Recovery Plan for U.S. Pacific Populations

of the

U.S. Department of Commerce

National Oceanic and Atmospheric Administration

National Marine Fisheries Service

U.S. Department of the Interior

U.S. Fish and Wildlife Service

East Pacific GreenTurtle

(Chelonia mydas)
Cover Photograph Courtesy of Kim Cliffton

RECOVERY PLAN FOR U.S. PACIFIC POPULATIONS OF THE 
RECOVERY PLAN FOR U.S. PACIFIC POPULATIONS OF THE 

EAST PACIFIC GREEN TURTLE 

(Chelonia mydas) 

Prepared by the 

Pacific Sea Turtle Recovery Team 

for 

National Marine Fisheries Service 

Silver Spring, Maryland 

and 

Pacific Region 

U.S. Fish and Wildlife Service 

Portland, Oregon 

Approved: 

Date: /Je23-f? 

~~~~~"~&Asr>t?d!!6i~~heries. National Marine Fisheries Service 

Date: 
Recovery plans delineate reasonable actions which are believed to be required to recover

and/or protect the species. Plans are prepared by the National Marine Fisheries Service

(NMFS) and the U.S. Fish and Wildlife Service (FWS), and sometimes with the assistance of

recovery teams, contractors, State agencies and others. Objectives will only be attained and

funds expended contingently upon appropriations, priorities and other budgetary constraints. 

Recovery plans do not necessarily represent the views nor the official positions or approvals of

any individuals or agencies, other than those of NMFS and the FWS which were involved in

the plan formulation. They represent the official positions of NMFS and the FWS only after

they have been approved by the Assistant Administrator for Fisheries or the Regional Director. 

Approved recovery plans are subject to modification as dictated by new findings, changes in

species status and the completion of recovery tasks.

Literature citations should read as follows:

National Marine Fisheries Service and U.S. Fish and Wildlife Service. 1998. Recovery Plan

for U.S. Pacific Populations of the East Pacific Green Turtle (Chelonia mydas). 

National Marine Fisheries Service, Silver Spring, MD.

Additional copies of this plan may be purchased from:

Fish and Wildlife Reference Service

5430 Grosvenor Lane

Suite 110

Bethesda, Maryland 20814

(301)492-6403 or 

1-800-582-3421

The fee for the plan varies depending on the number of pages of the plan.
i

TABLE OF CONTENTS

(East Pacific Green)

PREFACE ................................................................... iii

ACKNOWLEDGMENTS ........................................................ iv

LIST OF ABBREVIATIONS ...................................................... v

EXECUTIVE SUMMARY ....................................................... vi

I. INTRODUCTION ............................................................ 1

A. Geographic Scope ..................................................... 1

B. Historical and Cultural Background ........................................ 4

C. Taxonomy ........................................................... 5

D. Description .......................................................... 6

E. Population Distribution and Size .......................................... 6

Nesting Grounds ................................................... 6

Insular and Pelagic Range ........................................... 7

F. Status .............................................................. 8

G. Biological Characteristics ............................................... 9

Migration and Movements ............................................ 9

Foraging Biology and Diet ........................................... 10

Growth .......................................................... 10

Reproduction ..................................................... 11

Offshore Behavior ................................................. 12

Health Status ..................................................... 12

H. Threats ............................................................ 12

Pacific Synopsis .................................................. 13

Regional Summaries ............................................... 13

U.S. West Coast ............................................ 13

Other U.S. Areas ............................................ 13

General Threat Information .......................................... 15

Nesting Environment ......................................... 15

 1. Directed Take ...................................... 15

 2. Increased Human Presence ........................... 15

 3. Coastal Construction ................................. 15

 4. Nest Predation ...................................... 15

 5. Beach Erosion ...................................... 16

 6. Artificial Lighting .................................... 16

 7. Beach Mining ....................................... 16

 8. Vehicular Driving on Beaches .......................... 16

 9. Exotic Vegetation ................................... 16

10. Beach Cleaning .................................... 17

11. Beach Replenishment ............................... 17

Marine Environment .......................................... 17

12. Directed Take ...................................... 17

13. Natural Disasters ................................... 17
ii

14. Disease and Parasites .............................. 17

15. Algae, Seagrass and Reef Degradation ................. 18

16. Environmental Contaminants ......................... 18

17. Debris (Entanglement and Ingestion) ................... 18

18. Fisheries (Incidental Take) ........................... 18

19. Predation ......................................... 19

20. Boat Collisions ..................................... 19

21. Marina and Dock Development ........................ 19

22. Dredging ......................................... 19

23. Dynamite “Fishing” ................................. 20

24. Oil Exploration and Development ...................... 20

25. Power Plant Entrapment ............................. 20

26. Construction Blasting ............................... 20

I. Conservation Accomplishments .......................................... 21

Nesting Environment ............................................... 21

Marine Environment ............................................... 21

II. RECOVERY ............................................................... 22

A. Recovery Objectives ................................................... 22

B. Step Down Outline and Narrative for Recovery .............................. 23

III. REFERENCES CITED ...................................................... 35

IV. IMPLEMENTATION SCHEDULE .............................................. 40
iii

PREFACE

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

share responsibilities at the Federal level for the research, management, and recovery of Pacific

marine turtle populations under U.S. jurisdiction. To accomplish the drafting of this recovery plan,

NMFS appointed a team of professional biologists experienced with marine turtles in the Pacific

region. This document is one of six recovery plans (one for each of the five species plus one for

the regionally important population of the East Pacific green turtle). 

While similar in format to previously drafted sea turtle recovery plans for the Atlantic,

Caribbean, and Hawaii, the unique nature of the wider Pacific region required some modification

of the recovery plan format. The geographic scope of the present plan is much larger than any

previously attempted and considers areas from the western coastal United States extending to

Guam. Furthermore, the amount of jurisdictional overlap between nations, commonwealths,

territories and compact-of-free-association-states and their various turtle populations required a

broader management perspective than has been attempted previously. Finally, sea turtles have

not been studied as comprehensively in the Pacific as in other U.S. areas, and thus there are

many areas in the Pacific where basic biological and ecological information must be obtained for

management purposes. Thus, these plans have more extensive text on the general biology of the

turtles, so that they might act as a resource to managers seeking a handy reference to the

species. The plans are also subdivided into U.S. jurisdictional areas (i.e., the various territories

and the commonwealth), so that local managers can address issues within their respective regions

more easily. 

Because of the previously noted aspects of marine turtle distribution in the Pacific (e.g., wide

geographic range, multiple jurisdictions), the Recovery Team relied on the input and involvement

of a large number of advisers, as can be noted by the lengthy Acknowledgments section. It is

hoped that the resulting document is one that acts as a pragmatic guide to recovering the

threatened and endangered sea turtle populations in the Pacific Ocean.

The members of the Pacific Sea Turtle Recovery Team and the authors of this document are:

Scott A. Eckert, Ph.D. (Team Leader)

Hubbs-Sea World Research Institute

Javier Alvarado, Ph.D.

Universidad de Michoacan, Mexico

George Balazs

National Marine Fisheries Service

Richard Byles, Ph.D.

U.S. Fish and Wildlife Service

Peter Craig, Ph.D.

Office of Wildlife and Marine Resources,

Government of American Samoa

Peter Dutton, Ph.D.

Texas A&M University

Karen Eckert, Ph.D.

Wider Caribbean Sea Turtle Conservation

Network (WIDECAST)

John Engbring

 U.S. Fish and Wildlife Service

James Maragos, Ph.D.

East-West Center

Robert Pitman

National Marine Fisheries Service

Susan Pultz

U.S. Fish and Wildlife Service

James I. Richardson, Ph.D.

University of Georgia
iv

ACKNOWLEDGMENTS

The team wishes to thank and acknowledge the following technical advisors and contributors to

these recovery plans:

David Aldan, Department of Natural Resources, Saipan, MP 

Pablo Arenas, Inter-American Tropical Tuna Commission

Representative Mariano W. Carlos, Palau 

Chuck Cook, The Nature Conservancy

Donald David, FSM

Gerry Davis, Division of Aquatic and Wildlife Resources, Dept. Agriculture, Guam

Oscar DeBrum, former Chief Secretary, RMI

Adrienne Farago, SPREP/RMTCP, Western Samoa

Michael Guilbeaux, Georgia Sea Turtle Cooperative

Vincent Hachiglou, Marine Resources Management Division, Yap State Government

Heidi Hirsh, Andersen Air Force Base, Guam

Paul Holthus, IUCN Biodiversity Program

Luciana Honigman, The Nature Conservancy

Noah Idechong, Division of Marine Resources, Palau

John Iou, Marine Resources Management Division, Yap State Government

Bruce Jensen, Pacific Magazine

Harry Kami, Hilo, Hawaii

Angela Kay Kepler, Athens, Georgia

Steve Kolinski, Marine Resources Management Division, Yap State Government

Colin Limpus, Queensland National Parks and Wildlife Service, Australia

Becky Madraisau, Micronesian Mariculture Demonstration Center, Republic of Palau

B. Renè Màrquez-M., P.N.I.T.M./INP, Mexico 

Donna McDonald, Ocean Planet Research

Ken McDermond, U.S. Fish and Wildlife Service, Honolulu

Jeffery Miller, Queensland Department of Environment & Heritage, Australia

Susan Miller, South Pacific Regional Environment Program (SPREP)

Karen Miller McClune, Hubbs-Sea World Research Institute

Moses Nelson, Marine Resources Division, FSM

Peter Oliver, RMI

Arnold Palacios, Division of Fish and Wildlife, Dept. of Natural Resources, CNMI

Peter Pritchard, Florida Audubon Society

Georgita Ruiz, Colonia Irrigacion, Mexico

Laura Sarti, Universidad Naçional Autonoma de Mexico, Mexico

Fumihiko Sato, Ogasawara Marine Center, Japan

Katsufumi Sato, Kyoto University, Japan

Asterio Takesy, Secretary of Resources and Development, FSM

Natasha Tuato’o-Bartley, Department of Marine and Wildlife Resources, American Samoa

Itaru Uchida, Port of Nagoya Public Aquarium, Japan 

Richard Wass, U.S. Fish and Wildlife Service

Phil Williams, National Marine Fisheries Service
v

LIST OF ABBREVIATIONS

CCL curved carapace length

CITES Convention on International Trade in Endangered Species of Wild Fauna

and Flora

CNMI Commonwealth of the Northern Mariana Islands

COE U.S. Army Corps of Engineers

DAWR Division of Aquatic and Wildlife Resources

EEZ Exclusive Economic Zone

ENSO El Niño - Southern Oscillation

EPA U.S. Environmental Protection Agency 

ESA Endangered Species Act

ETP Eastern Tropical Pacific

FENA females estimated to nest annually 

FSM Federated States of Micronesia

FWS U.S. Fish and Wildlife Service

HSWRI Hubbs-Sea World Research Institute

IATTC Inter-American Tropical Tuna Commission

INP Instituto Nacional de Pesca

IUCN International Union for the Conservation of Nature

MHI Main Hawaiian Islands

MIMRA Marshall Islands Marine Resource Authority

MMDC Micronesian Mariculture Demonstration Center

MRMD Marine Resources Management Division, Yap State government 

mtDNA mitochondrial DNA

NMFS National Marine Fisheries Service

NOAA National Oceanographic and Atmospheric Administration 

NPS National Park Service

NRCS Natural Resources Conservation Service (Soil Conservation Service)

NWHI Northwest Hawaiian Islands

PNG Papua New Guinea

RMI Republic of the Marshall Islands

SCL straight carapace length

SDG&E San Diego Gas & Electric 

SPREP South Pacific Regional Environment Program

TAMU Texas A & M University

TED Turtle Excluder Device 

UNAM Universidad Naçional Autonoma de Mexico

USCG U.S. Coast Guard

USVI U.S. Virgin Islands

WIDECAST Wider Caribbean Sea Turtle Conservation Network
vi

EXECUTIVE SUMMARY 

Current 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 undoubtably 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 early 1980 on mainland beaches of Mexico. Primary

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

threats in Mexico are the (illegal) harvest of turtles and eggs.

Goal: The recovery goal is to delist this regionally important population.

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. 

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. 

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

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.
1

 RECOVERY PLAN FOR U.S. PACIFIC POPULATIONS OF THE

EAST PACIFIC GREEN TURTLE (Chelonia mydas)

Prepared by the 

U.S. Pacific Sea Turtle Recovery Team

I. INTRODUCTION

A. Geographic Scope

Defining the geographic range of a population of sea turtles in the Pacific Ocean is difficult.

Sea turtles are highly migratory, and the life histories of all species exhibit complex movements

and migrations through geographically disparate habitats. Because the U.S. Pacific Sea Turtle

Recovery Team is required to focus on sea turtle populations that reside within U.S. jurisdiction,

we must delineate what constitutes a population where individuals reside permanently or

temporarily within U.S. jurisdiction and what actions must be taken to restore that population. This

has proven to be quite challenging because sea turtles do not recognize arbitrary national

boundaries and in most cases we have only limited data on stock ranges and movements of the

various populations. In this recovery plan we have tried to make these judgements with the best

information available, and to suggest means by which the United States can promote population

recovery. 

Geographic scope (from a U.S. jurisdictional perspective) for all six of the U.S. Pacific sea

turtle recovery plans (written for five species and one regionally important population) is defined

as follows: in the eastern Pacific, the west coast of the continental United States (Figure 1a); in

the central Pacific, the state of Hawaii and the unincorporated U.S. territories of Howland, Baker,

Wake, Jarvis, and Midway Islands, Johnston Atoll, Palmyra Atoll, and Kingman Reef; in Oceania,

Guam, the Commonwealth of the Northern Mariana Islands (CNMI), and American Samoa (see

Figure 1b). The U.S.-affiliated but independent nations of the Republic of the Marshall Islands

(RMI), Federated States of Micronesia (FSM), and the Republic of Palau are also included. The

FSM includes the states of Yap, Pohnpei, Chuuk, and Kosrae. While independent, all retain

clearly defined administrative links to the United States in the areas of defense, natural resource

management, and some regulatory issues. Thus, we include them here in an advisory capacity.

Finally, where eastern Pacific sea turtles are held in common with Mexico, discussion of the status

and recovery of these stocks will also include discussion of the resource under Mexican

jurisdiction. In all cases where U.S. sea turtle stocks are held in common with other sovereign

states, we have tried to suggest means by which the United States can support efforts at

management of those stocks by those states. We recognize that other nations may have different

priorities than the United States and we have sincerely attempted to avoid establishing policy for

those nations.

Because of the highly migratory behavior of adult turtles, and the likelihood of shifting habitat

requirements of post-hatchlings and juveniles, the populations of East Pacific green turtles,

Chelonia mydas, in the Pacific Ocean cross international boundaries. 
Figure 1 a. Western coasts of the United States, Canada and Mexico (as well as Central and 

northern South America) constitute a shared habitat for Pacific sea turtles. 
Figure I b. The western Pacific constitutes a shared habitat for Pacific sea turtles. 

3 
4

The west coasts of Central America, Mexico and the United States constitute a shared habitat for

East Pacific green turtles. The following discussions acknowledge the extended range of East

Pacific green turtles by incorporating relevant biological information from within and without U.S.

political jurisdiction.

B. Historical and Cultural Background

Prior to commercial exploitation, the East Pacific green turtle was abundant in the eastern

Pacific from Baja California south to Peru and west to the Galapagos Islands. Historically the

species was plentiful in the feeding grounds within the Gulf of California (Sea of Cortez) and along

the Pacific coast of Baja California (Cliffton et al. 1982). An indication of its former numbers is

found in the report of the visit of the vessel Albatross to Tortugas Bay on the Pacific coast of Baja

California (Mexico) in April 1889, when a catch of 162 turtles was made in a single haul by a 200

m seine (Parsons 1962). As late as the 1960s the East Pacific green turtle was still abundant in

its major nesting grounds in North America; that is the beaches of Colola and Maruata Bay,

Michoacán, Mexico. It is estimated that in the late 1960s, 500 - 1,000 females nested nightly in

Colola during peak season. Cliffton et al. (1982) extrapolated that perhaps 25,000 females nested

annually in Michoacán at that time. Earlier observations tend to corroborate this figure; Peters

(1956) reported tracks of some 250 turtles on a 0.8 km stretch of beach at Maruata Bay in August

1950, two months before peak nesting. Cliffton et al. (1982) estimated that approximately 900

turtles must have nested at Maruata Bay within several days of Peters' observations.

The East Pacific green turtle has been used by coastal indigenous communities throughout

its range since pre-Columbian times. The Seri Indians of the Sonora coast in Mexico harvested

East Pacific green turtles in the Gulf of California, and turtle meat represented the main

component in their diet at least until the end of the 1800s (Caldwell 1963). The Seri also utilized

turtle shells for housing material, and flipper integument was employed as footwear. In Oaxaca,

Mexico, the Huave Indians traditionally consumed the meat of East Pacific green turtle adults and

juveniles (Márquez 1990). For the Nahuatl Indians of the Michoacán coast East Pacific green

turtle eggs were an important dietary staple (Alvarado and Figueroa 1991a). However, with the

introduction of commercial demand for sea turtle products, the centuries old, low-impact, traditional

subsistence use of the East Pacific green turtle was replaced by a rapidly expanding commercial

fishery.

In the northern Mexican feeding grounds East Pacific green turtles were first heavily fished at

the turn of the century, when an estimated 1,000 East Pacific green turtles per month were

shipped from the Pacific side of Baja California (Magdalena Bay, Scammon's Lagoon, Tortugas

Bay) and Gulf of California (Bahia de los Angeles) to San Diego and San Francisco in California,

United States (O'Donnell 1974 in Cliffton et al. 1982). By the 1930's, the market for sea turtle

meat had decreased in the United States, while in Mexico - especially in the border towns of

Tijuana, Mexicali and Nogales, and the major cities in Baja California and Sonora - the demand

for turtle meat grew steadily. From 1956 to 1963, East Pacific green turtles harvested in the

northern Mexican feeding grounds were the most important component of the Mexican turtle

fishery, with a total live weight production of 3,430 metric tons (Groombridge and Luxmoore 1989).

In the early 1970s large numbers of overwintering East Pacific green turtles were discovered near

Tiburon Island in the Gulf of California. The torpid turtles were lying motionless at depths of

10-30m (Felger et al. 1976). Intensive hunting of the easily caught overwintering turtles began in

1975, when five boats were landing 4-5 metric tons of turtles per week from late November to
5

early March (Cliffton et al. 1982). Overwintering sites were successively decimated and the East

Pacific green turtle was "virtually extirpated" from the Gulf of California by the late 1970s (Cliffton

et al. 1982). According to Cliffton (in litt. to J. Woody, 5 May 1991) who conducted a 30-day

exploration of the Midriff Islands region in the summer of 1990, adult East Pacific green turtles

were extremely scarce. Cliffton quotes native informants as stating that most of the East Pacific

green turtles remaining in the Upper Gulf of California are juveniles weighing an average of about

20 kg.

Commercial exploitation of East Pacific green turtles in the nesting area in Michoacán was

initiated considerably later than in the northern feeding grounds. Prior to the 1950s the coastal

breeding sites were relatively undisturbed as the coastline was virtually uninhabited and

inaccessible. During the 1950s coastal areas were increasingly cleared and the coastal

settlements of Maruata and Colola were established. Access to the area remained difficult by land

and, at that time, use of turtles by the local Nahuatl Indians was at a subsistence level. During the

1960s commercial markets for sea turtle products, including both leather and eggs, were

developed. In the early 1970s approximately 70,000 eggs were collected each night during the

breeding season at Colola and an additional 10,000 - 20,000 from Maruata Bay (Cliffton et al.

1982). This nearly 100% harvest of eggs continued until 1980 when armed protection of Colola

and Maruata was begun and hatcheries for the relocation of nests were established (Alvarado et

al. 1985).

Sea turtle leather processing in Mexico had been on a local, artisanal level up until the end of

1963 (Groombridge and Luxmoore 1989). During 1964, with the increase in international demand

for the product, larger scale, industrial processing began (Alvarado and Figueroa 1989). From the

mid-1960s to mid-1970s East Pacific green turtles in Michoacán were harvested mainly for their

skins. During the mid-1970s breeding seasons, local fishermen were capturing 40 - 80 turtles per

day in Maruata, or about 7,000 - 15,000 turtles per season. Turtles were captured with shark

gillnets in front of the nesting beaches and stripped of their hides (Cliffton et al. 1982). From 1965

to 1977 more than 165,000 East Pacific green turtles were harvested in the Mexican Pacific

(Groombridge and Luxmoore 1989). In 1978 a new coastal highway reached the area, providing

smugglers from the northern states of Sinaloa and Sonora easy access to the Michoacán turtles.

Since then most poached turtles from this area have been smuggled to northern Mexico for meat

consumption (Alvarado and Figueroa 1990). This fishery has been by far the most important

factor in the collapse of East Pacific green turtle populations.

There are no accurate quantitative records of historical abundance of East Pacific green turtles

in the Galapagos Islands, the only significant nesting area outside of Mexico. Only local

inhabitants are legally allowed to fish for turtles and only on a subsistence basis; egg poaching

is practically nonexistent (Green and Ortiz-Crespo 1982).

C. Taxonomy

The generic name Chelonia was introduced by Brongniart (1800). The specific name mydas

was first used by Linnaeus (1758). The genus Chelonia is often considered to include the single

species C. mydas with two distinct subspecies recognized: the East Pacific green turtle C. m.

agassizii (Bocourt 1868) in the eastern Pacific (from Baja California south to Peru and west to the

Galapagos Islands) and the green turtle C. m. mydas (Linnaeus 1758) in the rest of the global
6

range (Groombridge and Luxmoore 1989). Nevertheless, there has been some controversy over

the taxonomic status of the East Pacific green turtle. The nesting populations of the east Pacific

differ from other forms of mydas in size, coloration, carapace shape (Cornelius 1986; Groombridge

and Luxmoore 1989), as well as in osteological features (Kamezaki and Matsui 1995). Nuclear

DNA analysis of Chelonia populations showed that samples from the Pacific coast of Mexico and

the Galapagos Islands were closely associated and fairly remote from other populations (Karl et

al. 1992), however, mitochondrial DNA (mtDNA) analyses of the global C. mydas complex do not

support the genetic distinctness of the East Pacific green turtle from Chelonia populations in other

regions of the world (Bowen et al. 1992; Dutton et al. 1996). It is clear that the question of species

status must ultimately be resolved by taking into account morphometric, genetic and behavioral

aspects. In the absence of a thorough study of the morphology and genetics of the agassizii form,

set in the context of the overall systematics of the C. mydas group, the East Pacific green turtle

is considered to be a melanistic form of Chelonia mydas of the monotypic genus Chelonia for the

purpose of this recovery plan.

Regardless of taxonomic designation ultimately conferred upon the melanistic form, the

remaining large nesting populations of Chelonia in the east Pacific should be managed as distinct

population units. This document presents an agenda for the recovery of these regionally distinct

and important populations. 

D. Description

The East Pacific green turtle is distinguished from the green turtle mainly by size, coloration

and carapace shape. The carapace of the adult East Pacific green turtle is narrower, more

strongly vaulted and more indented over the rear flippers than that of the green turtle (Cornelius

1986; Márquez 1990). The East Pacific green turtle is also conspicuously smaller and lighter than

the green turtle. In the rookeries of Michoacán, Mexico, the mean size for nesting females is 82.0

cm in curved carapace length (CCL) (range 60.0-102, n=718) (Alvarado and Figueroa 1990). On

the Galapagos Islands, the mean CCL for nesting females is 80.0 cm (range 74.0-100) (Márquez

1990). The mean straight carapace length (SCL) of nesting females at Playa Naranjo, Costa Rica

is 82.9 cm (range 73.0-97.0, n=73) (Cornelius 1976). Adult females weigh between 65 - 125 kgs

(Cornelius 1986). Adult males in the rookeries of Mexico are smaller than females with an average

CCL of 77.0 cm (range 71.0-85.0, n=32) (Figueroa 1989). Mean hatchling length in Michoacán

is 4.5 cm in SCL (range 4.2-5.0, n=140) (Zamora 1990).

In adult East Pacific green turtles, the carapace and dorsal surfaces of the head and flippers

are olive-green to dark gray or black, while the plastron varies from whitish-grey to bluish or

olive-grey. Considerable gray pigment often infuses the plastron. Hatchlings are black to dark

grey above and white below with a white border around the dorsal edge of the carapace and

flippers. Young juveniles are usually brightly colored with a mottled or radiating carapacial pattern

of light and dark brown, reddish brown, olive and yellow (Caldwell 1962).
7

E. Population Distribution and Size

Nesting Grounds

There is no known nesting by this species in the United States or in any territory under U.S.

jurisdiction. The main nesting sites for the East Pacific green turtle are located in the state of

Michoacán, Mexico (Colola and Maruata beaches) and in the Galapagos Islands, Ecuador. The

Michoacán rookeries support about one third of the East Pacific green turtle population (Cliffton

et al. 1982). There are also less important nesting grounds in Mexico (Guerrero, Jalisco, Oaxaca,

Chiapas, the islands of Clarion and Socorro) (Márquez 1990) and along the Central American

Pacific coastline (Cornelius 1982). Between 1982 and 1989 the estimated East Pacific green

turtle nesting population in Michoacán (Mexico) ranged from a high of 5,585 females in 1982 to

a low of 940 in 1984 (Alvarado and Figueroa 1990). In October 1976 at least 13 females visited

Clarion Island in the Revillagigedo archipelago in Mexico (Awbrey et al. 1984). 

At Playa Naranjo, Costa Rica, Cornelius (1976) tagged 80 nesting East Pacific green turtles

during 11 September 1971 - 31 March 1972 and estimated the population of nesting females to

be between 125 and 175. In the Galapagos Islands an annual average of 1,400 nesting East

Pacific green female turtles was registered between 1976 - 1982 (Hurtado 1984). Green (1994)

reported that between 1975 and 1980, a total of 6,722 green turtles (including 611 males) was

tagged at the nesting beaches and feeding grounds of the Galapagos Islands. There is scant

information on numbers of nesting females at other nesting sites. 

Insular and Pelagic Range

The East Pacific green is the second-most sighted turtle in the east Pacific during tuna fishing

cruises; they are frequent along a North-South band from 15EN to 5ES along 90EW, and between

the Galapagos Islands and Central American coast (Inter-American Tropical Tuna Commission,

IATTC, unpubl. data). Along the Pacific coast of America, East Pacific green turtles have been

reported as far north as British Columbia (48.15EN) (Carl 1955 in Márquez 1990). Loshbaugh

(1993) reported a "green turtle" stranding in Homer, Alaska, although it was not known whether

the turtle originated from the nesting beaches of Mexico or Hawaii. Adult and juvenile green/East

Pacific green turtles have also been reported either from gillnets or from beach strandings as far

north as 47E latitude along the Washington coastline (Eckert 1993). 

Stinson (1984) reviewed sea turtle sighting records from northern Baja California to Alaska and

determined that the East Pacific green turtle was the most commonly observed hard-shelled sea

turtle on the U.S. Pacific coast. Most of the sightings (62.0%) were reported from northern Baja

California and southern California. The northernmost reported resident population of East Pacific

green turtles occurs in San Diego Bay, California, where a small population (about 30) of mature

and immature turtles concentrate in the warm water effluent discharged by the San Diego Gas and

Electric Company power plant (Stinson 1984; Dutton and McDonald 1990a,b, 1992; McDonald et

al. 1995). Based on morphology and preliminary genetic analysis, these turtles appear to have

originated from nesting beaches in the east Pacific (Dutton et al. 1994); there is no known sea

turtle nesting on the west coast of the United States.
8

Beyond sightings offshore of the western coast of the continental United States, there are no

reported encounters with East Pacific green turtles in Hawaii or any territories or pelagic waters

under U.S. jurisdiction (see Geographic Scope).

Sighting and stranding reports of "green" turtles along the west coast of the United States are

probably mostly of the East Pacific green. It is not known whether they regularly migrate from

breeding grounds in Mexico to specific areas along the North American coast, or whether these

turtles are vagrants that occasionally stray into more northern waters, perhaps moving with "El

Niño" currents. Recently (October 9, 1996), a live, cold-stunned East Pacific green turtle was

recovered from Prince William Sound, Alaska (S. Eckert, pers. comm.) 

South of the United States, East Pacific green turtles are widely distributed in the coastal

waters of Mexico and Central America (e.g., Cliffton et al. 1982; Cornelius 1982, 1986; Alvarado

and Figueroa 1990). Along the coast of Mexico and Central America the main aggregations of

East Pacific green turtles occur in the breeding grounds of Michoacán, Mexico (August-January)

and year-round in the feeding areas such as those located on the west coast of Baja California,

in the Gulf of California (Sea of Cortez) and along the coast of Oaxaca. Foraging is also reported

from Central America, especially in El Salvador (Márquez 1990). East Pacific green turtles are not

restricted to coastal waters, however. After nesting at Colola, Michoacán, on November 17, 1991

a satellite-tagged female traveled northwest and arrived at the Islas Tres Marias archipelago

(presumably to feed) within two weeks (R. Byles, U.S. Fish and Wildlife Service [FWS] pers.

comm., 1992). 

The IATTC reports that during tuna fishing cruises from Baja California to Ecuador and west

to almost 150EW, East Pacific greens are seen most frequently in this area; males, females, and

juveniles were seen in this area during all times of the year. The algal beds around the Islands

of Ferdinanda e Isabel in the Galapagos archipelago are an important feeding ground for the East

Pacific green turtles nesting in the Islands (Green and Ortiz-Crespo 1982). The southernmost site

reported of East Pacific green turtle distribution is from Desolation Island in Chile (Márquez 1990).

F. Status

Under the U.S. Endangered Species Act (ESA) of 1973, as amended, the breeding

populations of Chelonia mydas from the Pacific coast of Mexico are listed as Endangered.

Similarly, all populations of Chelonia mydas are classified as Endangered in the International

Union for Conservation of Nature and Natural Resources' (IUCN) Red Data Book, where taxa so

classified are considered to be "in danger of extinction and whose survival is unlikely if the causal

factors continue operating" (Groombridge 1982). Populations of Chelonia mydas are included in

Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and

Flora (CITES), a designation which bans trade in specimens or products except by special permit.

Such permits must show that the trade is not detrimental to the survival of the species and is not

for primarily commercial purposes (Lyster 1985).

Excessive exploitation of the East Pacific green turtle throughout its range has caused a

dramatic decline in numbers over the 1900s. In Michoacán, Mexico where about one third of all

East Pacific green turtles nest, the population has exhibited a clear decline in numbers over the

last 40 years. Similarly, East Pacific green turtles were abundant and widespread in northern
9

Mexico feeding grounds (Gulf of California) and along the Pacific coast of Baja California as late

as the 1960s. Today, East Pacific green turtles are rare in the Gulf of California and most appear

to be juveniles (see Historical and Cultural Background).

In Mexico, a presidential decree (May 1990) banned the harvest of all sea turtles and their

eggs, as well as trade in sea turtle products. This has drastically diminished (but not eliminated)

clandestine harvest and trade in sea turtle products. Field enforcement, however, remains

extremely difficult. Effective 30 September 1991, Mexico became the 111th Party to CITES.

Mexico ratified CITES with no reservations.

G. Biological Characteristics

Migration and Movements

The dispersal of East Pacific green turtle hatchlings from natal beaches has not been studied,

but it can be assumed to include passive transport by ocean currents over vast distances.

According to tag-recovery data (as summarized by Alvarado and Figueroa 1990), East Pacific

green turtle migrations occur between the northern and southern extremes of their range.

Recoveries of nesting females tagged on the beaches of Michoacán have been documented from

El Salvador, Guatemala, Nicaragua, Costa Rica and Colombia. Recoveries have also been

documented from Mexican waters, primarily from the Gulf of California and adjacent waters, and

from the coast of Oaxaca. Tag recoveries in Central America are most common from El Salvador

and Guatemala. In Mexico the frequency of recovery is highest in the Gulf of California and

adjacent waters. Of 37 documented recaptures during 1989-1990, 32 were incidental catches,

mainly by shrimp and fish trawlers. Most of the recoveries were restricted to coastal waters,

perhaps because most commercial fishing in the east Pacific occurs on the narrow continental

shelf. The average depth at 13 coastal capture sites was 24.3 ± 5.8 m (range 10.0 - 72.0 m). The

longest distance covered by an East Pacific green turtle prior to capture was 3,160 km (measured

in the direct line along the coast) by a turtle tagged in Michoacán and recovered at El Faro,

Charambira, Colombia in October 1986. Minimum average traveling speed is 22.5 km/day (range

8.0 - 38.0, n=7). A post-nesting female that was satellite-tagged at Colola in Michoacán in

October 1991 traveled to Central America and was tracked for two months; she swam about 2,000

km with a daily average distance of 33 km (Byles et al. 1995).

Tag-recovery data indicates that at least part of the East Pacific green turtle population

breeding in the Galapagos Islands is recruited from distant feeding grounds. Galapagos-tagged

turtles have been recovered in the coastal waters of Costa Rica, Panama, mainland Ecuador,

Colombia and Peru (Green 1984; MacFarland 1984). The Galapagos archipelago lies

approximately 1,000 km off the coast of mainland Ecuador; thus, movements between mainland

feeding and island breeding grounds involve crossing a vast expanse of open ocean. An

undetermined portion of the Galapagos breeding contingent remains in the feeding grounds

around the Galapagos Islands year-round (Green and Ortiz-Crespo 1982; MacFarland 1984).

Some East Pacific green turtles nesting in Costa Rica may also be year-around residents

(Cornelius 1986).

Data collected during tuna fishing cruises suggest that East Pacific green turtles are most

frequent along a North-South band from 15EN to 5ES along 90EW from January through March,
10

but most frequent between the Galapagos Islands and the Central American coast from July

through September (IATTC, unpubl. data). Green (1984) suggested earlier that this observed shift

might indicate migratory movement. IATTC data suggest that East Pacific greens are rare near

the Mexican coast, and are only present during October through December.

A small aggregation of turtles in San Diego Bay, tentatively identified as East Pacific greens,

seems to be year-round residents, and the fact that small (<55 cm SCL) juveniles are regularly

seen suggests that turtles are continuing to migrate into the bay (Stinson 1984; McDonald and

Dutton 1993; McDonald et al. 1995).

Foraging Biology and Diet

Although East Pacific green turtle feeding grounds are not clearly delimited, the main sites

appear to be the west coast of Baja California, Mexico (Scammon’s Lagoon, Tortugas Bay and

Magdalena Bay) (Cliffton et al. 1982), the Gulf of California (Felger et al. 1976; Márquez 1990),

the Superior and Inferior lagoons in Oaxaca, Mexico (R. Márquez, Instituto Nacional de Pesca,

INP, pers. comm., 1989), the Galapagos Islands (Green and Ortiz-Crespo 1982; MacFarland

1984), the Gulf of Fonseca (Honduras), and the Paracas Peninsula in Peru (Márquez 1990).

According to tag-recovery information, the feeding grounds of the Michoacán breeding population

are restricted to Mexico and Central America (Alvarado and Figueroa 1990), whereas the

population breeding in the Galapagos Islands forages from Costa Rica south to Peru (Green and

Ortiz-Crespo 1982; Green 1984; MacFarland 1984). It is not known where turtles traveling along

the west coast of the United States forage; turtles in San Diego Bay feed on eelgrass and algae

in the bay (Dutton and McDonald 1990a,b; McDonald et al. 1995).

Adult East Pacific green turtles are primarily herbivorous, eating sea grasses and algae, and

in some areas they may feed on a variety of marine animals. Food items vary among feeding

grounds. In Peru the following food items have been reported in stomach content analysis: plants

(Macrocystis, Rhodymenia and Gigartina), molluscs (Nassarius, Mytilus and Semele), polychaetes,

jellyfish, amphipods, and fish (sardine and anchovy) (Hays-Brown and Brown 1982). In the

Galapagos Islands the following items have been reported: algae (Caulerpa, Ulva) and mangrove

leaves (Rhizophora mangle) (Pritchard 1971). In Ecuador, Fritts (1981) reported fish eggs in the

stomach of a female turtle. In a sample of 19 turtles from Bahia de los Angeles, Gulf of California,

an average of 1,230 cm3 of food per individual was obtained, composed of 90.0% algae, 1.0%

animal food, and 9.0% unidentified material (Márquez 1990). The algae found in this study were:

Gracillaria, Rhodimenia, Gelidium, Grateloupia, Gigartina, Griffitsia, Sargassum,Padina, Ulva, and

Cladophora. Sargassum and Gracillaria were the most abundant. In the same study, animal food

items included small quantities of small molluscs, crustaceans, bryozoans, sponges, jellyfishes

and echinoderms. 

Casas-Andrew and Gomez-Aguirre (1980) report similar findings from off the central western

coast of Mexico, with Ulva being the most abundant algae in the samples. The stomach contents

of one turtle from this study consisted exclusively of the pelagic tunicate Pyrosoma. In the

Infiernillo Channel (area between Tiburon Island and the mainland) in the Gulf of California, East

Pacific green turtles feed on eelgrass, Zostera marina, and the sea slug, Aplesia californica

(Felger and Moser 1987). Feeding habits of hatchlings and juveniles are unknown.
11

Growth

In the Galapagos Islands, Green (1994) found a mean growth rate of 0.40 to 0.45 cm per year

for juveniles 40 - 60 cm SCL, while subadults (60.0 - 66.7 SCL) grew 0.15 cm per year. Growth

recorded for turtles in San Diego Bay was considerably faster. Growth rates for two individuals

(SCL 54.4 and 46.7 cm) were 6.7 and 5.1 cm/yr, respectively, while an 86.7 cm female grew 3.9

cm in one year (McDonald et al. 1995). Green (1994) reported that since the minimum size of

nesting turtles in the Galapagos Islands is 66.7 cm SCL, it may take some turtles at least 50 years

to reach sexual maturity. Based on growth rates observed in wild turtles, age at first reproduction

(minimum 81.0 cm SCL) for green turtles in the Hawaiian archipelago is estimated to be roughly

10-50 years depending on the feeding ground (Balazs 1982). 

Reproduction

Reproduction is seasonal. In most cases gravid females migrate long distances between

foraging and breeding grounds (see Migration and Movements). An exception may be the

Galapagos Islands, where large numbers of East Pacific green turtles were observed copulating

early in the year (IATTC, unpubl. data), and turtles are seen throughout the year. The nesting

season varies with location. Nesting occurs in Michoacán between August and January, with a

peak in October-November (Alvarado et al. 1985), between March and July at Socorro and Clarion

islands (Márquez 1990), between December and May with a peak in February-March on the

Galapagos Islands (Green and Ortiz-Crespo 1982), and possibly year-round with a peak in

October-March at Playa Naranjo, Costa Rica (Cornelius 1986). On beaches shared with other

nesting turtle species (e.g., Colola and Maruata in Michoacán) East Pacific green turtle nesting

occurs after the nesting peak of the olive ridley and before that of the leatherback (Alvarado et al.

1985). This may reduce competition for nesting space.

In Michoacán, females typically nest in two or three year cycles and deposit between one and

seven clutches per season at about 12-14 day intervals (Alvarado and Figueroa 1990). In the

Galapagos Islands, females typically nest in three or five year cycles and deposit between one

and five clutches per season at about 14 day intervals (Hurtado 1984). In Playa Naranjo, Costa

Rica, females may nest in consecutive years and deposit at least two and perhaps as many as

six nests per season at about 14 day intervals (Cornelius 1986).

Average clutch size varies geographically. In Michoacán, the average is 65 eggs (range

1-130, n=916 nests) (Alvarado and Figueroa 1990). In the Galapagos Islands, average clutch size

is 84 eggs (range 56-152, n=30 nests) (Hurtado 1984). In Playa Naranjo, Costa Rica, average

clutch size is 87 eggs (range 65-107, n=10 nests) (Cornelius 1976). After 42 to 62 days of

incubation (Márquez 1990) hatchlings emerge mostly at night and travel quickly to the sea. Nest

temperature during incubation influences the sex of hatchlings. At Michoacán, 47 East Pacific

green turtle clutches were monitored in 1984 and 1985 to determine the sex ratio of emergent

hatchlings. Average temperatures <27.0EC (range 26.4-27.0EC) during the mid-third of incubation

resulted in 100% males; average temperatures between 27.5-31.0EC resulted in a mixed sex ratio,

and those >31.0EC (range 31.0-32.9EC) produced 100% females (Alvarado and Figueroa 1987).

In most studied populations of sea turtles (all species), mating does not appear to occur once

nesting has commenced. This is true for Chelonia mydas in Australia (Booth and Peters 1972)

and Hawaii (Balazs 1980). In contrast, East Pacific green turtle mating apparently can occur both
12

prior to and between nestings at the Michoacán rookery, and sequential mating throughout the

season is implied (Alvarado and Figueroa 1991b).

Offshore Behavior

During observations from tuna fishing cruises, East Pacific green turtles are often seen

basking at the surface. Turtles seem to be most active around midday; 30% of the green turtles

seen swimming were seen around noon (IATTC, unpubl. data). They were almost always seen

near islands, feeding very close to the coast. Unlike olive ridleys, East Pacific greens are very

rarely seen associated with floating objects. Turtles are often reported in association with fish

such as dorado and sharks, but it is not always clear whether these are olive ridleys or East Pacific

greens. Although East Pacific greens usually occur singly, they are frequently seen in large

groups, usually near the Galapagos Islands (e.g., a group of 59 was seen in July 1991). Sampling

from large groups always yielded only mature females (IATTC, unpubl. data).

Health Status

Disease in East Pacific green turtle populations has not been studied. McDonald and Dutton

(1990) found early stages of what appear to be fibropapillomas (tumor disease) in several

individuals of the San Diego Bay population. Green turtles residing in certain benthic habitats are

afflicted by lobulated tumors (fibropapillomas) on their skin, scales, scutes, eyes, oral cavities, and

viscera (Balazs and Pooley 1991). The tumors begin as small, localized lesions that rapidly grow

to exceed 30 cm in diameter, greatly interfering with or even prohibiting swimming, feeding,

breathing, or seeing. The lesions have been classified as fibropapillomas, based on established

histologic criteria for tumor classification. The cause of this disease is unknown, but a herpes virus

is highly suspected based on recent research (Herbst 1994). The disease has increased to

epidemic proportions in Hawaii since the mid-1980s. Similar severe outbreaks in green turtles

over the same time period have also been reported in Florida, several Caribbean nations, and at

a few other sites worldwide. The extent of the presence of this disease has yet to be identified

for the East Pacific green turtle.

Massive East Pacific green turtle mortalities, not obviously connected to human activities, have

been reported along the Pacific coasts of Colombia and Costa Rica. During the fall of 1972, 73

moribund sub-adult East Pacific green turtles were observed on Nancite and Naranjo beaches in

Costa Rica. No wounds were evident in the affected turtles; however, they exhibited

gastro-intestinal disorders (Cornelius 1975). In February 1990, a die-off of about 200 adult female

East Pacific green turtles was reported in the northern Pacific coast of Colombia. No wounds or

traumas were apparent. It has been suggested that a contagious disease or drowning by trawlers

may have caused the mortality (D. Amorocho in litt. to J. Woody, FWS, 27 February 1990).

H. Threats 

This section presents a brief overview of threats to East Pacific green turtles, followed by

summaries of major threats in each U.S.-affiliated area. A third section then presents more
13

detailed information specific to each area where this species occurs. "Threats" to sea turtles are

broadly defined as any factor that jeopardizes the survival of turtles or impedes population

recovery. These threat categories are presented, but it is readily apparent that not all are equally

important and that threats in one area may not be relevant in another. Consequently, each

political jurisdiction was evaluated separately based on information received from the Pacific Sea

Turtle Recovery Team and Technical Advisors. (see Table 1). 

Pacific Synopsis

Lack of knowledge concerning the abundance and distribution of Chelonia in the northeastern

Pacific constitutes a threat, particularly since important foraging grounds have not been

specifically identified. Forage areas most likely exist in bays and inlets along the coast of Baja

California (Mexico) and southern California (United States), however, these vital areas cannot be

given adequate protection until they have been identified. The breeding population origins and

migratory habits of East Pacific green turtles frequenting waters off the west coast of the United

States are unknown. Threats to migrating turtles are, therefore, also unknown. This information

is important for effective management. 

Regional Summaries

U.S. West Coast

Primary turtle threats: debris

boat collisions

incidental capture

The primary threats to the species in U.S. waters include incidental capture by coastal fisheries,

boat impacts and water pollution.

Other U.S. Areas

Primary turtle threats: N/A

This regional population does not extend to other U.S. jurisdictions.
a

 There is no known nesting by this species in the United States or in any territory under U.S.

jurisdiction. Therefore, only threats in the marine environment (#12-26) are included in this table.

14

Table 1. Threat checklist for Codes 1 = major problem - = not current problem

East Pacific green sea 2 = moderate problem ? = unknown

turtles in the U.S. 3 = minor problem P = known problem but extent unknown

Pacific Oceana

Threat U.S.

West

Coast 

Hawaii Amer.

Samoa

Guam Palau CNMI RMI FSM Uninc.

Marine Environment

12 Directed take - - - - - - - - -

13 Natural disasters P - - - - - - - -

14 Disease/parasites P - - - - - - - -

15 Algae/Seagrass/reef

degradation

P - - - - - - - -

16 Environmental Contaminants P - - - - - - - -

17 Debris (entangle/ingest) 1 - - - - - - - -

18 Fisheries (incidental take)

-domestic waters 3 - - - - - - - -

-international ? - - - - - - - -

19 Predation ? - - - - - - - -

20 Boat collisions 1 - - - - - - - -

21 Marina/dock development - - - - - - - - -

22 Dredging - - - - - - - - -

23 Dynamite”fishing” - - - - - - - - -

24 Oil exploration/development - - - - - - - - -

25 Power plant entrapment - - - - - - - - -

26 Construction blasting - - - - - - - - -
15

General Threat Information

 This section provides the supportive information used to rank the threats listed in Table 1.

The first 11 threats pertain to the turtle's nesting environment, the latter 15 to the marine

environment.

Nesting Environment

While no East Pacific green turtles nest in U.S. jurisdiction, it is important that the United

States participate in restoration efforts of U.S. sea turtle stocks at their nesting beaches. Thus,

we have chosen to add a general description of nesting beach threats, so that U.S. resource

managers can make informed decisions on policies to support turtles in other political jurisdictions.

1. Directed Take

The harvest of sea turtles and/or their eggs for food or any other domestic or commercial use

constitutes a widespread threat to these species. Removing breeding adults from a population

can accelerate the extinction of local stocks, and the persistent collection of eggs guarantees that

future population recruitment will be reduced. This category includes only the harvest of sea

turtles (typically nesting females) and their eggs on land. Harvest at sea is discussed in a later

section. (see Recovery - Section 1.1.1.1)

2. Increased Human Presence

Human populations are growing rapidly in many areas of the Pacific and this expansion is

exerting increasing pressure on limited coastal resources. Threats to sea turtles include increased

recreational and commercial use of nesting beaches, the loss of nesting habitat to human activities

(e.g., pig pens on beaches), beach camping and fires, an increase in litter and other refuse, and

the general harassment of turtles. Related threats, such as coastal construction, associated with

increasing human populations are discussed separately. (see Recovery - Sections 1.1, 1.2)

3. Coastal Construction

The most valuable land is often located along the coastline, particularly when it is associated

with a sandy beach. Construction is occurring at a rapid rate and is resulting in a loss of sea turtle

nesting areas. This section discusses construction-related threats to the region's sea turtle

nesting beaches, including the construction of buildings (hotels, houses, restaurants), recreational

facilities (tennis courts, swimming pools), or roads on the beach; the construction of sea walls,

jetties, or other armoring activities that can result in the erosion of adjacent sandy beaches;

clearing stabilizing beach vegetation (which accelerates erosion); and the use of heavy

construction equipment on the beach, which can cause sand compaction or beach erosion. (see

Recovery - Sections 1.1.2, 1.2)

4. Nest Predation

The loss of eggs to non-human predators is a severe problem in some areas. These predators

include domestic animals, such as cats, dogs and pigs, as well as wild species such as rats,
16

mongoose, birds, monitor lizards, snakes, and crabs, ants and other invertebrates. (see Recovery

- Section 1.1.3)

5. Beach Erosion

Weather events, such as storms, and seasonal changes in current patterns can reduce or

eliminate sandy beaches, degrade turtle nesting habitat, and cause barriers to adult and hatchling

turtle movements on affected beaches. (see Recovery - Sections 1.1.5.2, 1.2.1 )

6. Artificial Lighting

Hatchling sea turtles orient to the sea using a sophisticated suite of cues primarily associated

with ambient light levels. Hatchlings become disoriented and misdirected in the presence of

artificial lights behind (landward of) their hatching site. These lights cause the hatchlings to orient

inland, whereupon they fall prey to predators, are crushed by passing cars, or die of exhaustion

or exposure in the morning sun. Nesting adults are also sensitive to light and can become

disoriented after nesting, heading inland and then dying in the heat of the next morning, far from

the sea. Security and street lights, restaurant, hotel and other commercial lights, recreational

lights (e.g., sports arenas), and village lights, especially mercury vapor, misdirect hatchlings by the

thousands throughout the Pacific every year. (see Recovery - Sections 1.1.2, 1.1.4)

7. Beach Mining

Sand and coral rubble are removed from beaches for construction or landscaping purposes.

The extraction of sand from beaches destabilizes the coastline (e.g., reduces protection from

storms), removes beach vegetation through extraction or flooding and, in severe cases, eliminates

the beach completely. When mining occurs on or behind a nesting beach, the result can be the

degradation or complete loss of the rookery. In addition, females can become confused when

they emerge from the sea only to find themselves heading down slope into a depression formed

by mining activities; too often the outcome is that the female returns to the sea without laying her

eggs. Even when eggs are successfully deposited, reduced hatch success results if nests are

flooded or excavated during mining. (see Recovery - Section 1.2.2)

8. Vehicular Driving on Beaches

Driving on the beach causes sand compaction and rutting, and can accelerate erosion. Driving

on beaches used by turtles for egg-laying can crush incubating eggs, crush hatchlings in the nest,

and trap hatchlings after they emerge from the nest cavity and begin their trek to the sea. In the

latter case, hatchlings are exposed to exhaustion and predators when they fall into and cannot

climb out of tire ruts that are typically oriented parallel to the sea. (see Recovery - Section 1.2.6)

9. Exotic Vegetation

Introduced species can displace native dune and beach vegetation through shading and/or

chemical inhibition. Dense new vegetation shades nests, potentially altering natural hatchling sex

ratios. Thick root masses can also entangle eggs and hatchlings. (see Recovery - Section 1.2.3)
17

10. Beach Cleaning

Removal of accumulated seaweeds and other debris from a nesting beach should be

accomplished by hand-raking only. The use of heavy equipment can crush turtle eggs and

hatchlings and can remove sand vital to incubating eggs. (see Recovery - Section 1.2.5)

11. Beach Replenishment

The nourishment or replacement of beaches diminished by seawalls, storms, or coastal

development can reduce sea turtle hatching success by deeply burying incubating eggs,

depositing substrate (generally from offshore deposits) that is not conducive to the incubation of

sea turtle eggs, and/or obstructing females coming ashore to nest by machinery, pipelines, etc.

(see Recovery - Section 1.2.4)

Marine Environment

12. Directed Take

The harvest of juvenile and adult sea turtles for food or any other domestic or commercial use

constitutes a widespread threat to these species. In particular, the exploitation of large juveniles

and adults can accelerate the extinction of both local and regional stocks. This category includes

only the harvest of sea turtles at sea. Harvest on the nesting beach was discussed in a previous

section. (see Recovery - Section 2.1) 

While the illegal take of juvenile and adult Chelonia in Mexican waters is not uncommon, no

information exists on the take of this species in U.S. waters. Presumably direct take in the United

States is zero.

13. Natural Disasters

Natural phenomena can contribute to the mortality of turtles at sea, particularly in shallow

waters. Storms can alter current patterns and blow migrating turtles off course into cold water.

Unseasonal warm water incursions from subtropical regions into the northeastern Pacific, known

as "El Niño" events, may cause East Pacific green turtles to migrate north where they "cold stun"

once they encounter colder water. El Niño events can also cause reduced food production for

some turtle species which can reduce growth and fecundity. Increased numbers of stranded East

Pacific green turtles reported along the coasts of California, Oregon and Washington are

associated with these "El Nino" events (Stinson 1984). (see Recovery - Sections 2.1.6, 2.1.7,

2.2.1, 2.2.2)

14. Disease and Parasites

There are few data to assess the extent to which disease or parasitism affects the survivability

of sea turtles in the wild. The "fibropapilloma" tumor disease is widespread in the Hawaiian green

turtle population. This disease is characterized by grayish tumors of various sizes, particularly in

the axial regions of the flippers and around the eyes. This debilitating condition can be fatal.

Neither cause nor cure has been identified. While fibropapillomas have not been observed in the
18

Mexican nesting population (J. Alvarado, Universidad de Michoacán, pers. comm.), some turtles

have been observed with what appears to be beginning stages of the disease in San Diego Bay

(McDonald and Dutton 1990). (see Recovery - Section 2.1.6 )

15. Algae, Seagrass and Reef Degradation

Most sea turtle species depend upon sea grass and/or coral reef habitats for food and refuge.

The destruction or degradation of these habitats is a widespread and serious threat to the

recovery of depleted sea turtle stocks. The general degradation of these habitats can be affected

by eutrophication, sedimentation, chemical poisoning, collecting/gleaning, trampling (fishermen,

skin and SCUBA divers), anchoring, etc. (see Recovery - Section 2.2)

16. Environmental Contaminants

Chemical contamination of the marine environment due to sewage, agricultural runoff,

pesticides, solvents and industrial discharges is widespread along the coastal waters of the

western United States, particularly near the populated inlets and bays of southern California where

East Pacific green turtles are likely to be found. San Diego Bay, the only identified forage area

for Chelonia in the eastern United States (Stinson 1984, Dutton and McDonald 1990a,b), is heavily

polluted with heavy metals and PCBs. This contamination has been shown to cause lesions and

mortality in fish and invertebrates, and small lesions have been observed in some of the turtles

there (McDonald and Dutton 1990). Declining productivity of algal and seagrass communities can

negatively impact the East Pacific green turtles that depend on these communities for nutrition.

(see Recovery - Section 2.2.4)

17. Debris (Entanglement and Ingestion)

The entanglement in and ingestion of persistent marine debris threatens the survival of

Chelonia in the eastern Pacific. Turtles become entangled in abandoned fishing gear, ropes and

nets, and cannot submerge to feed or surface to breathe; they may lose a limb or attract predators

with their struggling. Turtles will also ingest debris such as plastic bags, plastic sheets, plastic

six-pack rings, tar balls, styrofoam, and other refuse. Necropsies of stranded turtles have revealed

mortalities due to ingested garbage resulting in poisoning or obstruction of the esophagus. An

adult East Pacific green turtle was recently found dead in San Diego Bay with monofilament

netting tightly packed in the esophagus (Ron Rhimo, FWS, pers. comm.). (see Recovery - Section

2.1.3)

18. Fisheries (Incidental Take)

Turtles are accidentally taken in several commercial and recreational fisheries. These include

bottom trawls commonly used by shrimp vessels in the Gulf of California, gillnets, traps, pound

nets haul seines and beach seines commonly used in inshore and coastal waters of Baja

California. In addition, trawls, purse seines, hook and line, driftnets, bottom and surface longlines

may kill an as yet unknown number of turtles in different areas of the eastern Pacific.

Although largely undocumented, incidental catch of East Pacific green turtles by shrimp

trawlers is probably a major mortality factor in Mexico (Groombridge 1982). In Central America

large numbers of turtles are caught by shrimp trawlers mainly in Costa Rica, Guatemala and El
19

Salvador. Quantitative estimates have been reported only for Costa Rica where in the early 1980's

estimates of catch by the fleet differed among shrimp captains and ranged from 600 - 2,000

annually (Cornelius 1982). Most of the turtles caught were olive ridleys. Also in Costa Rica, 73

of the 75 dead turtles (mortality probably related to shrimp trawling) that washed up on Nancite

and Naranjo beaches in October and November of 1971 were young East Pacific green turtles.

More recently, nearly all of the 22 turtle carcases found along the shore of Murcielago Sector of

Santa Rosa Park in October 1983 were young East Pacific green turtles (Cornelius 1986). Greens

comprised 14% of the annual observed take of all species of turtles by the Hawaiian-based

longline fishery between 1990-1994 (National Marine Fisheries Service [NMFS] 1995) and these

may include East Pacific green turtles. The predicted annual take level by this fishery is 119 green

turtles and although most are recovered and released alive, the post-release mortality remains

unknown. While these numbers appear to be relatively low, they could be significant if the animals

affected belong to severely depleted stocks. (see Recovery - Section 2.1.4)

19. Predation

 Few predators, with the notable exception of orcas (killer whales), large sharks, and marine

crocodiles, can consume a full-size sea turtle. Predation on hatchlings is believed to be relatively

high and, again, the species most often implicated are coastal and pelagic sharks. Billfish attacks

on East Pacific green turtles have also been documented (Frazier et al. 1994).

20. Boat Collisions

Sea turtles can be injured or killed when struck by a boat, especially an engaged propeller.

Recreational equipment, such as jet skis, also pose a danger due to collisions and harassment.

Eighty percent of the Chelonia deaths reported recently in San Diego Bay and Mission Bay,

California were associated with evidence of boat collision (McDonald and Dutton 1992). (see

Recovery - Sections 2.1.4, 2.1.5, 2.1.7) 

21. Marina and Dock Development

The development of marina and docking facilities pose direct and indirect threats to sea turtles.

Direct consequences can be seen when foraging grounds and nesting beaches are dredged or

otherwise permanently altered in the process of construction and maintenance. Altered current

patterns and increased levels of ship traffic, pollution, and general activity which displace or injure

local sea turtles constitute indirect consequences that should also be considered. Fueling facilities

at marinas can result in discharge of oil and gas into sensitive estuarine habitats. There is

increasing demand to install marinas and docks and develop inland coastal areas where turtles

are known or are likely to exist in Baja California and southern California. (see Recovery -

Sections 1.2.1, 2.2)

22. Dredging

Turtles may be injured or killed by active dredging machinery. Dredging may also indirectly

harm turtles by destroying forage habitat. In San Diego Bay, juvenile and adult turtles spend most

of their time motionless on the floor of dredge channels (Stinson 1984, McDonald and Dutton

1992). Periodic dredging may injure or kill these turtles. (see Recovery - Section 2.2.5)
20

23. Dynamite “Fishing”

 The use of explosives to stun or kill fish destroys benthic habitat, degrading or eliminating

foraging habitat and refugia for all sea turtle species (except the leatherback). (see Recovery -

Section 2.2.7)

24. Oil Exploration and Development

Oil exploration and development pose direct and indirect threats to sea turtles. A rise in

transport traffic increases the amount of oil in the water from bilge pumping and disastrous oil

spills. Oil spills resulting from blow-outs, ruptured pipelines, or tanker accidents, can kill sea

turtles. Indirect consequences include destruction of foraging habitat by drilling, anchoring, and

pollution. While oil exploration is currently limited by regulation in U.S. waters, recent proposals

to allow drilling on the California coast are cause for concern. Any such exploration should be

carefully evaluated for impact to East Pacific green populations before such explorations are

undertaken. (see Recovery - Section 2.2.8)

25. Power Plant Entrapment 

The entrainment and entrapment of juvenile and adult East Pacific green turtles in the

saltwater cooling intake systems of coastal power plants have been documented in southern

California at San Diego Gas & Electric (SDG&E) plants in South Bay and Encina, as well as the

southern California Edison Nuclear Generating Station at San Onofre (Kent Miles, SDG&E, pers.

comm.; Joe Cordaro, NMFS, pers. comm.). Some of these turtles are released unharmed.

26. Construction Blasting

Blasting can injure or kill sea turtles in the immediate area. The use of dynamite to construct

or maintain harbors, break up rock formations or improve nearshore access can decimate sea

turtle habitat. Anchoring and related activities employed in support of the blasting can also

degrade benthic habitat, grasses and other benthic communities that support sea turtles. Some

types of dynamiting have minimal impact to marine life, such as placing explosive in pre-drilled

holes (drilling and shooting) prior to detonation and is the standard practice to secure armor rock.

(see Recovery - Section 2.2.7)
21

I. Conservation Accomplishments

Nesting Environment

Nest poaching was very common on the Mexican Pacific coastline until 1980 when protection

efforts were initiated on the major nesting grounds of the East Pacific green turtle in North

America; the beaches of Colola and Maruata Bay, Michoacàn, Mexico. Prior to this the majority

of the thousands of nests deposited annually were lost to poaching. Since 1980, between 85-

95% of nests have been protected in beach hatcheries. The overall hatch success has exceeded

70% in most years. Along with the basic information on nest numbers, clutch size, and hatching

success, the Colola-Maruata project has included additional studies of post-reproductive

migrations, reproductive behavior, remigration intervals, and effects of incubation temperature on

hatchling sex ratios. In 1986, Colola and Maruata beaches were declared natural reserves for the

conservation of sea turtles. Any human activities within or around these reserves that may

endanger nesting females, nests or nesting habitat were prohibited. At a national level, Mexico

banned the harvest of sea turtles and their eggs in 1990. These actions, along with field

conservation efforts, ensure the long term protection of the most important East Pacific green

turtle rookery in North America.

Since the Galapágos Islands are a National Park, all East Pacific green turtle nesting beaches

are completely protected and egg poaching is very rare at that archipelago.

Marine Environment

Thousands of East Pacific green turtles were captured in Mexican waters before 1984. In that

year the fishery for this species was closed. Therefore, the commercial exploitation of this species

is currently prohibited throughout its distributional range in the east Pacific. Incidental capture by

shrimp vessels is now the single most important mortality factor for this species in the marine

environment. Requiring use of TEDs (Turtle Excluder Device) by shrimp vessels in the region will

certainly curtail incidental take.

In Mexico an important effort is being made by governmental agencies, non-governmental

conservation organizations and educational institutions to increase public awareness of sea turtle

conservation issues. The Universidad de Michoacán and Ecotonia, A.C. have produced and

distributed a number of audiovisual and printed material about the East Pacific green turtle.

School children in the settlements of Maruata and Colola are being introduced to the problems that

the sea turtles encounter and ways in which local people can help them. 

In the United States, East Pacific green turtles are protected under the Endangered Species

Act (ESA) of 1973, as amended. The resident population in San Diego Bay is theoretically

protected by a ban on high speed boat traffic in the south portion of the bay; however, this ban

is rarely enforced.
22

II. RECOVERY

A. Recovery Objectives

Goal: The recovery goal is to delist this regionally important population.

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) 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.

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

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

Rationale: Determining quantifiable values that can be used to determine when a sea turtle stock

is recovered is quite difficult. The recovery team has tried to make such recommendations as

listed above based on best available information with the following conceptual guidelines:

1) The minimum nesting stock must equal a size that could not easily be eliminated by a

single catastrophic event ("natural" or "man induced").

2) Nesting population trends should be long enough to minimize the effects of natural

fluctuations in numbers that are characteristic of sea turtle populations. Generally this time

period is equal to the estimated one generation time for each species.

3) Habitats are adequate to support population growth once threats have been reduced or

eliminated.

4) If a species is to be considered for delisting, a plan must already be in force for maintaining

the population in stable or increasing condition. The team was concerned that if a species was

delisted, and no management plan was already in force, that the species may be driven back

toward extinction too rapidly for resource management agencies to implement such plans.
23

B. Step Down Outline and Narrative for Recovery

1 NESTING ENVIRONMENT

While it is recognized that there is no nesting by this species in U.S. jurisdiction, we felt that a

description of recovery actions should be provided so that U.S. agencies could take them into

account when providing support to those nations in which U.S. stocks may nest.

1.1 Protect and manage turtles on nesting beaches.

It is prudent to preserve the capacity of a population to recover from a depleted state by

protecting nesting females, their nests and hatchlings and to preserve the quality of the

nesting area. The killing of gravid females, poaching of nests, predation (native and feral),

destruction of the habitat through mining, destruction of vegetation, artificial lighting,

development, and increased human use all degrade the ability of depleted populations to

recover. Although there are no known nesting grounds for East Pacific green turtles in the

U.S. Pacific, we support the efforts of Mexico and Central American nations with nesting

grounds to preserve their East Pacific green turtle nesting populations. The following tasks

may be used as guidelines to enhance the reproductive ability of these sea turtle populations

at the nesting grounds. 

1.1.1 Eliminate directed take of turtles and their eggs.

Direct take of nesting turtles and their eggs has been identified as a primary threat to

Pacific sea turtle populations. Eliminating this threat is required if populations are to

recover.

1.1.1.1 Reduce directed take of turtles through public education and information.

While increased law enforcement will be effective in the short term, without support

of the local populace, regulations will become ineffective. Education of the public

as to the value of conserving sea turtles, is a very effective way of sustaining

recovery efforts and providing support for enforcement of management regulations.

1.1.1.2 Increase enforcement of laws protecting turtles by law enforcement and the courts.

Lack of adequate support for law-enforcement activities which protect sea turtle

populations is common, yet it must be understood that enforcement is as important

as any other resource management activities. Enforcement, judicial and

prosecutorial personnel must receive adequate resources as well as instruction

about sea turtles and the importance of protecting turtle populations.

1.1.2 Ensure that coastal construction activities avoid disruption of nesting and hatching

activities.

Coastal construction must be monitored to minimize impact on turtle beaches, both during

construction, particularly during the nesting and hatching season and in the long-term.
24

Construction equipment must not be allowed to operate on the beach, remove sand from

the beach, or in any way degrade nesting habitat. Nighttime lighting of construction areas

should be prohibited during nesting and hatching seasons. In the long-term, structures

should not block the turtle’s access to the beach, change beach dynamics, or encourage

human activities that might interfere with the nesting process.

1.1.3 Reduce nest predation by domestic and feral animals.

Feral animals such as dogs and mongooses pose a severe threat to turtle nests and

hatchlings. It is important that feral predators be controlled or eliminated from nesting

areas. Domestic animals such as pigs or dogs can also threaten turtle nests and

hatchlings, and should be controlled near nesting areas. In particular, domestic dogs

should not be allowed to roam turtle nesting beaches unsupervised.

1.1.4 Reduce effects of artificial lighting on hatchlings and nesting females.

Because sea turtles (especially hatchlings) are extremely attracted to artificial lighting,

lighting near nesting beaches should be placed in such a manner that light does not shine

on the beach. If not, turtles may become disoriented and stray from their course.

1.1.4.1 Quantify effects of artificial lighting on hatchlings and nesting females.

It is important to quantify the impact of existing lighting in terms of nesting success

and hatchling survival so that pragmatic mitigation can be applied. Also such study

can be used to guide the development of effective lighting ordinances. 

1.1.4.2 Implement, enforce, evaluate lighting regulations or other lighting control measures

where appropriate.

Shielding of the light source, screening with vegetation, placing lights at lowered

elevations and in some cases the use of limited spectrum low wavelength lighting

(e.g., low pressure sodium vapor lights) are possible solutions to beach lighting

problems. Such measures should be required by law and enforced.

1.1.5 Collect biological information on nesting turtle populations.

The collection of basic biological information on nesting is critical for making intelligent

management decisions. Monitoring nesting success can help to identify problems at the

nesting beach or elucidate important areas for protection. Analyzing population

recruitment can help in understanding population status.

1.1.5.1 Monitor nesting activity to Identify important nesting beaches, determine number

of nesting females, and determine population trends.

Important nesting beaches (based on actual number of nests) must be identified

for special protection. Nesting beaches need to be identified by standardized

surveys during the nesting season. Informational surveys with local residents and

officials should be conducted to determine current or historical nesting beaches.
25

One of the most crucial techniques for determining the status of sea turtle

populations and for evaluating the success of management or restoration programs

is long-term monitoring of annual nesting on key beaches. The surveys must be

done in a standardized and consistent manner with experienced personnel. Since

female turtles show fidelity to nesting beaches, long term beach censusing

provides a ready means for assessing these maternally isolated populations.

However, because of long maturity times for turtles, quantifying trends in

population sizes and effectiveness of any restoration program may take a

generation time (20+ years) to be reflected in the annual numbers of nesters.

Monitoring should thus be recognized as a long-term undertaking.

1.1.5.2 Evaluate nest success and implement appropriate nest-protection measures on

important nesting beaches.

One of the simplest means to enhance populations is by increasing hatchling

production at the nesting beach. The first step to such an enhancement program

is to determine the nesting / hatching success and to characterize factors which

may limit that success. Once those limiting factors are determined, protection or

mitigation measures can be implemented. If nests must be moved to prevent loss

from erosion or other threats, natural rather than artificial incubation should be

employed.

1.1.5.3 Define stock boundaries for Pacific sea turtles.

Because sea turtles exhibit a unique genetic signature for each major nesting

assemblage, and because nesting assemblages provide an easily censused

means of monitoring population status, it is useful to use genetic analysis methods

to determine stock boundaries for sea turtle populations. It also enables managers

to determine which stocks are being impacted by activities far removed from the

nesting beaches, and thus prioritize mitigation efforts.

1.1.5.3.1 Identify genetic stock type for major nesting beach areas.

A “genetic survey” to establish the genetic signature of each nesting

population must be established, before stock ranges can be determined.

Such surveys are relatively simple as they require only a small blood

sample from a statistically viable number of females within each nesting

population.

1.1.5.3.2 Determine nesting beach origins for juvenile and subadult populations.

Because nesting populations can form the basis for stock management, it

is important to be able to pair juvenile and subadult turtles with their stock

units by genetic identification. DNA analyses have begun to provide

scientists and managers with this sort of data. 

1.1.5.3.3 Determine the genetic relationship among East Pacific green turtle

populations and within the Pacific.
26

The need for such study is critical to successful management of a sea turtle

population as it enables resource managers to identify the entire (and often

overlapping) range of each population. This type of population study can

also detail the genetic diversity and viability of the populations.

1.2 Protect and manage nesting habitat.

The nesting habitat must be protected to ensure future generations of the species. Increased

human presence and coastal construction can damage nesting habitat resulting in reduced

nest success or reduced hatchling survival.

Once key nesting beaches are identified, they may be secured on a long-term basis in an

assortment of ways. These may include conservation easements or agreements, lease of

beaches, and in some cases, fee acquisition. Certain beaches may be designated as natural

preserves. In some cases education of local residents may serve to adequately secure

nesting beaches.

1.2.1 Prevent the degradation of nesting habitats caused by sea walls, revetments, sand bags,

other erosion-control measures, jetties and breakwaters. 

Beach armoring techniques that beach residents use to protect their beachfront properties

from wave action may actually degrade nesting habitats by eroding beaches and

preventing nesting by preventing access to nesting sites or preventing digging of the nest

on the site. Guidelines on the proper placement of stonewalls must be proposed. Jetties

and breakwaters impede the natural movement of sand and add to erosion problems in

neighboring beaches. Regulations regarding beach construction and beach armoring

should be reviewed to ensure that such measures are restricted or prohibited if adverse

impacts to nesting are anticipated.

1.2.2 Eliminate sand and coral rubble removal and mining practices on nesting beaches.

Beach mining severely affects a nesting beach by reducing protection from storms,

destroying native vegetation directly or indirectly and may completely destroy a nesting

beach. Protective legislation and public education must be used to protect the substrate

of the beaches.

1.2.3 Develop beach-landscaping guidelines which recommend planting of only native

vegetation, not clearing stabilizing beach vegetation and evaluating the effects as

appropriate.

Non-native vegetation may prevent access to nesting sites, prevent adequate nest digging,

exacerbate erosion or affect hatchling sex ratios by altering incubation temperatures.

Native vegetation, however, plays an important role in stabilizing the beach and creating

the proper microclimate for nests. Guidelines for residents concerning the most appropriate

plant species and the importance of a native plant base should be encouraged.
27

1.2.4 Ensure that beach replenishment projects are compatible with maintaining good quality

nesting habitat.

Sand on sea turtle beaches has particular properties which affect hatching success (ie.

compaction, gas diffusion, temperature). Any addition or replacement of sand may change

these properties and make it more difficult for females to nest or reduce hatchling success.

As such, beach replenishment projects should be carefully considered, use materials

similar to the native sands and be carried out outside the nesting season. 

1.2.5 Implement non-mechanical beach cleaning alternatives.

Hand raking of beach debris, rather than using heavy machinery, should be encouraged

on nesting beaches where cleaning is done for aesthetic reasons. The use of heavy

machinery can adversely affect hatchlings directly and their nesting habitat. 

1.2.6 Prevent vehicular driving on nesting beaches.

Driving on active nesting beaches should be forbidden. Vehicles cause destabilization of

beaches, threaten incubating nests and leave tire ruts that hatchlings have difficulty

crossing.

2 MARINE ENVIRONMENT

2.1 Protect and manage East Pacific green turtle populations in the marine habitat.

Protection of turtles in the marine environment is a priority that is often overlooked as

enforcement is difficult and quantification of the problem problematic. However, 99% of a

turtle’s life is spent at sea; thus, recovery must include significant efforts to protect turtles at

that time. As their distribution in the marine habitat of the U.S. Pacific is limited, we must

encourage and support recovery efforts in other Pacific nations where the turtle species is

found.

2.1.1 Eliminate directed take of turtles.

Direct take of turtles was identified as a severe threat to population recovery in the Pacific

Ocean and must be eliminated if sea turtles are to recover.

2.1.1.1 Reduce directed take of turtles through public education and information.

While increased law enforcement will be effective in the short term, without support

of the local populace, regulations will become ineffective. Education of the public

as to the value of conserving sea turtles, is a very effective way of sustaining

recovery efforts and providing support for enforcement of management regulations.

(Also see Section 4).

2.1.1.2 Increase the enforcement of protective laws on the part of law enforcement and the

courts.
28

One of the major threats identified for turtle populations in the Pacific was the

illegal harvest of turtles both on the nesting beach and in the water. Rigorous

efforts in law enforcement should be undertaken immediately to reduce this source

of mortality. Such efforts need to include training of enforcement personnel in the

importance of protecting turtles, as well as supplying such personnel with adequate

logistical support (boats, communication and surveillance equipment etc.). Judges

and prosecutors must also be educated in the importance of these matters. 

2.1.2 Determine distribution, abundance, and status in the marine environment.

In its review of information on sea turtle populations in the Pacific, the Recovery Team

found that lack of accurate information on distribution and abundance was one of the

greatest threats to sea turtle populations. While excellent information on nesting for some

areas of Mexico is available, particularly in Michoacán, there is a general lack of

information on the regional population size and status. We consider that gathering of

basic information on distribution and abundance should be a very high priority activity

toward the recovery of East Pacific green turtle populations.

2.1.2.1 Determine the distribution and abundance of post-hatchlings, juveniles and adults.

While little is known about the distribution of nesting beaches for the East Pacific

green turtle, even less is understood about distribution of foraging adult and

juvenile populations. Quantitative surveys of foraging areas to determine their

abundance, and to identify essential habitat is of significant importance for

restoration of East Pacific green turtle populations.

2.1.2.2 Determine adult migration routes and inter-nesting movements.

Like all species of sea turtle (with the possible exception of the Flatback turtle,

Natator depressus), East Pacific green turtles migrate from foraging grounds to

nesting beaches. These migrations often mean that the turtles move through a

variety of political jurisdictions where regulations regarding the stewardship of the

species may vary. To preclude the problem of contradictory management

strategies by these various jurisdictions, it is important to determine the migration

routes East Pacific green turtles follow between nesting and foraging areas.

Satellite telemetry studies of both males and females are needed.

2.1.2.3 Determine growth rates and survivorship of hatchlings, juveniles, and adults, and

age at sexual maturity.

Understanding the rates of growth and survivorship of turtle populations is crucial

to the development of appropriate population models. Such models are important

in understanding population status and how best to efficiently apply management

efforts, in restoring depleted populations. For example, the application of stagebased modeling (Crouse et al. 1987) indicated that not enough effort was being

expended on protecting juvenile sized loggerhead sea turtles in the southeastern

United States and that without such protection, extensive nesting beach protection
29

was having less positive benefit. A similar approach to understanding East Pacific

green turtle populations should be undertaken, and used to guide restoration

policy.

2.1.2.4 Identify current or potential threats to adults and juveniles on foraging grounds.

Little is known about threats to foraging populations of East Pacific green turtles.

Studies on such threats should be undertaken immediately.

2.1.3 Reduce the effects of entanglement and ingestion of marine debris.

Entanglement due to abandoned or unmonitored fishing gear, as well as the ingestion of

man-made debris is a significant problem in the marine environment. 

2.1.3.1 Evaluate the extent to which sea turtles ingest persistent debris and become

entangled.

Quantification of the extent to which sea turtles are impacted by marine debris

should be undertaken as a first step to mitigating or preventing such impacts. The

benefits of such work are that it allows the prioritization of recovery activities and

it allows the activities to be efficiently targeted at the problem. 

2.1.3.2 Evaluate the effects of entanglement and ingestion of persistent debris on health

and viability of sea turtles.

Because of the remote nature of turtle/debris interactions, the acute and chronic

effects of such interaction are not often understood. Turtles may not die

immediately after ingesting certain materials, but may become debilitated. Studies

to further understand the impacts of such interactions, and what age classes are

affected most severely, should be undertaken immediately. As with quantifying the

extent to which sea turtles ingest debris, such a program allows recovery efforts to

be more efficient.

2.1.3.3 Formulate and implement measures to reduce or eliminate persistent debris and

sources of entanglement in the marine environment.

Once the problem of marine debris has been identified and quantified, it is

important to implement (and enforce) a program to reduce the amount of debris in

the marine environment, ie. removing the problem entirely.

2.1.4 Monitor and reduce incidental mortality in the commercial and recreational fisheries.

 For some areas, incidental take in fisheries has been identified as a severe threat. These

mortalities are often associated with international fleets operating on the high seas, but for

the coastal dwelling East Pacific green turtle it is probably most significant in nearshore

waters. Monitoring of turtle take by fisheries is extremely important for two reasons. First,

it allows resource managers a means to quantify the extent of the problem, and by the very

act of monitoring, tends to cause commercial fishermen to be more aware of the concern
30

over incidental take, and thereby encourage reduced take. The choice method for

monitoring take is through the use of an unbiased observer program. Voluntary logbooks

have not proven a reliable technique for quantifying incidental catch in commercial

fisheries. Implementation of mortality reduction activities includes the use of TEDs in

shrimp trawler fisheries. 

2.1.5 Eliminate the harassment of turtles at sea through public education and enforcement.

Activities such as “petting” turtles and chasing them while snorkeling and scuba diving,

water skiing, jet skis, vessel traffic, and vessel anchoring may disturb or displace turtles.

These factors should be regulated or controlled to eliminate negative impacts, especially

in sensitive and high density foraging and resting areas.

2.1.6 Study the impact of diseases on turtles.

Little is known about diseases in sea turtles, but there has been recent evidence that it

may be a limiting factor in certain populations. Disease origin and transmission may not

be limited to the marine environment.

2.1.6.1 Determine prevalence of fibropapillomatosis in population.

Debilitating and life threatening tumors are known to occur in populations of green

turtles. The magnitude of this disease during recent years has increased

substantially in some areas although the extent of the disease is unknown in the

east Pacific green turtle. The etiology of the disease and effects as they relate to

the viability of the population are presently unknown and need to be studied.

2.1.6.2 Investigate parasites and other infectious agents.

A variety of other diseases and parasites may be affecting sea turtles. The

prevalence of such infections, their impact on sea turtles, and modes of

transmissions need to be studied. Parasites include internal parasites such as

blood flukes, external parasites such as leeches (Ozobranchus) and burrowing

barnacles (Stephanolepas), and certain bacterial infections such as Vibrios.

2.1.7 Maintain carcass stranding network.

Stranding networks are operated generally by volunteers who monitor beaches for

stranded animals. Such networks can be useful for alerting managers to incidents causing

high mortality, such as an increased fishery take or disease problems, as well as providing

some basic biological data. 

2.1.8 Centralize administration and coordination of tagging programs.

In general, government resource management agencies can provide the continuity

required to coordinate tagging programs. The responsibility of any such agency is that

they act as a central distribution point for tags, tagging training and database

management. It is critically important that the coordinating agency: 1) provides adequate
31

staff to keep the program organized and respond to tag returns immediately, and 2) remain

in existence for many years (20+). Without such a commitment, tagging programs have

very limited usefulness, and before initiation of such a program it should be considered

carefully on its scientific merits. It must be remembered that sea turtles are long-lived

animals, and the most valuable information yielded by any tagging program comes from

turtles which have carried identification tags for many years. Short-term tagging projects

are at best very limited in the information they yield and at worst are nothing more than a

form of undue harassment to the turtles. 

Centralization of tag records is useful as it makes the most efficient use of limited

personnel resources, allows standardization of techniques, and can act as a screening

mechanism to ensure that tagging is done for valid scientific reasons.

2.2 Protect and manage marine habitat, including foraging habitats.

East Pacific green turtles inhabit a variety of marine habitats, although we are most familiar

with their coastal habitat. Increased human presence in this and other sea turtle habitats have

contributed to habitat degradation, primarily by coastal construction, increased recreational

and fisheries use, and increased industrialization. Habitat loss and degradation must be

prevented or slowed.

2.2.1 Identify important marine habitats.

These areas may include hatchling, juvenile and adult foraging areas and migratory range

for all age classes. (Many of these areas will first need to be identified through actions in

Section 2.1.2.1 and 2.1.2.2.)

2.2.2 Ensure the long-term protection of marine habitat.

Once marine habitats are identified, sea turtle range, refugia and foraging habitats

(Sargassum beds, coral reefs or seagrass and algal beds, estuarine habitats) need to be

protected to ensure long-term survival for the species. Habitats identified as important or

critical should be designated as marine sanctuaries or preserves, while others may require

close monitoring. The public needs to be educated on the importance of preserving these

habitats.

2.2.3 Assess and prevent the degradation or destruction of reefs and seagrass beds caused by

boat groundings, anchoring, and trampling by fishermen and divers. 

This is not an issue for the East Pacific green turtle due to minimum amounts of such

habitat within the species distribution.

2.2.4 Prevent the degradation of reef habitat caused by environmental contaminants such as

sewage and other pollutants.

This is not an issue for the East Pacific green turtle due to minimum amounts of such

habitat within the species distribution.
32

2.2.5 Prevent the degradation or destruction of marine habitats caused by dredging or disposal

activities.

Dredging causes mechanical destruction of benthic habitats, adds suspended sediments

that may damage algae and seagrasses and disposal of dredged materials smothers

existing flora and fauna. Some types of dredging also kill turtles directly.

2.2.6 Prevent the degradation or destruction of important habitats caused by upland and coastal

erosion and siltation. 

These processes, often made worse by coastal construction, adversely affect coastal

habitats by disrupting vital trophic processes, reducing productivity and reducing species

diversity. Minimum water standards upstream must be maintained. Land-use decisions

must take this into account and associated projects where erosion and siltation occur must

be monitored.

2.2.7 Prevent the degradation or destruction of reefs by dynamite fishing and construction

blasting.

Blasting of any nature physically damages reefs and may kill turtles. It must be monitored

and/or restricted.

2.2.8 Prevent the degradation of coastal habitats caused by oil transshipment activities.

Oil spills from tankers are a possible threat both to coastal and pelagic habitats. Also,

groundings or collisions of tankers and other petroleum industry vessels may physically

damage reefs, perhaps more so than other vessels because of their sheer size (see

Section 2.2.3). The oil and gas industry should take necessary preventive measures (e.g.

double hulled tankers). Oil spill response teams should be identified for all likely areas.

 

2.2.9 Identify other threats to marine habitat and take appropriate actions.

Such threats to sea turtle habitat that do not fit in the previous sections or new threats

must be considered and addressed. 

3 ENSURE PROPER CARE IN CAPTIVITY.

Captive care of sea turtles is common in the Pacific. Most of this care is in the form of formal

rearing programs. Depending on the scale of such activities such captivity can be harmful to the

wild population due to excess take from the wild, or from the potential introduction of exotic

diseases or unfit genetic stocks to the wild population. Captive care should be carefully regulated

to minimize such problems, and all release programs should rigorously monitor the status of

released turtles to ensure their proper integration into the wild. It should be noted that to be

deemed successful, wild turtles should be shown not only to survive in the wild but should also

successfully reproduce. If released turtles do not reproduce, such populations will never be self

sustaining. 
33

3.1 Develop standards for the care and maintenance of sea turtles, including diet, water quality,

tank size, and treatment of injury and disease.

Standards should be developed by NMFS or other appropriate agencies. Once developed,

these criteria should be published and set as requirements for any sea turtle holding facility.

Facilities that comply with the criteria will receive permits to hold turtles and be inspected for

compliance. A manual for diagnosis and treatment of sea turtle diseases should be compiled,

published and distributed to holding facilities. 

3.2 Establish a catalog of all captive sea turtles to enhance use for research and education.

The FWS and NMFS should establish a catalog of turtles at all known facilities and include

basic biological data and genetic origin.

3.3 Designate rehabilitation facilities.

FWS, NMFS and other appropriate agencies should designate these facilities based on the

above criteria. Designation should be based on availability of appropriate veterinary

personnel, compliance with standards of care and annual inspections. Recommendations

should be made on when and where hatchlings or adults should be released based on the

origin of rehabilitated turtles, as determined by genetic analysis (Encalada et al. 1994). 

4 INTERNATIONAL COOPERATION.

4.1 Support existing international agreements and conventions to ensure that turtles in all lifestages are protected in foreign waters.

Considering that East Pacific green turtles migrate outside of U.S. territorial waters during at

least part of their life cycle, an effective recovery plan must include supporting existing

cooperative agreements with other nations to protect the species. Existing agreements

include CITES (see next section, adopted 1973), the Convention on Nature Protection and

Wildlife Preservation in the Western Hemisphere (adopted 1940), the ASEAN Agreement on

the Convention of Nature and Natural Resources (adopted 1985), the Convention for the

Protection of the Natural Resources and Environment of the South Pacific Region (SPREP

convention, adopted 1986), as well as a number of conventions concerning marine pollution

(Eckert, 1993). 

4.2 Encourage ratification of CITES for all non-member Pacific countries, compliance with CITES

requirements, and removal of sea turtle trade reservations held by member nations.

CITES is a comprehensive wildlife treaty signed by many countries that regulates and prohibits

commercial import and export of wild plant and animal species that are threatened by trade.

In the north Pacific signatories include 18 countries (Eckert, 1993). It is one of the most

powerful international agreements concerning threatened species. The U.S. State

Department, Department of Commerce and Department of Interior should work with Pacific

nations to encourage non-member countries to become signatories and demand compliance

with CITES requirements on sea turtles from all signatories.
34

4.3 Develop new international agreements to ensure that turtles in all life-stages are protected

in foreign waters.

New agreements must be outlined by the FWS and NMFS, and pursued by the State

Department and Department of the Interior.

4.4 Develop or continue to support informational displays in U.S. airports and ports of entry which

have direct flights to Mexico and Latin America.

Airports are particularly good avenues for information about illegal trade in tortoise and

tortoiseshell paraphernalia, as well as general information on sea turtle conservation. If

travelers don’t purchase the items, the market for them may decrease. Agencies such as

NMFS, FWS and the U.S. Customs Service should collaborate on display content and

placement.
35

III. REFERENCES CITED

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Alvarado, J., and A. Figueroa. 1989. The ecological recovery of sea turtles of Michoacan,

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Bocourt, M. 1868. Description de quelques cheloniens nouveaux appartenant a la faune

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Brongniart, A. 1800. Essaid’une classification naturelle des reptiles. Bull. Sci. Soc. Philomat.

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Byles, R., J. Alvarado, and D. Rostal. 1995. Preliminary analysis of post-nesting movements of

the black turtle (Chelonia agassizi) from Michoacan Mexico. Pages 12-13 in: Proc. of the

Twelfth Annual Workshop on Sea Turtle Biology and Conservation. NOAA Tech. Memo.

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Caldwell, D.K. 1962. Sea turtles in Baja California waters (with special reference to those of the

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Caldwell, D.K. 1963. The sea turtle fishery of Baja California, Mexico. Calif. Fish Game

49(3):140-151.

Carl, G.C. 1955. The green turtle in British Columbia. Report of the Provincial Museum of

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alimenticios de Lepidochelys olivacea y Chelonia mydas agassizi (Reptilia, Cheloniidae)

en el Pacifico mexicano. Bolm. Inst. Oceanogr., S. Paulo, 29(2):87-89.

Cliffton, K., D.O. Cornejo, and R.S. Felger. 1982. Sea turtles of the Pacific coast of Mexico.

Pages 199-209 in K.A. Bjorndal (ed.), Biology and Conservation of Sea Turtles.

Smithsonian Inst. Press, Washington, D.C. 583 pp.

Cornelius, S.E. 1975. Marine turtle mortalities along the Pacific coast of Costa Rica. Copeia

1:186-187.

Cornelius, S.E. 1976. Marine turtle nesting activity at Playa Naranjo, Costa Rica. Brenesia

8:1-27.

Cornelius, S.E. 1982. Status of sea turtles along the Pacific coast of Middle America. Pages

211-219 in K.A. Bjorndal (ed.), Biology and Conservation of Sea Turtles. Smithsonian Inst.

Press, Washington, D.C. 583 pp.

Cornelius, S.E. 1986. The sea turtles of Santa Rosa National Park. Fundacion de Parques

Nacionales Costa Rica. 64 pp.

Crouse, O.T., Crowder, L.B. and Caswell, H. 1987. A stage based population model for

loggerhead sea turtles and implications for conservation. Ecology 68(5):1412-1423.

Dutton, P.H., and D.L. McDonald. 1990a. Sea turtles present in San Diego Bay. Pages 139-141

in T. H. Richardson, J.I. Richardson, and M. Donnelly (compilers), Proc. Tenth Annual

Workshop on Sea Turtle Biology and Conservation. U.S. Dep. Commer., NOAA Tech.

Memo. NMFS-SEFC-278. 
37

Dutton, P.H., and D.L. McDonald. 1990b. Status of sea turtles in San Diego Bay, 1989 - 1990

Final Report. Sea World Research Institute Technical Report #90-225. 18 pp.

Dutton, P.H., and D. McDonald. 1992. Tagging studies of sea turtles in San Diego Bay, 1990 -

1991. Pages 35-38 in Proc. Eleventh Annual Workshop on Sea Turtle Biology and

Conservation. U.S. Dep. Commer., NOAA Tech. Memo. NMFS-SEFC-304.

Dutton, P.H., S.K. Davis, T. Guerra, and D.W. Owens. 1996. Molecular phylogeny for marine

turtles based on sequences of the ND4-leucine tRNA and control regions of mitochondrial

DNA. Mol. Phylogenet. Evol. 5:511-521. 

Dutton, P.H., S.K. Davis, D.L. McDonald, and T. Guerra. 1994. A genetic study to determine the

origin of the sea turtles in San Diego Bay, California. Pages 55-56 in B.A. Schroeder and

B.E. Witherington (compilers), Proceedings of the Thirteenth Annual Symposium on Sea

Turtle Biology and Conservation. NOAA Tech. Memo. NMFS-SEFSC-341. 281 pp.

Eckert, K.L. 1993. The biology and population status of marine turtles in the north Pacific Ocean.

NOAA Tech. Memo. NMFS-SWFSC-186. 156 pp.

Encalada, S.E., Eckert, S.A., and Bowen, B.W. 1994. Forensic applications of mitochondrial

DNA markers: origin of a confiscated green turtle. Mar. Turtle Newsl. 66:1-3.

Felger, R.S., K. Cliffton, and P.J. Regal. 1976. Winter dormancy in sea turtles: independent

discovery and exploitation in the Gulf of California by two local cultures. Science

191:283-285.

Felger, R.S., and M.B. Moser. 1987. Sea turtles in Seri Indian culture. Environ. Southwest, Fall

1987:18-21.

Figueroa, A. 1989. Contribucion a la determinacion del status taxonomico de la tortuga negra

(Chelonia agassizii Bocourt, 1868) de Michoacan, Mexico. UMSNH Escuela de Biologia,

(Tesis Prof.). 73 pp.

Frazier, J.G., H. Fierstine, S.C. Beavers, F. Achaval, H. Suganuma, R.C. Pitman, Y. Yamaguchi,

and C.Ma. Prigioni. 1994. Impalement of marine turtles (Reptilia, Chelonia: Cheloniidae

and Dermochelyidae) by billfishes (Osteichthyes, Perciformes: Istiophoridae and

Xiphiidae). Env. Biol. of Fishes 39:85-96.

Fritts, T.H. 1981. Pelagic feeding habits of turtles in the eastern Pacific. Mar. Turtle Newsl.

17:4-5.

Green, D. 1984. Long-distance movements of Galapagos green turtles. J. Herpetol.

18(2):121-130.

Green, D. 1994. Galapagos sea turtles: An overview. Pages 65-68 in B. A. Schroeder and B. E.

Witherington (compilers), Proceedings of the Thirteenth Annual Symposium on Sea Turtle

Biology and Conservation. NOAA Tech. Memo. NMFS-SEFSC-341. 281 pp.
38

Green, D., and F. Ortiz-Crespo. 1982. Status of sea turtle populations in the central eastern

Pacific. Pages 221-233 in: K.A. Bjorndal (ed.), Biology and Conservation of Sea Turtles.

Smithsonian Inst. Press, Washington, D.C. 583 pp.

Groombridge, B. (compiler). 1982. The IUCN Amphibia-Reptilia Red Data Book, Part I:

Testudines, Crocodylia, Rhyncocephalia. Intl. Union for the Conservation of Nature and

Natural Resources (IUCN), Gland, Switzerland. 426 pp.

Groombridge, B., and R. Luxmoore. 1989. The green turtle and hawksbill (Reptilia: Cheloniidae):

world status, exploitation and trade. CITES Secretariat, Lausanne, Switzerland. 601 pp.

Hays-Brown, C., and W.M. Brown. 1982. Status of sea turtles in the southeastern Pacific:

emphasis on Peru. Pages 235-240 in K.A. Bjorndal (ed.), Biology and Conservation of Sea

Turtles. Smithsonian Inst. Press, Washington, D.C. 583 pp.

Herbst, L.H. Fibropapillomatosis of marine turtles. 1994. Annual Review of Fish Diseases 4:

389-425.

Hurtado, M. 1984. Registros de anidacion de la tortuga negra, Chelonia mydas en las Islas

Galapagos. Bol. Cientifico y Tecnico, Instituto Nacional de la Pesca. Guayaquil, Ecuador.

VI(3):77-106.

Kamezaki, N. and Matsui, M. 1995. Geographic variation in skull morphology of the green turtle,

Chelonia mydas, with a taxonomic discussion. Journal of Herpetology; 29(1): 51-60. 

Karl, S.A., B.W. Bowen, and J.C. Avise. 1992. Global population genetic structure and malemediated gene flow in the green turtle (Chelonia mydas): RFLP analysis of anonymous

nuclear loci. Genetics 131: 163-173.

Linnaeus, C. 1758. Systema naturae per regna tria naturae, secundum classes, ordines, genera,

species, cum characteribus, differentiis, synomymis, locis. Ed. 10, Tomus 1. L. Salvii,

srockholm, Sweden, 823 pp.

Loshbaugh, D. 1993. Dead turtle may have set northern record. Homer News, October 28, 1993.

Lyster, S. 1985. International wildlife law: an analysis of international treaties concerned with the

conservation of wildlife. The Research Centre for International Law, Univ. Cambridge.

Grotius Publications Ltd., Cambridge. 470 pp.

MacFarland, C. 1984. Population ecology of the East Pacific green turtle (Chelonia mydas

agassizi) in the Galapagos Islands. Nat. Geographic Research Reports (16):463-476.

Márquez M., R. 1990. Sea turtles of the world. An annotated and illustrated catalogue of sea

turtle species known to date. FAO Species Catalog, FAO Fisheries Synopsis 11(125):81

pp.
39

McDonald, D., and P. Dutton. 1990. Fibropapillomas on sea turtles in San Diego Bay, California.

Mar. Turtle Newsl. 51:9-10.

McDonald, D., and P. Dutton. 1992. Status of sea turtles in San Diego Bay, 1990 - 1992 Final

Report to the U.S. Fish and Wildlife Services. 16 pp.

McDonald, D., and P. Dutton. 1993. Status of sea turtles in San Diego Bay, 1991-1993 Progress

Report. Report to the San Diego County Dept. of Parks and Recreation, Fish and Wildlife

Advisory Commission. 5 pp.

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South San Diego Bay in relation to the operations of the SDG&E South Bay Power Plant.

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CA.

National Marine Fisheries Service. 1995. Annual report on the biological opinion of June 25,

1994 concerning the take of sea turtles in the Hawaii longline fishery. Unpublished report.

11 pp.

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Thesis, California State University, Northridge. 119 pp.

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Peters, J. 1956. The eggs (turtle) and I. The Biologist (39):21-24.

Pritchard, P.C.H. 1971. Galapagos sea turtles-preliminary findings. J. Herpetol. 5:1-9

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Zamora, R. 1990. Relacion de la humedad del ambiente incubatorio en el avivamiento de

Chelonia agassizii en la playa de Colola, Michoacan, Mexico. UMSNH. Escuela de Biologia

(Tesis Prof.), 43 pp.
40

IV. IMPLEMENTATION SCHEDULE

The Implementation Schedule outlines management and research actions and estimated costs

for the U.S. East Pacific green turtle recovery program, as set forth in this recovery plan. It is a

guide for meeting the objectives discussed in Part II of this plan. This schedule indicates wherever

possible, task priority, task numbers, task descriptions, duration of tasks, the agencies responsible

for committing funds, and lastly, estimated costs. The agencies responsible for committing funds

are not, necessarily, the entities that will actually carry out the tasks. The actions identified in the

implementation schedule, when accomplished, should protect habitat for the species, stabilize the

existing populations, and increase the population sizes and numbers. Monetary needs for all

parties involved are identified to reach this point, whenever feasible.

Priorities in column 3 of the following Implementation Schedule are assigned as follows:

Priority 1 -

An action that must be taken to prevent extinction or to prevent the species from declining

irreversibly in the foreseeable future.

Priority 2 -

An action that must be taken to prevent significant decline in species population/habitat

quality or some other significant negative impact short of extinction.

Priority 3 -

All other actions necessary to provide for full recovery of the species.

KEY to Implementation Table Abbreviations:

CNMI = Commonwealth of the Northern Mariana Islands

COE = U.S. Army Corp of Engineers

DOC = U.S. Department of Commerce

DOI = U.S. Department of Interior

DOS = U.S. Department of State (primarily as a conduit for negotiations and

support for tasks in other political jurisdictions) 

EPA = U.S. Environmental Protection Agency

FSM = Federated States of Micronesia

FWS = U.S. Fish & Wildlife Service

NA = Not applicable

NMFS = National Marine Fisheries Service

NRCS = Natural Resources Conservation Service (Soil Conservation Service)

RMI = Republic of the Marshall Islands

USN = U.S. Navy
A

 ( ) parentheses denote that this task does not necessarily apply to U.S. jurisdiction, but that the task must be addressed if the U.S. populations are to be

restored. Such tasks may require U.S. resource agencies to support recovery tasks in other political jurisdictions.

B 41 The lead agency is listed first.

IMPLEMENTATION SCHEDULE/U.S. PACIFIC

East Pacific Green (Chelonia mydas)

General Task

Categories

Plan Task PriorityA Task

Duration

Agencies

ResponsibleB

Current

Estimated Fiscal Year Costs $K

 

 FY2 FY3 FY4 FY5

Comments/

Notes

1.1 Protect & manage

turtles on nesting

beaches

1.1.1 Eliminate

directed take of

turtles and their eggs

1.1.1.1 Reduce

directed take through

public education &

information

(1) Continuing FWS, NMFS,

DOS

(No documented

nests under U.S.

jurisdiction)

20 20 20 20 20 Support should

be provided for

international

information

exchange forum 

1.1.1.2 Law

enforcement-prevent

illegal exploitation

& harassment

(1) Continuing FWS, US

Customs, NMFS,

DOS

U.S. should

encourage

Mexico to

increase efforts

with the task

1.1 Protect & manage

turtles on nesting

beaches (cont.)

1.1.2 Ensure coastal

construction

activities do not

disrupt nesting &

hatching activities

(2) Continuing COE, FWS,

NMFS, DOS

U.S. should

encourage and

work with

Mexico to

implement this

task

1.1.3 Reduce nest

predation by

domestic & feral

animals

(2) Continuing FWS, DOS U.S. should

encourage

Mexico to

support this

task
IMPLEMENTATION SCHEDULE/U.S. PACIFIC

East Pacific Green (Chelonia mydas)

General Task

Categories

Plan Task PriorityA Task

Duration

Agencies

ResponsibleB

Current

Estimated Fiscal Year Costs $K

 

 FY2 FY3 FY4 FY5

Comments/

Notes

A

 ( ) parentheses denote that this task does not necessarily apply to U.S. jurisdiction, but that the task must be addressed if the U.S. populations are to be

restored. Such tasks may require U.S. resource agencies to support recovery tasks in other political jurisdictions.

B 42 The lead agency is listed first.

1.1 Protect & manage

turtles on nesting

beaches (cont.)

1.1.4 Reduce effects

of artificial lighting

on hatchlings &

nesting females

1.1.4.1 Quantify

effects of artificial

lighting

(3) Continuing FWS, DOS.

1.1.4.2 Implement,

enforce, evaluate

lighting regulations

or other lighting

control measures

(3) NA Currently not

necessary

1.1 Protect & manage

turtles on nesting

beaches (cont)

1.1.5 Collect

biological

information on

nesting populations

1.1.5.1 Monitor

nesting activity,

identify important

nesting beaches,

determine population

trends

(1) Continuing FWS, NMFS,

DOS

50 50 50 50 50 Encourage and

work with

Mexico to

implement this

task. Funds

include Task

1.1.5.2

1.1.5.2 Evaluate

nest success,

implement nestprotection

measures

(1) Continuing
IMPLEMENTATION SCHEDULE/U.S. PACIFIC

East Pacific Green (Chelonia mydas)

General Task

Categories

Plan Task PriorityA Task

Duration

Agencies

ResponsibleB

Current

Estimated Fiscal Year Costs $K

 

 FY2 FY3 FY4 FY5

Comments/

Notes

A

 ( ) parentheses denote that this task does not necessarily apply to U.S. jurisdiction, but that the task must be addressed if the U.S. populations are to be

restored. Such tasks may require U.S. resource agencies to support recovery tasks in other political jurisdictions.

B 43 The lead agency is listed first.

1.1 Protect & manage

turtles on nesting

beaches (cont)

1.1.5 Collect

biological

information on

nesting populations

(cont.)

1.1.5.3 Define

stock boundaries 

1 5 years NMFS, FWS,

DOS

20 20 20 20 20 Includes Tasks

1.1.5.3.1-

1.1.5.3.3

1.1.5.3.1 Identify

stock type for major

nesting beach areas

(1) 5 years

1.1.5.3.2 Determine

nesting beach

origins-juvenile &

subadult populations

1 5 years FWS, NMFS,

DOS

1.1.5.3.3 Determine

genetic relationship

among populations

1 5 years FWS, NMFS

1.2 Protect & manage

nesting habitat

1.2.1. Prevent

degradation due to

erosion-control

measures, jetties &

breakwaters

(3) Continuing COE, FWS,

NMFS, DOS

1.2.2 Eliminate

sand, coral rubble

removal & mining

practices

(3) Continuing
IMPLEMENTATION SCHEDULE/U.S. PACIFIC

East Pacific Green (Chelonia mydas)

General Task

Categories

Plan Task PriorityA Task

Duration

Agencies

ResponsibleB

Current

Estimated Fiscal Year Costs $K

 

 FY2 FY3 FY4 FY5

Comments/

Notes

A

 ( ) parentheses denote that this task does not necessarily apply to U.S. jurisdiction, but that the task must be addressed if the U.S. populations are to be

restored. Such tasks may require U.S. resource agencies to support recovery tasks in other political jurisdictions.

B 44 The lead agency is listed first.

1.2 Protect & manage

nesting habitat

(cont.)

1.2.3 Develop,

evaluate natural

beach-landscaping

guidelines

(3) 4 years FWS, DOS

1.2.4 Ensure

replenishment

projects maintain

quality habitat

(3) Continuing COE, FWS,

NMFS, DOS

Encourage

Mexico to

monitor

situation and

support if

necessary

1.2.5 Implement

non-mechanical

beach cleaning

alternatives

NA NA FWS, DOS

1.2.6 Prevent

vehicular driving on

nesting beaches

(3) Continuing Encourage

Mexico to

monitor

situation and

support if

necessary
IMPLEMENTATION SCHEDULE/U.S. PACIFIC

East Pacific Green (Chelonia mydas)

General Task

Categories

Plan Task PriorityA Task

Duration

Agencies

ResponsibleB

Current

Estimated Fiscal Year Costs $K

 

 FY2 FY3 FY4 FY5

Comments/

Notes

A

 ( ) parentheses denote that this task does not necessarily apply to U.S. jurisdiction, but that the task must be addressed if the U.S. populations are to be

restored. Such tasks may require U.S. resource agencies to support recovery tasks in other political jurisdictions.

B 45 The lead agency is listed first.

2.1 Protect & manage

populations in

marine habitat

2.1.1 Eliminate

directed take of

turtles 

2.1.1.1 Reduce

directed take through

education,

information

1 Continuing NMFS, FWS Encourage and

work with

Mexico to

implement this

task. 

2.1.1.2

Increase/maintain

enforcement

toreduce exploitation

1 Continuing NMFS, USCG,

DOS

Encourage and

work with

Mexico to

support this

task. 

2.1 Protect & manage

populations in

marine habitat

(cont.)

2.1.2 Determine

distribution,

abundance, status 

2.1.2.1 Determine

distribution,

abundance

posthatchlings,

juveniles, adults

1 10 years NMFS, FWS 100 100 100 100 100 Encourage and

work with

Mexico to

support this

task. 

2.1.2.2 Determine

adult migration

routes, internesting

habitats 

2 5 years 100 100 100 100 100 Encourage and

work with

Mexico to

support this

task. 

2.1.2.3 Determine

growth rates,

survivorship, age at

sexual maturity

1 10 years 50 50 50 50 50 Encourage and

work with

Mexico to

support this

task. 
IMPLEMENTATION SCHEDULE/U.S. PACIFIC

East Pacific Green (Chelonia mydas)

General Task

Categories

Plan Task PriorityA Task

Duration

Agencies

ResponsibleB

Current

Estimated Fiscal Year Costs $K

 

 FY2 FY3 FY4 FY5

Comments/

Notes

A

 ( ) parentheses denote that this task does not necessarily apply to U.S. jurisdiction, but that the task must be addressed if the U.S. populations are to be

restored. Such tasks may require U.S. resource agencies to support recovery tasks in other political jurisdictions.

B 46 The lead agency is listed first.

2.1 Protect & manage

populations in

marine habitat

(cont.)

2.1.2 Determine

distribution,

abundance, status

(cont.)

2.1.2.4 Identify

current threats

adults, juveniles on

foraging grounds

1 5 years NMFS, FWS 20 20 20 20 20 Encourage and

work with

Mexico to

support this

task. 

2.1 Protect & manage

populations in

marine habitat

(cont.)

2.1.3 Reduce effects

of entanglement &

ingestion marine

debris

2.1.3.1 Evaluate

extent ingestion of

persistent debris

2 Continuing NMFS, EPA Encourage

Mexico to

support this

task. 

2.1.3.2 Evaluate

effects ingestion

persistent debris

2 5 years Encourage

Mexico to

support this

task. 

2.1.3.3 Reduce,

eliminate persistent

debris

2 Continuing NMFS, EPA,

USCG, FWS

Encourage

Mexico to

support this

task. 
IMPLEMENTATION SCHEDULE/U.S. PACIFIC

East Pacific Green (Chelonia mydas)

General Task

Categories

Plan Task PriorityA Task

Duration

Agencies

ResponsibleB

Current

Estimated Fiscal Year Costs $K

 

 FY2 FY3 FY4 FY5

Comments/

Notes

A

 ( ) parentheses denote that this task does not necessarily apply to U.S. jurisdiction, but that the task must be addressed if the U.S. populations are to be

restored. Such tasks may require U.S. resource agencies to support recovery tasks in other political jurisdictions.

B 47 The lead agency is listed first.

2.1 Protect & manage

populations in

marine habitat

(cont.)

2.1.4 Monitor,

reduce incidental

mortality in

commercial,

recreational fisheries

1 Continuing NMFS 40 40 40 40 40 Encourage and

work with

Mexico to

implement this

task. 

2.1.5 Eliminate

harassment of turtles

at sea

1 3 years 30 30 30 Study in San

Diego Bay

2.1 Protect & manage

populations in

marine habitat

(cont.)

2.1.6 Study the

impact of diseases on

turtles

2.1.6.1 Determine

prevalence of

fibropapillomatosis

in population 

1 5 years NMFS, FWS (as

appropriate to

beach habitat)

50 50 50 50 50 Plus etiology

studies

identified and

funded in green

turtle plans

2.1.6.2 Investigate

parasites and other

infectious agents

3 Contining Encourage

Mexico to

support this

task. 

2.1 Protect & manage

populations in

marine habitat

(cont.)

2.1.7 Maintain

carcass stranding

network

2 Continuing NMFS, U.S.West

Coast, FWS

5 5 5 5 5 All sea turtle

species covered
IMPLEMENTATION SCHEDULE/U.S. PACIFIC

East Pacific Green (Chelonia mydas)

General Task

Categories

Plan Task PriorityA Task

Duration

Agencies

ResponsibleB

Current

Estimated Fiscal Year Costs $K

 

 FY2 FY3 FY4 FY5

Comments/

Notes

A

 ( ) parentheses denote that this task does not necessarily apply to U.S. jurisdiction, but that the task must be addressed if the U.S. populations are to be

restored. Such tasks may require U.S. resource agencies to support recovery tasks in other political jurisdictions.

B 48 The lead agency is listed first.

2.1 Protect & manage

populations in

marine habitat

(cont.)

2.1.8 Centralize

tagging program and

tag-series records

2 Continuing NMFS, FWS 60 60 60 60 60 Encourage

Mexico to

support and

participate - all

species

included

2.2 Protect & manage

marine habitat

2.2.1 Identify

important habitat

1 5 years NMFS Coordinated

with Tasks

2.1.2.1 &

2.1.2.2

2.2.2 Ensure longterm protection1 Continuing Encourage

Mexico to

support task

2.2.3 Assess &

prevent degradation

or destruction of

reefs by boating,

diving activities

(2) Continuing NMFS, FWS,

DOS

Encourage

Mexico to

support task

2.2.4 Prevent

degradation reefs by

pollution

(2) Continuing NMFS, EPA,

USCG, DOS

Encourage

Mexico to

support task
IMPLEMENTATION SCHEDULE/U.S. PACIFIC

East Pacific Green (Chelonia mydas)

General Task

Categories

Plan Task PriorityA Task

Duration

Agencies

ResponsibleB

Current

Estimated Fiscal Year Costs $K

 

 FY2 FY3 FY4 FY5

Comments/

Notes

A

 ( ) parentheses denote that this task does not necessarily apply to U.S. jurisdiction, but that the task must be addressed if the U.S. populations are to be

restored. Such tasks may require U.S. resource agencies to support recovery tasks in other political jurisdictions.

B 49 The lead agency is listed first.

2.2.5 Prevent

degradation or

destruction of reefs

by dredge or disposal

3 Continuing COE, NMFS,

DOS

Encourage

Mexico to

support task

2.2 Protect & manage

marine habitat (cont.)

2.2.6 Prevent

degradation or

destruction by

coastal erosion,

siltation

(2) Continuing FWS, EPA,

NRCS, NMFS,

COE, DOS

Encourage

Mexico to

support task

2.2.7 Prevent

degradation or

destruction of reefs

by blasting

(3) Continuing COE, NMFS,

USN, DOS

Encourage

Mexico to

support task

2.2.8 Prevent

degradation of reefs

by oil transshipment

2 Continuing USCG, NMFS,

EPA

Encourage

Mexico to

support task

2.2.9 Identify other

threats, take action

2 Continuing NMFS, EPA,

USCG

Encourage

Mexico to

support task

3 Ensure proper care

in captivity

3.1 Develop captive

standards

3 2 year NMFS, FWS 35 15
IMPLEMENTATION SCHEDULE/U.S. PACIFIC

East Pacific Green (Chelonia mydas)

General Task

Categories

Plan Task PriorityA Task

Duration

Agencies

ResponsibleB

Current

Estimated Fiscal Year Costs $K

 

 FY2 FY3 FY4 FY5

Comments/

Notes

A

 ( ) parentheses denote that this task does not necessarily apply to U.S. jurisdiction, but that the task must be addressed if the U.S. populations are to be

restored. Such tasks may require U.S. resource agencies to support recovery tasks in other political jurisdictions.

B 50 The lead agency is listed first.

3.2 Catalog captive

turtles for research,

education

3 2 years 10 10

3.3 Designate rehab

facilities

3 1 year 25

4 International

cooperation

4.1 Support 

agreements, conventions, protect in

foreign water

1 Continuing FWS, NMFS,

DOS, DOI, DOC

4.2 CITES

membership,

compliance

1 Continuing

4.3 Develop new

agreements to

protect in foreign

waters

1 Continuing

4.4 Display

information at

airports

2 5 years FWS, NMFS,

U..S.West Coast,

Hawaii, American

Samoa, Guam,

Palau, CNMI,

RMI, FSM,

Unincorp.

Territories

15 15 15 15 Includes all sea

turtle species
A

 ( ) parentheses denote that this task does not necessarily apply to U.S. jurisdiction, but that the task must be addressed if the U.S. populations are to be

restored. Such tasks may require U.S. resource agencies to support recovery tasks in other political jurisdictions.

B 51 The lead agency is listed first.