Red-breasted Merganser

• Its bill carries backward-pointing horny barbs that work like a saw and stop fish escaping once caught: hence the specific name serrator, "sawyer".
• It is a powerful flier that reaches 129 km/h in level flight.
• The Mar Menor has at times held between 20% and 40% of the Iberian wintering population and 5% of the world total.

Skeleton type

Vertebrate - internal bony skeleton (bird)

Habitat and environment

Coastal waters: rías, estuaries, bays and coastal lagoons. In Spain it appears above all on the Atlantic and Cantabrian coasts, as well as the Mar Menor, the Odiel marshes and the Ebro Delta

Birth weight

Precocial: born covered in down and leaves the nest within a few hours

Size at birth

Precocial: born covered in down and leaves the nest within a few hours

Sexual maturity

2 years

Gestation / incubation

32 days

Litter / clutch size

10

Sources consulted: SEO/BirdLife (ficha y III Atlas de las aves en época de reproducción en España); IUCN Red List; Asturnatura; Romay Cousido y Justo Álvarez 2022, III Atlas; Vera y Giménez en SEO/BirdLife 2012; Craik, Pearce y Titman 2020, Birds of the World; De Juana y García 2015

Best time: From November to mid-April, peaking in midwinter