# Alligator Snapping Turtle B iological Status Review Report

March 31, 2011

FLORIDA FISH AND WILDLIFE CONSERVATION COMMISSION

620 South Meridian Street Tallahassee, Florida 32399

- 1600Alligator Snapping Turtle Biological Status Review Report 2 

### Biological Status Review

for the Alligator Snapping Turtle
( Macrochelys temminckii ) March 31, 2011

EXECUTIVE SUMMARY

The Florida Fish and Wildlife Conservation Commission (FWC) directed staff to evaluate species listed as Threatened or Species of Special Concern as of November 8

, 2010 that

had no t undergone a status review in the past decade . Public information on the s tatus of the

a lligator s napping t urtle was sought from September 17 through November 1, 2010. The 5

- member biological revie w group (BRG) met on November 9

- 10 , 2010. Group members were

Bill Turner (FWC lead), Chris Lechowicz ( Sanibel

- Captiva Conservation Foundation ), Peter Meylan (Eckerd College), Paul Moler (independent consultant ) and Travis Thomas (FWC) (Appendix 1) . In accordance with rule 68A

- 27.0012

, F lorida A dministrative C ode (F.A.C.) , the BRG was charged with evaluating the biologic al status of the a lligator s napping t urtle using

criteria included in definitions in 68A

- 27.001 , F.A.C.

, and following protocols in the Guidelines for Application of the IUCN Red List Criteria at Regional Levels (Version 3.0) and Guidelines for Using the I UCN Red List Categories and Criteria (Version 8.1)

. Please visit http://myfwc.com/wildlifehabitats/imperiled/listing

- action

- petitions/ to view the listing process

rule and the criteria found in the definitions.

In late 2010, staff developed the initial draft of this report which included BRG findings and a preliminary listing recommendation from staff. The draft was sent out for peer review and

the reviewers ’ input has b een incorporated to create this final report. The draft report, peer reviews, and information received from the public are available as supplemental materials at http://myfwc.com/wildlifehabitats/imperiled/biological

- status/

.

The BRG concluded from the biological assessment that the a lligator snapping turtle met
criteri on B2ab (iii) ; c iting severe fragmentation of the population as part of the criterion. This is

de scribed in the guidelines for listing as “ a taxon can be considered to be severely fragmented if most (>50%) of its total area of occupancy is in habitat patches that are (1) smaller than would be required to support a viable population, and (2) separated from other habitat patches by a large distance.” After the review was conducted, staff further evaluated the concept of “severely fragmented” and believes that it does not apply to the alligator snapping turtle. When conducting the Regional Assessment

, t he BRG discussed that should there be a catastrophic event in Florida that eliminated populations of alligator snapping turtles, there could be a rescue effect from turtles outside Florida. In these situations, the listing guidelines consider downgrading the initial listing finding to a less imperiled status

. Taking into consideration both of these factors, staff

recommends not listing the alligator snapping turtle as T hreatened and to remove it from the Species of Special Concern list

.

This work was supported by a Conserve Wildlife Tag grant from the Wildlife Foundation

of Florida. FWC staff gratefully acknowledges the assistance of the biologi cal review groupAlligator Snapping Turtle Biological Status Review Report 3 members and peer reviewers . Staff thanks Dr. Dale Jackson for serving as a data compiler o n the species and draft ing the Biological Information section of this report

. BIOLOGICAL INFORMATION

Taxonomic Classification

– The alligator snapping turtle ( Macrochelys temminckii ) ( Harlan 18 3 5) is universally recognized as a full species with no close living relatives (Ewert et al. 2006)

.

Life History and Habitat R e quirements

– Life history and habitat of the alligator snapping turtle have been summarized by Ewert et al. (2006), Pritchard (2006), and Ernst and Lovich (2009). In Florida, the species is restricted to rivers and associated permanent freshwater habitats. The latter include floodplain swamp forests characterized by tannic or turbid waters, bald cypres s and tupelo, and numerous channels and deep holes (Ewert and Jackson 1994). The only lakes supporting the species are either impounded sections of large rivers (Lake Seminole: Apalachicola, Lake Talquin: Ochlockonee) or natural lakes with at least occasi onal connection to a river (e.g., Lake Iamonia, Leon County). Alligator snapping turtle s also make use of surprisingly small streams, such as the seepage streams on Eglin Air Force Base. A few adults have been taken from brackish water habitats (e.g., Oc hlockonee Bay, Franklin County), with some individuals even supporting barnacles, but movements into salt water are extremely rare (Ewert et al. 2006, Pritchard 2006). The alligator snapping turtle is by far the largest North

American freshwater turtle. Although both sexes achieve large body size, the oft

- pictured behemoths (up to 250 lbs

, 29 inch carapace length [CL]) are all males, which grow considerably larger than females (maximum ca. 62 lbs

, 22 inches CL) (Ewert et al. 2006, Pritchard 2006).

B oth s exes require at least 15 , and probably 20 years to mature ( Sloan et al. 1996, Tucker and Sloan 1997, Reed et al. 2002) . Lifespan in the wild is unknown, but captives have lived in excess of 75 years (Snider and Bowler, 1992). Based on these data, a conse rvative estimate of average age of parents (generation time) is 30

- 40 years. Reed et al. (2002) estimated generation time at 49 years. All studies (e.g., Allen and Neill 1950, Dobie 1971, Ewert and Jackson 1994) indicate that females produce but one clut ch per year, and some may occasionally skip years (Dobie 1971). The nesting season is correspondingly short, extending from late April to mid

May in Panhandle Florida (Ewert 1976

, Ewert and Jackson 1994). Nests are constructed in sandy soils when availab le, normally within 20 m of water but sometimes as far as 200 m.

Natural berms 2

- 3 m high are favored along the lower Apalachicola River, but these have been supplemented and in part replaced by man

- made deposits of sandy dredged spoil, which tend to prod uce more female hatchlings as a consequence of temperature

- dependent sex determination (Ewert and Jackson 1994, Ewert et al. 1994). Clutch sizes along the lower Apalachicola River, the best studied site, average ca. 36 eggs (range 17

- 52). Most eggs there hatch in the second half of August after 100

- 110 days of incubation, followed within a few weeks by hatchling emergence (Ewert and Jackson 1994). Although little studied in Florida, the diet of the alligator snapping turtle across its range is rather bro ad and chiefly carnivorous, although plant matter seems also to be important (Ewert et al. 2006). Juveniles feed predominantly upon small fish, but the diet broadens with age and growth. While fish remain important, crustaceans, mollusks (both bivalve an d gastropod: Allen and Neill 1950), aquatic salamanders, water birds, mammals, and other turtles all become significant components.Alligator Snapping Turtle Biological Status Review Report 4 Population Status and Trend

– Based on past extent of harvest ( Ewert et al. 2006, Pritchard 2006), there is little doubt th at the alligator snapping turtle once was extremely numerous and accounted for substantial biomass throughout many Southeastern riverine systems

, including those in Florida

. Although rigorous data documenting the century or more of human

take do not exist, there is equally little doubt that extensive harvest, both commercial and personal, depleted populations in many rivers. Typically, after periods of heavy effort, declining yields forced harvesters to move on to other sites (Pritchard 2006). This is not unexpected given the long generation time of alligator snapping turtle s and the normally low rate s of recruitment of virtually all turtles. Beginning in 1973 , enactment of a series of protective rules by FWC (then

the Florida Game and Fresh Water F ish Commission [ GFC ] ) reduced the species’ rate of decline in Florida, although harvest (legal and illegal) still occurred. FWC rule changes in 2009 prohibited take of all snapping turtles and ended legal harvest. Whether the statewide population

has stab ilized or begun to increase is undetermined , although some Florida rivers support healthy populations (Ewert et al. 2006)

.

Geographic Range and Distribution

– The alligator snapping turtle occupies Gulf Coast drainages from Florida to Texas and northwar d to Illinois; in Florida, the species inhabits

most

, if not all

, of the larger drainages in the Panhandle and Big Bend regions, from the Escambia River to the Suwannee River (Ewert et al. 2006, Pritchard 2006 )

.

Quantitative Analyses

– The principal attem pt at modeling population demography of

the alligator snapping turtle and evaluating population effects of changes in life history parameters is that of Reed et al. (2002). They concluded that an annual survival rate of 98% for adult females was necessary for population stability, that any lesser rate would lead to long

- term population decline and eventual extirpation, and that even su ccessful efforts to increase egg and juvenile survival would be unlikely to compensate for continued loss of adult females. While the model may have underestimated the rate s of nest and/or juvenile survival in the wild, which might lead to an overestimate of necessary female survival rate (Ewert et al. 2006), the conclusion that long

- term population viability requires very hi gh rates of female survival is

sound.

BIOLOGICAL STATUS ASSESSMENT

Threats

– Not surprisingly given its size and catchability, the alligator snapping turtle has a long history of both commercial and personal harvest for meat throughout its range,

includi ng in Florida (Dobie 1971, Sloan and Lovich 1995, Reed et al. 2002, Ewert et al. 2006, Pritchard 2006). There is little doubt that this suppressed populations locally and regionally. Beginning in the 1970s, rules enacted by the GFC to limit take likely s lowed the rate of mortality in Florida, though both legal and illegal harvest still occurred. Legal take of alligator snapping turtles was prohibited by rule changes enacted by FWC in 2009. However, it may be years or decades before the negative impacts of long

- term harvest are fully reversed. Even in the absence of legal harvest, there remains a problem of bycatch mortality on lines set for fish, especially catfish. These include both trot lines (long lines of submerged baited hooks) and bush lines (s ingle hooks suspended from tree branches) (Ewert et al. 2006, Pritchard 2006). The latter may be more widely used in rivers and hence likely present a greater problem for the alligator snapping turtle . Because rivers tend to be relatively stable and pers istent systems compared toAlligator Snapping Turtle Biological Status Review Report 5 most Florida habitats, outright habitat destruction is not a major threat to this turtle. Nonetheless,

various human

- generated insults to the integrity of lotic systems, including their floodplains, can

and do affect Florida’s r iverine turtles (Jackson 2005). Chemical pollution (from industries such as pulp mills, and waste products from cities and agricultural activities, including those in Alabama and Georgia) always poses a potential threat to all riverine fauna, though even a major spill along one Panhandle river would not endanger the species’ statewide population (Ewert et al. 2006). Other than the industrially degraded Fenholloway River in Taylor County, which once may have supported the alligator snapping turtle but pres umably no longer does (Jackson 1999), the Escambia River in western Florida is probably the most polluted (from pulp mill effluent) yet still retains the species (Moler 1996, Jackson 2005). Siltation from road crossings, borrow pits, or other situations p robably can reduce the suitability of smaller streams, such as the clear seepage streams on Eglin Air Force Base, that the species utilizes. Although both major impoundments (by dams designed to provide electricity, flood protection, and recreation) withi n the alligator snapping turtle ’s Florida range (Lake Talquin: Ochlockonee River, Lake Seminole: Apalachicola River) still support the species, long

- term impacts of microhabitat changes and shoreline development are unstudied but potentially negative (Ewer t et al. 2006). A third impoundment has been proposed for the Yellow River but would require substantial review by regulatory agencies to be considered further. As for all turtles, predation, particularly by raccoons, accounts for the loss of a majority of alligator snapping turtle eggs (about 2/3 along the lower Apalachicola River). Additional potential predators include wild hogs and imported fire ants. Nest flooding following very heavy regional rains also destroys entire clutches in some years (Ewer t and Jackson 1994).

Population Assessment

– Findings from the BRG are included in the Biological Status

Review Information Findings tables. The BRG concluded from the biological assessment that

the alligator snapping turtle met criteri on B2ab ( iii); citing severe fragmentation of the population (B2a) as part of the criterion. When conducting the Regional Assessment, the BRG discussed that, should there be a catastrophic event in Florida that eliminated populations of alligator snapping turtles, there could be a rescue effect from turtles outside Florida. In these situations, the listing guidelines consider downgrading the initial listing finding to a less imperiled status.

After a careful review of the information with regards to sub

- criterion B2ab, staff

believes that the BRG misinterpreted guidance on fragmentation which led to a misapplication of

the B2a sub

- criterion. Staff believes the alligator snapping turtle is not severely fragmented under the definition used in the biological status review process.

The BRG and staff both referred to the Version 8.1 of the IUCN Guidelines for Using the IUCN Red List Categories and Criteria for guidance on fragmentation. Under the section entitled “4.8 Severely fragmented (Criterion B)

, ” fragmentatio n is defined as “a situation in

which increased extinction risks to the taxon result from the fact that most of its individuals are found in small relatively isolated subpopulations.” Further guidance is given that, “a taxon can

be considered to be severe ly fragmented if most (>50%) of its total area of occupancy is in habitat patches that are (1) smaller than would be required to support a viable population, and (2) separated from other habitat patches by a large distance.” It is implied that the distanc e is large relative to the species’ ability to cover the distance. The BRG considered alligator snapping turtles “severely fragmented” because alligator snapping turtles are not known to frequentlyAlligator Snapping Turtle Biological Status Review Report 6 move between the rivers where their populations occur, wh ich considers the second part of the guidance. While this may be valid, the first part of the fragmentation guidance is not supported by current data. There is no indication that more than 50% of the alligator snapping turtles are in habitat patches smal ler than would be required to support viable populations. If non

- viable alligator snapping turtle populations were in habitat patches so far apart that the snappers could not move from one to another, then alligator snapping turtles would indeed be at ris k of

extinction. This is not the case. Within most rivers there seem to be viable populations of alligator snapping turtles. For this reason, staff does not consider alligator snapping turtle populations severely fragmented and believe th e B2a sub

- crite rion is not met.

LISTING RECOMMENDATION

Staff recommends not listing the alligator snapping turtle as a T hreatened species and to

remove it from the Species of Special Concern list

.

SUMMARY OF THE INDEPENDENT REVIEW

John Jensen (Georgia Department of Natural Resources) , Kenneth P. Way (Florida State University) and Joseph Apodaca (Florida State University) reviewed this document. Although

all three peer reviewers support ed the findings of the BRG, one did not support the staff

recommendation to no t list the alligator snapping turtle as threatened . Th is reviewer expressed that the alligator snapping turtle populations in Florida were fragmented and doubted that alligator snapping turtles from outsi de of Florida could repopulate some Florida river sy stems

.

One reviewer also pointed out that the Suwannee River clade of alligator snapping turtles is genetically distinctive from the other alligator snapping turtles in Florida and as such may warrant protection. This issue was discussed in the BRG

. A lthough the Suwannee River clade is morphologically and genetic ally distinct ive from other populations of alligator snapping turtles,

the taxonomic status of this clade is uncertain

. Until the taxonomy of the Suwannee River clade

is determined, the turtles in this clade will be given the same consideration s as other alligator snapping turtles in Florida

. The reviewer recommend ed that the population receive further study.

A reviewer stated that there has been heavy harvest pressure on alligator snapping turtles, although the species has been protected by FWC rules since the 1970s. He also stated the species is easily harvested at high rates. This does not seem to be the case. Although alligator snapping tur tles are caught on trot lines, they are not caught at a high rate compared to other turtles probably due to t heir low density in the habitat . B ecause of FWC rules

, alligator snapping

turtle harvest has no t be en commercialized in F lorida

.

Full text of the peer reviews is availa ble at myFWC.com.Alligator Snapping Turtle Biological Status Review Report 7 LITERATURE CITED

Allen, E. R., and W. T. Neill. 1950. The alligator snapping turtle Macrochelys

temminckii in Florida. Ross Allen's Reptile Institute Special Publication 4:1

- 15.

Dobie, J. L. 1971. Reproduction and growth in the alligator snapping turtle Macroclemys

temminckii (Troost). Copeia 1971:645

- 658.

Ernst, C. H., and J. E. Lovich. 2009. Turtles of the United States and Canada . S econd edition. The Johns Hopkins University Press, Baltimore, Maryland, USA

. 827pp.

Ewert , M. A., and D. R. Jackson. 1994. Nesting ecology of the alligator snapping turtle ( Macroclemys temminckii ) alo ng the lower Apalachicola River, Florida. Florida Game and Freshwater Fish Commission, Nongame Wildlife Program Report NC89

- 020, Tallahassee, Flor ida, 45 pp.

Ewert

, M. A

., D. R. Jackson, and P. E. Moler. 2006. Macrochelys temminckii

– alligator snapping turtle

. Pages 58

– 71 in P. A. Meylan, editor

. Biology and c onservation of

Florida t urtles. Chel onian Research Monographs No. 3.

Ewert, M. A

., D. R. Jackson, and C. E. Nelson

. 1994. Patterns of temperature

- dependent sex

determination in turtles. Journal of Experimental Zoology 270

- 3

- 15.

Florida Natural Areas Inventory. Tallahassee, Florida, USA. [contacts: via the Internet at www.fnai.org , or telephone 850

- 224

- 8207]

Harlan, R. 1835. Genera of North American Reptilia and a synopsis of the species. Pages 84

– 160 in Medical and Physical Researches. Lydia R. Bailey, Philadelphia, Pennsylvania,

USA.

Jackso n, D. R. 1999. Survey of an important distributional "gap" in the Florida range of the river cooter and other freshwater turtles. Final Report to Nongame Wildlife Program,

Florida Game and Fresh Water Fish Commission.

Jackson, D. R. 2005. Florida rivers and turtles: an interdependence. Pages 163

– 168 in W. E. Meshaka, Jr., and K. J. Babbitt, editors. Amphibians and reptiles: status and conservation

in Florida. Krieger Publishing Company, Malabar, Florida, USA. 318p p.

Moler, P. E. 1996. Alligator snapping turtle distribution and relative abundance. Florida Game and Freshwater Fish Commission, Final Report 7544. 13pp.

Pritchard, P. C. H. 2006. The alligator snapping turtle : biology and conservation. S econd

ed ition. Krieger Publishing Company, Malabar, Florida , USA

. 140pp.

Reed, R. N., J. D. Congdon, and J. W. Gibbons. 2002. The alligator snapping turtle
[ Macroclemys (Macrochelys) temminckii ]: a review of ecology, life history, andAlligator Snapping Turtle Biological Status Review Report 8 conservation, with demog raphic analyses of the sustainability of take from wild populations. Report to: Division of Scientific Authority, United States Fish and Wildlife Service. [available on the Internet at http://www.uga.edu/srelherp ]

Sloan, K. N. , K. A. Buhlmann , and J. E. Lovich. 1996. Stomach contents of commercially

harvested adult alligator snapping turtle s, Macroclemys temminckii . Chelonian Conservation and Biology 2:96

- 99.

Sloan, K. N. , and J. E. Lovich. 1995. Exploitation of the alligator snapping turtle

, Macroclemys temminckii, in Louisiana: a case study. Chelonian Conservation and Biology 1:221

- 222.

Snider, A. T., and J. K. Bowler. 1992. Longevity of reptiles and amphibians in North American

colle ctions. Second edition. Society for the Study of Amphibians and Reptiles Herpetological Circular 21:1

- 40.

Tucker, A. D., and K. N. Sloan. 1997. Grow th and reproductive estimates from alligator snapping turtle s, Macroclemys temminckii , taken by commercial harvest in Louisiana. Chelonian Conservation and Biology 2 : 587

- 592.Alligator Snapping Turtle Biological Status Review Report 9 

### Biological Status Review Information
Findings Species/taxon: Alligator Snappi ng Turtle

Date: 11/ 10/1 0

Assessors: Chris Lechowicz, Peter Meylan, Paul Moler,

Bill Turner and Travis Thomas

Generation length: 30

- 40 years (ca. 35 years)

Criterion/Listing Measure Data/Information Data Type* Sub

- Criterion

Met? References

*Data Types

- observed (O), estimated (E), inferred (I), suspected (S), or projected (P). Sub

- Criterion met

- yes (Y) or no (N).
(A) Population Size Reduction , ANY of
(a)1. An observed, estimated, inferred or suspected population size reduction of at least 50% over the last 10 years or 3 generations, whichever is longer, where the causes of the reduction are clearly reversible and understood

and ceased 1 Has been harvest throughout the past 90 years however

due to histori c harvest pressures and existing sampling data it is unlikely that there has been a 50% decline

. I N Ewert et al. 2006, Pritchard

2006

(a)2. An observed, estimated, inferred or suspected population size reduction of at least 30% over the last 10

years or 3 generations, whichever is longer, where the reduction or its causes may not have ceased or may not be understood or may not be reversible 1 We suspect that there has not been a 30% decline although there was historic and continuing harvest

. S N Ewert et al. 2006, Pritchard

2006

(a)3. A population size reduction of at least 30% projected or suspected to be met within the next 10 years or 3 generations, whichever is longer (up to a maximum of 100 years) 1 Projections for sea level rise during the next 90 years may increase the salinity of the waterways which could result in habitat loss and reduction of the population

, but group is uncertain that the reduction would be at

least 30%

. S N

(a)4. An observed, estimated, inferred, projected or suspected population size reduction of at least 30% over any 10 year or 3 generation period, whichever is longer (up to a maximum of 100 years in the future), where the time period must include both the past and the future, and where the

reduction or its c auses may not have ceased or may not be understood or may not be reversible. 1 We suspect that there has not been a 30% decline although there was historic and continuing harvest and potential for additional decline due to projected sea

level rise

. S N Ewer t et al. 2006, Pritchard

2006

1 based on (and specifying) any of the following: (a) direct observation; (b) an index of abundance appropriate to the taxon; ( c) a decline in area of occupancy, extent of occurrence and/or quality of habitat; (d) actual or potential levels of exploitation; (e) the effects of introduced taxa, hybridization, pathogens, pollutants, competitors or parasites.

(B) Geographic Range , EITHER
(b)1. Extent of occurrence < 20,000 km 2 (7,722 mi 2 ) OR 46,000 km 2 E N D. Jackson GIS polygon
(b)2. Area of occupancy < 2,000 km 2 (772 mi 2 ) 440 km 2 E Y D. Jackson GIS polygons
AND at least 2 of the following:Alligator Snapping Turtle Biological Status Review Report 10 a. Severely fragmented or exist in ≤ 10 locations Occupies 12 river drainages in FL

- the group thought that the population is severely fragmented because the rivers isolated by drainage basin and reduced terrestrial mobility across drainage basins, but individual river basin populations are viable I Y Ewert et al. 2006, FL Natural Areas Inventory (FNAI)

b. Continuing decline, observed, inferred or projected in any of the following: (i) extent of occurrence; (ii) area of occupancy; (iii) area, extent, and/or quality of habitat; (iv) number of locations or subpopulations; (v) number

of mature individuals Projections for sea level rise duri ng the next 90 years may increase the salinity of the waterways which could result in habitat loss and a corresponding decline.

F uture water quality decline and increased human

demand for the water could also result in decline of the population

. I /S Y

c. Extreme fluctuations in any of the following: (i) extent of occurrence; (ii) area of occupancy; (iii) number of locations or subpopulations; (iv) number of mature

individuals No; extreme fluctuations unlikely in long

- lived species; rivers relatively sta ble. S N

(C) Population Size and Trend
Population size estimate to number fewer than 10,000

mature individuals AND EITHER The alligator snapping turtle has a very restricted area of occupancy, 1 2 drainages. Travis Thomas (BSR group member) estimates 6 turtles per km from his research. Using this values multiplied by length of the rivers gives an estimate of 3000 turtles for the S uwannee and

S anta F e Rivers (where Thomas is conducting research). Group suspects there are over 10

, 000 alligator snapping

turtles in Florida S N Moler 1996, Ewert et al.

2006 offer catch

- per

- unit

effort data, but no population

numbers.

(c)1. An estimated continuing decline of at least 10% in 10 years or 3 generations, whichever is longer (up to a

maximum of 100 years in the future) OR Defer to Cc2.

(c)2. A continuing decline, observed, projected, or inferred

in numbers of mature individuals AND at least one of the following: With strong enforcement of 2009 FWC rules prohibiting take, population likely to grow. P N

a. Population structure in the form of EITHER No suitable quantitative population size data but likely >1000 in Apalachicola and Suwannee drainages. S N Ewert et al. 2006
(i) No subpopulation estimated to contain more

than 1000 mature individuals; OR
(ii) All mature individuals are in one subpopulation No; occurs in at least 11 independent drainages. I N Ewert et al. 2006, FL Natural Areas Inventory (FNAI)

b. Extreme fluctuations in number of mature

individuals No; extreme fluctuations unlikely in long

- lived species; rivers provide relatively stable habitat. S N Jackson 2005, Ewert et al.

2006

(D) Population Very Small or Restricted , EITHER

(d)1. Population estimated to number fewer than 1,000

mature individuals; OR Few quantitative data available, but Moler's trapping survey and Ewert/Jackson nesting study on Apalachicola River suggest >1000. S N Moler 1996, Ewert et al. 2006, FL Natural Areas Inventory (FNAI)Alligator Snapping Turtle Biological Status Review Report 11 (d)2. Population with a very restricted area of occupancy (typically less than 20 km 2 [8 mi 2 ]) or number of locations (typically 5 or fewer) such that it is prone to the effects of

human activities or stochastic events within a short time period in an uncertain future Both estimated area of o ccupancy (440 km2) and number of inhabited rivers (1 @ ; each river is at least one location) exceed this. S N Ewert et al. 2006, FL Natural Areas Inventory (FNAI), D. Jackson GIS polygons

(E) Quantitative Analyses
e1. Showing the probability of extinction in the wild is at least 10% within 100 years Uncertain; Reed et al. (2002) model assumptions questionable , but suggests possible with even moderate

take

. P N Reed et al. 2002

Initial Finding ( Meets at least one of the criteria /sub

- criteria OR Does

not meet any of the criteria /sub

- criteria ) Reason ( which criteria/sub

- criteria are met )

meets one criterion B2ab (iii)

Is species/taxon endemic to Florida? (Y/N) N

If Yes, your initial finding is your final finding. Copy the initial finding and reason to the final finding space below. If No, complete the regional assessment sheet and copy the final finding from that sheet to the space below.

Final Finding ( Meets at least one of the criteria /sub

- criteria OR Does

not meet any of the criteria /sub

- criteria ) Reason ( which criteria/sub

- criteria are met )

meets one criterion B2ab (iii)Alligator Snapping Turtle Biological Status Review Report 12 Regional Assessment

1 

### Biological Status Review Information
Regional Assessment Species/taxon: Alligator Snapping Turtle

2 Date: 11/ 10/1 0

3 Assessors: Chris Lechowicz, Peter Meylan, Paul Moler,

4 Bill Turner and Travis Thomas

5

6

7

8 Initial finding

9

10 2a. Is the species/taxon a non

- breeding visitor? (Y/N/DK). If 2a is YES, go to line 18. If 2a is NO or DO NOT KNOW, go to line 11. N

11 2b. Does the Florida population experience any significant immigration of propagules capable of reproducing in Florida? (Y/N/DK). If 2b is YES, go to line 12. If 2b is NO or DO NOT KNOW, go to line 17. Y

12 2c. Is the immigration expected to decrease? (Y/N/DK). If 2c is YES or DO NOT KNOW, go to line 13. If 2c is NO go to line 16. N

13 2d. Is the regional population a sink? (Y/N/DK). If 2d is YES, go to line 14. If 2d is NO or DO NOT KNOW, go to line 15.

14 If 2d is YES

- Upgrade from initial finding (more imperiled)

15 If 2d is NO or DO NOT KNOW

- No change from initial finding

16 If 2c is NO or DO NOT KNOW

- Downgrade from initial finding (less imperiled) Downgrade

17 If 2b is NO or DO NOT KNOW

- No change from initial finding

18 2e. Are the conditions outside Florida deteriorating? (Y/N/DK). If 2e is YES or DO NOT KNOW, go to line 24. If 2e is NO go to line 19.

19 2f. Are the conditions within Florida deteriorating? (Y/N/DK). If 2f is YES or DO NOT KNOW, go to line 23. If 2f is NO, go to line 20.

20 2g. Can the breeding population rescue the Florida population should it decline? (Y/N/DK). If 2g is YES, go to line 21. If 2g is NO or DO NOT KNOW, go to line 22.

21 If 2g is YES

- Downgrade from initial finding (less imperiled)

22 If 2g is NO or DO NOT KNOW

- No change from initial finding

23 If 2f is YES or DO NOT KNOW

- No change from initial finding

24 If 2e is YES or DO NOT KNOW

- No change from initial finding

25

26 Final findingAlligator Snapping Turtle Biological Status Review Report 13 Additional notes

. Calculation of generation time presented at the BSR group meeting

Generation length is defined as the average age of parents of the current cohort, which is greater than the age at first breeding and less than the age of the oldest breeding individual. W e estimate

g eneration l ength for the alligator snapping turtle as follows . Dobie (1971) e stimated both sexes

mature in LA in 11

- 13 y ea rs (no data for FL) but noted a two

- thirds decline in growth rate by ages 16

- 35; this suggests slightly later maturation, probably closer to 15

- 20 . Lifespan in the wild

is unknown (Ewert et al. 2006)

, but individuals may live >75 years in captivity (Snide r and Bowler, 1992). We therefore conservatively estimate average age of parents at 30

- 40 y ea rs and recognize that this is more likely to be an underestimate than overestimate . Reed et al. (2002)

estimated a generation length of 49 years.Alligator Snapping Turtle Biological Status Review Report 14 APPENDIX 1 . Brief biographies of the Alligator snapping turtle Biological Review Group

members.

Chris Lechowicz is the Interim Director of the Wildlife Habitat Management Program and staff herpetologist at the Sanibel

- Captiva Conservation Foundation wher e he has worked since 2002. He has a B.S. in Zoology and Computer Science from Southern Illinois University at Carbondale and will complete his M.S. in Environmental Science from Florida Gulf Coast University in

2010. Chris’s focus is on riverine turtles w ith a specialty on the Genus Graptemys. Chris is a member of the IUCN/SCC Tortoise and Freshwater Turtle Specialists Group as well as a board

member of the Florida Turtle Conservation Trust.

Dr. Peter A. Meylan received his Ph.D. from the University of Florida. He is a Professor of Biology at Eckerd College in Saint Petersburg, FL. His research interests include the evolutionary history, ecology, and conservation biology of amphibians and reptiles, especially

turtles. Current research includes 2 sea tu rtle projects: an investigation of the ecology and migrations of sea turtles of Bocas del Toro Province, Panama (funded by the Wildlife Conservation Society) and the Bermuda Turtle Project, which is a cooperative project with the Bermuda Aquarium and the C aribbean Conservation Corporation (as well as continuing to work with Florida freshwater turtles with the Eckerd Herpetology Club on the Rainbow River). He has many scientific articles on turtles and is the editor of a book on the biology and conservation

of Florida turtles.

P aul E. Moler received his M.S. in Zoology from the University of Florida in 1970 and his B.A. in Biology from Emory University in 1967. He re tired in 2006 after working for 29 years as a herpetologist with FWC, including serving as administrator of the Reptile and Amphibian

Subsection of the Wildlife Research Section . He has conducted research on the systematics, ecology, reproduction, genetics, and conservation biology of a variety of herpetofaunal species in

Florida , with primary emphasis on the biology and management of endangered and threatened species

. He served as Chair for the Florida Committee on Rare and Endangered Plants and

Animals in 1992

– 94, Chair of the Committee on Amphibians and Reptiles since 1986, and editor

of the 1992 volume on amphibians and reptiles. Paul has more than 90 publications on amphibians and reptiles.

Travis Thomas received a Bachelor’s Degree in 2008 from the University of Florida in Natural Resources Conservation. He is currently pursuing a Maste rs Degree in Wildlife Ecology and Conversation under the supervision of Dr. Perran Ross. His primary research focuses on the ecology and management of fauna in riparian systems. He was hired by FWC in 2008, and he has worked on numerous projects concernin g reptile and amphibian ecology. He worked for 3 years in the Herpetology Dept. under Dr. Kenneth Krysko at the Florida Museum of Natural History. He has spent time as a volunteer on numerous projects in Kenya, Africa, under the supervision of Leigh Eccle stone and the Kenyan Wildlife Service. He has published several notes on the ecology and distribution of reptiles and is currently a co

- author on a study of the ecology of M. temminckii in O’Leno State Park as well as the primary author on a study of the

m orphology of M. temminckii.Alligator Snapping Turtle Biological Status Review Report 15 William M. Turner received his B.S. from Erskine College and M .S. in Biology from the University of South Alabama. From 2003 to 2007, he was the Herpetological Coordinator for the Wyoming Game and Fish Department. In Wyoming, he conducted statewide surveys for amphibians and reptiles, focusing on emerging amphibian diseases and the impacts of resource development nat ive reptiles. Since 2007, he has been the Herp Taxa Coordinator for FWC in the Division of Habitat and Species Conservation. He has conducted research on native amphibians and reptiles in Florida, Alabama and Wyoming that has resulted in several published papers and

reports.Alligator Snapping Turtle Biological Status Review Report 16 APPENDIX 2

. Summary of letters and emails received during the s olicitation of information from the public period of September 17, 2010 through November 1, 2010.

A comment was received via email from Jeff Preacher, who is a recr eational cat fish fisherman in the Milton, FL area. He has captured alligator snapping turtle s while fishing on the Blackwater, Yellow and Escambia Rivers u s ing trot lines and bush hooks. He stated that alligator snapping turtle s seemed as abundant now as 3 0 years ago. He claimed from observation of captive and wild turtles that alligator snapping turtle s grow more quickly than most suppose . He felt that large ones 90+ lbs in weight were only in their 20s. His data are based on aging turtles

with the annular rings on their scutes (scales on their dorsal shells). He felt that alligator snapping turtle s were able to endure “man’s encroachment” into their habitat because they often

remained unseen. He stated that the main threat to alligator snapping turtle s is commercialization and that the current turtle rules (no take of alligator snapping turtle s) are too restrictive. He felt

that the alligator snapping turtle s could be harvested with a permit and stated that he would gladly participate in such a permitting system.