Following on from the news last week of the first Manx shearwater back in the nest box colony, the last few nights have seen ever increasing arrivals. We paid another visit to the colony today and 2 more pairs were back in the same boxes they left last September. In that time they have flown around 14,000 miles each to and from the east coast of Argentina. In a long running project with Oxford University and our own RSPB Conservation Science department we track the movements of birds in these nest boxes using devices called geolocators. These are tiny loggers that record changes in light levels which allow sunrise and sunset to be determined. This in turn allows an approximate location on the globe to be calculated - down to around 100km. So while not as accurate as GPS in terms of pinpointing, for example, where birds are feeding, they allow us to track them on migration and on their wintering grounds. While we can do a lot to protect them here in Wales on their breeding sites, they spend half the year in international waters. The more we know about their movements and patterns away from the safety of nature reserves the better armed we are for protecting them year round.
Geolocator leg mounted on a plastic ring on one of our Manx shearwaters. The device plus ring weighs less than 1% of an adult's bodyweight
Pair of Manx shearwaters in one of our artificial nest boxes. The hatch on top allows easy access causing minimal disturbance to the birds
Thanks Greg. Nice blogb