Focus on warblers…

The Seychelles warbler (Acrocephalus sechellensis) is an iconic species for Seychelles conservation. In the 1960s the entire global population of only 20-25 birds was restricted to a small area of mangroves on the tiny island of Cousin. This led to the purchase of Cousin by the Royal Society for Nature Conservation in 1968 and the subsequent management by the then International Council for Bird Preservation (now BirdLife International).
The purchase of Cousin in order to save the warbler is often considered the dawn of modern conservation in Seychelles. In the following years natural vegetation was allowed to regenerate on Cousin and the Seychelles warbler population expanded and spread throughout the island. In 1988 warblers were introduced from Cousin Island to Aride and then to the neighbouring island of Cousine in 1990. Both introductions proved to be successful in particular the introduction to Aride where birds were reported to be nest-building within a day of their release on the island! The population of warblers on Aride today numbers more than 2,000 birds and the world population now likely over 3,000 – a most remarkable success!
58 Warblers were introduced to Denis Island in 2004 and follow up surveys of the island population 2005, 2006 and 2007 have shown a steady expansion of the warbler population on the island. The introduction of the warbler to Denis contributed to the downgrading of the threatened status of the species to Vulnerable under World Conservation Union (IUCN) criteria.
Logistical problems meant the island was unable to host researchers in 2008 to follow up on the monitoring of the population but I am happy to report that a survey of the population will be undertaken in 2009 so keep a look out in the coming months for updates on the status of the Seychelles warbler on Denis Island.