ROSKILDE FJORD

Hyldeholm in Lejre Vig

Nets off the north coast of Hyldeholm.

Up until and during the 1970s the island of Hyldeholm had a very rich bird life. It was dominated by the colony of black-headed gulls (about 1500 pairs) but was also home to most of the other species breeding on the fjord.

Black-headed gulls over their colony on Hyldeholm.

While it was still permitted to gather gulls' eggs thousands of black-headed gulls’ eggs were collected every year on Hyldeholm. Egg gathering stopped on May 25th and the birds usually managed to raise a late brood.

The birds did not abandon the island as a breeding site because of the egg gathering, but because Hyldeholm is one of the islands worst affected by rats. In the spring of 1999 the Ministry of the Environment’s consultant estimated the rat population on Hyldeholm at about 200, but such an estimate is naturally very approximate. Because of the rats the number of breeding birds has been very small in recent years. In 2000 the rats were all finally destroyed but we know from experience that it normally takes quite a few years for breeding birds to return after the cause of the disruption is removed.

The vegetation is mostly tall grass, but there are also large beds of common mallow.

Mallow on Hyldeholm.