Seabird Counts 2023 - How Did We Count Them?

 If you were on the island in May or June, you may have noticed our staff carrying out lots of land and boat surveys – that’s because it was seabird counting season. With the aid of some photos, we thought it would be nice to explain a little more about what the survey work entailed. Our Puffin counts were completed in March (see blog post here) so we were focusing on Guillemots, Razorbills, Fulmars, Kittiwakes and Manx Shearwaters.

Rob and Leighton fixing up the boat ready for launch

Rob on his powerboat course pre-season

Guillemots and Razorbills

Our counts for Guillemots and Razorbills started on 25^th May and had to be completed by 11^th June. The island is split into 45 sections of coast, each of which has to be counted twice. Every Guillemot and Razorbill in suitable breeding habitat (not sitting on the tideline and clearly on nest sites) are counted.

Hannah and Lisa counting Guillemots and Razorbills

The photo below shows the difference between a Guillemot and a Razorbill. Razorbills are black with a blunt thick bill with a white stripe and a long pointed tail, whereas the Guillemots are chocolate brown with a shorter tail and long thin beak.

A Guillemot (bottom) and pair of Razorbills with a chick (centre)

Fulmars and Kittiwakes

The counts for these birds start on the 1^st June to time with their incubation, though the rest of the methodology is the same.

Kittiwakes are found in dense colonies. They are medium-sized gulls with black legs and wingtips, a prominent dark eye and yellow bill. Fulmars, who are members of the Albatross family despite resembling gulls, have broad stiff wings and a prominent “tube-nose” capable of spraying an oily substance at predators when threatened.

Kittiwakes on a cliff face with chicks

Hebe and Issy counting Fulmars and Kittiwakes from the boat

Manx Shearwater Census

To monitor the Manx Shearwater numbers, we have a series of 100m² circular plots around the island. As this starts on 1^st June, Manx Shearwaters should be on their nests incubating during the day. As a team, we move through the plots, playing Manx Shearwater calls down every burrow we find – the Manxies will usually call back to the recording if they’re in there. By working out how many burrows in a plot are occupied, we can scale this up to get an estimate of island numbers.

Rob, Hebe, Erin and Lotti putting ropes to mark the Manx Shearwater area

Leighton and Erin checking burrows

Will playing a Manx Shearwater call down a burrow

From all of this data, we can calculate the populations of these five seabird species on Skomer. It tells us how our seabirds are doing and informs our conservation management for the future.

We are incredibly grateful to all our staff, researchers and weekly volunteers for their help in completing this work. We are especially thankful to Hebe, our seabird volunteer, Erin and Lotti, our long-term volunteers and Issy, our 2022 seabird volunteer, for their tireless work on boat and land surveys. 

Hebe on our boat

The team celebrating the completion of another Manx Shearwater plot - this one took 5 hours!

Until next year, seabird counts!

This project is funded by the Nature Networks Programme. It is being delivered by the Heritage Fund, on behalf of the Welsh Government. We are very grateful, as this funded the boat repairs, boat clothes, Rob’s powerboat course and whole island seabird counts.

Rob modelling some of the new boat clothes provided by the funding.