Digital video aerial surveys of marine birds and mammals at Solway Firth SPA: February 2021.
Abstract
NatureScot and Natural England commissioned HiDef Aerial Surveying Limited (HiDef) to undertake a high-resolution digital video aerial survey for marine megafauna, ornithological and human activity within the Solway Firth SPA, which extends between the coasts of Dumfries and Galloway, southwest Scotland and Cumbria, northwest England. In February 2021 and January-February 2022, surveys were undertaken using an aircraft equipped with four HiDef Gen II cameras with sensors set to a resolution of 2 cm Ground Sample Distance (GSD). The digital aerial surveys recorded a total of 28,928 birds of 38 species and 41 non-avian animals of one species within the SPA. Additionally, 714 birds were partially identified to 10 species groups and four non-avian animals were partially identified to two species groups. An identification rate to species level of 97.57% was achieved throughout the survey. Shore-based surveys targeting common goldeneye (Bucephala clangula), goosander (Mergus merganser) and cormorant (Phalacrocorax carbo) recorded 1,150 birds between 10 and 15 February 2021, at six locations along the Cumbrian coast within the SPA boundary. Between the near-shore and marine areas, more birds were recorded in the near-shore area within 2 km of the coast. The most frequently recorded species from the digital aerial survey were dunlin (Calidris alpina), followed by common scoters (Melanitta nigra). For shore-based surveys, cormorants were the most frequently recorded species, recorded at Workington Harbour Wall.