Black-throated Diver

• Its bones are partly solid, unlike the hollow bones of almost all birds: that density reduces buoyancy and lets it dive effortlessly, but it means a take-off run of tens of metres across the water.
• On land it is almost helpless: its legs are set so far back that it cannot walk upright, and it nests within a metre of the shore because it cannot get any further.
• The chicks ride on their parents' backs for the first few weeks, sheltered from the cold water and from large fish and raptors.

Skeleton type

Vertebrate - internal bony skeleton (bird)

Habitat and environment

Deep lakes of the taiga and tundra for breeding; sea coasts and bays for wintering

Sexual maturity

3 years

Gestation / incubation

29 days

Litter / clutch size

1.74 (average)

Sources consulted: Wikipedia (es): Gavia arctica

The pins mark the parks where its presence is documented.