Biological Invasions

, Volume 1, Issue 4, pp 363–375 | Cite as

Restoration of Insular Ecosystems: Control of Feral Goats on Aldabra Atoll, Republic of Seychelles

  • Raymond E. Rainbolt
  • Bruce E. Coblentz


The control of feral goats (Capra hircus) was studied on Aldabra Atoll, Republic of Seychelles, from October 1993 to May 1994 and November 1994 to May 1995. A total of 832 goats was killed on Aldabra using the Judas goat technique and traditional hunting methods. Twenty-eight goats equipped with radio transmitters (Judas goats) were used to locate and kill other feral goats. The remnant goat populations on Ile Picard (n=13) and Ile Malabar (n=19) were eradicated during the first season. On Grande Terre, a total of 798 (374 M : 424 F) goats were killed. Mean group size was 3.2 with a range of 1–20. Judas goat hunting became increasingly important over time with 18.0% (n=85) of goats killed in the presence of Judas goats in the first season compared to 42.3% (n=126) of goats killed during the second season. The overall kill rate for the project was almost 2 times greater for Judas goat hunting (0.61 goats killed/h) than traditional hunting (0.32 goats killed/h). The home range size of each Judas goat and the number of goats killed in association with it was significantly related. Using the Leslie–Davis removal method of population estimation, 84 goats were estimated to remain on all of Grande Terre at the end of thebreak project.

Aldabra Atoll Capra hircus control eradication feral goat Judas goat technique 


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Copyright information

© Kluwer Academic Publishers 1999

Authors and Affiliations

  1. 1.Department of Fisheries and WildlifeOregon State UniversityCorvallisUSA

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