Burhou, Alderney

14 & 15 July 2011




Having kept a close watch on the five day weather forecasts all week, I changed plans and went up to Alderney a couple of days earlier than planned to visit Burhou to assess the breeding season for Lesser Black-backed Gulls. This was a wise move, given the dry, calm weather on 14 and 15 July, which was followed by yet more wet and windy weather over 16-17 July! I got the first Aurigny flight up to Alderney at 0745.  As we approached Alderney there was a thin, beautiful white mantle of puffy mist hanging over the west end of the island. As a result we circled the island several times, and made one aborted effort to land. This gave superb aerial views of the harbour and Burhou, which were bathed in sunshine. It was only ever going to be a matter of time before the mist burnt off, and after several circuits we came in again and touched down in clear blue skies – a fine example of the vagaries of island weather! 

Liz Morgan, the Alderney Wildlife Trust Ecologist, was very kindly waiting at the airport for me. After a quick visit to the supermarket to pick up some supplies we were soon heading for the harbour with the AWT’s Rib “Sunrise” in tow.  Once again I am grateful to Roland Gauvain for kindly arranging this and taking us over to Burhou. We had a superb calm and fast run out across The Swinge to the islet. 

It felt absolutely wonderful to be back on the island…although I already knew from Liz’s reports from the previous week that there appeared to be very few gull chicks on Burhou this summer. Most of the adult gulls appeared to still be present, although it was a worrying sign to see many of them loafing on the grassy ridge slope as we walked up to the hut. 

Once I’d sorted out my ringing gear, Liz Morgan, Lyn …. and I set off to check the whole island for gull chicks. We started at the hut…where not a single chick was found. Working down checking the bracken and the beach along the south coast no chicks were seen! Only when we got into the main colony at the west end did we manage to find a few Lesser Black-backed Gull chicks (eight in total). They were exactly the size I would have expected at this time of year – perfect for taking colour rings. A couple were large – and I did see one fully fledged Lesser Black-backed Gull chick. 

The lack of any serious mobbing by the adult gulls confirmed our suspicions that the colony had suffered a mass failure. When I visited on 11-13 June 2011 the colony was in very good shape, with adults incubating eggs. At that time everything looked very normal. However…as elsewhere in the Bailiwick of Guernsey this year, I think several days of unseasonably cool, wet and windy weather at the critical time when most of the LBBG chicks would have been hatching has been the primary cause of this widespread failure. 

The Guernsey Met Office has confirmed that June 2011 was the coolest here in Guernsey since 2002 and also the windiest for 20 years. There were also many more day so of rain this year (than last) with precipitation at some stage on every day from 07 to 21 June. Guernsey Water also reports 22% more precipitation in June than the monthly average during the previous decade. Some 2.1 inches  (53.3 mm)  of rain fell on Guernsey during the month. This unusually wet and windy weather may well explain the widespread breeding failure of Lesser Black-backed Gulls across the Bailiwick of Guernsey this year.

What is particularly disappointing is that this is the third known mass failure of the Burhou Lesser Black-backed Gulls in the past five years – with only 2009 and 2010 being productive years for them. 

Herring Gulls continue to decline on Burhou. There must have been far fewer than 100 pairs this year – and we only found six chicks to ring. Only one Great Black-backed Gull chick was found on Little Burhou (although one other 2011 fledgling was seen in flight). As elsewhere in the Bailiwick, European Shags appear to have done well this year, with many fledged young seen around the shoreline, along with a smaller number of Cormorants.

 Liz told me that some of the Puffins had already left – in what has proved to be a very early year for their breeding.  Just over 100 adult Puffins could still be seen rafting in front of the hut, including several birds bringing Sandeels ashore (so they must have still been feeding chicks). A pair of Peregrines has been seen frequently on Burhou his summer, and their young are now joining them in flights around the island.

 Late one evening Liz and Lynne undertook a playback survey of the wall in front of the hut, discovering a minimum of 23 Storm Petrels nesting in the wall.

 Given the failure of the gull colony this year, I did have the time and the opportunity to search through the adult gulls looking for my colour ringed birds. I was thrilled to find no fewer than 130 of my Lesser Black-backed Gulls which had original ringing details as follows:-

 1992 (one), 2003 (two), 2005 (one), 2008 (one from Burhou and one from Guernsey), 2009 (43 adults plus three of the chicks ringed in 2009 which are now back prospecting Burhou for future breeding, plus three from Guernsey), 2010 (28) and 2011 (37 plus seven from Guernsey). Just over 30 of these birds had been reported outside the Channel Islands last autumn/winter (mostly in Iberia, but some in France and England). I also recorded Black 3.N6, which is the adult Lesser Black-backed Gull ringed in June 2010 which I saw at Anza, Agadir, Morocco in December 2010! Amongst the colony again this year were the three birds seen in 2010 which had been colour ringed at Gloucester landfill in 2004, 2007 and 2008 respectively. 

In addition I recorded seven of my cr Herring Gulls (all ringed originally on Guernsey) and one Great Black-backed Gull – seen only 100 metres from where it was raised on Little Burhou in the summer of 2009!

 Once again there was a very beautiful sunset on Burhou, and a pretty moonrise too over Alderney. While this had been a very disappointing trip in terms of the sheer lack of gull chicks, it had been marvellous to be able to record so many of my adult gulls, and to observe my favourite bird (Lesser Black-backed Gull) at close quarters in its breeding colonies, before the season draws to a close and they start drifting off again.

 We can only hope that 2012 sees the important colony of Lesser Black-backed Gulls being successful and productive once again.



 

 

 

PKV

18 July 2011