Seychelles warbler © Jeff Watson
In June of last year, along with our partners we organised for 58 adult birds to be translocated by helicopter from Cousin to Denis. The birds were released in the middle of the island, where the vegetation had been enhanced by our previous work in eradicating alien plants and planting native trees. We were as confident as we could be that, thanks to the hard work of all involved, the restored island was ready for the Warblers, and that they would take to their new habitat. But of course nothing is certain in nature.
Happily, close follow up of the released birds has shown that the operation has been a success. In fact we’ve been amazed at how quickly the birds settled. All but two of the birds were seen again in 2004. Pairs formed just five hours after release. These first pairs started nest building within three days of arrival. In total, 20 territories were located, of which 15 had breeding attempts.
In January 2005, researchers made a five-day visit to check on the population. Many young birds were observed, some of which were already nesting. Breeding seemed to be continuous. The evidence was extremely encouraging, and a complete survey has been undertaken, from June to September 2005, to establish exactly how well the population is faring one year on. The study also looks at how the Cousin population has been ‘filling any gaps’ left when the 58 birds were removed.
The survey work has only just been completed, but the early signs are that the Denis population is continuing to flourish, and the Cousin population from which it originated has quickly recovered to its original level. This is more great news for conservation in Seychelles, and adds to our knowledge of how habitat restoration to re-establish populations of endangered species can work.
In addition to this project, the research team has also been looking at other fascinating aspects of the Warbler’s ecology. Previous studies have shown that the species has a cooperative breeding system. Young birds from one brood will often help with the rearing of subsequent broods, by a combination of joint nesting - more than one female laying eggs in the same nest - and helping to feed the young at the nest. The researchers are also looking at the effects of parasites on the health and vitality of the warblers, and at how the birds disperse to occupy new territories.
With so many expert eyes looking at so many different aspects of its lifestyle, the future of the Warbler is looking better than it has for many years: another feather in the cap for Seychelles conservation.
Nature Seychelles, published on Regar Newspaper, Seychelles, 8th October 2005