The Riverhead Foundation: Using necropsies to further awareness of marine conservation issues

Thomas Pratt

● Mission: “to preserve and protect our marine environment through rescue and rehabilitation, research and education.”

● New York State’s only marine mammal and sea turtle rescue and research program.

● Works with cetaceans (whales, dolphins, porpoises), pinnipeds (seals) and sea turtles.

ObjectivesMy objectives in this internship with the Riverhead Foundation were to:

1) Observe direct impacts on sea turtles and know how to prevent it.

2) Observe sex ratios, cause of death, and human impact through necropsies.

3) Gain more insight and knowledge about sea turtle anatomy.

Sea turtles7 species:1. Green sea turtle (Chelonia mydas)2. Loggerhead sea turtle (Caretta caretta)3. Leatherback sea turtle (Dermochelys

coriacea)4. Olive ridley sea turtle (Lepidochelys

olivacea)5. Kemp’s ridley sea turtle (Lepidochelys

kempii)6. Flatback sea turtle (Natador depressus)7. Hawksbill sea turtle (Eretmochelys

imbracata)

Sea turtles7 species:1. Green sea turtle (Chelonia mydas)2. Loggerhead sea turtle (Caretta caretta)3. Leatherback sea turtle (Dermochelys

coriacea)4. Olive ridley sea turtle (Lepidochelys

olivacea)5. Kemp’s ridley sea turtle (Lepidochelys

kempii)6. Flatback sea turtle (Natador depressus)7. Hawksbill sea turtle (Eretmochelys

imbracata)

Sea turtle diet● jellyfish/salps

● Seagrasses and algae

● crustaceans● molluscs● gastropods● sponges

Sea turtle habitats

● pelagic sargassum● coral reefs● mangroves● seagrass beds

When are they found in our area?● Leatherback sea turtles are found in

New York waters all year round; other species are mostly found during the warmer months in the summer for foraging.

● Kemp’s ridley sea turtles are found cold-stunned during the winter from October to March.

(Wallace et al. 2013)

Threats to sea turtles

Human impacts on marine ecosystems have threatened many species that are vulnerable to extinction (Davenport 1997, Halpern et al. 2008, Janzen 1994).● bycatch● fisheries (longlines, gillnets, boat

strikes)● marine pollution and debris● habitat degradation● global climate change

wwf.panda.org

Importance of NGOsNGOs help address conservation issues such as fisheries management, scientific modeling, human impacts, and scientific information and education.

Examples: Greenpeace, Ocean Conservancy, the Marine Conservation Society, and the Worldwide Fund for Nature.

(Groom et al. 2006, Sutherland et al. 2004)

Method of a necropsy

(Wyneken and Witherington 2001)

Findings

Species

Boat/prop

strike

Nematodes/GI tract

inflammation

Broken

bones/missing

appendages Hemorrhages

No

significant

findings Plastic

Dermochelys coriacea 1 0 1 1 1 1

Caretta caretta 3 0 1 0 3 0

Chelonia mydas 0 2 0 1 4 0

Lepidochelys kempii 1 2 0 0 17 0

Boat/propeller strike

Species Male Female Unknown Total number

Dermochelys coriacea 2 1 0 3

Caretta caretta 1 4 1 6

Chelonia mydas 1 6 0 7

Lepidochelys kempii 4 16 0 20

There were 55.6% kemps ridley sea turtles identified represented in the yellow (20), 19.4% green sea turtles represented in the green (7), 16.7% loggerhead sea turtles represented in red (6), and 8.3% leatherback sea turtles represented in blue (3).

Figure 3- Percentage of species

http://www.riverheadfoundation.org/pubfiles/annualreports/2013Report.pdf

http://www.riverheadfoundation.org/pubfiles/annualreports/2013Report.pdf

ImplementationsEndangered Species Act (ESA): 6 populations of sea turtles are threatened; 10 endangered.All listed under CITES appendix I

In the NYS area:Loggerhead- threatenedLeatherback- endangeredGreen- endangeredKemp’s ridley- endangered

What can be done?● TEDs: Turtle Excluder Devices● Circle hooks● Reduce beach lighting● Reduce environmental contamination

www.nmfs.noaa.gov

Current sea turtle research

1. Bycatch identification and management2. Sea turtle diet/GI tract analysis3. Nesting habitat4. Marine pollution and debris

www.nmfs.noaa.gov

ReferencesDavenport, J. (1997). Temperature and the life-history strategies of sea turtles. Journal of thermal biology, 22(6), pp. 479-488.

Groom, M. J., Meffe, G. K., & Carroll, C. R. (2006). Principles of conservation biology (pp. 174-251). Sunderland: Sinauer Associates.

Halpern, B. S., Walbridge, S., Selkoe, K. A., Kappel, C. V., Micheli, F., D'Agrosa, C., ... & Watson, R. (2008). A global map of human impact on marine ecosystems. Science, 319(5865), pp. 948-952.

Janzen, F. J. (1994). Climate change and temperature-dependent sex determination in reptiles. Proceedings of the National Academy of Sciences,91(16), pp. 7487-7490.

Lewison, R. L., Freeman, S. A., & Crowder, L. B. (2004). Quantifying the effects of fisheries on threatened species: the impact of pelagic longlines on loggerhead and leatherback sea turtles. Ecology letters, 7(3), pp. 221-231.

ReferencesDiGiovanni Jr., R., Durham, K., DePerte, A., Ferina, D. The Riverhead Foundation for Marine Research and Preservation Annual Report. (2013). Web. 21 August 2014. <http://www.riverheadfoundation.org/pubfiles/annualreports/2013Report.pdf>

Sutherland, W. J., Pullin, A. S., Dolman, P. M., & Knight, T. M. (2004). The need for evidence-based conservation. Trends in Ecology & Evolution, 19(6), pp. 305-308.

Wallace, B.P., Tiwari, M. & Girondot, M. 2013. Dermochelys coriacea. The IUCN Red List of Threatened Species. Version 2014.2. <www.iucnredlist.org>. Downloaded on 06 August 2014.

Wolke, R. E., & George, A. (1981). Sea turtle necropsy manual. US Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Southeast Fisheries Center, Panama City Laboratory, pp 1-20.

Wyneken, J., & Witherington, D. (2001). The anatomy of sea turtles (p. 172). Southeast Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, US Department of Commerce. pp. 1-52.

Any questions?