Herpetology Notes, volume 8: 485-487 (2015) (published online on 03 October 2015)

Ploughshare Tortoise (Astrochelys yniphora) natural entrapment

Andrea Currylow1,*, Andrew D. Walde2, Fidelis Filazaha3, Angelo Mandimbihasina4 and Lance Woolaver4

The Ploughshare Tortoise (Astrochelys yniphora; population (Pedrono et al., 2004). Therefore, it is crucial Vaillant, 1885) is the largest extant endemic tortoise that adult animals remain in good health within the wild on the island of Madagascar. The species is isolated populations. Herein, we describe an adult Ploughshare to a small area of mixed palm-savanna, bamboo-scrub, Tortoise found in peril in the wild. and dry deciduous forest of less than 160 km2 on the As part of ongoing monitoring studies of Malagasy northwest coast (Mandimbihasina and Woolaver, 2014). tortoises (Currylow, 2014; Mandimbihasina and Due to its rarity and attractive golden carapace, it has Currylow, 2014; Walker et al., 2014), we have been become an obsession among rare-wildlife collectors. conducting radiotelemetry tracking of wild Ploughshare This pressure from the international pet trade and its Tortoises since early 2012. On 9 March 2014 at highly restricted distribution has given the Ploughshare 16h30, we discovered an adult male Ploughshare Tortoise the unfortunate privilege of being the most Tortoise entrapped between two young Combretaceae endangered tortoise on the planet (Juvik et al., 1981; trees, Terminalia boivinii. The animal had apparently Hoogmoed and Vliet, 1985; Curl, 1986; Rhodin et al., attempted to traverse the gap when the width of its 2011; Kiester et al., 2013). shell prevented clearance. Upon attempts to free The greatest risk to the survival of a wild chelonian itself, the animal scraped the earth away from under population is the loss of the adults, which solely its feet, causing it to become suspended in place and contribute to the sustainability of a population (Congdon hopelessly entrapped (Figure 1). We are unaware of et al., 1993; 1994; Doak et al., 1994). Adults are now how long the animal remained in that position before beginning to be more commonly found for sale in illicit we found and freed it. At the time of discovery, the online pet markets and recent population surveys have ground temperature was 32.2 °C, air temperature 31.2 shown a significant decline of the wild adult population °C, ground humidity 88.8%, cloud cover 10%, and (Kiester et al., 2013; Mandimbihasina and Woolaver, canopy cover over the animal was estimated at 80%. 2014). Because the life-history of tortoises include The nearest conspecifics found that day were two adult delayed maturity coupled with an extremely long females radio-tracked within one hour and which were generation time equating to a slow reproductive rate, no more than 200 meters from the entrapped male. All reproductive adults are critical to the recovery of the three animals were in microhabitat classified as dense bamboo and shrub thicket at the time of encounter. A growing urban-wildlife interface means it is not terribly unusual for wild animals to become inadvertently entrapped, especially due to anthropogenic habitat alterations or devices. For example, in 1992 dozens 1 Department of Biological Science, University of Southern of the closely related Radiated Tortoise (Astrochelys California, Los Angeles, California, USA radiata) succumbed to overexposure in southern 2 Turtle Survival Alliance, Ft. Worth, Texas, USA Madagascar when they fell into an inadvertently created 3 Comité Local du Parc, Baly Bay National Park, Soalala, pitfall trap as part of new road construction (Goodman Boeny Region, Madagascar 4 Durrell Wildlife Conservation Trust,���������� Lot ���IIY����49 J et al., 1994). Cattle grates along livestock fences Ampasanimalo, BP 8511 Antananarivo 101, Madagascar also act as pitfall traps, trapping and killing Angulate * Corresponding author e-mail: a.currylow����������@�gmail.com��������� Tortoises (Chersina angulata) and Padloper Tortoises 486 Andrea Currylow et al.

Figure 1. An adult male Ploughshare Tortoise (Astrochelys yniphora: AY0021M) found suspended between two small trees within its native range in northwest Madagascar. (Photographed by FF).

(Homopus sp.) in South Africa (J. Juvik pers. comm.). fieldwork has been awarded by the Turtle Conservation Fund, More exceptional however, are the instances such as Conservation International, Turtle Conservancy, U.S. Fish that reported herein where herpetofauna may perish & Wildlife Service, University of Southern California, and personally by the authors. Equipment donations were provided by through becoming naturally entrapped. Rorabaugh IDEA WILD, the Turtle Survival Alliance, and Holohil Systems (2003) described a Common Chuckwalla (Sauromalus Ltd. We would like to thank the personal support of our efforts by ater) which became skewered by an agave plant after Drs. A. Ross Kiester, James Juvik, and Craig Stanford. an apparent fall or leap from a nearby rock outcrop. Wilson and Topham (2009) report discovering two separate Mojave Desert Tortoise (Gopherus agassizii) References carcasses wedged vertically (head-down) in basalt flow Congdon, J.D., Dunham, A.E., Sels, R.C.V. (1993): Delayed sexual rock fractures, apparently having died from exposure maturity and demographics of Blanding’s Turtles (Emydoidea after falling and becoming stuck in the rock crack. This blandingii): implications for conservation and management of latter observation is similar in nature to one made by long-lived organisms. Conservation Biology 7: 826−833. Riedle et al. (2010), whereby two of 29 radio-tracked Congdon, J.D., Dunham, A.E., Sels, R.C.V. (1994): Demographics of common snapping turtles (Chelydra serpentina): Implications Desert Tortoises tumbled down a steep rocky hillside for conservation and management of long-lived organisms. in the Sonoran Desert, leading to their eventual death American Zoologist 34: 397−408. from apparent overexposure as they were unable to right Curl, D.A. (1986): The rarest tortoise on earth. Oryx 20: 35−39. themselves in the rocky terrain. Currylow, A. (2014): No refuge at the end of the earth: beating Like many tortoise species, the Ploughshare Tortoise hustlers, poverty, and disease to save the Ploughshares. In: The has adapted to undergo months-long periods of Tortoise magazine, vol. 1 p. 28−37. New York, New York, inactivity during the dry season. However, because USA, the Turtle Conservancy. these animals live in extreme environments, entrapment Doak, D., Kareiva, P., Klepetka, B. (1994): Modeling population viability for the Desert Tortoise in the western Mojave Desert. in the wrong place has the potential to turn fatal within Ecological Applications 4: 446−460. hours. Fortunately, the animal we discovered appeared Goodman, S.M., Pidgeon, M., O'Connor, S. (1994): Mass mortality to be in good health and was in an area of relatively of Madagascar Radiated Tortoise caused by road construction. high canopy cover, so was likely not at immediate risk Oryx 28: 115−118. of overexposure to direct sunlight. Hoogmoed, M.S., Vliet, K.A. (1985): Two reptiles among the 12 most threatened animals of the world. Amphibia-Reptilia 6: Acknowledgements. We thank Dr. Edward Louis, Jr. with 101−115. Madagascar Biodiversity Partnership and Madagascar National Juvik, J., Andrianarivo, A., Blanc, C. (1981): The ecology and Parks for local support of our fieldwork. Funding for associated status of Geochelone yniphora: a Critically Endangered tortoise Ploughshare Tortoise natural entrapment 487

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Accepted by Gonçalo Rosa