The tope shark is a relatively small cartilaginous fish which is found in temperate and boreal waters with the exception of the Northwest Atlantic and Northwest Pacific. Tope were formerly common in Northern Ireland waters but are now much reduced in numbers probably as a result of being taken as a by-catch in commercial fishing. Tope are eagerly sought after by many sea anglers, some specialising in tope fishing. As the developing eggs are held in the mother’s body for one year, tope are vulnerable to capture of pregnant females, especially when these come inshore to give birth. This, coupled with late maturity, means that the population has a low rate of increase and is vulnerable to overfishing.

In brief

• Found in the seas around Northern Ireland.
• Bottom dwelling in relatively shallow sea (< 200 m) with gravel or sandy bottom.
• Most likely to be seen when females come inshore in summer to give birth.
• Has declined in recent years.
• Main threat is overexploitation, especially of pregnant females, by angling and commercial fishing.

Species description: Tope are small sharks growing to a length of about 1.5 metres and 40 kg in weight. As with other sharks, the tope has five external gill slits behind the mouth and a tail fin with the upper lobe being larger than the lower one. The tope is a uniform grey colour above, and white beneath, with a long, pointed and flattened snout, and well-developed typical shark cutting teeth. It has a distinct hole (spiracle) behind the eye. They are solitary, although sometimes small shoals occur, and generally live in relatively shallow water.

Life cycle: Tope are long-lived (up to 50 years) and do not reproduce until they are about 12 years old, and thereafter every 2-3 years. Fertilisation is internal, the male using his claspers to introduce sperm, and the developing eggs (5 to 20+ depending on female size) are retained within the mother’s body (ovoviviparous reproduction) for about one year. Newly-born young (c.30cm in length) aggregate in nursery areas such as Strangford and Carlingford Loughs but move into deeper waters in winter. The species is highly migratory with tope tagged in south-west Scotland being recaptured as far away as the Canary Islands and Iceland.

Similar species: Tope may be confused with other smallish sharks (for example, smooth hounds and dogfish) but its uniform grey colour and absence of white spots, well developed pointed teeth, large spiracle, and absence of spines on dorsal fins helps to distinguish it.

How to see this species: Most likely to be seen when females come inshore in summer to give birth in places such as Strangford Lough and Carlingford Lough. Tope are sometimes kept in public aquaria.

Current status: Vulnerable and declining. Data deficient. Classified as Vulnerable on IUCN Red List. The tope is found around the coasts of Northern Ireland, previously including Strangford and Carlingford Loughs, where females came to give birth to their ‘pups’. No accurate information is available on current numbers in waters around Northern Ireland, although the number of larger tope taken by anglers appears to have declined in recent years. A similar situation applies to the rest of the north-east Atlantic where there is insufficient data to determine accurately its current status.

Why is this species a priority in Northern Ireland?

• Criterion 1: Internationally listed species.
• Criterion 2: Decline based on available data and expert judgement.
• Criterion 4: NI stronghold or endemic – both stronghold range/population and designation as ‘endemic’ subject to expert judgement.

Threats: Main threat is overexploitation, especially of pregnant females, by angling and commercial fishing, where it is mainly taken as a by-catch in fisheries for other species. Development of a targeted commercial fishery has been proposed recently in England. Habitat degradation in nursery areas may have an adverse impact.

Action: Records of new sites for this species, with details of habitat and population are always valuable. Observations with a photograph can be recorded using iNaturalist, find the MBDP-NI iNaturalist project here.

Alternatively, records can be sent to CEDaR, National Museums Northern Ireland, 153 Bangor Road, Cultra, Holywood, County Down, BT18 0EU. Tel 028 9039 5257, e-mail cedar.records@nationalmuseumsni.org, or via the online portal.

Objectives:

• The status of tope will be surveyed and monitored and appropriate conservation action taken if required
• Determine tope nursery areas in local waters and designate protection for these
• Develop, with angling associations, a code of conduct for catch-and-release of tope, and other vulnerable elasmobranchs, and for reporting catch and other data.
• Avoid eating this species, which is often used for shark fin soup, to discourage commercial capture.
• All anglers should practise catch-and-release, which is already practised by most recreational anglers.

Conservation:

• Listed as Critically Endangered on Global IUCN Red List, and Vulnerable on European Red List.
• Strangford Lough is a Marine Protected Area with multiple designations, although some forms of fishing are still permitted.

Distribution Map from NBN: Galeorhinus galeus at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Galeorhinus galeus at iNaturalist World Species Observations database.

WoRMS: Galeorhinus galeus at World Register of Marine Species. Accepted name: Galeorhinus galeus (Linnaeus, 1758). AphiaID: 105820.

Classification: Biota; Animalia; Chordata; Vertebrata; Gnathostomata; Chondrichthyes; Elasmobranchii; Neoselachii; Selachii; Galeomorphi; Carcharhiniformes; Triakidae; Galeorhininae; Galeorhinus