Bergmann’s rule (or ‘law’) is one of the oldest in ecology and evolutionary biology, first presented in 1847. This rule states that animals inhabiting colder climates/latitudes are larger, with greater volume than individuals of the same species occupying warmer climates/latitudes.

This study assessed the use of glue-mounted GPS tags to track Goosanders in two Scottish river catchments with contrasting management regimes – the Tweed, where licensed shooting occurs, and the Forth, where it does not.

This report was commissioned by the Northern Ireland Environment Agency to scope the evidence available on the movements and spatial distributions of certain marine birds in and around Northern Ireland waters, in order to identify knowledge gaps. The focus is on 37 marine birds found offshore, away from the coastline, that utilise the Celtic Seas (OSPAR Region III) and Ireland Exclusive Economic Zone marine environments. Metadata from 10 different sources (including directly contacting researchers, a literature review and accessing several archived datasets) are used.

GPS tracking of three large gull species from the Isle of May, Scotland, revealed overlap in foraging habitats used during the breeding season, but differences in the where the three species foraged, and the strength of their preference for particular habitats, especially landfills, urban and coastal habitats.

This report investigates the efficacy of methods for producing population trends from BTO/JNCC/RSPB Breeding Bird Survey data for six breeding wader species in the UK. It examines the effects of increasing the count threshold on the population trends for these six species, and also explores the effects of different geographic exclusion rules on the population trend of Golden Plover. Overall, it aims to test for any potential biases in the current trends, and in doing so, determines whether we can create a better approach which provides the most robust data for wader conservation moving forwards.

This report reviews the suitability of methods used to calculate the scale of Artificial Nest Structures (ANS) provided as compensation measures for Kittiwake mortality at offshore wind farms in English waters, due to turbine collision only. This report was revised in October 2025 and republished on 30-10-2025, correcting an error in Table 5. The recalculated compensation populations in the original report did not match the underlying fecundity values in the column headers. In addition, a link to helpful computer code was added to Appendix 3 (see below).

This study used DNA metabarcoding on faeces collected opportunistically during the breeding season, to identify fish and marine invertebrate prey in the diet of Shag and Kittiwake in western Scotland. Read our BTO blog on making this research accessible through the medium of a comic!