Migration May

The Isle of May is a National Nature Reserve, owned and managed by Scottish Natural Heritage. David Steel, Reserve Manager on the Island, gives us his insights into the incredible variety of migrating birds that visit each year.

The Isle of May National Nature Reserve is famed for its seabirds and important Grey Seal colonies as well as its history dating back to the seventh Century. It is home to thousands of nesting Puffins (the largest east coast population with over 40,000 pairs) and over 2,500 Grey Seal pups are born annually between September-December. However one aspect of the island which is not as well talked about is its appeal to migrating birds.

Known as the ‘Jewel in the Crown’ the Isle of May is situated at the mouth of the Firth of Forth between the coasts of Lothian and Fife. At 57 hectares and just under one mile long, it is the largest of all the islands in the Forth. During the spring and autumn migration periods, thousands of birds will use the island like a service station; stopping over to re-fuel (on seed and insects), rest and take relative safety from the rigours of travel.

As well as resting, birds use the island as a way-marker to cross the Firth of Forth whilst any flying in from the east will be greeted by the island before any other landfall. This unique position makes the Isle of May one of the most important migration stations on the east coast with thousands of birds using the island annually. In the spring, birds which have overwintered in southern Europe and beyond travel back to breeding grounds in Scotland and further afield. When they pitch down on the island the majority are in fine summer plumage, but the urge to keep on migrating north to their breeding grounds to claim the best territories usually means they do not stick around the island very long.

However, that all changes in the autumn as birds take on a more relaxed approach on their return journey. Migration between August- October is very different and usually involves a lot more individuals. Young inexperienced birds undertaking the journey for the first time migrate through the island and often linger for several days, whilst adults are in no hurry as they feed up putting on valuable fat layers before undertaking non-stop flights to southern Europe. There are other key factors to birds arriving and leaving the Isle of May as weather dictates numbers (easterly winds will bring more birds) whilst timing is crucial. Certain birds like warblers and chats will migrate early whilst crests and thrushes will move later.

Goldcrest

David Steel

It’s also not all about birds heading to Europe. In late autumn birds escaping the harsh weather of Scandinavia will head to the UK to winter and use the Isle of May as a gateway into the country. If the weather conditions are right, thousands of thrushes can be counted over the island with redwings, fieldfares, song thrushes and blackbirds all moving. Add in birds such as woodcocks from Russia, geese from Iceland and owls from Scandinavia, the Isle of May can certainly feel like the M1 on the migration route.

As staff living on the island throughout these exciting times, we work alongside volunteers at the Isle of May Bird Observatory (Scotland’s oldest Bird Observatory) to monitor, record and ring thousands of birds each year. Detailed studies have shown that in recent years blackbirds from Norway, goldcrest from Finland and bramblings from Belgium have all been caught as they pass through on their journeys. With over 280 different bird species recorded, the Isle of May is certainly in a class of its own. So the next time you look out to the island, just think how important it is for wildlife, whether it’s seabirds, seals or all those migrants winging their way over the Jewel of the Forth.