|Scientific Name:||Deania hystricosa (Garman, 1906)|
Acanthidium hystricosum Garman, 1906
|Taxonomic Notes:||Bigelow and Schroeder (1957) synonymized this species with Deania calcea (as its synonym D. eglantina). Cadenat and Blache (1981) named a new species D. mauli, from Madeira, however D. mauli was later recognized as D. hystricosa by Garman (1906, 1913) and was tentatively synonymized with D. hystricosa by Compagno (1984). Compagno (1984) recognizes this species as separate from D. calcea. The characters that distinguish D. hystricosa from D. calcea need to be examined in more detail.|
|Red List Category & Criteria:||Data Deficient ver 3.1|
|Assessor(s):||Ebert, D., McCormack, C., Freitas, M., Biscoito, M., Francis, M., Tanaka, S., Ishihara, H., Holtzhausen, H. & Stewart, A.|
|Reviewer(s):||Valenti, S.V., Burgess, G., Cavanagh, R.D., Heupel, M. & Simpfendorfer, C. (Shark Red List Authority)|
The Rough Longnose Dogfish (Deania hystricosa) is a little known medium sized (to at least 111 cm total length) benthic and probably epibenthic deepwater shark known from depths of 471-1,900 m on the upper and middle continental and insular slopes off South Africa, Namibia, Madeira and possibly the Azores in the Atlantic Ocean, and off New Zealand and Japan in the Pacific Ocean. Taken by deepwater longline fisheries off Madeira and the Canary Islands, where it is utilized for its meat and liver oil. The species also occurs within the depth range of bottom trawl, longline, gillnet and tanglenet fisheries elsewhere in its range (i.e., Namibia, Japan) and may be taken as bycatch in these fisheries; however species-specific data are lacking. The lower portions of the species' deep depth distribution may offer it refuge from fishing pressure. At present there are no data with which to determine or infer population trends for this species and it cannot be assessed beyond Data Deficient. Furthermore, the characters that distinguish the Rough Longnose Dogfish from Shovelnose Spiny Dogfish (Deania calcea) need to be examined in more detail. Like other deepwater sharks, this species many be biologically vulnerable to population depletion. Bycatch levels in fisheries should be determined and monitored, especially as fisheries expand into deeper depths across the species range.
|Range Description:||Eastern central and southeast Atlantic: Madeira, possibly Azores, Canary Islands, Namibia, South Africa (Northern Province). Northwest Pacific: Japan and New Zealand (Compagno in prep.).|
May be wider ranging than currently known (Compagno in prep.).
Native:Japan; Namibia; New Zealand; Portugal (Madeira); South Africa (Northern Cape Province); Spain (Canary Is.)
|FAO Marine Fishing Areas:|
Atlantic – southeast; Mediterranean and Black Sea; Pacific – northwest; Pacific – southwest
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||In Madeira the species is common and was captured with bottom long-lines during two research cruises in 2004 and 2005 (Biscoito et al. in prep).|
Data from annual deepwater scientific research cruises conducted off Namibia from 2004-2006 (at 500-2,000 m depth), suggest that Deania hystricosa is the second most abundant shark (after Centroscymnus coelolepis) (H. Holtzhausen pers. obs. 2007). However, the biomass is small at ~2,625 tons throughout Namibian waters. The species is more abundant in the northern part of Namibia than in the south (H. Holtzhausen pers. obs. 2007).
The species is very rare in New Zealand with only one specimen known (A. Stewart pers. comm. 2006). There are about a dozen records of the species in a trawl survey database in New Zealand but these come from only three trips out of more than a hundred and it is believed that the database records are misidentifications of D. calcea (M. Francis pers. comm. 2006).
|Current Population Trend:||Unknown|
|Habitat and Ecology:||A little-known benthic and probably epibenthic dogfish of the upper and middle continental and insular slopes, at depths of 471-1,900 m (Compagno in prep, M. Freitas pers. obs. 2007, H. Holtzhausen pers. obs. 2007). Off Namibia, they are most common between 550 and 1,000 m depth, but are also found up to 1,900 m (H. Holtzhausen pers. obs. 2007). Attains a maximum total length (TL) of 111 cm (Compagno in prep.). Males are reported to mature at 81-84 cm and are adult at 84 cm (Compagno in prep.). Females mature at 92-106 cm and are adult at 106-109 cm (Compagno in prep.). Data from Madeira indicates that females range from 75-109 cm TL, while males ranged from 79-94 cm TL (Freitas and Biscoito in prep.). Reproduction is ovoviviparous (Compagno in prep.). Litter size is unknown however one female was found with 12 eggs suggesting a moderate litter size (Compagno in prep.).|
|Use and Trade:||Utilized for liver oil and meat.|
Rough Longnose Dogfish (Deania hystricosa) is caught minimally with deepset vertical longlines off Madeira, Porto Santo, Seine and Unicorn seamounts (Biscoito et al. in prep.) and off the Canary Islands, where it is utilized for liver oil and meat (Compagno in prep.). Off Madeira, this species is taken as bycatch in the Black Scabbardfish (Aphanopus carbo) fishery (operating at depths of 800 to 1,200 m) and used for human consumption (after drying it is reportedly similar to cod fish) and liver oil (M. Freitas pers. obs. 2007). No information on Deania hystricosa is available from the Azores where fishing occurs on the coastal areas, banks and seamounts (M.R. Pinho pers. comm. 2006). The Azores deep-water fishery is a multispecies and multigear fishery (ICES 2007). It is predominantly small-scale (vessels <12 m; 90% of the total fleet) using mainly traditional bottom longline and several types of hand lines operating down to 1,000 m depth and mainly between 200 and 600 m (ICES 2007).
Probably also caught as bycatch of deepwater fisheries elsewhere (Compagno in prep.). The species may be rarely caught by offshore bottom trawlers off Japan (S. Tanaka pers. obs. 2007).
The species is very rare in New Zealand (only one known specimen collected at 930 m; A. Stewart pers. comm. 2006) and the threat to this species from fisheries is probably negligible there (M. Francis pers. comm. 2006).
Off Namibia, a fairly small amount of demersal sharks are caught as bycatch by deep-water trawl fisheries and recorded as "sharks" or "other" (NATMIRC 2003). These fisheries target hake from 400-600 m off Central Namibia (around 100 vessels), monkfish at 600 m off Central Namibia (around 20 vessels) and orange roughy from 600-1,000 m off Northern Namibia (3 vessels) (NATMIRC 2003). Two vessels were also granted two-year exploratory rights to target deep-water shark species along the entire coast of Namibia using tanglenets (NATMIRC 2003). The main species of shark taken were Centrophorus squamosus, Centroscymnus coelolepis, Deania quadrispinosum, Squalus mitsukurii, Galeorhinus galeus. The exploratory directed deepwater licenses expired in January 2006.
There are no specific management measures in place for this species. The use of fixed gillnets at depths of over 200 m has been banned in the archipelagos of the Azores, Madeira and the Canary Islands (ICES 2007).
Like many deeper water species more information on biology, ecology and importance in fisheries are required to further assess status and any future conservation needs. Where taken, catches require monitoring, particularly as deepwater fisheries expand worldwide.
|Citation:||Ebert, D., McCormack, C., Freitas, M., Biscoito, M., Francis, M., Tanaka, S., Ishihara, H., Holtzhausen, H. & Stewart, A. 2009. Deania hystricosa. The IUCN Red List of Threatened Species 2009: e.T161549A5449034.Downloaded on 21 January 2018.|