13 Jul 2015

Tirrick, tirrick

Tirrick is the Shetland name for Arctic tern. These amazing little birds undertake one of the longest migrations of the avian world. They fly here to breed and then spending the winters in the southern hemisphere racking up tens of thousands of air miles per year. They're feisty little things and prone to attack you if you get to close to their colony.

I was lucky enough to be asked along recently to ring some Arctic Tern chicks on the Skerries off the Anglesey coast where a study is being involving colour flagging adults and ringing chicks. Only one visit to ring the chicks is allowed each year to avoid disturbance to the colony and the team comprises three ringers who have to ring 500 chicks in the shortest possible time. Already the scheme has thrown up some interesting  results!

Consequently  I found myself meeting Steve Dodd at 08.15 and transferring to his pickup for the journey to Holyhead marina and a rendezvous with the supply boat that takes stores and relief wardens across for the RSPB.

The  forty minute  boat journey  across was uneventful although the previous days winds resulted in quite a sea swell. As we approached the islands we started seeing more birds with auks, terns and the occasional gannet and Manx Shearwater. Nothing really prepares you for the sites and sounds of a full blown active tern colony and the noise was deafening.

Making our way up to the lighthouse we were constantly harangued by angry terns and had to be careful where we walked as there were young chicks and nests with eggs everywhere.

Once we arrived we were briefed on the days plan and set off with the wardens to round up tern chicks in different parts of the colony. We worked different parts of the colony and collected the chicks in plastic boxes so they could be released back into the colony in the area from which we'd collected them. The whole time we were subjected to the noise and aerial bombardment of  3000 pairs of angry terns.

Once we'd ringed our sample of 500 terns chicks it was time to beat a retreat to the lighthouse and enjoy a well earned brew and a piece of sponge cake kindly made and provided for us by Georgina. Awesome!
Whilst we had our lunch  I took the opportunity to get some photo's of some colour flagged adults. In the last two years 100 adults have been marked with individually lettered flags so they can be monitored in subsequent years. Questions such as do they use the same nest site and do they remain faithful to the same mate could be answered.

As well as 3000 pairs of Arctic Terns there are 1000 pairs of Common Terns breeding on the Skerries although the two colonies stick to defined areas. There are two Roseate terns in the Common Tern colony that have bred with Common Terns and we were lucky enough to see one of these birds.

No comments :