Mew Island Terns

The Mew Island Tern Project

(Update to the end of May 2003)

Early in 2002 we were contacted by Norman Ratcliff, the RSPB’s specialist in Roseate Terns, who is trying to reverse the long-term decline in numbers of Roseates breeding in the UK. Norman wanted to discuss the potential for attracting Roseates to breed again on Mew Island. Over the next few months we began to work up a plan for Mew. In July, Pat and Neville McKee and John Stewart visited Coquet Island off the Northumbrian coast, where the RSPB manage part of the area for breeding Roseates. This was followed by a visit by Norman and Dave Allen to Mew when we agreed a strategy to make the Island more attractive to terns.

Some factors are already favourable. Arctic Terns already breed in some hundreds on nearby Big Copeland and, at the RSPB’s Belfast Harbour Estate Reserve, Anthony McGeehan has been successful in attracting Common Terns to nest on a shell-covered, artificial island. This suggests there is a good food supply locally available. A point readily confirmed by those of us who use the Chris Bailey hide to seawatch out over Mew Island. The Arctic Terns from Big Copeland are constantly shuttling back and forth past Mew, carrying fish back to their nest. The population of large predatory gulls is much reduced on Mew and Lighthouse Island and there are no breeding birds of prey (although there are regular visits by Buzzards, Peregrines and Sparrowhawks). There are no ground predators such as rats or other mammals on Mew.

On the down side, the vegetation on Mew is very rank and unlikely to be acceptable to terns.

Although our target species is the endangered Roseate Tern, it is known that Roseates will rarely adopt a new site unless there are already other terns, particularly Common Terns, breeding there. The explanation is thought to be that Roseates are not sufficiently agressive to drive off predators on their own, and prefer the safety of nesting near their tougher cousins. Our initial target therefore is to attract Common Terns to breed on Mew.

What do we need to do to attract Common and other terns? We have a safe site with food nearby, the missing element in the equation is appropriate nesting habitat.

Our first task, therefore, was to find a way to get some of the vegetation under control. Suggestions ranged from burning, to weedkilling, to grazing, to strimming and to killing by excluding light using carpet or plastic sheeting. Eventually, however, we settled on the idea of hand-pulling the tussocks in small patches, covering the bare ground with horticultural membrane and then laying down a few inches of cockle shells on top. Once this was in place, we would position decoy terns, deploy tern nestboxes and play tape recordings of terns – all with the hope of attracting some terns to visit the site and hopefully to return to breed there.

We had decided what to do, the next step was to find a way of doing it! As ever, we needed finance and volunteers. Both were soon forthcoming. We applied for, and have received, a grant from the Environment and Heritage Service of the Department of the Environment. The RSPB offered some help with funding and with carrying out the work. BirdWatch Ireland have kindly loaned us some decoys and a sound system to play the tape recorded calls of terns. And, of course, our own members quickly volunteered their time for all the preparation work.

At Easter 2003, a couple of tonnes of cockle shells, collected over the winter by Boyd Bryce, were transported to Mew. This was followed by a day trip to prepare four separate areas for the terns. After some running repairs to the sound system, which hadn’t been used for a couple of years, that and the decoys and nestboxes were in place at the end of May. Now we wait!