Burhou, Alderney

12 & 13 June 2009

 

Paul and Catherine Veron set off for Alderney on the 5.45p.m. Blue Islands flight to Alderney on Thursday 11th June with the aim of colour ringing as many adult Lesser Black Backed Gulls as possible on Burhou.   The two ringers were met at Alderney Airport by Afra Skene, the Alderney Wildlife Trust ecologist who provided an excellent escort for the rest of the visit.  After a delicious fish and chip supper a comfortable bed was sought out and provided at the Alderney Wildlife Trust’s Essex Farm.

An early start the next day in order to cross the Swinge in the Alderney Wildlife trust’s new rib saw all three safely landed on the island by 8.00am.  We were soon trapping adult Lesser Black-backed Gulls, fitting a metal ring, colour ring and measuring the head and bill length so that we could determine the sex of the birds. Finally a photograph of all gulls was taken for recording purposes before they were released.  Most sessions resulted in at least one capture with the occasional run when five gulls were caught at the same time. The team conjectured that the timing of the visit was perfect. 

In order to regulate disturbance, once the area behind the hut was worked four times (each time moving through the colony), the team moved onto the gull breeding area in the south central part of the island.  This large area of nesting proved very fruitful although it was difficult to catch birds in tall vegetation. The team worked through the colony, ringing the birds on the beach out of sight of the nesting birds.  By 5pm they had reached the west side of the island and with the tide at its lowest, they made a short sortie across to Little Burhou to look for nesting Shags.  A total of 28 shags were ringed and it was noted that the Cormorants had been successful although now all were too large to ring.  Two small sub-colonies of Lesser Black Backed Gulls (totalling up to 100 pairs) were breeding on the small islet. A Common Buzzard was also seen harassing this gull colony (and again on the Saturday) – presumably looking for any stray pulli although rabbits were plentiful on Alderney albeit in short supply on Burhou.

The team returned to Burhou after ¾ hour and carried on searching for Shag pulli but most were either inaccessible, too small or had failed on Burhou. Four chicks were ringed.

After a reasonable night’s sleep in the hut, the team returned to the far west end of the island to continue the Lesser Black Backed Gull ringing.  The same formula was adopted of ringing on the beach until the team was close enough to the hut to be able to use it as the base.

A total of 67 adults were caught over the day and a half, which should provide very valuable data for Paul’s gull research for many years to come.  Three metal ringed adults were also retrapped – all had originally been ringed on Burhou as follows –

E 12327 adult male caught on 12th June – originally ringed as a nestling on Burhou on 19th July 2003

E 12420 adult male caught on 13th June – originally ringed as a nestling on Burhou on 19th July 2003

E 5666 adult male caught on 13th June – originally ringed as a nestling by Paul on Burhou on 6th July 1993.

By noon all the Gull ringing had been completed and a short nesting survey of the main Lesser Black Backed Gull colony in front of the hut was carried out by the team, utilising pasta shells to mark the counted nests.  A total of 502 active nests with either eggs or young were recorded.

The team packed up their gear and then waited for their pick up from the rib at 1.30pm.  A short delay was necessary whilst a technician visited the hut to switch over batteries for the Puffin Webcam.

The ringing team was delighted with the results of their visit and pleased to see the Burhou’s Lesser Black-backed Gulls doing so well – especially after the virtual complete failure of the colony in 2008.

 

Catherine Veron

16/6/09