Northern Harrier

Circus cyaneus

Order: Accipitriformes
Family: Accipitridae
Presence in the Strait: Seasonal
Abundance: scarce
Protection in Spain: Special protection (List)
In Spanish: Aguilucho pálido

Photograph: Gregory "Slobirdr" Smith, CC BY-SA, vía iNaturalist

Length: 43–50 cm
Wingspan: 100–120 cm
Weight: 440–500 g

Presence in the Strait

Scarce winter visitor to grasslands and farmlands (>27).

Identification

Males, blue-grey, paler below with black wing tips. Females are dark brown on upperparts and paler underparts which are streaked and barred. Juveniles are similar to females but more rufous-yellow underparts and less streaks. Adults and juveniles have white rumps.

Movements

Scarce migrant (>100 post. migr.) with peaks in 2nd hf. March and 1st hf. October.

Ring recoveries

France (1).

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

19 %

Peak in December. 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: 5 October 1980
Latest record: 29 December 2024

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: Special protection (List)
Spanish Catalogue: Special protection (List)
Red Book of the Birds of Spain 2021: EN · Endangered · breeding
Global Red List (IUCN): LC · Least concern

Annex I of the Birds Directive

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.

2000–2009

2010–2026

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

Where they come from

1 birds ringed in other countries and recovered in the area.

France1

See the journey on the map

Same genus in the Strait

Montagu´s Harrier43–50 cm · Seasonal · overlapping size
Pallid Harrier40–50 cm · Seasonal · overlapping size
Westhern Marsh Harrier48–55 cm · Seasonal · overlapping size

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: Accipitriformes
Family: Accipitridae
GBIF taxon key: 2480487

Sources

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

Northern Harrier

Presence in the Strait

Identification

Movements

Ring recoveries

Gallery