Santiago Galápagos Mouse
The Santiago Galapagos Mouse, Nesoryzomys swarthi, is listed as ‘Vulnerable’ on the IUCN Red List of Threatened Species™. Believed extinct until its rediscovery in 1997, this species occurs only in a small area of the island of Santiago, in the Galapagos.
The endemic ‘rice rats’ have lost more species than any other group of vertebrates in the Galapagos, largely due to the introduction of Black Rats, mice and feral cats to the islands. Although it currently coexists with the Black Rat, the Santiago Galapagos Mouse is thought to owe its survival to areas of Opuntia cacti, which act as refuges from competition, and to its greater ability to withstand drought. Unfortunately, habitat change may allow Black Rat populations to explode, while at the same time decimating vital Opuntia habitat.
The most vital conservation measure for the Santiago Galapagos Mouse will be the eradication or control of introduced species. Projects are also underway to monitor and study the species, and an action plan has been proposed, together with the possibility of establishing a captive population.