The Work of the Bird Observatory - Obbyr yn Thie-arrey Eeanlee

The Bird Observatory on the Calf was established in 1959 and became an official British Bird Observatory in 1962. From March to November each year wardens live on the Calf, keeping detailed records of migration and of the breeding birds which visit the Island. To record the birds, the wardens must first catch them.

The Heligoland trap is a large tunnel of fine wire mesh with a catching box at one end. The "driver" lightly tapping the nearby vegetation drives the birds into the trap, calling and arm waving. The door flap on the collecting box is closed when the last bird enters, allowing each bird to be carefully removed and placed in soft bags for transporting back to the Observatory. There the wardens record details about the birds, such as species, weight, age, sex and condition. Those which are not already ringed, have a ring placed on their leg. Then they are all released again.

A mist net is a very fine net suspended between two poles. Birds, and other wildlife such as bats, fly into the net which is virtually invisible. The nets are patrolled regularly and the birds are carefully removed when caught and taken to the Observatory for recording.

The ringing of the birds is one of the main duties of the wardens of the Calf Observatory. Ringing involves placing a light metal ring on one of the bird’s legs for recording and identification purposes and is painless to the bird. Ringing helps to monitor migratory routes and destinations, lifespan, causes of death, changes in population numbers and breeding success. The rings feature an identity number for each bird and are applied to the bird’s leg using special pliers ensuring that the ring closes perfectly to the required size.

By the end of the year 2001 99,042 birds of 134 species had been ringed since the Observatory opened of which 11,280 have been traced along their migration routes by other bird observatories.

Please see the Visitor Information page for details of opening hours.

For information about The Bird Observatories Council, please visit www.birdobscouncil.org.uk.