HiDef Aerial Surveying Limited (“HiDef”) was commissioned by Natural England to undertake a second year’s monitoring of the distribution of European shag Phalacrocorax aristotelis at sea around the Isles of Scilly.
This report includes information from three ultra-high resolution digital video aerial surveys completed in 2015 and details the results of statistical analysis for seabirds and marine mammals observed, including estimates of abundance and density maps. Where appropriate, abundance estimates have been adjusted to account for availability bias. This provides an assessment of the true abundance rather than relative abundance for diving species. Behaviour information and flight direction has also been detailed for certain species.