Mallard

Anas platyrhynchos

Order: Anseriformes
Family: Anatidae
Presence in the Strait: Resident
Abundance: abundant
IUCN (global): LC · Least concern
In Spanish: Ánade azulón

Marine taxonomy: validated in WoRMS, AphiaID 148791

Photograph: anonymous, CC BY-SA, vía iNaturalist

Length: 51–62 cm
Wingspan: 81–98 cm
Weight: 1,000–1,150 g

Presence in the Strait

Abundant resident in wetlands. The most numerous breeding duck (>400 pairs), with a large increase during wintering (>7,500 birds).

Identification

The largest of the ducks, with a white-bordered blue speculum. Males have dark head and breast, pale grey central area and black stern. Females are similar to the female Gadwall but with an orange bill with black culmen and lacking a white belly.

Movements

Sedentary with short distance postgenerative dispersal. The 85 ringing recoveries come from Huelva and Seville.

Bioestrecho editorial text. Last revised: 8 September 2026.

Photographs from iNaturalist observations with the licence checked file by file. Those marked “Strait” were taken within the area; place and date are those of each observation.

Calendar in the Strait

15 %

Peak in April. Observations under CC0 or CC BY licences. The distribution also reflects observation effort.

Where it is seen

Open records from the atlas database, in cells of about 3.6 km. Opacity follows the square root of the count, and also reflects where people observe most.

See on the map

First open record: 2 May 1972
Latest record: 18 August 2026

The oldest and the most recent open observation in the extended area. A recent first observation does not mean the species is new: it means nobody had published it openly before.

Conservation

The catalogues, Andalusian and Spanish, are what binds; the Red Book assesses the Spanish population with IUCN criteria, and the global Red List is the context.

LCNTVUENCR

Andalusian Catalogue: Not included
Spanish Catalogue: Not included
Red Book of the Birds of Spain 2021: LC · Least concern · breeding — LC · Least concern · wintering or migrating
Global Red List (IUCN): LC · Least concern

Andalusian Catalogue: Junta de Andalucía, list of 24 April 2025. Spanish Catalogue: MITECO, table of 30 June 2025. Red Book: SEO/BirdLife, 2021 (Annex I). IUCN: via GBIF, 6 September 2026. Red Book and IUCN categories are assessments; catalogue categories are legal obligations.

Phenology compared

Monthly distribution in proportion, by decade. It shows whether the passage is getting earlier or later.

1990–1999

2000–2009

2010–2026

Proportions, not totals: observation effort grew faster than any population.

Same genus in the Strait

Northern Shoveler49–52 cm · Seasonal · overlapping size
Eurasian Wigeon45–51 cm · Seasonal · overlapping size
Northern Pintail61–76 cm · Seasonal · overlapping size
Gadwall46–56 cm · Presence to be confirmed · overlapping size
Garganey37–41 cm · Migrant

Species of the same genus that also occur here, ordered by how close they are in size. Being relatives does not mean they are confused in the field, but that is where the doubts start: compare size and season.

Classification

Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Anseriformes
Family: Anatidae
GBIF taxon key: 9761484

Sources

Distribution and calendar: Bioestrecho's own database, ingested from GBIF and OBIS
Photograph: anonymous, CC BY-SA, vía iNaturalist
Taxonomy: GBIF backbone, pending WoRMS for marine taxa
Editorial text: written by Bioestrecho
Last revised: 8 September 2026

Mallard

Presence in the Strait

Identification

Movements

Gallery