Rooks nest early in the year and you may have noticed them preparing for the nesting season by rebuilding or starting new rookeries. We are again requesting the submission of Rook nest counts in Hertfordshire for 2025.
In 2024, 197 Rookeries with 3215 nests were found. These numbers are down from the 209 Rookeries with 4628 nests found in 2023, however, this may not indicate a decline as survey coverage was not consistent. Rooks have been surveyed for a long period in Hertfordshire going back to a complete survey in 1960/61 where 521 Rookeries with 15739 nests were found (Sage & Nau, 1963). Numbers declined until the 1990's, but appear to be stable since, with a loss of Rookeries in the south of the county and trend towards more smaller Rookeries (Knight, Herts Bird Report 2021).
There are two ways to submit rookery counts. Records for existing rookeries can be added to the live google sheet here, where you can see the counts for other rookeries in 2025. Alternatively please submit your records to the Herts Bird Club website here including a nest count and six-figure grid reference. Mobile applications such as ‘OS Maps’ can be useful for calculating your grid reference in the field. A count of the nests that are active is not necessary, just the number of complete nests, provided the rookery as a whole is active. For inspiration of where rookeries might be, see the 2021 interactive map (locations are approximate).
For any questions about the Rookery survey, please contact Graham Knight here
