Friday, 26 July 2013

The Omega Egg

Most years we find that the breeding progress of the colony is staggered & generally forms two distinct groups, one lot which breed in the traditional first week from mid-late May & another which begin sometime in the first week of June. This was true again this year but we also had a run of late nests into the first week of July, most likely re-lays from the small number of losses incurred at the egg stage (due to abandonment, Oystercatcher predation etc.).

The 6 pairs or so of terns which nested latest finally made it around to hatching over the past couple of days. Amazing to think that these day old chicks had no problem weathering the heavy rain, thunder & lighting on Wednesday night!

As such we are down to our last nest with one egg waiting to hatch. On checking it this morning, the egg showed some early signs of life poking out from within (faint lines starting to appear on the shell) so with a bit of luck we'll have our last chick out & about by early next week at the latest. With that we should expect our latest chicks to fledge sometime around the end of the third week in August.

So as of this afternoon we have 42 active pairs with 47 fledglings, 27 chicks & 1 egg left to hatch.

Nest K50...Paddy Last! © Niall Keogh

Thursday, 25 July 2013

Terns Feel The Heat

Trust the Irish to spend all year wishing for sunshine & warmth but when it does finally come it suddenly gets "too hot"!

At least for the terns they have a genuine excuse. The heat generated off a shingle beach on a sunny day is quite a few degrees higher at ground level than what we experience several feet up. This is partially the reason why terns, as well as plovers & Oystercatchers, choose to nest on shingle & sandy beaches. Not only are their eggs & chicks well camouflaged against it, but those extra few degrees can make all the difference when it comes to keeping them alive.

But saying that!... Over the past two weeks it was often quite apparent that even the terns & plovers were starting to reach their limits. A scan along the beach on a hazy afternoon often revealed chicks & adults lounging around on the shingle with their eyes squint & beaks open, trying to keep cool (thermo-regulating). Some chicks could also be found trying to make the most of whatever shade was available, huddled against lumps of seaweed or driftwood washed up on the shoreline.

A warm chick poking it's head out from underneath it's equally warm parent! © Andrew Power
A rather uncomfortable looking fledgling © Niall Keogh
Prior to the chicks hatching, we provided the terns with a simple, yet effective source of relief from the elements. A total of 30 'chick shelters' were deployed along the beach in areas where we felt would be of most use, often a few meters on the seaward side of each nest. The shelters themselves are concrete roof ridge tiles, about 2 foot long. The grey colour of the shelters blends in perfectly with the shingle & they are sufficiently long enough to stop a chick being dragged out by a Sparrowhawk or Kestrel. In previous years they have been occupied by chicks during spells of heavy rain but this year we are recording good uptake but for completely the opposite reason! Both large fledglings & smaller 'fluffy' chicks can regularly be seen whiling away the hottest parts of the day under the shelters, waiting patiently for the parents to arrive back with a juicy, fluid filled fish.

A small tern chick taking refuge from the baking midday sun © Andrew Power
A nearly fledged tern, cooling down © Niall Keogh
Even some of the young Ringed Plovers have been seen hanging around the shelters © Niall Keogh

In years gone by, hot summers have led to some chicks dying due to over-exposure but thankfully this year we haven't recorded any losses as such. Chick shelters doing their job so! 

Anyways, back to rain...

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!

Tuesday, 2 July 2013


The June Spring Tides which caused so much heartache in 2012 came & went this season without any hassle thanks to prevailing light-moderate Westerly winds. Furthermore, a good spell of dry, warm weather has ensured that the first group of chicks to hatch since Sat 22nd June have been treated to optimal conditions during their crucial first few days of life.

We've been weighing & measuring each new brood regularly as well as observing the species, size & frequency of fish brought in by the adults. Initial results are looking good with one chick in particular jumping from 7.2 grams on the day of hatching to 18.55 grams three days later! The parents of a brood of three have been kept busy & were noted bringing in as many as 12 fish (mostly small sandeels) per hour yesterday evening!

The majority of the chicks are now very mobile & have been led by their parents away from their original nest scrape, out of the main area of fencing & onto the foreshore. This is normal behaviour & a sort of tern 'creche' will form along the mean high water mark over the coming weeks where feeding can be observed throughout the day. Access to the foreshore alongside the colony is still restricted in order to avoid any unwanted trampling so if you're planning on visiting the beach at Kilcoole please follow on site instructions as laid out by the wardens.

Monitoring chick growth & development...a tough job! © Niall Keogh
Adult & chick © Niall Keogh
Rare moment seeing a tern chick just after hatching © Niall Keogh
It seems to be an odd year with regards potential predators. The 'usual suspects' such as Fox, Hedgehog, Hooded Crow & Rook have all been thin on the ground for the most part with very little corvid activity on the beach or in the estuary, just two Hedgehogs found at night along the coastal track (usually a good few more expected by now) & Cole reports just the one sighting of a Fox near the beach well to the North of the colony which legged it as soon as he saw it.

Saying that, we have experienced some losses to less familiar species, namely Oystercatcher & Sparrowhawk. A total of 3 nests with 2 eggs each were eaten by an Oystercatcher between 19th & 25th June. We have been closely observing all the Oycs in the vicinity & it would appear that the individual in question is a lone non-breeder which has been seen foraging in the tideline near the colony. Our resident breeding Oycs have taken no notice of any nesting tern nests near them all season & have proved invaluable as colony 'security', chasing away any potential avian predators that fly over the beach. In fact, they have also been chasing this lone Oyc off their territory & as such it hasn't been seen in quite a few days.

Little Tern eggshell after being poked & eaten by an Oystercatcher © Niall Keogh

A male Sparrowhawk caught an adult tern at 05:30am on 20th June after which a pile of plucked tern feathers was found along the west boundary of the flexi-net fence. The first proven case of predation by Sparrowhawk at the Kilcoole Little Tern colony since 1997! It made a further six attempts on the colony over the next five days but luckily the terns & Oycs had caught on to the Sprawk's ambush tactics and promptly saw him off with great enthusiasm. The same can be said for the wardens who chased after it also!

Remains of an adult Little Tern after being caught & plucked by a male Sparrowhawk © Niall Keogh

But aside from these unusual predation events, we're happy to report everything else is going well. Eggs are hatching on time, chicks are getting stuffed with fish, disturbance has been kept to a minimum & the support from the local public seems to be ever growing (lots of folk enjoying nice views of chicks lately!).

So as of this afternoon the scores on the shores are as follows: 37 active pairs with 36 chicks & 34 eggs left to hatch.

Not sure if anyone has told this chick that it will be another 3 weeks or more before it will fly. Hasn't stopped it from exercising its wings all the same! © Niall Keogh