It is very disappointing to
report that once again (just like in 2007, 2008 and 2011), the Channel Islands’
most important colony of Lesser Black-backed Gulls has failed to produce many
chicks. Our annual monitoring and ringing trip this year managed to locate and
ring just 29 chicks from the 1,200 pairs of LBBGs nesting on Burhou, Alderney.
We cannot (yet) be sure of the cause, although it seems most likely that this
is an acute shortage of food. Further work is needed to establish the causes.
With the annual recruitment into the colony so low in many years, it is
difficult to see how the colony is going to sustain itself, and it is perhaps
inevitable that within a few years we will see colony declining. On a slightly
brighter note Herring Gulls this year on Burhou appear to have nested
successfully, and there was also a threefold increase in breeding numbers from
five to 15 pairs.
Wednesday, July 17, 2013
Monday, July 15, 2013
The Greatest Journey Ends Where it Began.
Last weekend, with the help of
the Alderney Wildlife Trust, I made my annual visit to Burhou to monitor the
breeding success of the Lesser Black-backed Gull colony (c 1,200 pairs). This is the first of several postings I will
make resulting from that visit.
In the main gull colony we found
a freshly dead Lesser Black-backed Gull (no sign of predation or oiling or
being hooked or caught in fishing line). The bird’s posture indicated that it
may have been killed in a territorial fight with another LBBG. Turning the bird
over, we saw the colour ring - Black 6.T5. This gull had been ringed as a chick
on Burhou in July 2010. It fledged successfully and was recorded at Quarteira
Beach in the Algarve, Portugal that October by Michael Davis. Unlike most of
our young gulls it did not however stay in Iberia, it continued into Africa and
was recorded on 15 February 2012 at Tanji Bird Reserve in The Gambia by Clive
Barlow. To date this is the most distant migration of any Lesser Black-backed
Gull ringed in the Channel Islands (a straight line distance from Burhou of
more than 4,250 km!). Although it is marvellous to know that this young gull
did make it all the way back to its natal colony, where it would most likely
have first bred this year or more likely next, I am really disappointed that
this great traveller is dead.
LBBG Black 6.T5 Quarteira October 2010 (c) Michael Davis
LBBG Black 6.T5 in illustrious company at Tanji Bird Reserve, The Gambia February 2012 (c) Clive Barlow
The ring from LBBG Black 6.T5 freshly dead on Burhou 12 July 2013 (c) PKV
The Movements of LBBG Black 6.T5
Sunday, July 14, 2013
LBBG in its 20th Year
Phil, Carolyn and I took another modest gull catch in the garden today. Amongst the five LBBGs caught was E5849, which I ringed as a chick in one of the Sark colonies in July 1994. This wonderful old gull has just entered its 20th Year. It now carries colour ring Black 9CC4.
LBBG Black 9CC4 entering its 20th Year (c) PKV
Thursday, July 11, 2013
The Gulls They Are A Fledging!
It was wonderful to see so many young gulls...the Class of 2013...beginning to fledge on Lihou today. Several were already confident on the wing, while many were with their parents in the inter-tidal zone. It's many years since I've seen so many young gulls at this time of year. The next few weeks will still be critical for them...but it looks like a pretty good season for productivity in both Herring Gulls and Great Black-backed Gulls - the best for at least five years...and probably longer. Credit must got to the States Environment Department both for controlling rats on the island over the past two winters (there is strong evidence that the presence of rats in seabird colonies significantly decreases productivity) and also for roping off the sensitive nesting areas on the island during the breeding season.
Back to the Landfill!
It seems like ages since I was last able to enjoy some ring reading at Chouet landfill, so it was extra special to be able to record for a couple of hours this morning. Some 220+ ring reads were taken (c 150 LBBG and 70 Herring Gull with a very few GBBG). Within a month now the adult LBBGs will start migrating south again - marking the beginning of the end of summer!
Monday, July 8, 2013
Roof Nesting Gulls Still Rare in Guernsey
I've commented several times before on this blog about how rare it still is in Guernsey for Herring Gulls to nest on roofs. At present the birds continue to nest at traditional sites on the Island's cliff coastline and offshore islands and islets...and long may it remain so! A handful of Herring Gulls (but not yet any Lesser Black-backed Gulls to my knowledge) buck this ancient trend...and have begun to nest on domestic roofs...but they are very few and far between. Each year I only get to ring one or two chicks from such nests. I'm always keen to colour ring these chicks to see if they adopt their parents nesting habits or return to the islets or cliffs when they are old enough to breed (by their 5th calendar year). Today I ringed the only chick from a roof nesting pair I've seen this year - White 2HV9. The parents are most fortunate in that their human hosts feel privileged to have the birds nesting on the roof...despite the mess and the noise!
Herring Gull White 2HV9 - a rare roof nesting gull in Guernsey! (c) Pat Costen
Sunday, July 7, 2013
Highlights of Another Good Gull Catch
With the 2013 summer gull ringing season entering its final phases, Phil, Carolyn and I took another excellent catch in the garden today. Among the highlights of the 75 gulls caught were another nine Lesser Black-backed Gulls (eight new birds) and Herring Gulls which had originally been metal-ringed as chicks on Sark in 2006 and Jethou in 2008.
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