An evidence-based study mapping the decline in freshwater ponds in the Severn Vale catchment in the UK between 1900 and 2019

Abstract

Freshwater ponds have long been an overlooked biodiversity store and changing types of land use and the land management practices has led to a steady decline in pond numbers. Establishing the regional extent of pond loss is the first step in identifying key areas for conservation action. This study calculated pond loss in the Severn Vale catchment UK since 1900. Identification of pond location and surrounding land use on historic and contemporary maps enabled a comparison of total number, density and distance between present day and historic ponds. 57.7% of ponds present in 1900 were lost and pond density declined from 7.3 to 4.5 ponds km−2 between 1900 and 2019. This resulted in a 24.6 m increase in the average distance between contemporary ponds. Land use was an important factor in determining pond loss. Although in 2019 the highest density of ponds are in rural areas, 62.3% of ponds lost were from agricultural settings (arable or pasture). Our results highlight the significant pond loss experienced in the Severn Vale since 1900 and provide a valuable baseline for pondscape restoration. The methods described are widely applicable to other regions either with a history of ponds or an environment that could sustain them.