Eradicating feral cats to protect Galapagos land iguanas: methods and strategies

Published source details Phillips R.B., Cooke B.D., Campbell K., Carrion V., Marouez C. & Snell H.L. (2005) Eradicating feral cats to protect Galapagos land iguanas: methods and strategies. Pacific Conservation Biology, 11, 257-267.
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This study is summarised as evidence for the following.

	Action	Category
	Release captive-bred reptiles into the wild: Snakes & lizards Action Link
	Remove or control predators using lethal controls: Snakes & lizards Action Link

Release captive-bred reptiles into the wild: Snakes & lizards

A replicated study in 1991–1993 on a tropical island in the Galápagos, Ecuador (Phillips et al. 2005) found that following release of captive-bred Galápagos land iguanas Conolophus subcristatus, some survived and reproduced. Between 17–32 iguanas were recaptured/year. More offspring of released iguanas were captured after most cats Felis catus were eradicated from the island (1 and 14 adults and 6 and 14 sub-adults and juveniles/year) than before the cat control program began (1 and 0 adults and 6 and 4 sub-adults and juveniles/year). In 1991–2003, a total of 183 captive-bred iguanas were released over six releases (15–63 released every 1–5 years). Cat eradication started in 2001 and was completed in 2003. Iguanas were surveyed (6 days in June–July) before (1999–2000) and after (2002–2003) the majority of cat eradication had been completed.

(Summarised by: Maggie Watson, William Morgan)
Remove or control predators using lethal controls: Snakes & lizards

A before-and-after study in 1999–2003 on a tropical island in the Galápagos, Ecuador (Phillips et al. 2005) found that during an ongoing iguana reintroduction, more offspring of Galapagos land iguanas Conolophus subcristatus were captured following a successful cat Felis catus eradication program. Results were not statistically tested. The number of offspring of reintroduced iguanas captured was higher after most cats were eradicated (1–14 adults and 6–14 sub-adults and juveniles/year) than before eradication began (0–1 adults and 4–6 sub-adults and juveniles/year). The number of reintroduced iguanas that were recaptured varied throughout the study (after most cats eradicated: 21–32 individuals/year; before eradication: 17–30 individuals/year). Reintroduction efforts were ongoing through the study, with six releases totalling 183 individuals during 1991–2003. In 2001–2003, cat eradication was carried out with poison baits (1080 poison), trapping and shooting, and cats were considered eradicated by 2003. Iguanas were surveyed (6 days in June–July) before (1999–2000) and after (2002–2003) the majority of cat eradication had been completed.

(Summarised by: Maggie Watson, William Morgan)