BTO appeals for information on Scottish heronries

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.

Grey Heron is among Britain's largest birds and can be seen in a variety of different habitats, including in some of our busiest towns and cities. The species usually nests in colonies in trees, building large nests very close to the treetops. Despite these colonies being relatively easy to see, getting information on them can sometimes be tricky.

Grey Heron breeds widely across Britain, but its nesting habitat choices in north-west Scotland are poorly known (John Kinsey).

In the Scottish islands, where woodland cover is sometimes sparse, Grey Herons can also be found nesting more frequently in other situations, 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 in 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 welcomes all records of nesting Grey Herons from the Hebrides, as well as other remote areas of Scotland. The organisation also welcomes 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.

For more information and how to take part, please visit the Heronries Census on the BTO website.