Extreme uncertainty and unquantifiable bias do not inform population sizes

BTO staff co-author a rebuttal letter setting out the importance of the careful use and interpretation of citizen science data in estimating avian population sizes.

Nesting dates of Moorland Birds in the English, Welsh and Scottish Uplands

Rotational burning of vegetation is a common form of land management in UK upland habitats, and is restricted to the colder half of the year, with the time period during which burning may be carried out in upland areas varying between countries. In England and Scotland, this period runs from the 1st October to 15th April, but in the latter jurisdiction, permission can be granted to extend the burning season to 30th April. In Wales, this period runs from 1st October to 31st March.This report sets out timing of breeding information for upland birds in England, Scotland and Wales, to assess whether rotational burning poses a threat to populations of these species, and the extent to which any such threat varies in space and time.

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Impacts of COVID-19 restrictions on capacity to monitor bird populations: a case study using the UK Breeding Bird Survey

Like many things, long-term monitoring of bird populations was interrupted during the COVID-19 lockdowns. Here, BTO scientists look at the effects of restrictions on participation in the Breeding Bird Survey during 2020 compared to previous years, and devise analytical methods to overcome the issues that emerged.

Bailiwick Bat Survey: 2021 Report

This report presents the main findings from survey work delivered using passive acoustic monitoring devices deployed across the Bailiwick of Guernsey in 2021, the first season of the Bailiwick Bat Survey, including the first extensive baseline data for bats for the islands of Guernsey, Alderney, Herm and Sark. 

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