Kittiwake Research at Cape Wrath
Friday, November 28th 2014
While the ringing team were at Cape Wrath at the beginning of July they were joined by two members of staff from the RSPB, Stacey and Emily, who were using GPS data loggers to monitor the feeding behaviours of Kittiwakes along the coast of Scotland. This work was done as part of the RSPB’s Sea Bird Tracking and Research project.
Kittiwakes build their nests in colonies on cliff faces. Each year several are ringed - but catching them is no easy feat! Adults have to be carefully hooked and lifted off the nests making sure eggs and chicks are not disturbed. They quickly become wary of the catching methods and fly off if approached at anything other than a very sedentary pace.
Once the adults have been ringed a ladder is used to gain access to the nests to ring the chicks that have hatched. This is done as quickly as possible in order to minimise the time that adults are away from the nests.
This year as well as being ringed 8 birds had a small, lightweight GPS tracker attached to the feathers on their backs. These birds then had to be caught again some days later to remove the tags and download the data. Although the data produced is accurate and almost instant it is quite a difficult business having to catch the birds for a second time. Each bird was colour marked to aid recapture. The coloured marks wear off after only a few days and cause no harm to the bird. The tags were attached to the feathers by tape and if not removed, these will naturally fall off after only a few days. You can see one of the black trackers in the photograph below.
Access to the Kittiwake colonies can often be tide dependant so there were only a few opportunities to return to try and recover the GPS data loggers. Despite all of the factors against us, five of the eight birds were recaptured and the trackers recovered which was quite an achievement.
The tracks below show the journeys made by three of these birds from the colony on the east side of Faraid Head when foraging at sea for food; each colour represents a different day. The birds had their own distinctive foraging habits with some travelling up to 210 miles in one foray to obtain sufficient food to sustain their young. Others foraged much closer to the colony.
This bird travelled the smallest distance from the cliff, on the second day (pink) travelling only a few miles.
This bird made the longest foray (blue) with three journeys in one day totalling over 200 miles on each journey.
We found that the birds often followed a similar foraging pattern although visiting slightly different locations. The bird below conducted a late evening fishing trip then turned round at midnight and headed back to its nest in the dark!
It was very interesting and rewarding for the ringers to be part of the team helping to collect data for this important project. Stacey has since been in contact updating us on her travels; currently she is on Signy Island in the South Orkney Islands of Antarctica working on conservation projects with the British Antarctic Survey. She sent us this photograph earlier today of penguins in Signy Bay down below the Falkland Islands. The maps were kindly produced for us by the RSPB.