Manx Shearwaters breed successfully on a United Kingdom island freed of its rats

Following the successful eradication of Norway or Brown Rats Rattus norvegicus from the inhabited islands of St. Agnes and Gugh in the United Kingdom’s Isles of Scilly (click here) the news is in that Manx Shearwaters Puffinus puffinus are about to fledge chicks on the two connected islands for the first time in living memory.  Although Manx shearwaters have bred on these two islands for decades, eggs and chicks were always eaten by rats while they were still in their burrows.

The latest issue (September 2014) of the Isles of Scilly Seabird Recovery Project’s Rat on a Rat Update has the news:

“Yippee!  We are delighted to announce that Manx shearwater chicks have been spotted peeking out from their burrows and ‘wing-flapping’ on St Agnes and Gugh.  They are the first shearwater chicks to be recorded [outside their burrows] on either island in living memory.  Taking great care, Seabird Ecologist Dr Vickie Heaney, project volunteers and ourselves duly visited the burrows under cover of starlight on four separate evenings from August 29th to September 12th.  The result –10 healthy chicks.  Trail cameras have been set out to collect footage of the chicks’ nocturnal behaviour.”

Manx Shearwaters emerge from their burrows at night on the Isles of Scilly

Click here to view a video clip of one of the Manxie chicks emerging from its burrow at night.

Biosecurity activities on the islands until official confirmation of the rat eradication comes in early 2016 include discouraging and removing food sources by beach cleans, bin days and an ‘Apple Day’ when wind-fallen apples will be collected and juiced. Despite several false alarms no confirmed rat sightings (or of their droppings) have been made since the eradication exercise was completed.

The rat eradication project was undertaken from November 2013 to March 2014 using ground baiting by Elizabeth (Biz) Bell and colleagues of New Zealand’s Wildlife Management International Ltd (WMIL) (click here).

The Isles of Scilly project was recently visited by members of a team that aims to remove Black or Ship Rats R. rattus from Italy’s Tavolara Island off Sardinia to protect its large population of Yelkouan Shearwaters P. yelkouan (click here).  This Vulnerable species was identified as a potential candidate for ACAP listing last year at a meeting of ACAP's Advisory Committee (click here).

With thanks to Jaclyn Pearson, Isles of Scilly Seabird Recovery Project Manager for information and photographs.

John Cooper, ACAP Information Officer, 26 September 2014