The British Trust for Ornithology’s (BTO) Heronries Census is one of the longest running bird surveys in the world but there are knowledge gaps for Grey Herons on some of the Scottish Islands and BTO needs help to fill them.
The Grey Heron is amongst Britain’s largest birds and can be seen in a variety of different habitats that include rivers and parks in some of our busiest towns and cities. Grey Herons usually nest in colonies in trees, building large nests very close to the tree tops where they are not difficult to see but getting information on them can sometimes be more tricky.

On the Scottish islands where woodland cover is sometimes sparse, Grey Herons can also be found nesting more frequently elsewhere, including on the ground. For this reason it can be more difficult to find and monitor heronries, and it is this information that BTO is interested in; where in the Inner and Outer Hebrides do Grey Herons nest?

Ian Woodward, Heronries Census Organiser at BTO, said ”We would love to fill in the gaps in our knowledge of heronries in these islands but to do so we need the help of those people that live there and those that visit during the early spring. In southern Britain Grey Herons begin breeding as early as February or early March but further north nesting tends to start slightly later and Grey Herons on the Hebrides may still be breeding well into May.”

The Census simply requires a count of the number of ‘apparently occupied nests’ at a heronry and the BTO would welcome all records of nesting Grey Herons from the Hebrides and other more isolated areas in Scotland. Additionally, we would welcome contributions from residents and visitors who would be willing to check previously known colonies to confirm whether or not Grey Herons are still nesting there.