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| The migratory behaviour of two Lesser Black-backed Gull Larus fuscus subspecies, fuscus and
intermedius, was studied using satellite telemetry. To this end, first-year birds were equipped with
satellite transmitters and released either at their natal site, or after transferring to a breeding site
of the other subspecies. In addition, first-year birds from cross-breeding experiments between
the two subspecies (fuscus x intermedius) were also equipped with satellite transmitters. In total,
eleven first-year birds were successfully tracked during their initial autumn migration, at least one
from each study group. First-year birds from the Danish intermedius subspecies migrated either
southwest along the coast of the North Sea or through central Europe to Algeria. By contrast,
first-year birds from the Finnish fuscus subspecies migrated on a south-southeastern course
towards Ukraine and the Bosporus, Turkey. Only one of the transferred gulls could be tracked
long enough to accurately determine the migratory behaviour: this bird from the intermedius
subspecies left Finland on a south-southeasterly course towards the Ukraine, where transmission
ceased. Thus, this gull resembled the migratory behaviour of the fuscus subspecies. One bird
from the cross-breeding experiments wintered in Libya, but the migratory behaviour remained
unknown due to the lack of positional data. | |
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