In today’s blog, RSPB volunteer Ali Barratt describes the results from a ground-breaking citizen science project published today in which used photographs to study Puffin diet around the UK.
full paper can be found here
Atlantic puffins are endangered in Europe, and numbers have been declining for decades1. Changes in prey availability through climate change, unsustainable fishing and other human activities has been linked with poor breeding success in many parts of their range. Understanding the impacts on UK puffins—10% of the global population—is vital to save them.
As puffins return to UK waters to breed each spring, they spruce up burrows as nurseries for chicks, affectionately known as pufflings. Only two of the UK’s large puffin colonies routinely monitor the diet fed to chicks as traditional methods are very labour intensive, and replicating these UK wide would be prohibitively expensive. So, the RSPB undertook a bold new initiative: to attempt to simultaneously survey diet in as many puffin colonies as possible in the UK and Ireland in one breeding season.
How? By inviting the “Puffarazzi”! Put simply, we asked the public to submit photos of puffins carrying prey taken between May and August, when puffins very visibly bring their catch back to the colony to feed their chicks. And the first results are now out!
The response to this novel citizen science experiment was astonishing, with 1,402 photos submitted. Photograph quality was excellent, with 89% of birds in images providing useable diet information. Our team of ‘Puffineers’ then identified over 11,000 items, which were also measured to estimate the total weight of each delivery to chicks in 27 UK colonies.
Puffineers being trained in identification and measurement of fish
What did we learn?
Not all puffin burrows are created equal.
Prey availability and ocean conditions around the colony affect what the adults can catch for their chicks, and the type of prey and its quality, that is, its size and weight, affect chick health and survival.
In Shetland, where puffin populations are facing declines, the photos showed that puffin parents carried more prey items per trip than in any other region—often smaller, younger fish, making a less nutritious meal. In contrast, in Wales, where puffins are currently faring better we found each delivery contained fewer prey items, but these fish were more substantial, meaning more reward for less effort.
Sandeels dominate but are not the only important prey item
Sandeels are slender silver fish featured in “classic” puffin photos and were indeed present in most Puffarazzi images.
The photos showed the importance of sandeels throughout the season, brought as juveniles for young chicks and in their adult form for growing pufflings. While sandeels were the only prey item recorded in some colonies however, they amounted to just a third of the chicks’ diet in others. Other prey species, not previously as well studied, have also been highlighted by this novel diet study. Species such as herring, rockling, and sprat appear to be crucial alternative sources to sandeels in some puffin colonies during chick-rearing.
Puffing carrying Sandeels - Ali Barratt Puffin carrying Gadoids - Oliver Prince
Linking Puffin diet to conservation status
The team found that the size, type and number of prey brought back by Puffins for their chicks varied between colonies in different regions. Severe declines in Puffin numbers were associated with colonies where Puffins were only finding smaller fish such as young sandeels and rockling to feed to their chicks, whereas Puffins at colonies which are currently doing better tended to bring back larger fish such as mature sandeels.
Shetland’s coastal waters are now lacking once plentiful sandeels and sprats. RSPB tracking tags have shown that these puffins must often fly further to find food, costing more energy to do so (RSPB, unpublished data). Puffarazzi photos additionally revealed that over 80% of Shetland chicks’ diet was made up of transparent sandeels. At Fair Isle, whiting and saithe made up to one-quarter of the diet, yet were seldom photographed in other colonies. Puffin numbers have declined by more than 50% in Shetland over the last two decades, and the Puffarazzi data suggests this may be linked to prey availability, though further work would be needed to confirm this.
What are the broader implications for puffin conservation?
We have shown that crowd-sourced photos are a viable and cost-effective way to collect puffin chick diet data UK-wide in one breeding season. By replicating these efforts in future, we can better understand changes in prey available to Puffins across the UK and Ireland, and the implications for breeding success.
Such data can help to inform conservation management, and can provide a window into the health of the UK’s waters.
Mosaic of images submitted by the 'Puffarazzi'
Acknowledgements
Huge thanks to everyone who contributed photos as part of the Puffarazzi, as well as to all the Puffineers that have been involved in Project Puffin UK: Sian Haddon, Georgia Longmoor, Oliver Prince, Sophie Elliott, Chris Cachia-Zammit, Fritha West, Frith Dunkley, Katie Ford, Katie Horton, Alison Barratt, Alice Edney, Vicky Sewell, Antaia Christou, Eliska Kosova, Rob Hughes, Alexandra Fink, Hannah Snead, Jack Barton, Jodie Henderson, Joseph Whitney, Kate Westerberg, Sabiya Sheikh, Tessa Broholm, William Bevan.
This work was supported by the National Lottery through the Heritage Lottery Fund.