Reintroduction of black howler monkey Alouatta caraya into Cockscomb Basin, Belize


As howler monkeys, Alouatta spp., can live in relatively small areas of forest of a range of ages, reintroduction may be possible once an area has been made safe e.g. from hunting and major forest cutting. Despite this, few reintroductions/translocations have been undertaken, except as fairly last resort rescue measures. A successful translocation of black howlers A.caraya in Belize, carried out from 1992 to 1994 in order to re-establish a viable population, is described here.

Complete troops of black howler monkeys were moved from the Community Baboon Sanctuary to the Cockscomb Basin Wildlife Sanctuary, where they had been eradicated by hunting.

After resolving the problem of hunting, 14 troops consisting of 62 individuals was moved during May of 1992, 1993 and 1994. In most cases these troops were held in pre-release field cages for 2-3 days to assist in acclimatization to their release area, and to observe the animals for any potential difficulties arising from the capture procedure. The translocation was done with extensive prior planning. This included: experience gained from earlier howler captures to establish best capture methods; a feasibility study; doner and release area surveys; evaluation and mapping of the release site; constructing suitable pre-release cages; and telemetry research.

Upon release in the Cockscomb Basin Wildlife Sanctuary, over 90% of the translocated howlers survived for 6 months and many for much longer. The population exhibited a normal (high) birth rate for the species; at least 38 young were born by 1997, and these offspring had an exceptionally high rate of survival. The population was estimated to be more than 100 individuals by early 1997. The extensive prior planning before the translocation was undertaken and careful procedures followed thereafter, are considered to have greatly accounted for the high survival rates and overall success of the reintroduction.

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