Burhou, Alderney

13 - 15 July 2012



My two most important birding activities of each year are the week’s gull cannon netting with Paul Roper and members of the North Thames Gull Group at Chouet landfill, and the visit to Burhou in July to ring gull chicks. Since 2008, I have learnt that the latter can sometimes be disappointing because all too frequently there are years (such as 2008 and 2011) when the breeding productivity of the 1,000 pairs of Lesser Black-backed Gulls on Burhou can be negligible or extremely poor. Given the very poor summer so far this year, with many many days of rain and strong winds I feared that 2012 would also be a disastrous year for gull productivity in Alderney. In fact the weather has been so bad that for several weeks it looked very dubious that we would even be able to land on Burhou to undertake the monitoring. In the end I took a chance and went for a very small and difficult window over the weekend of 13 – 15 July. Although four or five days later than the visits made to Burhou in the previous four years, the timing should still have been good…and so it proved!

Chris Mourant and I caught the new Bumblebee boat service up to Alderney on the Friday afternoon. We were the only two passengers on board, and we enjoyed a very comfortable and swift crossing up to Alderney. James Allison, the AWT Ecologist, was at the harbour waiting to pick up all our gear. There was time for a fish and chip supper before Dave Venn picked the three of us up in the AWT’s new boat (Sula of Braye) for the crossing to Burhou.

Fortunately the weather was a little better than forecast and Dave even managed to bring the boat alongside the gulley making a very simple landing. A very nice raft of c 200 Atlantic Puffins were in the bay to the north of the hut.

No sooner had we entered the hut than it began to rain rather heavily…so any thoughts of ringing a few gull chicks were cast aside. As we had walked to the hut it was very clear from the gulls’ behaviour that a reasonable number of them were still in breeding mode. This was in contrast to our arrival in July 2011, when the gulls showed very little interest in our presence, and many were simply loafing on the grassy slopes. We even saw a few well-grown chicks on the rock outcrop by the hut, which gave even further encouragement for a successful day’s work in the morning!

Overnight the rain was both persistent and at times torrential…but fortunately before dawn it had cleared, giving way to an overcast, breezy but warm day. After breakfast, James, Chris and I set off on our day’s work. We began, as usual, entering the gull colony just to the south of the hut and then working all the way around clockwise to reach the north-western edge of the colony by late afternoon. In between there were several breaks for refreshments and to boil fresh water to make the colour rings more pliable.

It was such a joy to be finding gull chicks again. Chris and James did a fantastic job at locating and metal ringing the chicks hiding in the bracken. It was all I could do to keep pace fitting the colour rings, recording the details and photographing the majority of chicks ringed. The chicks were an ideal size for ringing being large enough to take colour rings, but not so big that they were mobile or flighty. In fact the dates were just about perfect!

The small team worked very efficiently and well together. By the end of the day both Chris and I were feeling the pace with our backs aching from all the stooping and bending, while James being so much younger took it all in his stride!

By the end of the day we had ringed 199 Lesser Black-backed Gulls (198 with colour rings). While this was less young ringed than in several recent years, I was absolutely delighted with such a total achieved in such a difficult year (both for the gulls in raising the chicks and for us in trying to reach Burhou!). A very crude productivity figure would be 0.2 chicks per pair…but this must be a significant underestimate because some of the pairs were still incubating or with very tiny chicks. Presumably the majority of these were re-laid clutches for nests which had been lost earlier due to the wet, cool and windy weather? Furthermore we cannot find every gull chick, as they are very adept at hiding in the bracken.

I felt deeply contented by the time we retired for a bite to eat and some sleep. The following day we covered the small gull colony along the north coast…but found only a couple of LBBG chicks here to ring. We also crossed to Little Burhou, where we found four Great Black-backed Gull chicks to colour ring, along with only our third Herring Gull chick of the trip! It is remarkable to see how scarce Herring Gulls have become as breeding birds on Burhou – a far cry from the situation in the 1980s and 1990s when many of the rocky knolls were dominated by Herring Gull colonies and there were more than 100 pairs breeding on the island. Only a handful of Herring Gull chicks were raised on Burhou again this year…which must bode very badly for the future for this species on Burhou.

Great Black-backed Gulls also seem to be declining on Burhou, with only one large chick seen on Burhou and four ringed on Little Burhou. Probably because of the few chicks around the GBBG predation of other gull chicks seem to have been light this year.

On this visit to Burhou there was not a lot of time for trying to record colour ringed gulls, but I did manage to get out with the telescope and record 21 LBBGs and three Herring Gulls, many of which were back from wintering in Iberia. Last year with many of the birds having failed in their breeding attempt it was far easier to record more cr birds as they stood loafing about on the rocks. With continued breeding activity this year, many more of the gulls were still busy in the colonies where the long vegetation makes ring reading extremely difficult.

The nearby pair of Peregrines continue to take adult gulls (both GBBGs and LBBGs), in addition to other avian prey. At least two chicks appear to have been raised this year.

A flock of 11 Whimbrel caused some debate…were they late spring birds heading north, or early autumn birds heading south – surely the latter? A pair of Shelduck was seen on the island, as well as a very healthy population of Rock Pipits. The Atlantic Puffins also seem to be doing well…at least holding their numbers just over 150 breeding pairs. It has proved very difficult (because of the weather) to monitor productivity this year.

The final totals of gull chicks ringed were as follows:-   203 LBBGs (all but one colour ringed), four GBBGs and two Herring Gulls.

On cue on Sunday at mid-day Dave reappeared to pick us up. With the wind picking up again the swell was building again, and so we used the dinghy to row out to the AWT boat. We were back on Alderney in time for lunch at the Little Rock Café. Of course this was very handy for checking the gulls loafing on Crabby bay after bathing in the freshwater quarry next to the electricity station. Before and after lunch I managed to record another 11 ringed LBBGs here, including several chicks form 2009 which are clearly now back visiting their natal colony on Burhou before their first breeding attempts in the years ahead.

During the afternoon the wind continued to make and just as Chris and I were enjoying an early supper we got a call to confirm that Bumblebee had cancelled the service from Alderney back to Guernsey at 1900 hrs. Chris and I therefore stayed at the AWT hostel for the night, and with no let up in the wind forecast for the following day, we booked seats on the first flight back to Guernsey in the morning.

For Chris and I this was now a consecutive hat-trick of extended stays in Alderney – the first caused by mist at Alderney Airport, the 2nd by a 24 hour delay in getting off Burhou and now the 3rd by rough seas and a cancelled boat service. This is just a reflection of the sort of weather we’ve been having lately!

In difficult circumstances, it has been a real highlight of the year for me to be able to get to Burhou to colour ring LBBG chicks. I can now look forward to following some of these gulls south on holiday later in the year…where I hope to find a few of them in Portugal..and maybe even further south!

 

 

 

 

Paul K Veron

 
19 July 2012