The gannet is Britain's largest seabird, with the Bass Rock supporting the world's largest single colony. Their welfare depends on North Sea fish stocks and colony site protection.
Gannets in colonies near depleted fish stocks must travel further for food, increasing energy expenditure and reducing chick provisioning rates. Plastic ingestion causes gastrointestinal blockage and starvation. Entanglement in discarded fishing gear causes drowning and rope injuries. Climate-driven shifts in sand eel and herring distribution affect foraging efficiency in ways that compound naturally variable breeding years. Individual gannets affected by marine litter or entanglement suffer acute welfare costs that are difficult to quantify but visible to colony monitors.