Conservation success confirmed on Cosmoledo |25 November 2013

A joint visit to Cosmoledo by representatives of the Islands Development Company (IDC), Seychelles Islands Foundation (SIF) and Island Conservation Society (ICS) has confirmed that for the first time in half a century, Masked Boobies (‘FouZenero’) are breeding at Grand Ile, the second largest island of the atoll. The last known breeding record was in March 1964, when five occupied nests were found plus two young chicks. Rats were eradicated from both Grand Polyte and Grand Ile at Cosmoledo in 2007. The eradication was a major logistical exercise led by Gérard Rocamora for ICS and funded under a Fonds Français pour l'Environnement Mondial project with support from IDC.  Getting a helicopter, all the materials and personnel to Cosmoledo took many months of planning but this latest news is the crowning glory for an ambitious and ultimately successful project.

Since the eradication, opportunities to visit the remote atoll have been few and far between not least due to the modern day scourge of piracy. A pirate attack on a merchant vessel (repelled by security personnel) some 240 miles north of Cosmoledo and just a few days before the joint visit is  sufficient proof that this problem has not yet gone away.

Seven nests were found, some with eggs and one with a well-developed feathered chick. Time and tides only permitted a search over a small area of the island and it is probable the actual population is much higher.  On Grand Polyte too, Masked Boobies were found to be doing well with 50-100 pairs present. No Masked Boobies were found on Grand Polyte during thorough searches in 1996 and 2002, but the species was breeding at the time of the eradication, despite rats. Even so, it is beyond question the rats have a substantial impact on the species. The world’s largest colony of Masked Booby breeds at Clipperton Island in the Pacific Ocean, where 112,000 pairs were counted in 2003 yet in 1958, before rats were eradicated there were just 150 pairs.

Masked Booby is also doing well on other islands of the atoll. On North Island, 500-1,000 pairs were present, considerably more than the previous highest estimate of 250 pairs. Brown Booby (‘Fou Kapisen’) are also breeding on the island and though only seven nests were found, this is also the highest ever figure recorded from this island. Brown Booby is one of the rarest breeding birds of Seychelles, breeding only at Cosmoledo, but unfortunately time and tides did not permit a visit to the main colony of South Island on this occasion.

Not that all the news from Cosmoledo is good news. Sea cucumbers were once very common in the waters of the lagoon but today they are very rare. Sharks too appear to be uncommon. Clearly poaching has been happening despite the deterrent of pirates in the area. The absence of a human presence means that we can only speculate on the scale of poaching and the origin of the poachers.
Hopefully the time is not too far distant when Cosmoledo, the most important unprotected site in Seychelles, receives the attention it deserves including the presence of full time conservation staff. The triumph of the rat eradication shows that big ideas can receive big rewards. Hopefully this is one idea whose time has come.


Adrian Skerrett
Island Conservation Society