Thursday 30 June 2011

Roseate Tern Outings & News

The South Dublin Branch of BirdWatch Ireland will be hosting a series of 'Tern Watch' events at Coliemore Harbour, Dalkey, Co. Dublin every Tuesday evening throughout July (5th, 12th, 19th & 26th) between 18:30 & 20:00. Branch members will be present with telescopes, allowing participants to view the terns on Maiden's Rock where 24 pairs of Common & Arctic Terns as well a pair of Roseate Terns bred this year. All are welcome to the event so why not pop down some evening next month for a look?

More info on the Dalkey Tern Project can be found on the following link:

The Roseate Tern colony on Rockabill, located off Skerries in north Co. Dublin, has had another bumper year with 1,109 AON's (Apparently Occupied Nests) recorded during the 2011 breeding season. Common Terns are doing extremely well on 'The Rock' too with 2,149 AON's this summer (another new record) whilst a smaller population of Arctic Tern's is also present (160 AON's). BirdWatch Ireland staff are present on site each summer to warden the terns & monitor their breeding success. They also provide large numbers of tern nest boxes which has played a significant role in the increase in the Roseate Tern population there over the past few years.

Roseate Terns © Billy Clarke
No. of breeding pairs of Roseate, Common & Arctic Terns on Rockabill, Co. Dublin 2006-2011 © BirdWatch Ireland

Monday 27 June 2011

A grand day for flying

On Friday I saw a chunky chick (c.18 days old) make a short, low flight for a few meters along the foreshore which is to be expected from birds of that age, but yesterday there was a good dozen or so proper fledged juvenile Little Terns flying around the colony & one was even seen indulging in some practise fishing! We were absolutely thrilled to bits with this as the oldest chicks are just 23 days old, meaning they've fledged at a similar age as last year but a week earlier by date. I thought it might have taken a few more days for them to do it but no doubt the warm & windy weather over the weekend beckoned them into the air.

One such 'chunky chick' wing stretching © Jamie Durrant
Another chunker © Niall Keogh
A 'proper' Little Tern fledgling! © Niall Keogh
A good scan of the foreshore this morning revealed at least 23 fledglings resting up & preening whilst still being tended to by their parents (it'll take a while before they can start fishing for themselves). The other exciting news this week relates to the continued finding of new nests, with another 10 being located & marked since my last post! There has also been another run of hatching lately, so our total stands at 80 pairs with 104 young (incl. fledglings) & 52 eggs left to hatch!!!

A new arrival © Niall Keogh
Whilst it's great to get this many pairs on site, the large arrival of late breeders is somewhat worrying for two reasons, (1). they have more than likely come from another colony which suffered some form of heavy predation/disturbance/flooding & (2). they're running out of time to get the eggs hatched & chicks fledged successfully! The likelihood is that some of these nests may abandon whilst others will stick it out to the end but won't fledge their young until mid-late August.

With all these breeding birds about there has been great activity at the colony with up to 100 birds in the air at any given stage today. The terns are getting really aggressive too while they're at it, chasing every gull (from Little to Great Black-backed!) that passes along the foreshore whilst faecal spraying of wardens has reached a whole new level!

Our other colonial inhabitants, the Oystercatchers & Ringed Plovers, are also doing very well. The 'Oyc' chicks are coming along nicely & are starting to get some white feathering on the coverts & orange colouration at the base of their beaks. Four broods of Ringed Plover chicks have fledged & there are currently 3 pairs incubating their second clutch of eggs & 1 pair with a second brood of chicks already hatched & on the go! A real contrast to the disastrous year they had last year.

Oyc chick & adult © Niall Keogh
Predator-wise, thankfully it's been pretty quiet. The only recent loss was of an adult tern which was taken by the 'resident' Peregrine over the K-colony on the 22nd, making 3 that she has predated so far this season. The Kestrels have been well behaved this year (for now!) with only one unsuccessful attempt at taking a chick observed. A big female Sparrowhawk has been seen around The Breaches hunting waders & several Foxes are ever present in the fields inland from there but there has been no mischief out of them yet either. Cole caught a Hedgehog trying to nuzzle in under the K-colony fencing last week which was only the second one he has found this season (compared to 9 last year).

Just as the Solstice passed & Autumn began again (yes I'm a pessimist!), so too did the birding begin to pick up. There was some nice passage this morning involving what I assume are failed breeding gulls & terns from the colony at Lady's Island Lake in Co. Wexford heading for the post-breeding roost sites in south Dublin Bay. Small groups of Sandwich Terns & Black-headed Gulls were moving north with a few Common Terns, Arctic Terns, 3 adult Mediterranean Gulls & even 4 cracking adult Roseate Terns thrown in for good measure which flew right through the K-colony calling loudly. Plenty of waders over the past week also with up to 150 Curlew migrating south in a day & a few other nice bits n' bobs like Bar-tailed Godwit, Grey Plover, Common Sandpiper & summer plumaged Redshank. A Dunlin of the race 'arctica' (from Greenland) on 16th June was perhaps the most interesting bird of the lot.

A couple of juvenile Stonechats were seen down near the BirdWatch Ireland reserve at Kilcoole train station, with one eventually making it's way down to the wardens caravan site. Good to see some successful local breeding of this species whose population has crashed due to recent cold winters. The infamous Cuckoo has finally moved on, which is a blessing to both the terns & the wardens (I was getting tired of chasing it off!).

The flock of eclipse plumaged Mallard is starting to build up in Webb's field & there was even 5 Gadwall with them there today. Up to 8 Little Egrets (incl. 3 juveniles) & a Kingfisher have been seen there too. A drake Tufted Duck & a drake Teal in Stringer's channels were also noteworthy for the time of year. The 21st June brought some interesting seawatching with c.5,000 Manx Shearwaters moving north in the morning along with 4 Arctic Skuas, a Little Gull, 7-8 Storm Petrels & 6 Common Scoter later that afternoon. A stunning summer plumaged Red-throated Diver has been present close offshore in recent days & a 'winter' plumaged Great Northern Diver was even seen out there too.

The Otters are again, ever present, whilst a mother & calf Harbour Porpoise offshore & a Stoat at Webb's farmyard were the only other recent Mammalian highlights.

Juvenile Stonechat © John Fox 
Cuckoo © Jamie Durrant
Summer plumaged Red-throated Diver, a real cracker! © Jamie Durrant

Wednesday 22 June 2011

Branch Trip Update

Just a quick post to say that the Carlow & Wicklow Branch outing to the colony on Sunday went really well with c.35 people in attendance which was great. It was really nice meeting you all!

As well as getting a close up look at some Little Tern chicks, we also saw some Lapwing fledglings & migrating Curlew in Webb's field, a nice colony of Pyramidal Orchids in the dunes & some Black-tailed Godwits in The Breaches.

Having a look at some rare breeding birds in Webb's field (NPWS nature reserve) © Andrew Power
We were lucky to get some nice weather for a change! © Andrew Power
Niall showing some c.2 week old terns to the group, explaining the processes of ringing, chick growth & wing development © Andrew Power
The terns have been doing well since the high tide & strong winds on Friday buried the seaward fence & washed out a few nests. There's been no indication of any major loss & we've even had quite a few new nests in the past couple of days so as far as I'm aware we currently have 70 pairs with 75 chicks & 65 eggs left to hatch! I'll bring you guys up to speed with colony news as soon as I have more time to write-up a bigger blog entry, in the meantime we're slowly tipping away at getting the seaward fence back up & running!

Friday 17 June 2011

Saturday outing cancelled!

Hi guys,

A South Easterly storm coupled with a hide tide lashed across the seaward section of the colony today, wrecking the foreshore fence, washing away 3 nests with eggs & taking 2 chicks for sure. More than likely more chicks have been lost but it will take a few days of censusing to determine the extent of the damage. Saying that we still have 28 pairs on nests with 65 eggs & potentially up to 36 pairs with 64 chicks although that remains to be confirmed!

A couple of positive points:
1. Plenty of half-grown (up to 2 week old) chicks seen high up, in the middle of the colony today. Birds of this age are usually found right down at the edge of the foreshore so it was encouraging to see that they had the good sense to run away from danger. They're also beginning to wing-stretch too (first fledglings expected by next weekend!!!).

2. Quite a few smaller chicks (<7 days old) were seen wandering along the foreshore after the storm abated which is a relief!

Anyways, the Wicklow Branch outing to the colony tomorrow is CANCELLED and will be moved to Sunday 19th June where they will join the Carlow Branch on their outing which will go ahead as normal, meeting at Kilcoole train station car park at 10:00am. 

Apologies to anyone who can't make it on Sunday but sure come down any other day when you're free for a visit!

I'll hopefully get an update on the go with all the latest details on Monday/Tuesday.

G'luck!

Niall


The seaward fence, which has seen better days! © Jason McGuirk
This chick was seen sheltering inside a Roseate Tern nest box (which we put out for the craic to see if Little Terns would nest in it - which they didnt!) © Jason McGuirk

Wednesday 15 June 2011

Little Tern Outings This Weekend

There will be a series of organised outings to the Kilcoole Little Tern colony this weekend, hosted by the wardens & BirdWatch Ireland Local Branches.

The Wicklow Branch will be visiting on Saturday 18th June, meeting at Kilcoole train station car park at 10:00am followed by a short walk along the coastal path viewing both the BirdWatch Ireland & NPWS coastal marsh reserves before finally reaching the Little Tern colony at The Breaches. The tern wardens will be present at the colony with telescopes allowing participants to view Little Terns on nests & with any luck some parent birds feeding chicks.

The Carlow Branch will also be visiting on Sunday 19th June, again meeting at Kilcoole train station car park at 10:00am before heading down to the colony via the coastal reserves, so if you can't make the Saturday outing then why not come along on Sunday?!

A great opportunity to get a good look at one of Ireland's rarest breeding birds. These events are open to all members of the public & are always a firm favourite with families & kids. Please note that children must be accompanied by adults.

Hope to see you at the weekend!

Niall

Little Tern chick from one of last years outings © Terry O'Rourke

Sunday 12 June 2011

Chicks Ahoy!

The first egg hatched (from K6 as predicted) on Friday 3rd June, a full 8 days earlier than last year, but that was to be expected given the early laying this year. Since then we've been busy trying to complete nest checks during what little breaks in the weather we had some days (nest checks aren't undertaken when it's cold or drizzley as the chicks can become exposed & chilled). All chicks have been ringed with metal BTO rings which will allow us to keep track of their survival rates & movements across the colony over the coming weeks. We also measure & weigh the chicks during nest checks as part of an ongoing growth study. 

Little Tern chick, only a couple of hours old © Andrew Power & Peter Cutler 
Niall measuring the wing length of a chick © Andrew Power & Peter Cutler
A couple of nests have single eggs in them which look like they won't hatch but this is normal for a few clutches with three eggs but saying that there are still quite a few broods of three chicks out & about keeping the parents busy. The eggs hatch usually within a day of each other so the difference between the A chick (i.e. the first one to hatch) & the B chick is only a matter of a millimetre or two on the wing & a gram or so in weight. Nest K12 hatched it's three eggs but the third, C chick was found dead in the nest scrape a day later. It was wet when I found it so probably hadn't been brooded that morning during showers. It's two siblings were no longer in the nest scrape so the parents must have started moving them on towards the foreshore pretty quickly. The last time I saw all three of the chicks together it was quite noticeable that the A & B chicks were much bigger than the C chick so I reckon that they were getting the Lion's share of the food & the poor wee fella just wasn't strong enough to survive.

The rest of the chicks are healthy & are being fed some good sized sandeels so it appears that the fish stocks here are in good order (still lots of Gannets diving close offshore these days too which is another positive sign). Quite a lot of the tern broods are already on the move with a lot of the bigger chicks (now up to 9 days old) out beyond the fence & lined up along the foreshore, where the parents leave them whilst they go off fishing.

Chicks are fed on small fish & amphipods for the first couple of days before switching mostly to sandeels. Nest cam footage © Andrew Power & Peter Cutler
 K4 female being fed by the male. Nest cam footage © Andrew Power & Peter Cutler
We've been finding lots of new nests recently too, even up to 8 in a day at one stage so it seems that all the nests that were lost to the Rook, Hooded Crows & abandonment have re-laid. Looking at the nest data chart, this would seem to be the case all right as the dates for re-laying & the size of the clutches (usually an egg less than the original clutch) all match up. The nests lost to corvids in the N-colony appear to have moved to the K-colony to re-lay which means they're now afforded better protection from ground predators due to the more extensive fencing there. Quite a few of the latest nests certainly involve recent arrivals as well as re-lays as there are plenty of full clutches with 3 eggs.

So, as it stands we currently have 70 active nests with 56 chicks & 97 eggs which is amazing given the heavy losses a couple of weeks ago. It just goes to show how resilient these birds can be if they're given enough time & space to breed. As an added bonus, we're also 4 nests above last years total of 66 pairs!!! 

The first Ringed Plover young have fledged successfully & can now be seen feeding along the shoreline in The Breaches. We've also had 3 new nests (totalling 4 chicks & 3 eggs) which could well be second broods/clutches? The Oystercatchers in the N-colony (OC1) hatched 2 of their 3 eggs & the chicks are now to be found near the foreshore being fed regularly on polychaete worms brought in from The Breaches by the male. The eggs from the K-colony Oyc nest (OC2) were beginning to hatch yesterday also!

Early on Wednesday morning (8th June) I was sitting in the hide over-looking the K-colony carrying out some incubation checks when all the terns took flight in a dread at 06:55. Some waders which must have been resting on the foreshore with the terns got up too & I noticed an interesting looking bird with 3 Turnstone. Sure enough it was a BUFF-BREASTED SANDPIPER!!! The 'Buff-B' (as they are affectionately referred to by birders) did a lap of the K-colony right in front of the hide & then continued North with the Turnstones before landing on the beach past the Sea Buckthorn bushes. No sign of it afterwards though. I suppose there's a chance that it is the same bird that we saw here on the 11th May making a return journey? Either way, not a bad way to start the day!

The 2 Cuckoos are STILL here, often showing very well in the Sea Buckthorn or along the K-colony fence. The length of their stay & the fact that they show so well has attracted a lot of attention from photographers & apparently they even got a mention on local radio too! A Short-eared Owl was seen hunting around Newcastle Airfield late in the evening of 2nd June (one seen here last year on 1st June!) & two Kingfishers were seen along the western channel of Webb's field earlier that day. Small numbers of Arctic Terns continue to be seen migrating past every now & then with pairs of Mediterranean Gulls heading North on 6th & 7th also.

The first of the Curlew are beginning to migrate back south already and a few Whimbrel have made an appearance here & there. There's still a flock of 10-20 Dunlin about, often seen roosting on the K-colony foreshore where they attract in Turnstones & Sanderling. A single Redshank & 20-30 Black-tailed Godwits can be found in The Breaches, a flock of 8 Lapwing in Webb's field yesterday may be the first of the returning birds for them too whilst two Snipe can still be heard singing & drumming on Stringer's land behind The Breaches.

A Harbour Porpoise travelled north offshore on 2nd June but we've not seen the 3 Bottlenose Dolphins since. Two Otters are still knocking about The Breaches & Webb's field at night time, munching away on crabs & flatfish. Lots of Leisler's Bats & some Pipistrelle sp. around in the evenings & the first lot of Six-spot Burnet moths are also on the wing.

As you may have guessed from some of the pics above, we're using a nest camera this year. Andrew Power & Peter Cutler are making a documentary on the Little Tern project & they've placed a GoPro camera beside several nests to film some chick feeding (under licence from NPWS). They're already getting some great footage & Peter was kind enough to send on a few stills to use here on the blog. The nest cam will also give us the opportunity to monitor the feeding ecology of tern chicks at a young age & with a bit of luck we might be able to read a few ring codes on the adults too! Anyways, here's a few more nest cam stills for you guys...


K6 adult & chicks. Nest cam footage © Andrew Power & Peter Cutler
OC2 incubating. Nest cam footage © Andrew Power & Peter Cutler
Niall, Peter & Andrew setting up the nest cam beside K6 © Siobhan McNamara
This male tern (from K13) is most likely one of 3 birds from the Wexford Harbour colony that were fitted with blue colour rings when they were chicks in either 1995 or 1997. We're doing our best to try & read the code on that metal ring! Nest cam footage © Andrew Power & Peter Cutler 

Thursday 2 June 2011

Rupert the Rook

In my last post I mentioned that a Rook was the likely cause of the loss of one nest (K43) on Monday 23rd May. Well, I'm afraid to say my suspicions were correct & unfortunately the Rook was back in again on Wednesday...and Thursday...AND Friday!!! It appears that Rupert (the Rook) is a rogue non-breeder who sussed out that mid-week periods of poor weather result in very few people out & about walking along the dunes leaving plenty of opportunity for it to pop in for a few nests then pop out again before anyone would notice! It also had a nasty habit of doing this while the on duty warden was at the opposite end of the colony so a rather cruel game of cat & mouse (or warden & Rook) ensued for a few days. On one occasion the Rook attacked the north end of the K-colony whilst I was monitoring nests at the southern end. In the short space of time it took me to run the 200m to where the Rook had landed in it had already munched 3 nests! That was the kind of determination we were up against! The majority of nests lost were taken on Wednesday/Thursday with the number of attacks decreasing pretty quickly once the weather started getting better around the weekend & more people were out & about walking along the beach/path. Continuous human presence it seems was the best deterrent. All in all a total of 16 nests with 35 eggs were predated by the Rook, which was a serious blow to the colony. Thankfully there has been no sign of Rupert for the past few days now so lets hope he's in a bad way somewhere suffering from the ill effects of high cholesterol due to all those eggs he ate!

K40 - safe & unpredated! © Niall Keogh
Little Tern bringing in a sandeel for it's mate © Niall Keogh
Another two nests (K32 & K55) have abandoned, for reasons unknown. I've heard a theory that prolonged spells of bad weather often result in abandonment so perhaps the high winds had something to do with it? The Peregrine made another pass over the K-colony early on Monday morning taking an adult Little Tern (that's 2 now so far) which to be honest wasn't unexpected. What was unexpected though was the predation of an adult Little Tern by an adult Great Black-backed Gull on Sunday afternoon! The gull was migrating north along the coast when it passed through a flock of terns. It must have seen an opportunity for an easy meal as it whacked an adult Little Tern which then fell to the water & was promptly pounced upon and SWALLOWED WHOLE by the gull! This is the first time that predation by a Great Black-backed Gull has been confirmed at the colony since wardening began in the mid 1980's. The gull continued on travelling north as soon as it had finished with the tern so I wouldn't be too worried about it as it appears to have been an opportunistic one-off event (although I have since been giving all the gulls migrating past the colony the old evil eye!).

DON'T PANIC!!! I think it's time for a bit of positive news for a change! With regards those nest lost to the Rook, well it's still early enough in the season for them to re-lay and it appears that some of them are already beginning to do so (it generally takes 7-10 days after predation for a re-lay to appear). Furthermore there was an arrival of about 20 new birds at the colony early last week & they too have settled down to breed with quite a few new nests found over the past couple of days. As such we currently have 50 active nests with 101 eggs so we're making up for lost nests in no time! With any luck there'll be a run of new nests (hopefully involving those re-lays) over the next week. We're also expecting our first chick to hatch any day now too! There's a couple of nests which have eggs with cracks on the shell so there's obviously a beak poking at it from the inside! My money is on the first chick hatched tomorrow in nest K6.

K6 eggs on the brink of hatching. Cracks in the shell visible & all! © Niall Keogh
Volunteers Siobhan & Riona with warden Jason fixing up some chick shelters which are due to go out today! © Niall Keogh 



Little Terns in evening light © Niall Keogh


Things had quietened down for a while on the bird front with the best of the action last week again at sea during the high winds when decent numbers of Manx Shearwaters were noted (e.g. 1,500 heading south in an hour & a half on 25th) with some Storm Petrels knocking about too, 4 Common Scoter heading north on 27th and up to 4 Great Northern Divers & 2 Red-throated Divers also loafing offshore. A Balearic Shearwater heading south with the Manxies on 25th was quite early & a great local record of this Critically Endangered seabird (more on this species in the coming weeks - watch this space!). 

The feral Barnacle Goose made a reappearance in Webb's field on 25th, a pair of Shoveler were seen in the area with 6 young recently which is an excellent breeding record for this species & a pair of Teal are also present but don't seem to have bred. The Breaches estuary outflow was blocked for a few days after a southerly wind but as soon as it was opened the waders began to arrive. Yesterday saw some particularly nice movements of species like Sanderling (22), Knot (2), Bar-tailed Godwit (2), Black-tailed Godwit (5), Dunlin (13), Turnstone (8), Curlew (1) & Whimbrel (13). Other migrant species recorded in recent days include an adult Arctic Tern passing through on 28th, a 1st-summer Little Gull & 3 Mediterranean Gulls moving north yesterday afternoon & best of all a super close, low-flying Osprey with a whole gang of raucous Oystercatchers & gulls in attendance, heading slowly north over The Breaches yesterday evening at 19:30!!! An great bird which myself, Jason & Cole all got to see as well as two other birders who raced up to Killiney Hill in south Dublin and caught it moving inland over Bray & Shankill half an hour later! 

There's also a pair of Cuckoos hanging around the Sea Buckthorn bushes in recent days which have attracted a lot of attention from members of the public who are enjoying great views of these rather tame birds. The flip side of this however is that the Cuckoos are spending quite a bit of time feeding on caterpillars along the path by the K-colony & inadvertently spooking the terns as a result (the terns think the Cuckoo is a bird of prey it would seem which is fair enough as they look a bit like a mix of Sparrowhawk & Kestrel in flight!). Saying that, this has meant we've been getting good flock counts on the Little Terns with 114 adult birds seen yesterday!

Cuckoo on the K-colony fence © Niall Keogh
The 3 Bottlenose Dolphins & the Otter continue to be seen regularly & showing well too. The dolphins were jumping around all over the place yesterday evening really close offshore from the K-colony which was great to see!

Anyways, there should be a flurry of new nests & chicks hatching over the next 2 weeks so why not pop down for a visit?

Until next time!

Niall