The news that a pair of ospreys had become established on lagoon four was fantastic, particularly when we learned that they were incubating! This meant that we could potentially have eight successful nests this year, and two pairs of ospreys on the nature reserve. However, it hasn’t played out as we’d hoped. Unfortunately, the nest on lagoon four has now failed due to aggressive and determined intrusions by more than one pair of Egyptian geese. 3J laid her egg last Thursday, and both she and 51 had been incubating it for twenty-four hours. The next day, the geese attacked the nest.
Egyptian geese are not native, they originate from Africa. Their native range covers most of Africa south of the Sahara and the Nile Valley. They were introduced to the UK in the 18th century as an ornamental bird, and escapees spread into the wild. They like to nest in trees, whether in osprey nests, tree holes, kestrel boxes, barn owl boxes or any other hole they can squeeze into. This causes problems for native birds who also nest in holes or trees, as it means a shortage of suitable nest sites. This is particularly damaging for species such as barn owls, who are suffering in this country and need all the help they can get. Due to their displacement of native species, Egyptian geese were officially declared a pest in the UK in 2009.
Whilst some people like these geese and welcome them (click here), they have caused problems here and elsewhere for many years, and could potentially cause even more problems in future as their numbers continue to rise.
Egyptian geese have the ability to breed throughout the winter months, therefore can establish themselves in places such as osprey nests before the rightful owners of the nest return to stake their claim. This occurred in Manton Bay in 2015, when a pair of geese took over the osprey nest and laid an egg in it. Conveniently, a crow ate this egg, and 33 and Maya were strong enough and experienced enough to chase off the geese.
51 and 3J’s lack of experience will have contributed to their inability to defend their nest effectively. The aggravated attack by the geese led to the failure of this new nest, and the breakdown of the ospreys’ partnership. The pair have since abandoned the nest, and 51 has been seen sitting on another platform, alone.
This wonderful sequence of photographs and an incredible video by John Wright demonstrate the extent of the problem the geese caused the ospreys, and the ospreys’ vain attempts to see them off.