Topic: Tope

Characteristic features

The tope (Galeorhinus galeus) is a relatively small shark in the Family Triakidae. It has a slender, streamlined body of up to 2 m and a long snout. It is similar in appearance to the spurdog, but can easily be identified by its lack of dorsal spines. It has a greyish dorsal surface and pale ventral surface. It also has a characteristic lobe protruding from the top half of the caudal fin.

This shark has a wide distribution, occurring on the continental shelves and slopes in temperate waters around the world. It is divided into several populations, and one of these occurs in the Northeast Atlantic from Western Africa and the Mediterranean to Iceland and southwestern Norwegian waters.

Biology

The tope is a benthopelagic shark, meaning it is often associated to the seafloor but also ventures into pelagic waters. It uses a wide range of depths from shallow coastal waters to deep waters down to 800 m. It feeds on a variety of prey, including schooling fish, cephalopods, and bottom-associated animals like crustaceans. The tope is ovoviviparous and gives birth to 20–50 pups after a long gestation period of around 10–12 months.

This shark’s movement and migratory behaviour are complex, and are thought to vary between genders and with age. It is an active swimmer and has been known to undertake long-distance migrations of up to several thousand kilometres. They can also be found in large aggregations. Young tope primarily remain in shallow waters near the coast for a few years before they begin to venture offshore and explore greater depths.

Fishery and management

The tope is of significant commercial value in some parts of the world. Its meat is still consumed, and its fins are used in shark fin soup in some countries. This shark is therefore known by other names including ‘soupfin shark’. It is also sold as ‘rock salmon’, and as ‘flake’ in Fish and Chips shops in the southern hemisphere. It was also previously referred to as ‘vitamin shark’ because of its oily liver that was used as a source of Vitamin A until the 1940s, when it was replaced with synthetic alternatives.

Today, tope is of low commercial value in Europe, and it is not a target species. However, it is caught as bycatch in several fisheries, and this bycatch is either discarded to landed for consumption in southern parts of Europe. Tope is also a popular target for recreational anglers, mainly in the British Isles.

Tope is classed as Critically Endangered globally and Vulnerable in European waters (IUCN Red Lists).