Monday, 22 July 2013

Fledgling Success

Friday 12th July saw a major 'terning' point in this years project (no excuses for the terribly awesome pun).

Having had the previous day off, re-acquainting myself with the delights of the 'real world' (namely laundry duties, an overcrowded Dublin City, public transport full of screaming children etc.) I was more than eager to head back to the colony on Friday afternoon & start my weekend shift.

Once back on site, myself & Andrew were stood staring at the colony, discussing the comings & goings of the previous day during our cross-over between shifts, when all of a sudden, a strangely familiar high pitched, squeaky 'peep' call could be heard around the area of The Breaches estuary outlet. Just as expected it was being emitted from a fledgling Little Tern, flying strongly over the beach!

We spent the next few minutes savouring the moment. After watching & protecting these terns every waking minute of the day & night for the past two & a half months it was hard not to get excited by the sight of a fully fledged juvenile having the time of its life flying about the place!

And what's more... it wasn't alone! By the end of the evening we had seen three different juveniles which were fully capable of flight. Fantastic! We reckoned they were from nests K2 (2 young) & K5 (1 young) which would mean they were between 19 & 22 days old between the youngest & oldest of the lot of them.

One of our first fledgling terns © Niall Keogh
These past few weeks of unbroken sunshine & calm conditions have provided optimum feeding conditions for the terns, with chicks being fed from 5am straight through to 10pm with only a short lull during the hottest parts of the afternoon. Sprat seems to be the order of the day for the 10+ day old group of chicks, which are being delivered at a rate of 2-4 per hour per hungry mouth! 

This excellent feeding has led to the chicks developing ahead of schedule & most seemingly taking flight at the younger end of the expected fledging time scale (between 19 & 23 days). As such, dawn & dusk counts along the foreshore are providing us with up to 100% of our expected fledglings each day. Now in the order of c.40 juvenile Little Terns!!! Furthermore, the oldest group of fledglings are now really getting the hang of proper flight & can often be seen up to 100m offshore in loose flocks, practice diving for fish, picking up bits of floating debris & joining in with the occasional 'dread' of flocking adults.

Little Tern fledgling on the younger end of the scale, still with bits of downy chick fluff on its head © Niall Keogh
18 day old Little Tern...ready to take it's first proper flight in a day or two © Niall Keogh

The Breaches estuary outlet into the sea which splits the beach in two near the tern colony had taken a somewhat undesired route for most of the summer, edging slowly Northwards, creating a steep bank which was getting perilously close to the main fence as it eroded away after each high tide (we had to move the corner of the fence inwards on a number of occasions to stop it ending up in the sea!). But thankfully the outlet has been re-profiled by digger since then, changing the course to flowing straight out from underneath the railway bridge. This has left a long shingle spit leading south from the colony where the old outlet used to be and at high tide it is surrounded by water on three sides, creating a perfect 'hang out' for fledglings & waders such as Dunlin. As this area is proving so important for the older tern chicks, we have cordoned it off with rope & signs to ensure none get trampled there. Still a great spot to have a look at from the safety of the opposite bank with a telescope.


Newly formed shingle spit at high tide

A few late nesting attempts (it's getting on a bit now lads!) have also been discovered bringing us up to a total of 45 pairs breeding on the beach this season. Three of the these nests have 'failed' in such that the eggs didn't hatch, even up to a week beyond the latest date for expected hatching. A few nests every year go this way unfortunately but it may simply be a case of the breeding birds in question being quite old, producing infertile eggs.

So as of this evening we have 42 active pairs with 65 chicks (c.40 of which have fledged) & 10 eggs left to hatch over the coming week!

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