Fascinating Talk given by Mick Brown

Posted by Tenby Museum on Aug 20, 2018 Blog No Comments

As part of Tenby Museum and Art Gallery’s commitment to present high quality events for all, local naturalist and seabird specialist Mick Brown gave a fascinating insight into the life of the gannet at the museum last Friday (17 August).

Mick related that there had been little published material on seabirds until Ronald Lockley’s 1954 book. Lockley – so devoted to seabirds that he spent the first night of his honeymoon on Grassholm – later went on to establish the Field Study Centre at Orielton. Grassholm is the third largest gannetry in the world, with more than 29,000 birds colonising the island. Specialist members of the British Trust for Ornithology now ring the birds and put GPS trackers on them to research their movements.

The gannet is a true sea bird. Unlike gulls, which nest and feed inland, the gannet only comes ashore on remote islands or promontories to nest and spend most of October, November and December at sea. The birds pair for life and each year rebuild their nests, some of which are 2metres high. They maintain a whole series of rituals and displays to maintain their close bond. The birds have binocular vision, nearly a 2 metre wingspan and can fly up to 40 mph. Their breeding rate is successful – 84% of their eggs hatch and 90% of the chicks will fledge.

The birds are at their most spectacular to watch when they are feeding. Once a fish is spotted they dive down and twist their wings into their bodies as they hit the water at about 75 mph; they catch and swallow the fish under water, to avoid predation by other sea birds. Scientists, using GPS trackers, have traced birds flying as far as 200 miles to feed and catch fish, to return and regurgitate to feed their chicks.

The biggest enemy the gannet faces is, probably unsurprisingly, Man. Plastic has appeared in the digestive systems of dead gannets and also litters their nesting colonies. Blue is particularly attractive to them and much of the rope used on sailing boats and trawlers is blue polypropylene. Fishing hooks also become embedded in their feathers and flesh and fishing line and nets wrap around their feet, trapping the birds in land or water.

The audience was extremely appreciative of Mick’s knowledge and relaxed delivery and it is hoped that we can persuade him to give an additional talk at the museum in the not too distant future.