Santiago Island giant tortoise

The Santiago Island giant tortoise (Chelonoidis niger darwini), also known commonly as the Santiago giant tortoise^[3] and the James Island tortoise, is a subspecies of Galápagos tortoise in the family Testudinidae. The subspecies is endemic to Santiago Island (also known as James Island and San Salvador) in the Galápagos.

Santiago Island giant tortoise Temporal range: Pleistocene - Recent[1][2]
Conservation status
Critically Endangered  (IUCN 3.1)[3]
CITES Appendix I (CITES)[4]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Testudines
Suborder:	Cryptodira
Superfamily:	Testudinoidea
Family:	Testudinidae
Genus:	Chelonoidis
Species:	C. niger
Subspecies:	C. n. darwini
Trinomial name
Chelonoidis niger darwini (Van Denburgh, 1907)[5]
Synonyms[6]
Testudo darwini Van Denburgh, 1907 Testudo elephantopus darwini — Mertens & Wermuth, 1955 Geochelone elephantopus darwini — Pritchard, 1967 Geochelone nigra darwini — Iverson, 1992 Chelonoidis nigra darwini — David, 1994 Geochelone darwini — Cisneros-Heredia, 2006 Chelonoidis darwini — Rhodin et al., 2010

Population history

Large numbers of C. n. darwini were removed from Santiago Island in the early 19th century by whaling vessels, and introduced goats reduced the coastal lowlands to deserts, restricting the remaining tortoises to the interior. The sex ratio is strongly imbalanced in favour of the males, and most nests and young are destroyed by feral pigs. Some nests are now protected by lava corrals, and since 1970, eggs have been transported to the Charles Darwin Research Station for hatching and rearing. Release programs and measures for nest protection from feral pigs have been successful.^[7] There are approximately 1,165 individuals in the wild, with an increasing population.^[3]

Habitat

The C. n. darwini are diurnal and terrestrial. Their habitats include deciduous forests, evergreen montane forests, and humid grass land.^[8] At maturity they reside in the highlands of Santiago Island in the Galapagos.^[8] However, in the first 10-15 years of their lives the remain in they lowlands of the island.^[8]

Description

The gray to black carapace of C. n. darwini is intermediate in shape between the saddle-backed subspecies and the domed subspecies of Galápagos tortoises. It has only a shallow cervical indentation. The anterior carapacial rim is not appreciably upturned, and the posterior marginals are flared, slightly upturned, and slightly serrated.^{[citation needed]}

Diet

The diet of the C. n. darwini consists of cacti, herbs, and grass found on Santiago Island.^[8] The water in their diet is obtained by the vegetation they consume or by temporary pools.^[8]

Etymology

The specific name, darwini, is in honor of English naturalist Charles Darwin.^[6]