RED-TAILED TROPICBIRD

At first glance, the Red-Tailed Tropicbird (Phaethon rubricauda) is doing well in comparison to Abbott's Booby and Christmas Island Frigatebird. The species is relatively common in tropical oceans and globally not endangered, and Christmas Island harbours the largest Australian breeding colony of this species (about 1,400 breeding pairs). In 2006, however, we discovered within the framework of the Seabird Project that this bird is acutely endangered on Christmas Island as chick mortality amounts to over 90 %, a rate at which the population on the island will slowly but surely become extinct.

First investigations have shown that many chicks are preyed upon by introduced cats. As part of the Seabird Project, it is investigated how many chicks die due to cat predation and why cats can kill the chicks in the first place as chick-rearing adult tropicbirds are very protective and fight off predators. Among others, the investigations encompass regular nest monitoring, behavioural observations and nest surveillance with video cameras. In addition, prey spectrum, fitness and immune competence are determined of adults and chicks. With this information, it will be possible to develop and to successfully implement protection measures for the Red-tailed Tropicbird.

And the first success is achieved: both the National Park and the Shire of Christmas Island have started to tackle the cat problem! This is a first step in the right direction!
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