Monday, 5 September 2016

Kittiwakes from France

This summer has seen an incredible influx of Kittiwakes to the coast around Bardsey, with flocks numbering into triple figure counts frequently alighting into the air like snowflakes! Here on the island, we often have flocks of mixed adult and juvenile Kittiwakes lounging around the coast in July and August, often settling on particular stretches of the shore. However, this year has seen consistent high numbers from around 20th July through to the end of August. Some of our highest counts have included 3266 on 21st August, 2100 on 31st August and 2000 on both 25th and 27th. Although these mega counts have been amazing, it is more the consistent daily gatherings of 600+ that have made for an impressive sight throughout August -  significantly higher numbers than previous years.

On the occasions when myself or staff from Bardsey Bird Observatory have been close enough to a settled flock to see, it has been really cool to pick out plenty of colour-ringed birds amongst them. Looking out for colour-ringed birds is a great way of contributing meaningful data to some interesting projects, and is particularly productive in estuaries with bird families like waders and gulls. On Bardsey, we don't tend to get a huge number of colour-ringed birds coming through, so it has been great to obtain combinations of around 10 Kittiwakes from the big flocks that have been loitering around the coast. A quick search on the excellent 'cr-birding' website lead me to the scheme responsible for ringing the colour-ringed birds. You can work out who to email via a number of different details, such as which leg the metal ring is on, how many colour rings there are, whether any of the rings are coded (as in Darvic rings, which often have 3 or 4 letter codes), and also which colours are used.

One of the colour-ringed Kittiwakes
Spot the colour-ringed bird!

It turned out that all the colour-ringed Kittiwakes were from the same project, based in western France. I emailed the person carrying out the project, and was pleased to get a rapid response detailing all the facts relating to 'our' birds. I have included the shortened 'fact files' below for a few of the Kittiwakes, but basically all of the birds had come from France's largest black-legged Kittiwake breeding colony in Pointe du Raz (see map for details). As the ringing scheme has been operational for over 10 years now, with hundreds of birds ringed, one could assume that a fair proportion of the birds in our monster flock have originated from this colony. This is pretty interesting, as you would otherwise be tempted to think that the flock was simply formed of birds gathered from our own breeding colony, or perhaps colonies further up the Welsh coast. 

Bird 1 - Orange/Red/Metal-Orange/Orange/Orange (Paris FX21068) - seen on Bardsey on 13/08/16
Born in pointe du Raz (Plogoff, Brittany, France) in 2009. 
First resighted in the study area in 2011. 
First breeding attempt: 2013 in it's natal colony
Sexed as female. Bred 2014
Skipped breeding 2015, but bred in 2016 in it's natal colony (on another cliff) - failed at chick stage
Last seen in Brittany on 26/07/2016

Bird 2 - Red/White/Metal-Red/Black/Black (Paris FX23518) - seen on Bardsey on 13/08/16
Born in pointe du Raz in 2013
First resighted in the study area in 2015
Established in another colony in 2016 (pointe du Van, Cléden-Cap-Sizun, Brittany, France) but did not actually breed 
Probably a male
Last seen in pointe du Van on 09/07/2016

Bird 3 - Yellow/Blue/Metal - Lime/Black/Red (Paris FX17424) - seen on Bardsey on 15/08/16

Born in pointe du Raz in 2005
Resighted every year from 2008-2016 
Breeding attempts from 2010-2013 (in its natal cliff) and 2014-2016 (in pointe du Van colony)
Sexed as a male
Failed breeding in 2016 at chick stage (colony under heavy predation by peregrines)
Last observed 11/07/2016

Bird 4 - Red/White/Metal - Red/Green/White (Paris FX17424) - seen on Bardsey on 15/08/16
Born in pointe du Raz, 2013
Resighted in 2015 & 2016 in its natal colony only
Hasn't started breeding yet, probably female
2016 : observed on 10 occasions/days from mid-April, last observed on 27/07/2016 

Bird 5 -  Yellow/Red/Metal - Blue/Blue/White (Paris FX17424) - seen on Bardsey on 15/08/16
Born in Karreg Korn (Goulien, Brittany, France) in 2002
Resighted in every year from 2005 - 2016 
Breeding in its natal cliff from 2007-2009, but failed every year
Bred in pointe du Van colony from 2010-2016 and was successfull every year
Sexed as Male
Last observed on 29/07/2016

Bird 6 - Red/White/Metal - Blue/Black/White (Paris FX23601) - seen on Bardsey on 15/08/16
Born in pointe du Raz in 2013
Resighted in 2015 & 2016

2016: established in it's natal cliff, a few meters from it's natal nest, with a 13 year old female, but did not build a nest
Last observed on 04/07/2016

Looking at the details here, it is really interesting to see the time frame within which the birds have left their colonies and travelled up to Bardsey - many within a month, some within a couple of weeks (maximum). It would be interesting to find out whether the whole flock was comprised of birds from these french colonies, or whether there is a mix from several different populations. 

One of the flocks alighted on the island's southern tip

Kittiwake in active wing moult - another interesting feature of many of the birds in the flock. A lot of the birds have been carrying out their annual moult, renewing their worn primaries with fresh feathers. Growing new feathers takes a lot of energy demand, so perhaps these birds have been finding rich feeding around the island, which is facilitating their annual moult?
There are plenty of questions to ask!

Kittiwakes are such a charismatic coastal seabird, whose wailing calls epitomises the sea for me. Unfortunately, this species is experiencing worrying declines across much of its range, particularly in large northern colonies. Kittiwake numbers in Britain and Ireland have declined by 63% between 1986 and 2014, but in some northern colonies like Orkney and Shetland, declines have been as high as 87% since 2000. In the Irish Sea, this decrease has been somewhat less marked, with small increases in some colonies even. Here on Bardsey, the population has shown slight decreases in breeding numbers in the last few decades, but recent years have seen slight recoveries to our breeding population. Last year, for instance, saw a total of 125 nests on the East Side, which was a 20% increase on 2014, but a worrying 34.5% down on the 2006-2015 figure.

Reasons for these declines could be multi-fold and complex: fisheries have impacts on the availability of their main prey - sandeels -  and new evidence is suggesting that climate change and associated changes to sea surface temperature represents a real driver to the Kittiwake declines too: the changes to sea temperatures is causing declines and changes to plankton populations, which is the main food source for sandeels. Riding the change up the foodchain, and you have a domino effect. 

It's really sad to read the figures and hear about these declines - but monitoring populations, and contributing to studies such as colour-ringing projects like this one can help to understand more about the feeding behaviour and distributions of this species' populations both during and outside of breeding seasons. This can then inform governements and fisheries on where the most important areas are for this species, perhaps resulting Marine Protected Areas in some places to at least give the Kittiwake a hand whilst we tackle the bigger issue of our changing climate.

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