27 July 2012

Seek and ye shall find

I've been monitoring my local Kittiwake colony over the summer as part of a RAS (Retrapping Adults for Survival) project. The site is Rinsey Cliffs in west Cornwall and is one of the largest colonies in the county, holding up to 120 pairs in recent years. But the poor weather this year has dropped the number to 84, of which only around 65 have actually nested. But what I have seen are several French-ringed birds, easily identified by their unique combinations of colour rings. Over the summer I've recorded five different French birds in the colony, though don't yet have ringing details on these (although they'll be from colonies on the Brittany peninsula).

Some of these birds are what are known as 'squatters': young birds which visit other colonies looking for breeding sites. These birds, sometimes up to six or seven years old, will squat an active nest over the summer, taking over that nest in future years when it becomes available.

But not all have just been squatting and at least two have bred this year, showing how much interchange there must be within these local colonies. As part of our own colour-ringing of adults, we also caught a bird that had originally been ringed as a chick on the Isles of Scilly in 1999.

But as the summer progressed I 'lost' a few of my birds from the colony and did fear the worst. But a chance encounter whilst out climbing solved the problem and an afternoon of climbing/scrambling located a small satellite colony of around 20 pairs a kilometre from my main site. Incredibly, this site yielded two more French colour-ringed birds!

This is all the more incredible as there are previous reports of just six French-ringed Kittiwakes in Cornwall and only 70 in the whole of the UK! So seven in one area in one summer is exceptional, and certainly shows that if you do make the effort to look for these things then the rewards can be great.

Colour-ringed birds can be reported online via www.ring.ac or direct to the scheme coordinator via the cr-birding website.

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