Guernsey Gulls March 2009

 

 
The year continued in very fine form, with much valuable data on Bailiwick gulls being gathered. The month was characterised by the return in force of our breeding Lesser Black-backed Gulls (Larus fuscus graellsii) from their wintering grounds, by the onset of courtship activity amongst local Herring Gulls (Larus argentatus), and by the dispersal of many of the Great Black-backed Gulls (Larus marinus) that had spent at least a part of the winter in Guernsey. It has been amazing to study these three species in March – all of which have revealed interesting aspects of their migratory and/or breeding ecology.

A great deal of effort has been made this month to visit Chouet landfill, and the beaches in the north of Guernsey, both to monitor the arrival of our returning Lesser Black-backed Gulls, and to record what was happening with our Herring and Great Black-backed gulls.

Over the month visits were made to look for colour rings at Chouet landfill and/or Pembroke, Chouet and Chouet landfill beaches on 28 days – resulting in a grand total of just over 500 ring reads as follows:-

Herring Gull                                      430

Lesser Black-backed Gull              64

Great Black-backed Gull                 10

Lesser Black-backed Gull

Perhaps the highlight of a very interesting month for me was the re-sighting of another seven (making a total of nine so far this spring) out of 16 adult LBBGs that I ringed in my garden at Ty Coed, Guernsey in May/June/July  2008. Not one of these birds was present in Guernsey over the winter. The great value of colour ringing (over simple metal ringing) was demonstrated by the fact that of this tiny sample of gulls, two had been seen in Iberia over the autumn/winter period.

 The return dates for these nine gulls were: -

            14 February                               7S5

            20 February                               7S6*

            03 March                                    7S0 *

            03 March                                    0Z1

            07 March                                    7S1

            11 March                                    7S3

            11 March                                    7S4

            19 March                                    7S2

            23 March                                    0Z6

 *7S0   had been seen on 22nd August 2008 at Meiras Beach, Valdovino, Spain by fellow gull enthusiast Antonio Gutierrez.

* 7S6   had been seen on 21st August 2008 at Pantin Beach, Valdovino, Spain by Antonio Guteirrez, and at Matosinhos, Portugal by Peter Rock on 28                     November 2008.

 This sample is of course too small to be representative of adult survival rates, and there is time yet for more to be located. It will be very interesting though to see what the final tally will be. (P.S. 6S7 arrived back on 1st April, and 0.Z7 on 3rd April)  – so we are now up to 11 out of 16 gulls back – only five more to find!).


 In addition to sighting these nine of “my” gulls, I was thrilled to record no fewer than eight LBBGs that had been colour ringed elsewhere. It was very clear that several of these birds were on spring passage, for they did not linger at Chouet Landfill on the north coast of Guernsey. The following gulls are such examples:-

  1. White D:J  ringed as a chick in Bristol, England  in 2003 by Peter Rock, and seen at Matosinhos, Portugal in September 2007, and at Valdovino, Spain in August 2008 (as well as several sightings back in the Bristol area)  before being seen at Chouet landfill on 5th March.

  1. Black W9XD ringed as a chick at South Walney Nature Reserve, Cumbria, England in July 2002, and seen at Barra, Portugal in November 2005, before being seen at Chouet landfill on 21st March.

  1. Black R6DD ringed as a chick on the Ribble Estuary, Lancashire, England in June 1999. Incredibly it was not recorded again for almost a decade, then it was sighted twice in 72 hours as follows: - at Frouxiera Lagoon, Valdovino, Spain (Antonio Gutierrez) on 25 March and then three days later at Chouet Landfill.

4.     Blue JU4A ringed as a chick near Mandal, Vest-Agder, Norway in July 2003, before being seen again in Vest-Agder in May           2005, Earsham, Norfolk, England in August 2006, in Rogoland, Norway in May 2008, before being seen at Chouet landfill        on 28 March.

 The movements of other Lesser Black-backed Gulls seen were less easy to interpret. In particular several that had originally been ringed as adults at the landfill sites near Gloucester, England, and which I had subsequently seen at Chouet, surprised me by re-appearing in Guernsey after several weeks’ absence. My suspicion that in most of the cases the birds had left Guernsey is backed up by the re-sighting of one of the birds back at Gloucester in the intervening period before it returned to Guernsey.

It will be fascinating to see if the birds below remain in Guernsey as the breeding season draws on. Perhaps they are in fact Channel Islands nesting gulls that have wandered north to winter in the UK, rather than English-nesting gulls that are using Guernsey as a staging post in their return migrations?

  1. Blue 956 ringed as an adult at Gloucester landfill, England  in October 2005, before being seen at Ouessant, Finistere, France in February 2007 and then back at the landfill sites around Gloucester, England in October 2007. I first saw this bird in Guernsey on 22 January 2009 (at Vazon Bay). I did not see it again until 16 March at Chouet landfill.

  1. Blue ACE ringed as an adult on 11 November 2006 at Glocs Landfill, England, before being re-sighted at the Glocs landfills in November 2007, and October & November 2008. I first saw this bird at Chouet landfill on 14 February. It was not seen again in Guernsey until 28 March!

  1. Blue CHN was ringed as an adult in November 2007 at Glocs Landfills, England. I then saw it at Chouet Landfill, Guernsey on four occasions between 17 February and 09 March. On 11 March it re-appeared at Gloucester Landfill, England – only to return to Guernsey by 21 March (so far I have seen this bird daily at Chouet until 27 March).

  1. Blue ATN ringed as an adult at Stoke Orchard Landfill, Glocs, England in February 2007. It was sighted at the Glocs landfills in December 2007 and February 2008. It appeared in Guernsey (at Chouet landfill Beach) on 17 March. This gull has been re-sighted virtually daily to 31 March.

 Although I have witnessed the spring return of Lesser Black-backed Gulls in Guernsey for several decades, I am embarrassed by how unobservant I have been in previous years. In 2009 I hoped to monitor the spring migration by making a daily count of LBBGs at Chouet (both in the landfill and on the beaches of Pembroke/Chouet and Chouet landfill Beach – all at the northern tip of Guernsey).

 This aim has been severely hampered by the fact that I have so few of our local breeders colour ringed. It is therefore proving to be impossible to determine the proportions of locally breeding birds to passage migrants. An overall count is of some value, but I know that the few locally colour ringed birds do not all visit the area all at the same time. Their attendance can be spread over different parts of the day, and even over different days. I hope that by the spring of 2010 I will have a much larger sample of Bailiwick breeding adults colour ringed – thus making it easier to identify the proportions of migrants on any given day.

 What is clear is that the numbers of LBBGs build very quickly from early in March. On 2nd March my maximum count was 90 LBBGs. This had increased to 120 birds on 4th, with 230 the following day. Numbers did not reach the 300 mark until 16 March, and by 21st 380 were counted. On 24th there were 400 LBBGs present, and the month ended with 450 birds present.

 I had expected that the vast majority of LBBGs seen in Guernsey in the spring will be from the race Larus fuscus graellsii which nests (inter-alia) in Britain, Ireland and Iceland. Notwithstanding this, I was surprised at how few Larus fuscus intermedius I saw – in fact I was only convinced of seeing a single adult.

 By the week commencing 23rd March, it was commonplace to see LBBGs in courtship behaviour – both on the beaches and in the landfill site. A few pairs were also observed copulating on 31st March – so the 2009 breeding season is clearly underway!

 One final area of interest has been trying to read metal-ringed Lesser Black-backed Gulls. This is really a “mug’s game” because it is very difficult – and requires huge patience. Even when you can see the digits on a ring through the telescope, you have to be able to see all the way around in order to get the whole unique code. Notwithstanding this I am spurred on by the sight a reasonable number of adult Lesser Black-backed Gulls which carry metal rings. Over the month I managed to read seven Channel Islands metal rings, and they have given some valuable data for my projects. Of these birds two were originally ringed on Brecqhou, Sark in 1990 and 1994, while four were from Burhou, Alderney (1991, 1992, 1993 and 2006). All of these birds were ringed as nestlings. One adult ringed in the summer of 2006 in our garden at Ty Coed (one km from Chouet landfill) was also seen.

 In addition I enjoyed the bonus of reading two British metal rings (one only partially, but the code is narrowed to a string of 100 rings – so it may at least be possible to know where this bird was ringed and in which year). Details for these two rings are currently awaited.

Postscript - details of the complete British ring read are as follows:-

London GG 67002 - Ringed as a nestling on the Isle of May, Scotland on 20/07/90  and sighted at Chouet Landfill Beach, Guernsey on 26/03/09 - a distance of 743 km south and a time lapse of 6,824 days.

 Herring Gull

With so much interesting activity taking place with Lesser Black-backed Gulls (my primary study species), it would have been easy to overlook what has been happening with Herring Gulls in Guernsey. Fortunately this has not been the case, and our Herring Gulls have revealed some interesting ecology too.

Having made regular visits to Chouet Landfill since August 2008, one might have expected that I would have recorded nearly all of the surviving Herring Gulls colour ringed by Jamie Hooper over the period 1998-2007. The sighting of 22 of Jamie’s gulls for the first time in March is strongly suggestive that these birds have been off-island at least since August 2008. Indeed the sightings history of some of these newly sighted gulls confirms this (see below –all were ringed as nestlings in June/July).

  1. 2J4 ringed in 2001 and sighted in Cherbourg, France in August 2003 and February 2006 before being seen at Chouet landfill on 13th March.

  1. 9F2 ringed in 2001 and seen on migration at Les Sables d’Olonne, Vendee, France in February 2002 and January 2004, and on its wintering grounds at Ile d’Oleron, Charente-Maritime, France in November 2001, October 2003, September 2004 to Jannuary 2005, September 2007 and October 2008, before being seen in Guernsey at Chouet Landfill Beach on 10th March.

  1. 4N8 ringed in 2005 and seen at Noirmoutier Island, Vendee, France from July to mid-September 2007, before being re-sighted back in Guernsey at Chouet Landfill on 7th March.

     4.      6K6 ringed in 2003 and seen at Rogerville, Seine-Maritime, France in December 2003, before being seen at Chouet landfill on           5th March.

     5.   3L5 ringed in 2002 and seen at Marais d’Olonne, Vendee, France before I saw it at Chouet landfill on 5th March.

    6.      4M7 ringed in 2003 and then seen in Bristol, England  on 8th August 2003, and from 26th August to 12th September at                     Gloucester Landfill, England before being seen at Chouet Landfill Beach on 22nd March.

  1. 0P6 ringed in 2004 and seen at Radipole, Dorset, England in July 2007, and then on 9th January 2009 at Champteusse-sur-Baconne, Maine-et-Loire, FRANCE (by Alain Fosse) before being seen at Chouet landfill on 30th March.

Pride of place, however, must go to the following two long distance travellers – both of which have spent time in Iberia before returning to Guernsey.

  1. 0P0 ringed in 2005, and seen at Ares Beach, A Coruna on 18 January 2007, before moving east along the Spanish coast to Aviles where it was seen on 19th March 2008. I was very excited to see this bird back in Guernsey at Chouet landfill on 14th March. It is presumably going to breed in the Bailiwick of Guernsey
  2. 7M6 ringed in 2003 and seen at Douro River, Portugal in November 2003, and at Matosinhos, Portugal in November 2004, before being sighted in Spain at Getxo, Basque from 6th-12th March 2006. It was then sighted at Lemoiz, Vizcaya, Spain from 22nd August to 14th December 2007, and again on 19th January 2009, before returning to Guernsey where I saw it at Chouet Beach from 22nd March.

In addition to these movements I also recorded one foreign colour-ringed Herring Gull – from the south-west of England.

White G:C ringed as a nestling (female) in Gloucester, England in July 2007, seen from 6th to 11th March 2009 at Chouet Landfill, Guernsey, before being re-sighted at Gloucester landfill, England on 18th March.

Details were also received for the French-ringed Herring Gull seen at Chouet landfill on 26th February 2009. Pale Blue 113 was ringed as a chick at Le Havre, Seine-Maritime, France on 2nd July 2008. It was then seen at Trouville-sur-Mer, Calvados, France on 17th September 2008.

Again the colour ringing is making it possible to follow the lives of individual gulls in a very unobtrusive manner – revealing much fascinating information about their movements.

 As well as these Herring Gulls, seen by me for the first time, it was also interesting to re-sight a number of birds which I had not seen since the autumn of 2008. Again, I believe that most of these birds will have left the island over the winter period, only to return now in the spring to breed.

 In all I saw 172 of Jamie’s Herring Gulls during the month (418 sightings) , as well as 12 of mine (37 sightings) (ringed in late 2008/early 2009).


Great Black-backed Gull

As expected there was evidence of passage of Great Black-backed Gulls at the north end of Guernsey during the month. Until I commence my own colour ringing project on this species in the summer of 2009, it is impossible to follow the movements of local breeding population, as opposed to migrant birds. However, the further sightings of gulls originally ringed at Le Havre, Seine-Maritime and from the Chausey Islands, France backs this up.

 In fact, it is interesting that a number of the French-ringed gulls were re-sighted in March- having not been seen in Guernsey for a number of weeks since their last sighting here (see below).

  1. Blue 30C ringed at Le Havre, France  in June 2007, and first seen in Guernsey at Perelle on 18 September 2008. I saw it several times up to 27 September, but there were no sightings over the entire winter period, before the gull was seen on ten occasions at Chouet between 10th and 31st March.

  1. Blue 47D ringed at Le Havre, France in June 2008 and seen at Chouet, Guernsey on 5th and 8th February 2009, but then not again until 8th-11th March.

  1. Blue 74C ringed at Le Havre, France in June 2008 and seen first at St Peter Port harbour, Guernsey on 29 September 2008 – then on 19 November 2008, 29th January 2009 and 12th March 2009 at Chouet Landfill Beach.

  1. Blue 94C ringed at Paleul, Seine-Maritime, France in June 2008 and seen first at Rousse, Guernsey on 4th December 2008 – then at Chouet Landfill on 5th February and 4th/5th March 2009.

  1. Green B.09 ringed at Huegenants Island, Chausey, France in June 2008, and seen at Chouet landfill on 29th January 2009, then twice in February and from 10th- 27th March.

  1. Green B.88 ringed (presumably) in Chausey Islands, France in summer 2008 (exact details currently awaited) – and then seen for the first time at Chouet landfill, Guernsey from 14th-19th March 2009.

9th  International Gull Meeting – Peterhead

I mentioned in the February Guernsey Gulls News that Catherine and I had been pleased to attend the 9th IGM at Peterhead, Scotland which had very kindly been organised by Dr Chris Gibbins of Aberdeen University. Unfortunately I have not been able to find a way to load my presentation on “The Changing Fortunes of Gulls Breeding in the Channel Islands” onto my web site. I can, however, include a photo of the participants.

 

Scarce Gulls in Guernsey

The only unusual gullsrecorded this month were an adult Mediterranean Gull on 1st at Cobo Bay, and an adult Common Gull on the beach at Pembroke on 19th.

                                                                 © Phil Alexander

4th April 2009