Tuesday 19th January comments: Over the last few days we’ve continued our series of looking at the breeding seabirds of the Isle of May NNR. Our recent focus has been on the European Shag as we looked at the breeding biology, identification and the trends in their populations over the last thirty years. Today we are asking for your help in tracking these birds down if you find them dead or alive.
Research on the Isle of May is hugely important and our friends at UKCEH have been studying the islands Shag population for a considerable amount of time. During this period a colour ringing scheme between the University of Aberdeen and UKCEH has been looking at the dispersal of the breeding Shags from the Isle of May and other east coast breeding sites. During the summer breeding adults and chicks are fitted with a unique colour ring with three digits; which makes it easy to read at distance with binoculars or telescopes.
What we now need is those sightings! Anyone can take part, so if you are out and about along the coast (especially the east coast) with a pair binoculars, telescope or camera, check out the roosting Shags and spot the coloured rings. If you find any or discover them as tideline corpses over the winter please report all sightings to: shags@ceh.ac.uk
It’s all part of the science and you’ll be making a valuable contribution to increasing our knowledge of this very special seabird. Now go find some colour rings…
As a follow up, Dr Francis Daunt shared a recent paper which was written regarding the ringing scheme on the Isle of May – you can find it here: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0098562
As a snap-shot the findings revealed that field resightings of colour-ringed adult European shags known to have bred on the Isle of May were followed to quantify individual variation and repeatability in winter location within and among three consecutive winters. In total, 3,797 resightings of 882 individuals were recorded over 622 km of coastline. The distances from the Isle of May at which individuals were resighted during winter varied substantially, up to 486 km and 136 km north and south respectively.
Repeatability did not differ significantly between males and females or among different age classes, either within or among winters. This data demonstrates that the focal shag population is partially migratory and moreover that individuals show highly repeatable variation in winter location and hence migration strategy across consecutive winters. Such high among-individual variation and within-individual repeatability, both within and among winters, could lead to substantial life history variation, and therefore influence population dynamics and future conservation management strategies (Grist H, Daunt F, Wanless S, Nelson EJ, Harris MP, et al. (2014) Site Fidelity and Individual Variation in Winter Location in Partially Migratory European Shags).
Isle of May National Nature Reserve 