Perch (Perca fluviatilis) abundance, sex, age, length and weight from Windermere North and South Basins, UK, 1943-2019

Perch traps were used to catch perch (Perca fluviatilis L.) in Windermere from 1943 to 2019 at different locations throughout the North and South Basin of Windermere. Here, data from four sites are given: Green Tuft, Rawlinsons Nab, Lakeside and Chicken Rock. Perch trapped at these sites were weighed (mostly individually, but sometimes in bulk in the early years), sexed, measured and ages were determined on all individuals or a subsample. The Windermere perch population experienced a major disease (pathogen) outbreak in 1976, which induced a massive mortality, mostly among large mature individuals. The data were initially collected by the Freshwater Biological Association (FBA) but have been collected by UKCEH and its predecessor Institute of Freshwater Ecology and CEH since 1989. Perch trapping has stopped in December 2018. All sampling was undertaken and data originally collected using standard, published methods that complied to all ethical standards of the time and capture methods were not changed over time to ensure consistency. All data was obtained from animals taken from the wild to obtain measurements for scientific purposes by experienced individuals following standard procedures at the time.