5 %
raised of £12,000 target
by 21 supporters
Tim Birkhead avatar
Tim Birkhead

The long-term study of guillemots on Skomer Island

Fundraising for University of Sheffield

5 %
raised of £12,000 target
by 21 supporters

University of Sheffield

We help fund students and staff to equip them in their quest for knowledge

Charity Registration No. - exempt charity


Please help us to secure the long-term study of Guillemots on Skomer Island

Watch our video online


I want to say an enormous thank you to everyone who has donated to my guillemot monitoring research on Skomer. I have been overwhelmed by both the financial generosity shown and all the messages of support I have received. Donations to my Just Giving pages in 2014 and 2015 totalled over £14,000 which meant the study could continue in 2015. Now I need your help to ensure this work can continue in future years.
Watch my 2015 video which gives you some background, and read on for some updates about our recent research.

In the 1930s there were around 100,000 pairs of guillemots on Skomer's cliffs. But by the 1970s, when my study began, this had fallen to just 2,000 pairs. Since then the numbers have increased and there are now 25,000 pairs. The population on Skomer is one of just a handful of UK guillemot populations that is doing reasonably well at present.

But there's no room for complacency. The massive 'seabird wreck' of February 2014, the result of persistent storms, killed at least 40,000 seabirds, many of which were guillemots and many of which were from Skomer. Our long-term study, in which we have monitored the survival and breeding success of Skomer's guillemots, puts us in a unique position to understand the consequences of this wreck. 

Ironically, the wreck coincided with the decision to terminate funding for the study. The guillemot study started in 1972 and for the last 20 years was funded by the Countryside Council for Wales (CCW). In 2013 CCW became part of Natural Resources Wales, and the funding for the guillemot study stopped.

Read more about the study here: 

Nature magazine article - http://www.nature.com/news/stormy-outlook-for-long-term-ecology-studies-1.16185

Guardian article - http://www.theguardian.com/science/animal-magic/2014/oct/27/guillemots-skomer-climate-change-conservation

As the quality of our seas continue to decline as a result of climate change and over-fishing, it seems crazy to terminate a study that could help preserve one of our most important seabird species. This project needs £12,000 a year to continue. With your help we can carry on collecting the information that is so essential for understanding the health of this sea bird population, the state of the marine environment, and for recognising the effects of climate change and oil pollution on the ecosystem.

September 2016 update

Having raised £14,000 via Just Giving in 2014, in 2015 we were able to monitor the number of guillemots that survived over 2014-2015 winter, and make a detailed assessment of the consequences of the ‘Wreck’ caused by the severe storms in January and February 2014. Normally, we expect around 95% of breeding guillemots to survive from one year to the next (a 95% survival rate is equivalent to a breeding life span of around 20 years). However, the 2014 data indicated a substantially lower survival rate.

2016 has been a fairly ‘normal’ year for Skomer’s guillemots, although, to be honest, I’m no longer sure what ‘normal’ means. Here, however, it means that breeding occurred at a normal time and breeding success was good with around 80% of pairs successfully rearing a chick to fledging. We also looked at the size of guillemot eggs, and compared this with information we had collected in the last two years. As we had suspected, in 2014 the extensive storms resulted in guillemots producing relatively small eggs. My previous studies have shown that eggs tend to be small when food is scarce or the birds in poor condition – both of which were probably true in 2014. It is reassuring that 2016 seems to have be fairly normal.

We made an intensive study of chick-feeding rates, as well as the more usual diet study, because the last two years had suggested that there had been a decline in the rate at which chicks were fed as well as a change in diet. However, we found no evidence of any reduction in chick-feeding rates, which was a relief. The survival of guillemots between 2015 and 2016 appeared to be normal, which is good news after the major mortality caused by the 2014 storms. We estimate survival rates from the re-sightings of birds we have ringed, and each year we ring a new cohort of around 300 chicks and a smaller number of adult guillemots, to replace those that have died. 

Thank you for supporting this very special long-term study of guillemots on Skomer Island.  

If you have any questions about the study please e-mail t.r.birkhead@sheffield.ac.uk

Donating through Just Giving is simple, fast and totally secure. Your details are safe with Just Giving – they’ll never sell them on or send unwanted emails. Once you donate, they’ll send your money directly to the University. So it’s the most efficient way to donate – saving time and cutting costs for the University.


  • Tim Birkhead with guillemot chicks
  • a young chick too young for ringing
  • some of our colour-ringed guillemots +4