Sharks and Skates of Scotland Report: Black roughscale catshark (Apristurus melanoasper)

An extract from the Sharks and Skates of Scotland Report.

Black roughscale catshark - Apristurus melanoasper (Iglésias, Nakaya & Stehmann, 2004)

Population status

Scotland and Northeast Atlantic: Unknown (Neat et al., 2015; Walls, 2015).

Global: Stable (Finucci et al., 2024).

Note: Due to problems with the identification of this species in years prior to 2007, the data were insufficient to model temporal variation in the Rockall Trough, west of Scotland (Neat et al., 2015).

Conservation listings

• IUCN Red List Global: Least Concern (assessment 17 November 2014)
• IUCN Red List Europe: Least Concern (assessment 07 July 2023)
• CITES: Not listed
• CMS: Not listed
• OSPAR: Not listed
• Listed on the UK’s ‘Prohibited Species’ list as documented in the ‘Written Record of fisheries consultations between the United Kingdom and the European Union for 2025’ for UK waters of ICES Subareas 5-10
• Zero TAC under EU Regulation 2018/2025 & EU Regulation 2023/194
• Prohibited under EU Regulation 2025/202
• Listed on The Sharks, Skates and Rays (Prohibition of Fishing, Trans-shipment and Landing) (Scotland) Order 2012.
• Included in the NEAFC measures prohibiting directed fishing for deep-sea sharks

Range and distribution 

Black roughscale catshark are found in the Northwest Atlantic, the Southeastern Atlantic (Namibia), the central Indian Ocean and south of Madagascar, and in the Western South Pacific (Australia, New Zealand, and New Caledonia and surrounding seamounts) (Ebert & Stehmann, 2013). In the Northeast Atlantic, Black roughscale catsharks occur in deep-water off the Faroes, British Isles, Ireland and France (Ebert & Stehmann, 2013).

Habitat 

This species lives on continental mid-slopes and seamounts, and have been recorded at depths of 512-1900 m, but mostly below 1000 m (Iglésias et al., 2004; Nakaya et al., 2008; Neat et al., 2015). In groundfish surveys in the Porcupine Seabight a few specimens were found at depths below 1000m (Fernández-Zapico et al., 2023). While in surveys of the Rockall Trough, west of Scotland, the species was found regularly throughout the area at depths ranging of 1000 – 1900 m (Neat et al., 2015).

Biology and Ecology

The Black roughscale catshark is a medium-sized deep-water catshark species, with a maximum total length of 79 cm (Iglésias et al., 2004). There is a lack of information on the biology and ecology of this species, and data is only available from a small number of specimens. Males and females are generally sexually mature at 60 cm total length or greater. An oviparous species, the Black roughscale catshark produces egg cases of ≃ 6 cm in length with two very long, coiled tendrils positioned close together at the base (Iglésias et al., 2004).

Human interactions 

Black roughscale catshark has been subject to a zero Total Allowable Catch in the Northeast Atlantic since 2010 (ICES, 2024), and since 2021 has been a prohibited species. Apristurus spp are prohibited species in UK, EU and international waters of ICES subareas 5-10 and 12 and vessels are prohibited from landing this species in Scottish waters. The species is generally found in water deeper than 1000 m, which offers some refuge from fishing pressure.