Approximately half the world’s population of Manx shearwaters nest on Skomer and its “sister” island of Skokholm with an estimated total of 310,000 pairs on Skomer itself and 40,000 pairs on Skokholm, making this the world’s most important breeding site for the species. The birds usually nest in rabbit burrows. The two islands are also home to the largest colony of puffins in southern Britain (10,000 breeding pairs), many likewise nesting in the burrows created by the large population of rabbits.
BBC Radio 4’s Living World visits Skomer Island off the south east coast of Wales and home to thousands of seabirds.
There are 25,000 guillemots packed together on the cliffs, no other bird breeds in such close proximity to its neighbours. Fights and squabbles constantly break out, but friendships and pair-bonding are very strong. They keep the same mate for life and produce one chick a year. The fledgling has to leap from the sheer cliff face into the sea below to find its dad, surrounded by thousands of others, and try to avoid being eaten by predatory gulls. Each year each guillemot pair comes back to exactly the same place on the cliff ledge and they defend it vigorously.
In the early decades of the 20th Century there were 100,000 guillemots on Skomer but numbers plummeted to just 2000 after the second world war, probably due to oil pollution in the sea. Now numbers are slowly recovering but the increase in storms may be a problem for them in the future. Listen