SREL Reprint #3538

Global conservation status of turtles and tortoises (Order Testudines)

Anders G.J. Rhodin1,8, Craig B. Stanford2, Peter Paul van Dijk3,8, Carla Eisemberg4,
Luca Luiselli5, Russell A. Mittermeier3, Rick Hudson6, Brian D. Horne7,
Eric V. Goode8, Gerald Kuchling9, Andrew Walde6, Ernst H.W. Baard10,
Kristin H. Berry11, Albert Bertolero12, Torsten E.G. Blanck13, Roger Bour14,
Kurt A. Buhlmann15, Linda J. Cayot16, Sydney Collett4, Andrea Currylow2,
Indraneil Das17, Tomas Diagne18, Joshua R. Ennen19, Germán Forero-Medina20,
Matthew G. Frankel21, Uwe Fritz22, Gerardo García23, J. Whitfield Gibbons15,
Paul M. Gibbons24, Gong Shiping25, Joko Guntoro26, Margaretha D. Hofmeyr27,
John B. Iverson28, A. Ross Kiester8, Michael Lau29, Dwight P. Lawson30,
Jeffrey E. Lovich31, Edward O. Moll32, Vivian P. Páez33, Rosalinda Palomo-Ramos34,
Kalyar Platt35, Steven G. Platt36, Peter C.H. Pritchard37, Hugh R. Quinn38,
Shahriar Caesar Rahman39, Soary Tahafe Randrianjafizanaka40, Jason Schaffer41,
Will Selman42, H. Bradley Shaffer43, Dionysius S.K. Sharma44, Shi Haitao45,
Shailendra Singh46, Ricky Spencer47, Kahleana Stannard4, Sarah Sutcliffe4,
Scott Thomson37,48, and Richard C. Vogt49

1Chelonian Research Foundation, Lunenburg, Massachusetts USA
2University of Southern California, Los Angeles, California USA
3Global Wildlife Conservation, Austin, Texas USA
4Charles Darwin University, Darwin, Northern Territory, Australia
5Institute for Development Ecology Conservation and Cooperation, Rome, Italy
6Turtle Survival Alliance, Charleston, South Carolina USA
7Wildlife Conservation Society, New York, New York USA
8Turtle Conservancy, New York, New York USA
9University of Western Australia, Perth, Western Australia, Australia
10CapeNature, Cape Town, South Africa
11U.S. Geological Survey, Western Ecological Research Center, Riverside, California USA
12Associació Picampall de les Terres de l’Ebre, Amposta, Spain
13Cuora Conservation Center, Deutschlandsberg, Styria, Austria
14Laboratoire des Reptiles et Amphibiens, Muséum National d'Histoire Naturelle, Paris, France
15Savannah River Ecology Laboratory, University of Georgia, Aiken, South Carolina USA
16Galapagos Conservancy, Fairfax, Virginia USA
17Universiti Malaysia Sarawak, Kota Samarahan, Sarawak, Malaysia
18African Chelonian Institute, Ngaparou, Senegal
19Tennessee Aquarium Conservation Institute, Chattanooga, Tennessee USA
20Wildlife Conservation Society and Turtle Survival Alliance, Cali, Colombia
21Surprise Spring Foundation, Prescott, Arizona USA
22Museum für Tierkunde, Senckenberg Dresden, Germany
23Chester Zoo, Upton by Chester, Chester, United Kingdom
24Avian & Exotic Veterinary Care, Portland, Oregon USA
25Guangdong Institute of Applied Biological Resources, Guangzhou, China
26Satucita Foundation, Aceh, Indonesia
27University of the Western Cape, Bellville, South Africa
28Earlham College, Richmond, Indiana USA
29Hong Kong Wetlands Conservation Association, Hong Kong, China
30Oklahoma City Zoo and Botanical Garden, Oklahoma City, Oklahoma USA
31U.S. Geological Survey, Southwest Biological Science Center, Flagstaff, Arizona USA
32Tucson, Arizona USA
33Universidad de Antioquia, Medellín, Colombia
34Universidad Autónoma de Ciudad Juárez, Chihuahua, Mexico
35Turtle Survival Alliance, Yangon, Myanmar
36Wildlife Conservation Society, Yangon, Myanmar
37Chelonian Research Institute, Oviedo, Florida USA
38Turtle Conservation Fund, Kirksville, Missouri USA
39Creative Conservation Alliance, Dhaka, Bangladesh
40Regional Direction of Environment Ecology and Forest and University of Toliara, Madagascar
41James Cook University, Townsville, Queensland, Australia
42Millsaps College, Jackson, Mississippi USA
43La Kretz Center for California Conservation Science, University of California, Los Angeles, California USA
44WWF-Malaysia, Petaling Jaya, Selangor, Malaysia
45Hainan Normal University, Haikou, China
46Turtle Survival Alliance, Lucknow, India
47Western Sydney University, Penrith, New South Wales, Australia
48Museu de Zoologia da Universidade de São Paulo, lpiranga, São Paulo, Brazil
49Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, Brazil

Abstract: We present a review and analysis of the conservation status and International Union for Conservation of Nature (IUCN) threat categories of all 360 currently recognized species of extant and recently extinct turtles and tortoises (Order Testudines). Our analysis is based on the 2018 IUCN Red List status of 251 listed species, augmented by provisional Red List assessments by the IUCN Tortoise and Freshwater Turtle Specialist Group (TFTSG) of 109 currently unlisted species of tortoises and freshwater turtles, as well as re-assessments of several outdated IUCN Red List assessments. Of all recognized species of turtles and tortoises, this combined analysis indicates that 20.0% are Critically Endangered (CR), 35.3% are Critically Endangered or Endangered (CR+EN), and 51.9% are Threatened (CR+EN+Vulnerable). Adjusting for the potential threat levels of Data Deficient (DD) species indicates that 56.3% of all data-sufficient species are Threatened. We calculated percentages of imperiled species and modified Average Threat Levels (ATL; ranging from Least Concern = 1 to Extinct = 8) for various taxonomic and geographic groupings. Proportionally more species in the subfamily Geoemydinae (Asian members of the family Geoemydidae) are imperiled (74.2% CR+EN, 79.0% Threatened, 3.89 ATL) compared to other taxonomic groupings, but the families Podocnemididae, Testudinidae, and Trionychidae and the superfamily Chelonioidea (marine turtles of the families Cheloniidae and Dermochelyidae) also have high percentages of imperiled species and ATLs (42.9-50.0% CR+EN, 73.8-100.0% Threatened, 3.44-4.06 ATL). The subfamily Rhinoclemmydinae (Neotropical turtles of the family Geoemydidae) and the families Kinosternidae and Pelomedusidae have the lowest percentages of imperiled species and ATLs (0%—7.4% CR+EN, 7.4%-13.3% Threatened, 1.65-1.87 ATL). Turtles from Asia have the highest percentages of imperiled species (75.0% CR+EN, 83.0% Threatened, 3.98 ATL), significantly higher than predicted based on the regional species richness, due to much higher levels of exploitation in that geographic region. The family Testudinidae has the highest ATL (4.06) of all Testudines due to the extinction of several species of giant tortoises from Indian and Pacific Ocean islands since 1500 CE. The family Testudinidae also has an ATL higher than all other larger polytypic families (> 5 species) of Reptilia or Amphibia. The order Testudines is, on average, more imperiled than all other larger orders (> 20 species) of Reptilia, Amphibia, Mammalia, or Aves, but has percentages of CR+EN and Threatened species and an ATL (2.96) similar to those of Primates and Caudata (salamanders).

Keywords: IUCN Red List; chelonians; imperiled; endangered; threatened; Average Threat Level; Asia; Geoemydinae; Testudinidae; Reptilia; extinction

SREL Reprint #3538

Rhodin, A. G.J., C. B. Stanford, P. P. Van Dijk, C. Eisemberg, L. Luiselli, R. A. Mittermeier, R. Hudson, B. D. Horne, E. V. Goode, G. Kuchling, A. Walde, E. H.W. Baard, K. H. Berry, A. Bertolero, T. E.G. Blanck, R. Bour, K. A. Buhlmann, L. J. Cayot, S. Collett, A. Currylow, I. Das, T. Diagne, J. R. Ennen, G. Forero-Medina, M. G. Frankel, U. Fritz, G. García, J. W. Gibbons, P. M. Gibbons, G. Shiping, J. Guntoro, M. D. Hofmeyr, J. B. Iverson, A. R. Kiester, M. Lau, D. P. Lawson, J. E. Lovich, E. O. Moll, V. P. Páez, R. Palomo-Ramos, K. Platt, S. G. Platt, P. C.H. Pritchard, H. R. Quinn, S. C. Rahman, S. T. Randrianjafizanaka, J. Schaffer, W. Selman, H. B. Shaffer, D. S.K. Sharma, S. Haitao, S. Singh, R. Spencer, K. Stannard, S. Sutcliffe, S. Thomson, and R. C. Vogt. 2018. Global conservation status of turtles and tortoises (Order Testudines). Chelonian Conservation and Biology 17(2): 135-161.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).