Impact of a trade moratorium on populations of yellow-crested cockatoos Cacatua sulphurea at four forest sites on Sumba, Nusa Tenggara, Indonesia

  • Published source details Cahill A.J., Walker J.S. & Marsden S.J. (2006) Recovery within a population of the Critically Endangered citron-crested cockatoo Cacatua sulphurea citrinocristata in Indonesia after 10 years of international trade control. Oryx, 40, 161-167


This study is summarised as evidence for the following.

Action Category

Use legislative regulation to protect wild populations

Action Link
Bird Conservation
  1. Use legislative regulation to protect wild populations

    A before-and-after study on Sumba, Indonesia (Cahill et al. 2006), found that estimated population densities of citron-crested cockatoos Cacatua sulphurea citrinocristata increased between 1992 and 2002, following the imposition of a ban on trade in wild-caught birds in 1993. Increases were seen over the entire study and at two out of four forest sites (by 130-700%). One further site showed no change in density and the final site a possible decrease. No evidence was found for forest contraction (i.e. increased densities are thought to reflect an increase in total population sizes), total recorded birds increased by 56% from 1992-2002; significantly more birds were in groups of two or more and the estimated population size was 90% larger in 2002. The authors note that the trade ban has not been enforced perfectly, but that it has significantly reduced the number of wild-caught birds being traded.


Output references

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