Great Northern Diver Welfare as a Winter Visitor

The great northern diver is an impressive seabird that winters on UK coasts and lochs after breeding on subarctic lakes in Iceland and Greenland.

Key Facts

Great northern divers winter on sheltered sea lochs, coastal bays, and occasionally inland reservoirs
Annual UK wintering numbers estimated at around 2500 birds
Breed on freshwater lakes in Iceland, Greenland, and northern North America
Remarkable diving ability with dives exceeding 70 metres recorded
Plumage changes from breeding to winter cause significant appearance differences

Welfare Considerations

Great northern diver welfare during UK winters depends on undisturbed access to productive coastal waters with abundant fish. Disturbance from boat traffic and water sports causes repeated flushing that depletes energy reserves. Oil pollution causes feather damage that destroys waterproofing with lethal consequences. Lead poisoning from ingesting lead fishing weights and line is documented in divers. Entanglement in fishing nets is a mortality cause. The winter period is critical for divers to maintain body condition for the return migration and breeding season. Sheltered sea lochs in Scotland provide important wintering habitat where disturbance management is feasible.

What You Can Do

Maintain large distances from divers when boating in sea lochs during winter months
Report oiled or injured great northern divers to wildlife rehabilitation centres
Advocate for lead fishing tackle bans to reduce poisoning risk for diving waterbirds
Record great northern diver winter sightings for WeBS waterbird monitoring