true

ISRA FACTSHEETS

EUROPEAN ATLANTIC

ISRA FACTSHEETS

EUROPEAN ATLANTIC

Avilés-Colunga ISRA

66/124

Avilés-Colunga ISRA

Avilés-Colunga

Summary

Avilés-Colunga is located along the Asturian coast, in the Cantabrian Sea, Spain. It encompasses rocky coasts, with cliffs and narrow beaches, several estuaries, and a narrow continental shelf. The area is characterised by rocky outcrops, sandy patches, and muddy substrates. It is influenced by the interaction of topographic features, riverine inputs, seasonal stratification, and recurrent upwelling. The area overlaps with the Cantabrian Sea (Southern Bay of Biscay) Ecologically or Biologically Significant Marine Area and the Cabo Busto – Luanco Key Biodiversity Area. Within this area there are: threatened species (e.g., Nursehound Scyliorhinus stellaris); and reproductive areas (e.g., Undulate Skate Raja undulata).

Avilés-Colunga

Avilés-Colunga

DESCRIPTION OF HABITAT

Avilés-Colunga is located along the Asturian coast, in the Cantabrian Sea, Spain. It encompasses rocky coasts, with cliffs and narrow beaches, several estuaries, and an adjacent narrow continental shelf. Avilés-Colunga is a split area encompassing Santa Marina to Faro de Peñas in the west and Faro de Lastres to La Vega to the east. The area is characterised by mixed substrates comprising rocky outcrops, sandy patches, and occasional muddy deposits (Flor et al. 2022).

The area is influenced by the interaction of topographic features, riverine inputs, seasonal stratification, and recurrent upwelling. Dynamic mesoscale events occur seasonally as shelf-break fronts along the shelf edge that concentrates planktonic biomass and occasional slope water eddies (Albaina & Irigoien 2004). During the boreal winter, the water column is fully mixed due to storm-driven turbulence, while in summer, thermal stratification develops, often interrupted by upwelling events (Mason et al. 2006). These wind-driven upwellings, particularly prominent during summer months, inject cold, nutrient-rich waters onto the shelf, enhancing primary production and supporting diverse plankton communities (Mason et al. 2006).

This area overlaps with the Cantabrian Sea (Southern Bay of Biscay) Ecologically or Biologically Significant Marine Area (EBSA; CBD 2025); and the Cabo Busto – Luanco Key Biodiversity Area (KBA; KBA 2025).

This Important Shark and Ray Area is benthic and pelagic and is delineated from inshore and surface waters (0 m) to 200 m based on the bathymetry of the area.

CRITERION A

VULNERABILITY

Two Qualifying Species considered threatened with extinction according to the IUCN Red List of Threatened Species regularly occur in the area. These are the Critically Endangered Tope (Walker et al. 2020) and the Vulnerable Nursehound (Finucci et al. 2021).

CRITERION C

SUB-CRITERION C1 – REPRODUCTIVE AREAS

Avilés-Colunga is an important reproductive area for two shark and one ray species.

Between 2022–2025, pregnant female Tope were reported in the area from interviews with artisanal fishers (L Miralles López unpubl. data 2025). A total of 10 informal interviews were conducted with fishers using gillnets and small trawlers in the area and adjacent waters (L Miralles López unpubl. data 2025). Of these, eight fishers reported capturing pregnant Tope during January–May each year. Adult females represent most of the captures from October–January (close to the 90% of all Tope captures in the area) and from January–May, pregnant females aborted embryos of 20–25 cm total length (TL) on the boat when captured. Pregnant females represented 50% of the females during January–May, and one out of five Tope individuals (L Miralles López unpubl. data 2025). Size-at-birth for the species is 30–40 cm TL (Ebert et al. 2021), indicating that embryos were near-term.  Additionally, between October 2024–January 2025, 10 random Tope were collected and sampled at Avilés landing site within the area, of which nine were pregnant females measuring 142–158 cm TL, with litters ranging from 6–30 early-stage embryos, measuring between 10–15 cm TL (L Miralles López unpubl. data 2025). Captures of the species are scarce along the north coast of Spain (Rodríguez-Cabello et al. 2005; Fernández-Zapico et al. 2021); however, pregnant females have been reported in the area regularly and predictably over the years (L Miralles López unpubl. data 2025).

Beach-washed egg cases of Nursehound and Undulate Skate were regularly and predictably reported from this area during beach surveys between 2022–2024 (González Díaz 2024; AI García Muñoz & L Miralles López unpubl. data 2024). Egg case identification was confirmed through species-specific guides (AI García Muñoz & L Miralles López unpubl. data 2024). Between November 2022–January 2024, surveys consisted of walks along 17 beaches across Asturias Province during low tide looking for egg cases in the intertidal zone of the beach during winter and spring months (November to May). A total of 24 survey days were conducted across various beaches, which were randomly selected. These observations were supported by in situ records and opportunistic dissections of egg-carrying females.

Between 2013–2021, Nursehound neonates, young-of-the-year (YOY), and small juveniles ranging in size 16–52 cm TL were captured in the area during the Northern Spanish Shelf Groundfish Survey, using 30 min trawl surveys (Blanco et al. 2022; Ruiz-Pico et al. 2024). Size-at-birth for the species is 10–16 cm TL and size-at-maturity is reached between 70–79 cm TL (Ebert et al. 2021), indicating that all sharks were immature. This area is of particular importance because, although captures of the species along the north coast of Spain are scarce, neonates, YOY, and small juveniles have been consistently recorded in the area including the highest catches of up 8 kg of Nursehound in a 30-min haul (Blanco et al. 2022; Ruiz-Pico et al. 2024). Further, a total of 33 Nursehound egg cases (all confirmed as hatched) were collected from this area (69% of the 48 egg cases collected across Asturias Province) with observations recorded during 2022 (n = 12), 2023 (n = 6), and 2024 (n = 15) (González Díaz 2024; AI García Muñoz & L Miralles López unpubl. data 2024). Between 2020–2025, in situ records of egg with embryos inside were reported during the red algae collection season in the area in August–September and by fishers in August of 2020 (n = 2), August 2021 (n = 1), September 2023 (n = 1), and August 2025 (n = 1) at depths ranging from 10–12 m (L Miralles López unpubl. data 2025; Surfistas Vigilantes del Mar pers. comm. 2025). Additionally in the area, the presence of females carrying eggs has been confirmed by fishers when preparing the sharks for landing in Avilés fish market between 2022–2025, as well as by the dissections of two females carrying eggs out of 10 individuals examined in the area from September 2024 to January 2025 (L Miralles López unpubl. data 2025). Although Nursehound egg cases from adjacent areas have been collected, this area has the largest observations of egg cases of this species on the Cantabrian coast.

A total of 97 egg cases of Undulate Skate (all but one with a near term embryo confirmed as hatched) were collected from this area (84% of the 115 egg cases collected across Asturias Province) and these observations were recorded during 2022–2023 (n = 67) and 2024 (n = 30) (González Díaz 2024; AI García Muñoz & L Miralles López unpubl. data 2024). Additionally in the area, the presence of females carrying eggs have been confirmed by fishers when preparing the sharks for landing in Avilés fish market between 2022–2025, as well as by dissections of three out of 14 individuals examined in the area in January 2025 (L Miralles López unpubl. data 2025). Although Undulate Skate egg cases from adjacent areas have been collected, this area has the largest observations of egg cases of this species on the Cantabrian coast.

Avilés-Colunga

SUBMIT A REQUEST

ISRA SPATIAL LAYER REQUEST

To make a request to download the ISRA Layer in either a GIS compatible Shapefile (.shp) or Google Earth compatible Keyhole Markup Language Zipped file (.kmz) please complete the following form. We will review your request and send the download details to you. We will endeavor to send you the requested files as soon as we can. However, please note that this is not an automated process, and before requests are responded to, they undergo internal review and authorization. As such, requests normally take 5–10 working days to process.

Should you have questions about the data or process, please do not hesitate to contact us.

    * indicates required

    Industry or sector (*)

    Under the terms and conditions of our User License Agreement , full and appropriate acknowledgement is required in any materials and publications derived from the data (and copies should be sent to the IUCN SSC Shark Specialist Group through the contact form). For any publications making substantial use of the data, the ISRA welcomes the opportunity for co-authorship, collaboration, and to comment prior to publication.


    Furthermore, we need to know whether you are a commercial or non-commercial user. Non-commercial includes scientific research, education or conservation. Commercial is defined as follows: any use by, on behalf of, or to inform or assist the activities of a commercial entity (that operates ‘for profit’) or use by a non-profit for the purposes of revenue generation

    Type of use(*):

    Please specify which layer (ex. all layers, layers within a specific Region, layers within a Jurisdiction or a single ISRA): Purpose (*):

    Please provide a description of how you intend to use the ISRA GIS Dataset. The more details you provide, the faster we can respond to your request. We may require further clarification prior to providing access. (min. 100 characters – max 1,000 characters)



    File format request (*)

    By providing your personal data, you consent to its processing as described below. The IUCN SSC Shark Specialist Group will use the information you provide on this form to send the documents you requested. You can change your mind at any time by writing to the ISRA Data Coordinator www.sharkrayareas.org/contact. All personal details provided will be treated with respect. For any information you can visit our Privacy Policy.
    Please read the User License Agreement and ISRA Layer Metadata Description

    This form uses Google reCaptcha to reduce spam. Privacy - Terms