Friday, 2 August 2013

And they're off!...

The past week has brought about a change in the mood of the terns as well as a decrease in the numbers present at the colony, signalling the beginning of the end of the breeding season.

We've noticed that the terns seem to be a lot more agitated, with frequent flocking flights ('dreads') out over the foreshore, some of which end up far out to sea, flashing like a shoal of fish as they twist & turn
in a tight-nit ball.

On their return to shore, it would often appear that the flock is somewhat smaller than before. I reckon a few birds use these 'dreads' as an opportunity to peel away & start making their first move South of the Autumn. I guess this 'agitated' behaviour shown by the terns may well be an eagerness to get moving with the frequent 'dreads' kicking off the process.

Adult Little Tern in flight © Ronnie Martin

Another more obvious factor at play lending to the nervous disposition of the terns is the presence of a juvenile Peregrine racing through the colony each morning! The young falcon is most likely still being fed by its parents (an adult female has been seen about too) and it never really seems to make an honest effort at catching the terns despite getting quite close on a number of occasions. Most likely what is happening is that the bird is simply honing its hunting technique which will be vital if it is to survive its first winter. It has also been seen chasing after Manx Shearwaters out at sea! Thrilling to watch this soon to be apex predator in action & heartening to know they've bred successfully in Wicklow after recent news of persecution of Peregrines has just come to light.

So with the hint of Autumn in the air & the added push of a predator in the vicinity, daily counts of the terns have dropped from 150+ adults & 50+ juveniles last week to 70+ adults & 20+ juveniles at the moment. We've also received reports of adult & juvenile Little Terns seen recently at Dalkey, Co. Dublin & Tacumshin Lake, Co. Wexford, sites where the terns do not breed but can visit during migration.

Juvenile Little Tern © Niall Keogh
Furthermore, during a count at the Kilcoole colony on Tuesday evening, I noticed a very advanced looking juvenile present which was unringed! Not one of 'our' birds therefore, perhaps one which has travelled south from the colony at Baltray? We have also been seeing the other species of terns making their way past Kilcoole in recent days, with adult & juvenile family groups of Sandwich, Roseate, Arctic & Common Terns heading North for the staging area at Dublin Bay where they will feed & rest for the next month before making the big push South for the Winter.

So all in all, the terns are on the move and whilst the beach is starting to quieten down, this is ultimately what we want to see at this stage of the season. Good to know that the fledglings are strong enough to be making this first leg of migration & the rest of their lives!

We're now watching over the final 15 chicks left which have still yet to fly. We expect them to do so by the middle of the month & we will remain on duty until then to ensure they make it!

Juvenile Little Terns in flight © Peter Cutler
The young terns can be seen practice fishing along the foreshore of the colony at the moment. Yet to see them catch anything though!

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