Saturday 11 June 2011

Terns - the latest





Using the tern platforms - spot the 2 eggs.



The Beacon colony at sunset


Giving a gull a hard time.

About to dive bomb an intruder.


These terns are super birds and superbirds and so I thought that it might be good to keep you updated on what they are doing on the island at the moment. Well it has been a bit of a roller coaster ride with them so far. After returning in lower numbers than usual but getting settled in the usual places they then disappeared for a couple days. They then came back but the big storm on 23 May stirred them up and the smaller groups at Kirkhaven and the Priory disappeared again while the Beacon birds looked like they might go as well. We were so sure that they had left the colonies at the Priory and Kirkhaven that we took down all the ropes and signs that keep the visitors from getting into their nesting areas but no sooner than we had done that than they were back and in force. So the current state of play is that we look to have some 25 pairs at Kirkhaven, 25 pairs in the Priory and maybe 2-300 pairs up at the Beacon. But what is especially welcome is that they seem determined to breed this year after 2 years of rather half-hearted attempts.
Now terns can be a bit fickle, they can just up sticks and go at any time during the season or just not come back the following year. It seems that it is in their character and is maybe an evolved characteristic that helps them take advantage of the changeable nesting habitat of bare ground that they use. Their eggs and chicks are also very vulnerable to gull predation so at the moment Rinchen is doing daily watches over the colony to try to work out how much effect the gulls are having. A couple of hours spent in the tern hide is a very entertaining experience. Terns could start an argument with themselves in an empty room. There is always a huge amount of chattering, screaming and stress going on in a tern colony and even at dusk they are still muttering to themselves seeming to relive the conflicts of the day. Anything that strays in to air space or ground territory is given a going over, often by the whole colony and this can include eiders, gulls, young rabbits, oystercatchers and humans. It is a very satisfying to see a large gull yelp as it has its tailed feathers tweeked by a swarm of angry terns. And perhaps the most satisfying thing of all is that some of the terns have laid eggs on the tern nesting platforms that the BTCV volunteers built earlier in the season. These offer a small patch of ideal nesting ground but with cover for chicks nearby. So if any of the BTCV vols are reading this, then well done chaps, the terns like them.

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