy) distribution in warm-temperate and tropical 

continental waters. It is coastal and pelagic in its distribution, where it occurs from the surf zone 

to well offshore, and from the surface to depths of 400 m. Because it apparently avoids areas of 

lower salinities, it is not commonly found in estuaries. 

In the western Atlantic, it extends from southern New England to the Caribbean and Gulf of 

Mexico to southern Brazil. However, its distribution off Central America is poorly known. Its 

occurrence is uncertain in the eastern North Atlantic, but it has been recorded around oceanic 

islands off western Africa. These records and others from tropical insular areas may be 

misidentifications of a sibling species (C. galapagensis). In the western Indian Ocean, it occurs 

off South Africa, Mozambique, Madagascar, and possibly in the Red Sea. In the western Pacific 

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it is found in the waters of Japan, China, Vietnam, Australia, and New Caledonia. In the eastern 

Pacific, the dusky extends from southern California to Gulf of California, Revillagigedo Islands, 

and possibly Chile. 

The dusky shark undertakes long temperature-related migrations. On both coasts of the U.S., 

duskies migrate northward in summer as the waters warm and retreat southward in fall as water 

temperatures drop. The dusky shark occurs throughout Australian waters. In western Australia, 

adolescents and adults move inshore during the summer and fall, with neonates occupying 

separate inshore areas. Seasonal migrations (north in winter and south in summer) also occurs 

off South Africa. In the Indian Ocean, the young are known to aggregate in dense assemblages 

when feeding. 

Major Threats and Impacts 

Currently the principal threat to C. obscurus is from commercial and recreational shark fisheries 

off the east coast of North America, the southwest coast of Australia, and the eastern coast of 

South Africa. In each of these locations there are longline and/or gillnet fisheries that target 

sharks, including C. obscurus. In all cases these are multispecies fisheries making the 

management of a single species such as C. obscurus more difficult. Off North America the 

proportion of C. obscurus in the catch is decreasing, while fishing for more abundant species 

continues, which could drive this population toward extirpation. 

The rapid expansion of the commercial shark fishery in the U.S. in the late 1980s was fueled in 

large part by the demand for shark fins in the markets of Asia. Dusky sharks have one of the 

highest rated fins for shark fin soup because of their large size and high fin needle content 

(ceratotrichia). Although dusky meat is used domestically in the U.S., the very high value of the 

fins suggests that the decline in this dusky shark population over the past decade has been, and 

continues to be, driven by international trade in shark fins. There is little reason to believe that 

the demand for dusky shark products will lessen, especially as other fishery resources become 

increasingly depleted. 

The flesh of the young C. obscurus is highly regarded and fetches a good price on local markets. 

Fins are also sold. Assessment of the fishery using population models is difficult, and a tagging 

study has been undertaken to determine exploitation rates. Current estimates are that 18-28% of 

neonates are caught in the first year. Although this is high, assessments indicate that this level of 

exploitation may be sustainable since only a small number of year classes are targeted. 

In addition, dusky sharks are taken as bycatch in directed tuna and swordfish longline fisheries 

(as well as being targeted catch by these vessels), in tuna and swordfish gill net fisheries. In the 

Gulf of Mexico during the late 1980s, the dusky shark was the fourth most abundant species in 

the tuna longline bycatch, where medium to large dusky sharks were often shot, finned, and 

discarded. Because of its high-value fin, dusky sharks caught incidentally on tuna and swordfish 

longlines are now regularly landed rather than released. 

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Additionally, Dusky sharks are one of the most important species in the trophy shark 

tournaments held in Florida, USA. 

Status and IUCN threatened species assessment 

The dusky shark was added to the NMFS candidate species list in 1997. Declining catch rates 

for dusky sharks in the western Atlantic are a cause for concern. Recent reviews of catch and 

landings data for the large coastal shark assemblage in the western Atlantic (including dusky and 

other requiem sharks), found that by 1986 the abundance of many of the large coastal species had 

probably declined by 50-75% from 1970s levels -- even prior to the expansion of the commercial 

shark fishery in 1986 . Today the dusky shark population in the northwestern Atlantic and Gulf 

of Mexico is probably at 15-20% of its mid-1970s abundance. 

The IUCN Shark Specialist Group recently evaluated the status of C. obscurus using the new 

listing criteria for the IUCN Red List of Threatened Species. On a global basis, the dusky shark 

was determined to be "Lower risk, near threatened." However, the U.S. population in the 

Northwestern Atlantic and Gulf of Mexico was evaluated to be "Vulnerable" based on the 

decline in abundance indices. The status in Australia at this point is "Lower risk, near 

threatened." 

Conservation Programs 

Dusky shark, as part of the large coastal shark (LCS) management unit was identified as 

overfished in 1993 when the FMP was implemented. This classification was reaffirmed in the 

1997 Report to Congress. 

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Sand Tiger Shark: Odontaspis 

taurus 

The sand tiger shark is one of three species of shark 

added to the candidate species list in 1997. 

Species Biology22 

The sand tiger shark has a very stocky body and is 

light brown to greyish color above, merging to offwhite on the belly. Dark blotches or spots may 

occur on the upper two thirds of the body, particularly in juveniles. It has a conical nose, a 

dorsally flattened head, and all five gill slits are located before the pectoral fin. A small pit is 

located on the upper side of the caudal peduncle. The teeth, which are similar in both jaws, are 

long and pointed, with a small spine-like cusp on either side. The first dorsal fin is situated 

immediately in advance of the ventral fins. The two dorsal fins and the anal fin are all 

approximately the same size, and the caudal fin has an elongated dorsal lobe. 

The maximum size of the species has been given variously as ~3.2 m, ~2.75 m and ~142 kg, and 

~3.2 m and ~300 kg. Catch records from beach netting in Australia suggest that sand tiger sharks 

may grow to 4.3 m. The oldest individuals recorded in aquaria were 13 years and 16 years. 

Sand tiger sharks occur either alone or in small to medium sized schools. They have been 

observed hovering motionless just above the seabed in or near deep sandy -bottomed gutters or 

rocky caves, usually in the vicinity of inshore rocky reefs and islands, They are generally coastal, 

usually being found from the surf zone down to depths around 75 feet. However, they may also 

be found in shallow bays, around coral reefs and to depths of 600 feet on the continental shelf. 

They usually live near the bottom, but may also be found throughout the water column. 

This shark is a slow but strong swimmer that is usually more active at night. Although its body 

is more dense than the water, it has been found to swallow air at the surface and hold it in its 

stomach to maintain neutral buoyancy. 

Mating occurs between late October and the end of November. Courtship may be a lengthy 

process which involves the males inflicting nips on the female. If she is receptive, mating 

follows. If not, the male continues biting, inflicting wounds all over her body until she flees. 

22Adapted from a DRAFT species status report prepared by the IUCN Shark Specialist Group. Compiled by David Pollard and 

Adam Smith - with additional input from NMFS-HMS. 

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Full term pregnant females move southward each year during July and August to give birth in 

early spring, and then return northward. Not all migrating females are sexually active and mature 

females generally reproduce only once every two years. 

This species is ovoviviparous (meaning that they develop as unattached embryos within the 

uterus, with energy supplied by large egg yolks) as opposed to viviparous (live placental birth) or 

oviparous (laying egg cases - like skates), and usually only one or occasionally two pups are born 

per litter. This is because the remaining eggs and developing embryos are eaten by the largest 

and/or most advanced embryo in each horn of the uterus (uterine cannibalism). The gestation 

period may last from 9 to 12 months, and size at birth is relatively large, about 1 meter. 

*Odontaspis taurus estimated life history parameters 

Size at maturity 2 meters 

Maximum size 3.2-4.3 meters 

Gestation time 9-12 months 

Average annual fecundity or litter size 1-2 pups 

Distribution and Abundance 

Sand tiger (grey nurse) sharks have a broad inshore distribution. In the Western Atlantic, this 

shark occurs from the Gulf of Maine to Florida, in the northern Gulf of Mexico, in the Bahamas 

and in Bermuda. 

Major Impacts and Threats 

Sand tiger sharks have been fished throughout their range, but are of variable economic 

importance regionally. The species is highly regarded as a food fish in Japan, but not in the 

Western Atlantic. It is caught primarily with line fishing gear, but is also taken in bottom-set 

gillnets and on pelagic and bottom trawls. The meat is utilized fresh, frozen, smoked and dried 

and salted, for human consumption. It has also been used for fishmeal, oil (from its liver) and its 

fins are used for the Oriental sharkfin trade. Sand tigers are very susceptible to fisheries because 

they aggregate in large numbers at particular coastal spots at certain times of year. These 

aggregations have been targeted in the past by fisheries. 

In addition, the juvenile sand tiger sharks are most common and dependent on some of the most 

polluted estuaries of the eastern US: the Chesapeake, Delaware, and Narragansett bays and the 

Pamlico and Long Island Sounds. 

Interuterine cannibalism is another factor that makes this species vulernable, since it limits the 

litter size to one or two pups. 

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Conservation Programs 

The sand tiger shark is managed by the Highly Migratory Species Fishery Management Plan 

(FMP) under the Magnuson-Stevens Fisheries Act. Under this FMP, the shark receives full 

protection from harvest on the Atlantic coast of the US. It is illegal to commercially or 

recreationally land this species or any parts (fins, meat, jaws, etc). 

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Night Shark: Carcharhinus 

signatus 

NMFS designated the night shark as a 

candidate species in 1997. Data on this 

species are minimal because the shark is a 

deepwater shark. Most of the data available 

on this species is fishery related. 

Species Biology 

This is a tropical shark that seldom strays 

into cooler water. The green eye indicates that it is a deep-water species, usually found at depths 

greater than 150-200 fathoms during the day and 100 fathoms at night. It feeds primarily on 

fishes and shrimp. The sharks' reproduction is viviparous, which means that they give live birth 

to their young. Litter size ranges form twelve to eighteen pups. Little else is know about the 

reproductive biology of the species. 

Distribution and Abundance 

The shark has been reported in waters from Delaware south to Brazil, including the Gulf of 

Mexico. It has also been reported from West Africa. It was formerly very abundant in deep 

waters off the northern coast of Cuba and the Straits of Florida. 

Major Threats and Impacts 

The main threat to the night shark has been mortality associated with fishing. The shark is caught 

mainly on longlines in about 100 fathoms, usually at night. 

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Key Silverside: Menidia 

conchorum 

The Key silverside was designated as a 

candidate species in 1991. There is 

currently discussion in the scientific 

community as to whether the Key 

silverside should be considered a distinct species. NMFS will monitor this discussion to 

determine whether it is a unique species or whether it is actually the tidewater silverside, M. 

peninsulae. 

Species Biology 

This small fish lives in shallow, protected waters during the day, making it very difficult to 

observe. The key silverside is the smallest known species of Menidia. Its maximum size is 53 

mm (about 2 inches). It is most easily distinguished from the other species in this genus by a 

lower anal ray count, fewer branchial lateral-line scales, and fewer total vertebrae. It is believed 

that the species spawns in the middle to late winter. The silverside is a diurnal species occurring 

in swift moving schools. The fish is commonly found in shallow water among black mangrove 

rhizomes, where it is less vulnerable to predation. It feeds on microscopic animals such as 

copepods, mysids, isopods, and most importantly, insects. 

Distribution and Abundance 

This species is found in the Florida Keys, from Key West north to Long Key. Rarity within this 

area may be due to inaccessibility of the habitat to routine collecting. Because so little is known 

about the Key silverside and it appears to be rare, it has been kept on the candidate species list. 

Major Threats and Impacts 

The main threat to the Key silverside is the loss of habitat due to the fish’s association with black 

mangrove. Historically, the species was found in a few localities in the Keys: Key West; Big 

Pine, Cudjo, Rockland, Grassy and Long keys. Recent records have shown the fish's 

disappearance from Key West. 

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Atlantic Sturgeon: Acipenser 

oxyrhinchus oxyrhinchus 

The Atlantic sturgeon is a significant species both 

biologically and commercially. Biologically, this 

species has intrigued scientists with its ancestry 

leading back to the dinosaurs. Commercially, this 

species has intrigued fishermen for its highly valued 

caviar. The Atlantic sturgeon was placed on the candidate species list in 1988. An exhaustive 

status review of the species was conducted in 1998, detailing the biology, analysis of threats, 

conservation efforts, and recommendations for further studies. Upon receipt of a petition to list 

this species, a status review was conducted. The status review described the information used to 

determine that listing the Atlantic sturgeon as an endangered or threatened species is not 

warranted at this time. The National Marine Fisheries Service has retained Atlantic sturgeon on 

its list of candidate species to monitor the sturgeon’s status and the implementation and 

effectiveness of protective measures. 

Species Biology 

Atlantic sturgeon is an anadromous species, meaning that it migrates from the ocean and returns 

to fresh water to spawn. It may live up to 60 years, reach lengths up to 14 feet (4.3 meters), and 

weigh over 800 pounds. There is no defined age at which this species reaches maturity because it 

appears to correspond with the temperature of the water in which it lives. In colder waters, males 

reach maturity at about 20 years old, and females at around 25 years old. In warmer waters, 

males reach maturity at about 9 years old, and females about 12 years old. Spawning occurs in 

large rivers where the salt and fresh waters meet and where the first natural falls (fall line) occur. 

Approximately 12-14 days after the eggs are deposited, larvae begin their bottom dwelling lives. 

Larvae then migrate downstream and will remain in estuarine waters for months or a few years. 

Then the juveniles as well as subadults may migrate long distances and enter other river systems 

to feed. Since Atlantic sturgeon is a species that matures late, there are more opportunities for 

individuals to die before reaching sexual maturity. However, Atlantic sturgeon has a long life 

span that will provide mature individuals many opportunities to breed. 

Distribution and Abundance 

Atlantic sturgeon have been found along the entire Atlantic coast in North America from 

Hamilton Inlet in Labrador, Canada to the St. Johns River, Florida. In the United States alone, 

Atlantic sturgeon were present in 34 rivers from Maine to Florida. Currently, they can be found 

in 32 rivers from Maine to Georgia with spawning occurring in at least 14 of these rivers. During 

the 1800's, populations declined due to heavy fishing pressure, and presently all sturgeon 

fisheries are closed and will remain so for decades. During the early to mid 1900's, major 

industrialization caused degradation of sturgeon habitats, which have improved during the last 

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thirty years. Harvest in more recent years reduced abundance in most systems and caused a few 

known stocks to die off (Connecticut River, St. Marys River, GA/FL, and possibly the St. Johns 

River, FL). Atlantic sturgeon populations continued to survive despite these threats to the 

sturgeon and its habitat. 

Information on current or even historic abundance of Atlantic sturgeon is lacking for most river 

systems. The most recent information is available for the Delaware and Hudson Rivers where 

sturgeon fisheries occurred until 1996. The data showed that high rates of commercial fishing 

resulted in decreased abundance. In some southern areas where the fishery had been closed for 

some time, data suggested that those stocks were rebuilding. With scientists collecting more 

data, organizations (federal, state, and private) improving sturgeon habitat, and the commercial 

fishery closed, Atlantic sturgeon populations should maintain or increase in abundance. 

Major Threats and Impacts 

The original and most significant threat to Atlantic sturgeon was commercial fishing. Since the 

1800's, sturgeon have been sought after for their eggs (caviar) and flesh (smoked). Records show 

that sturgeon were fished for in every major river along the Atlantic coast. Currently, there is no 

legal commercial fishery for Atlantic sturgeon, and retention of sturgeon caught as bycatch is 

prohibited. 

Atlantic sturgeon stocks may have been further impacted through habitat degradation, especially 

in the early to mid 1900's. However, the species persisted in many rivers, and populations 

rebounded to the point where commercial fisheries occurred in many rivers until 1996. Habitat 

degradation includes dams, river dredging, and degraded water quality. Analysis shows that 

dams do not significantly limit access of spawning habitat since most dams are built on the fall 

line. The potential for dredging impact, (destruction of spawning or feeding habitats and 

disruption of spawning migrations) has been found to occur in only six rivers with spawning 

populations, with no dredging occurring during the past 20 to 25 years on 21 sturgeon rivers. 

While sturgeon are sensitive to a variety of water quality problems, including changes in 

temperature, decreases in dissolved oxygen, additions of nutrients, and the presence of 

contaminants, available evidence shows that overall water quality in Atlantic sturgeon habitats is 

substantially better than it was through the 1970's and is continuing to improve, especially in the 

Northeast and Mid-Atlantic states. 

Conservation Programs 

Apart from the National Marine Fisheries Service and the U.S. Fish and Wildlife Service, many 

of the programs set up for conservation of the Atlantic sturgeon are created by the Atlantic States 

Marine Fisheries Commission’s Amendment 1 to the Atlantic sturgeon Fishery Management 

Plan, including measures for preservation of existing habitat, habitat restoration and 

improvement, monitoring of bycatch and stock recovery, and breeding/stocking protocols. Other 

organizations involved with Atlantic sturgeon conservation include, but are not limited to, State 

and local governments, private and conservation organizations . 

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Saltmarsh Topminnow: 

Fundulus jenkinsi 

NMFS designated the saltmarsh 

topminnow as a candidate species in 

1997. In 1998 NMFS initiated a status survey on this species to determine if listing under the 

ESA is warranted. Data on this species are minimal because large samples are hard to find. 

Most of the data available on this species is more than ten years old, so current status is very 

difficult to determine. 

Species Biology 

The saltmarsh topminnow is one of the smallest members of the topminnow/killifish family 

Fundulidae, genus Fundulus, seldom exceeding 40-45 mm, with most individuals in scientific 

collections ranging from 25 to 35 mm. Although the life history of this species is poorly known, 

previous study suggests that this species may be close to an annual species, with few adults 

surviving past the breeding season in their second year of life. Research has shown the breeding 

season of this species to be from April through August. This short life span makes this species 

particularly vulnerable to drastic population level fluctuations from climate variability and 

environmental variations in available habitat. This species requires shallow flooded marsh 

surfaces for breeding and feeding, and coastal erosion and man-made conversions of marsh 

habitat to other uses is thought to be the greatest threat to the continued existence of this species. 

Construction of new habitat for this species could be part of a management solution for 

enhancing this species’ population stability. Coastal restoration construction projects are being 

implemented to reverse habitat alteration and destructive loss of marsh along the coast of the 

Gulf of Mexico, particularly in Louisiana. 

Distribution and Abundance 

The species is endemic to the north-central coast of the Gulf of Mexico of southern United 

States, from Galveston Bay, Texas, eastward through Louisiana, Mississippi, Alabama and parts 

of western Florida. It is believed that specimens can be found in the Perdido, Escambia, and East 

Bays of Florida. They tend to live in salt marshes and brackish water, although it has been found 

that they can survive in freshwater. F. jenkinsi can also be found in shallow tidal meanders of 

Spartina marshes. 

Major Threats and Impacts 

Habitat alteration is the most serious threat to the saltmarsh topminnow. In areas associated with 

the Lower Mississippi River delta system, land loss from coastal erosion is rapidly destroying the 

marsh surface that is part of the necessary habitat of this species. Conversion of marsh to deeper, 

open water eliminates the marsh surface that, when flooded, provides important feeding, shelter, 

and possible breeding areas for saltmarsh topminnow. Erosion of marsh areas on several of 

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Louisiana’s barrier islands has completely eliminated several locations where this species has 

been collected in the past. Conversion of marsh surface associated with estuarine streams and 

meanders to non-flooded "fast-lands" also threatens this species. Disposal of dredged materials 

also will interrupt or destroy habitat in that flooding is reduced or eliminated, thus restricting its 

use by this species. 

Protection of marsh habitat is vital for the continued success of the saltmarsh topminnow along 

the Gulf Coast. Whether programs designed to restore coastal marsh will be successful in 

providing habitat for the saltmarsh topminnow has not been demonstrated yet. 

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White Abalone: Haliotes 

sorenseni 

The white abalone is currently the only 

mollusk currently on the NMFS candidate 

species list. It was added in 1997 for the 

California region south to Baja California, 

Mexico. A short lived commercial fishery 

began in the early 1970s, peaked mid-decade 

and collapsed in the 1980's. Only occasional 

landings occurred after that time. It was also 

sought after by recreational divers, but actual 

landings are unknown. Recent studies 

suggest that this species has likely suffered reproductive failure resulting from severe overharvest. The fishery was closed in 1996. In 1998, NMFS initiated a status review on this species 

to determine if listing under the ESA is warranted. 

Species Biology 

The white abalone is a herbivorous, marine, rocky benthic, broadcast spawning gastropod. The 

epipodium is tan and looks pebbly. The bottom of its foot is orange. The shell is oval-shaped, 

very thin and deep. They can be up to 10 inches, but are usually 5-8 inches. If fertilized, the 

eggs hatch after only one day, but high concentrations of sperm are required in order for an egg to 

be fertilized. Therefore, aggregations of adults are necessary for successful fertilization to occur. 

Distribution & Abundance 

The white abalone dwells in deep waters - 80 to over 200 feet from Point Conception (southern 

California) southward to Baja California. Because of its depth range, this abalone was only 

described scientifically in 1940. It lives on rocky substratum such as pinnacles, rock piles, and 

deep reefs. Once occurring in numbers as high as 1 per square meter of suitable habitat, they 

now can be found only occasionally. Recent surveys found that densities average 1 per hectare in 

the Channel Islands of southern California. 

Major Threats and Impacts 

Currently, the white abalone are frequently found alone, and have little chance for successful 

fertilization. Because populations are only small fractions of former numbers, recovery will be 

complicated by loss of genetic diversity from genetic bottlenecks, genetic drift and founder 

effects. Abalones are also vulnerable to various bacterial and parasitic infections. The fishery 

was historically managed using size limits and seasons, but such methods failed because they did 

not account for density dependent reproduction and assumed regular successful settlement of the 

larvae. 

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Conservation Programs 

There are numerous groups, both in the United States and internationally, doing work to gather 

more information and build programs to help save the white abalone. Some of these active 

groups include the Channel Islands National Park Service and the California Department of Fish 

and Game. These groups assess abalone populations and conduct research into the basic biology, 

disease pathology and ecology of abalones. 

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