In November we caught up with 3 satellite-tagged young sea eagles from previous years nests in East Scotland. In this blog we will look at the progress made by the 4 latest additions to the East Scotland sea eagle population that hatched in 2017. These young birds came from 3 successful sea eagle nests, one in Fife, one in Angus and one in Speyside.
A fascinating story developed at the Fife and Angus nests which we detailed in a previous blog post. This means that two of the chicks, 17BlueV (year – wing tag colour – wing tag letter) in Angus and 17BlueX in Fife, are probably half siblings. We judge the sex of these birds by taking weight and measurements known as biometrics during ringing and both are almost certainly female. In sea eagles the females are usually larger and Blue X is a perfect example as she's already much bigger than her father Turquoise Z.
The latest Fife chick Blue X in flight. Image credit Dennis Gentles
Sea eagles usually disperse in September or October, typically venturing far from their natal nest, however in this case neither of the two sisters has ventured far. Blue V has been on a brief excursion west into Perthshire and north into Deeside, reaching a distance of 57km from the nest before heading back. Blue X on the other hand has determinedly stayed put, venturing out only to follow her mother, Turquoise 1, to a favoured fishing spot on the Eden Estuary.
The Fife sea eagle family. Turquoise Z (left), Turquoise 1 (right) and their latest offspring Blue X (centre). Image credit Richard Tough
Meanwhile in Speyside twin males 17BlueT and 17BlueO dispersed from their nest in early September, following the typical pattern of behaviour for young sea eagles. They first head north, with Blue T reaching Lossiemouth on the north coast of Moray before heading back to the nest. After a brief rest they then made a more determined move, heading south, this time into Deeside and the Angus Glens where they have been ever since.
GPS track of Blue T (purple) and Blue O (pink) between September and November 2017
The image above shows their dispersal into Deeside but it doesn’t tell the whole story. Although they’ve roosted, scavenged and hunted in many of the same places they are very rarely in the same place at the same time, for the most part staying decidedly separate. Both however have spent time with other sea eagles, particularly 16WhiteL and 16White Diamond – their older sister!
It's great that they are spreading out. It takes time but they will surely merge with other eagles until the whole of Scotland has resident seas eagles.