Week Seven – Puffins

This week, Bill and the team are on the island of Craigleith, in the Firth of Forth, a mile offshore from North Berwick in Scotland. While puffin numbers on neighbouring islands have multiplied, the Craigleith population has crashed in the last five or so years.

Dusty and Sasha investigate. There are a number of obvious puffin predators in the skies above Craigleith, like gulls and peregrine falcons, but they are not in high enough numbers to have driven the puffins down so quickly by themselves.

Having made a rather precarious landing on the island, the team inspect the greenery close up. They notice something strange about the vegetation – the island has been invaded by tree mallow plants.

Tree mallow, which grows up to three metres tall, is blocking entrances to the burrows that the puffins use for breeding. The island is overrun with the plant and the puffins are being forced out into the open which is leaving them vulnerable to predation by gulls.

Tree mallow is a Mediterranean plant that has spread northwards as winters have got warmer. The only hope for the puffins on Craigleith is to clear the new invaders away. The trouble is that pulling the plants out by the roots could cause soil erosion which in itself will stop the puffins burrowing. So, the team determine to try cutting the plants down as a test run.

The possibility of storms and rough seas make landing on Craigleith a bit hairy and the island is soon to be visited by seals giving birth, so the team must work a miracle if they are to clear sufficient tree mallow before nature drives them off the island.

See the story in pictures in the gallery.