The provision of fish offal for supplementary feeding at sea may benefit some seabirds and could be specifically targeted to improve the productivity and survival of certain species. This report provides an overview of offal production at sea to understand current practices, quantities, and composition. It includes considerations for at-sea offal retention, including logistical, legal, health and safety, and costs, and highlights knowledge gaps.
The estimated quantity of at-sea offal production is almost 28 thousand tonnes per year from all UK fishing areas. The North Sea is the main source of at-sea offal (41%) with nearly 11.5 thousand tonnes produced across the three areas: The northern North Sea; central North Sea and the southern North Sea.
A case study based on the black-legged kittiwake (Rissa tridactyla) breeding at the Flamborough and Filey Coast Special Protection Area (FFC SPA) is used to consider whether at-sea offal is a potential source for supplementary seabird feeding. Three scenarios were developed ranging from minimal intervention compared to current practice through to significant additional activities.
To ensure at-sea offal is available for supplementary feeding of seabirds on a substantial level, changes to current practice would be required. Based on the findings in this report, this would include aggregation of offal, either on land or transhipped at sea. The case-study presented in this report shows that land-based aggregation of offal may be advantageous as it would provide access to a larger quantity of material compared with the quantities that may be available from just the local fleet.