Nursehound

What it is

This shark has a stout body that tapers toward the tail and a broad, rounded head. Its skin feels very rough due to large, upright dermal denticles. The colour varies from greyish to brownish, covered in small black dots and larger brown spots. Two dorsal fins sit far back on the body, with the first being larger than the second. The eyes are oval and lack a nictitating membrane, while nasal flaps do not reach the mouth.

Where it lives

It lives in the northeastern Atlantic, ranging from southern Norway and Sweden down to Senegal. Populations exist around the British Isles, the Mediterranean Sea, and the Canary Islands. Records near the Congo River may be misidentifications. The species prefers quiet water over rocky terrain or algae-covered coral. It inhabits depths from the intertidal zone to 400 metres, though it is most common between 20 and 125 metres.

How it lives

Primarily nocturnal, these sharks hide in small rock holes during the day. They often share refuges with others of their kind and may move between several sites. At night, they swim into deeper water to hunt benthic organisms. Their diet includes bony fish like mackerel and herring, crabs, shrimp, cephalopods, and smaller sharks. Adults eat more fish and cephalopods than juveniles do. They are known to scavenge when the opportunity arises.

Breeding and life cycle

Females lay eggs from March to October in shallow coastal waters. Each egg case is thick, dark brown, and secured to seaweed using corner tendrils. A female produces many oocytes but lays between 9 and 41 eggs annually. Incubation lasts seven months in the southern Mediterranean and up to a year in the North Sea. Hatchlings measure about 10 to 16 cm and grow slowly. Sexual maturity occurs at around four years of age.

Fish and people

Fishers market the meat fresh, dried, or salted under names like rock salmon or flake. Historically, its rough skin, called rubskin, was valued as an abrasive for polishing wood and smoothing arrows. The liver provided oil, and carcasses were used as crab bait. Today, it appears in public aquariums and is caught using trawls and nets. France, the UK, and Portugal lead commercial production in European waters.

Status and threats

The International Union for Conservation of Nature lists this species as Vulnerable. Populations have declined substantially in the Mediterranean, including the Gulf of Lion and around the Balearic Islands. In the upper Tyrrhenian Sea, numbers have dropped by over 99 per cent since the 1970s. Overfishing poses a significant threat because the shark grows slowly and has a fragmented distribution, which limits stock recovery.

Questions people ask about Nursehound

Good reading and sources

• Nursehound on WikipediaEncyclopedia
• More photos on Wikimedia CommonsPhotos
• Wikidata recordOpen data