|Scientific Name:||Odontaspis ferox|
|Species Authority:||(Risso, 1810)|
|Infra-specific Taxa Assessed:|
Carcharias ferox (Risso, 1810)
Odontapsis herbsti (Whitley 1950)
Squalus ferox Risso, 1810
|Taxonomic Notes:||The species was first described by Risso (1810) as Squalus ferox from the type locality at Nice and most early records were from the Mediterranean and eastern North Atlantic. Whitley (1950) described O. herbsti from south-eastern Australia, differentiating it from O. ferox mainly on differences in dental formulae, and the absence of pigment spots. Garrick's (1974) account of two specimens from New Zealand cast doubt on any differences in dentition between the species but retained O. herbsti for the plain-coloured Odontaspis. However, Compagno (1984) reviewed the two species and considered that O. herbsti was a junior synonym of O. ferox, noting (as did Robins et al. 1980) that the presence or absence of spots was highly variable, much as with Carcharias taurus. The existence of spotted specimens outside the Mediterranean Sea, including from California (Seigel and Compagno 1987), is supported by in-situ observations made off Lebanon, New Zealand and Malpelo Island (Columbia), where specimens exhibit considerable variability in the presence, density and size of spots. There may be some regionalised trends controlling the intensity of such pigmentation. In the absence of any further evidence to support the validity of an O. ferox / O. herbsti dichotomy, recognition of the single Odontaspis ferox of Risso, as previously argued by Compagno (1984, 2001), remains valid.|
|Red List Category & Criteria:||Vulnerable A2bd+4bd ver 3.1|
|Assessor(s):||Pollard, D., Gordon, I., Williams, S., Flaherty, A., Fergusson, I.K., Dicken, M. & Graham, K.|
|Reviewer(s):||Cavanagh, R.D., Valenti, S.V., Dudley, S., Soldo, A. & Francis, M. (Shark Red List Authority)|
Despite its extensive, almost worldwide, distribution, Smalltooth Sand Tiger Shark (Odontaspis ferox) populations and occurrences are fragmented and the species may be naturally rare. This species is morphologically very similar to Carcharias taurus, although it is larger and bulkier and is presumed to have a very low reproductive capacity, similar to that of C. taurus (producing only two pups every two years). This likely very low reproductive capacity makes it potentially susceptible to local extirpation, even at seemingly small capture rates. Although probably not specifically targeted, there are commercial landings of the species taken in bottom trawls, set-nets and line gear in many areas including the Mediterranean Sea, Japan, and occasionally Australia (although it is now protected in New South Wales). It is generally found in deeper water (down to 880 m depth), but recent observations of small aggregations in shallow water in a number of areas (Mediterranean Sea and Eastern Pacific Ocean) suggests that the species may be more vulnerable to fishing pressure than previously assumed, and potentially susceptible to coastal habitat impacts, similar to C. taurus. Increased demersal trawl fisheries in Australia and New Zealand are now operating in areas of possible and known occurrence. Fishery independent surveys indicate a decline of over 50% in catches off the east coast of Australia (hence the Vulnerable assessment in those waters), probably the result of commercial fishing operations off New South Wales. Similar declines are presumed to have occurred in other parts of its range impacted by fisheries. Given the species' likely very low reproductive capacity, intensive fishing pressure throughout its bathymetric range in the Mediterranean Sea and an absence of management measures there, the decline of O. ferox in this region is suspected to match or even exceed that in Australia, warranting a regional assessment of Endangered. There are very few records from subequatorial Africa, where the species is currently assessed as Data Deficient. Globally, a precautionary assessment of Vulnerable is considered appropriate, as a result of documented and suspected declines, the species' apparent rarity, presumed very low fecundity and high vulnerability to exploitation, and continued by-catch in fisheries.
|Range Description:||Records show a very disjunct distribution throughout most of the world's oceans. Overall, the latitudinal range of O. ferox is between 46oN in the Bay of Biscay (Debrosses 1930) to around 38-39oS in the Indian and Pacific Oceans. Recorded in the Northeast Atlantic Ocean, the Indian Ocean (including the Cocos-Keeling Islands (Australian Territory)), and the Western Pacific, Central Pacific and Northeast Pacific Oceans.
The first record for the Northwest Atlantic Ocean was in 1989 (Bonfil 1995) and voucher specimens have also been recorded off North Carolina (USA) and Mexico (in the North West and West Central Atlantic). The species has also been reported from Brazil in the South West Atlantic; the first record was based on jaws collected by fishers off Natal, Rio Grande do Norte (Menni et al. 1995, Soto 2001) and there are subsequent records from the Archipelago of Fernando de Noronha (03°52'S, 32°25'W) off north-eastern Brazil (Garla and Garcia Jr. 2006). In the Northeast and East Central Atlantic, O. ferox has been recorded from the Bay of Biscay, Madeira, Azores, Canary Islands, Morocco, Western Sahara and widespread in the Mediterranean Sea. In the Indian Ocean, from South Africa (KwaZulu-Natal), northeast and southeast of Madagascar in open ocean, Tanzania, El Dabra in the Mozambique Channel, Madagascar, Maldives, open ocean southeast of Sri Lanka, southwest of Sumatra and Cocos-Keeling Islands (Compagno 2001). In the Western Pacific, from Japan, Australia (New South Wales, eastern Victoria), New Zealand (North Island) and the Kermadec Islands (Fergusson et al. 2008), although it is probably more widespread in north-eastern Australian waters than voucher specimens would indicate (P. Last, pers. comm.). In 2004, a large female was caught by an orange roughy trawler in 880m on the Louisville Ridge over 600 nm east of New Zealand (M. Francis, pers. comm.). In the Central and Eastern Pacific, from the Hawaiian Islands, southern California (USA), Mexico and Colombia (Compagno 2001). Photographs taken by divers at Malpelo Island off Columbia have also confirmed the presence of O. ferox in the Gulf of Panama. Diver sightings have also been reported on isolated deep reefs in various other locations.
In the Mediterranean there are published records from Spain and the Balearic Islands (Lozano Rey 1928), Algeria (Moreau 1881, Dieuzeide et al. 1953), northern Tunisia (Capapé et al. 1975), Italy (Giglioli 1880, Tortonese 1956, Vacchi and Serena 1997), Pelagic Islands (Zava and Montagna 1992), the Adriatic Sea (Soljan 1975, Morovic 1976, Soldo and Jardas 2002), Greece and the Aegean Sea (Economidis 1973, Papaconstantinou 1988), and Lebanon (George et al. 1964, Ben-Tuvia 1971, Mouneimne 1977). Mediterranean sites apparently favoured by O. ferox are typically located either along the coasts of islands lying contiguous to deepwater, near offshore seamounts or at mainland localities where continental shelves are narrow, e.g., within the Tyrrhenian Sea, around Sicily, off south-western Malta, off Lebanon, off the southern coast of Cyprus, and around the Dodecanese and Cyclades island groups of the Aegean Sea. Originally recorded off Lebanon by George et al. (1964), O. ferox is now repeatedly observed by divers near Beirut, where it had previously been misidentified as Carcharias taurus. The status of this shark in North African waters of the Mediterranean is patchily known. A small number of specimens are reported and confirmed by preserved dentition from Algerian fisheries (F. Hemida, USTHB/ISN, Algiers, pers. comm.), and literature and contemporary records for Tunisia are equally scant (Capapé et al. 1976). However, specimens are likely still landed at Tunisian ports, from fisheries operating throughout the Sicilian Channel. There is no contemporary data for this species in Libyan or Egyptian waters but it may occur in the slope waters of the southern Levantine Basin.
In South Africa this species is known from a few juvenile specimens recorded from trawls on the outer edges of the continental shelf, off the east coast (Natal) (Bass 1978). Small numbers were observed caught on longline gear at about ~300 m along the south KwaZulu Natal coast, South Africa, in the late 1980's, and further anecdotal information indicates relatively frequent capture of these sharks (of approx 2 m TL) during target fishing for deep-sea sharks and rays (D. Ebert, pers. comm. 2004). Forster et al. (1970) caught what appears to be a large female of O. ferox in deep water off the northeast of Madagascar. There have been unconfirmed, but reliable, reports of sightings of small aggregations of O. ferox around deepwater drop-offs off the Transkei coast in South Africa by divers.
Native:Algeria; Australia (New South Wales, Victoria, Western Australia); Brazil (Fernando de Noronha, Rio Grande do Norte); Cocos (Keeling) Islands; Colombia (Malpelo I.); Cyprus; France; Greece; Italy (Italy (mainland)); Japan (Honshu); Lebanon; Maldives; Malta; Mexico; Morocco; New Zealand (Kermadec Is., North Is.); Portugal (Azores, Madeira); South Africa (KwaZulu-Natal); Spain (Baleares, Canary Is., Spain (mainland)); Sri Lanka; Tanzania, United Republic of; Tunisia; Turkey; United States (California, Florida, Georgia, Hawaiian Is., North Carolina, South Carolina); Western Sahara
|FAO Marine Fishing Areas:||
Atlantic – eastern central; Atlantic – northeast; Atlantic – southwest; Atlantic – western central; Indian Ocean – eastern; Indian Ocean – western; Mediterranean and Black Sea; Pacific – eastern central; Pacific – northwest; Pacific – southwest
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||A fragmented population and relatively few occurrences suggest that this species may be naturally rare. Regional interrelationships between Mediterranean O. ferox and those from other parts of the open Atlantic Ocean (e.g. Azores, Canary Islands) are unknown. Given the cosmopolitan distribution of this species and its occurrence on both sides of the Straits of Gibraltar, the Mediterranean population cannot be considered disjunct based solely on analysis of records of capture. Genetic work is urgently required to assess this further. There have been unconfirmed, but reliable, reports by divers of small aggregations of O. ferox off the Transkei coast in South Africa. These sightings have been in depths of 20-30 m in areas of deepwater drop-offs (similar to those encountered off Lebanon), suggesting that this species may be more vulnerable to fishing pressure than previously assumed. Further investigation and monitoring of commercially caught small O. ferox in this region is required to assess if this is a nursery area. Large females observed off Beirut, apparently in the absence of any males, sometimes exhibit scars that might have been caused during courtship or mating.|
|Habitat and Ecology:||
Odontaspis ferox is a rarely encountered species that is morphologically very similar to Carcharias taurus, but larger and bulkier and mostly found in deeper water. It is an active-swimming offshore shark, caught and seen as individuals and in small groups (Compagno 2001). Odontaspis ferox lives on or closely associated with the bottom in or adjacent to deep waters along continental and insular shelves and upper slopes to depths to about 850 m (Fergusson et al. 2008). However, it is occasionally observed in very shallow water. For example, divers filmed underwater video of an individual in 20 m of water at the Cocos-Keeling Islands (B. Hutchins, pers. comm., cited in Fergusson et al. 2008). More recently, one capture and several diver observations and photographs of O. ferox in 12-30 m depth at Fernando de Noronha Archipeligo off eastern Brazil were reported by Garla and Garcia Jr. (2006). There are at least 15 records from pelagic zones in open waters of the Indian and Pacific Oceans, typically in areas proximal to deep-sea ridges and seamounts. Sightings have also recently been made in depths of about 30 m, on reefs adjacent to deep drop-offs in Lebanon and possibly off the Transkei coast in South Africa (Fergusson et al. 2008).
Little is known of the biology of this shark. Its reproduction may be similar to that of the sand tiger shark (C. taurus). Compagno (2001) cites an observation which suggests the species practices uterine cannibalism in the form of oophagy, resulting in the birth of single embryos from each uterus. The smallest recorded O. ferox is 107 cm total length (TL) which suggests a birth size between 100 and 110 cm TL (Fergusson et al. 2008), a size proportionally consistent with the size at birth for the smaller C. taurus (95-105 cm TL, Compagno 2001). O. ferox probably has a non-continuous breeding cycle similar to, or possibly more extended than, C. taurus. The gestation period for C. taurus is 9-12 months with a probable rest year between pregnancies (Compagno 2001).
There are insufficient data to precisely define the size at maturity for O. ferox. Males were estimated to mature between 200 and 250 cm and females between 300 and 350 cm total length (Fergusson et al. 2008) The maximum recorded size for females is 450 cm TL and 344 cm TL for males (Fergusson et al. 2008). An analysis of 64 O. ferox captures worldwide suggests an inverse relationship between shark size and depth, with small juveniles almost exclusively occurring in deepwater (>200m), although the relationship is not strongly defined (R2 = 0.129; p < 0.05; Fergusson et al. 2008). Mature sized O. ferox were caught across their whole depth range (15-850 m) but all small juveniles (<150 cm TL) came from depths greater than 200 m suggesting that parturition occurs in relatively deep water.
The large oily liver probably has a hydrostatic function (Last and Stevens 1994), and may help the shark to maintain neutral buoyancy while swimming. Stomachs examined have contained small bony fish, cephalopods, crustaceans (Last and Stevens 1994, Bass et al. 1975), and small squalid dogfish. A 188 cm female from near New Plymouth, New Zealand, had "the tip of the spine of a small ghost shark (Chimaeridae) impaled in its lower jaw cartilage" (Stewart 1997). A very large O. ferox trawled on the Norfolk Ridge north of New Zealand in 1997 was found to contain a 200 cm seal shark in its stomach. The above information suggests that this species is an opportunistic carnivore (Stewart 1997, cited in Pogonoski et al. 2002). Dentition suggests a more uniform diet of softer prey than in C. taurus (Compagno 2001). Stomachs were empty in specimens examined from the Gulf of Mexico (Bonfil 1995), Malta (A. Buttigieg, pers. comm.), the Azores (P.N. Duarte, pers. comm.), Canary Islands (A. Hernández, pers. comm.), and NSW (K. Graham data, N. Otway, pers. comm.). The only confirmed predator on adult O. ferox is the Cookie-cutter Shark (Isistius brasiliensis), based upon a relatively recent (March 2000) record of a female in the Canary Islands bearing a single fresh cookie-cutter bite to the gills (A. Hernández, pers. comm.).
|Use and Trade:||
This species is used for human consumption and for its very large, oily liver, which has reasonably high squalene content (Compagno 2001).
It also features in the aquarium trade.
Recent evidence of shallow water aggregations in a number of areas (Mediterranean Sea and Eastern Pacific Ocean) suggests that the species may be more vulnerable to fishing pressure than previously assumed, and potentially susceptible to coastal habitat impacts as well as to over-exploitation because of its presumed very low reproductive capacity. Although this species is not specifically targeted by commercial fishing activities, it likely has very low fecundity making it susceptible to local extirpation, even at seemingly small capture rates (Fergusson et al. 2008).
Since the 1970s there has been a substantial increase in deepwater fishing effort worldwide. In particular, significant trawl fisheries have developed on the continental slopes and ocean ridges off Australia, New Zealand and southern Africa, and the now-known depths at which O. ferox commonly lives (300-700 m) are regularly trawled. Similarly, as shallow water fisheries become depleted, fishing gear such as mesh-nets, droplines and longlines are being deployed at increasingly greater depths.
In the Mediterranean, dedicated efforts to detail captures and other indices of its abundance only began in the past ten years or so, and in particular since 1995. Regional literature and fisheries data concerning historical captures is essentially patchy and lacking in detail, so longer-term trends in its abundance are unknown. Moreover, fisheries records are sometimes confused by the widespread use of similar common names for different Mediterranean species; e.g., 'tiger' shark in Malta may refer to this species or indeed to the Shortfin Mako (Isurus oxyrinchus) or the Sandtiger Shark (Carcharias taurus). Occasionally O. ferox is caught by artisanal fisheries in the Tyrrhenian Sea off Calabria, Italy (M. Vacchi, pers. comm.). The species is uncommon in the Adriatic Sea but its current status there is difficult to assess, because of fishery misidentification with other sharks. Until the mid 1990s, occurrences off Croatia included relatively small (<200 cm TL) specimens caught by trawls and deepwater bottom longlines, which were locally confused with, and marketed as, smoothhound Mustelus spp. (Soldo and Jardas 2002). Since then there have been no more records of the species in the Adriatic (A. Soldo, pers. comm.).
Concern for the status of this shark in the Mediterranean is supported by records from New South Wales (NSW), Australia, where specimens of all sizes were caught by trawling on the upper slope. Survey and commercial catch data suggest that numbers of O. ferox on the NSW trawl grounds have markedly declined (by as much as 50%) since the advent of deepwater commercial trawling in the 1970s. In areas of steep un-trawlable terrain, characteristic of many locations in the Mediterranean Sea, gill-netting and longlining are likely to impact on local populations, with mature individuals being particularly vulnerable. Although O. ferox is not specifically targeted by commercial fishing activities in the Mediterranean and elsewhere, its likely very low fecundity make it susceptible to local extirpation, even at seemingly small capture rates.
Specimens are most often taken nocturnally by bottom gillnets, bottom longlines and vertical setlines operating over, or closely adjacent to, rocky or boulder-strewn seafloors. Trawler captures are likely in various areas (e.g., Sicilian Channel and Adriatic Sea). Anecdotal data from SCUBA divers in Beirut, who have encountered O. ferox at a nearshore reef over more than a decade, suggest an erratic decline in the number of sharks being encountered there despite regular diving at the same site each year. It is unclear if wars in Lebanon, which have some limited local impact on the marine environment (ships wrecked, etc.) are a factor. There has been no evidence of sharks being deliberately harassed or killed locally, other than a small number of incidental captures to artisanal fishermen in neighbouring waters.
In recent years, the discovery of at least one apparent aggregation ground for these sharks in the Mediterranean, off Lebanon (Fergusson et al. 2008) clearly indicates the vulnerability of these large, apparently harmless and rather sluggish sharks to human interference or directed fisheries. A particular concern must be degradation of favoured inshore habitats which may be used for reproduction during the summer months, as suspected with the Lebanese site.
Coastal development for tourism, coupled to uncontrolled spearfishing, unregulated coastal fisheries, pollution and increased human aquatic leisure activities may all seriously impact these sharks whilst inhabiting areas outside their deepwater environment, much as they may account for the contemporary acute decline or even disappearance of the (routinely coastal) sandtiger Carcharias taurus from its previous Mediterranean range (Fergusson et al. 2002).
Commercial fishing, whereby this species is taken incidentally, on the outer continental shelf and continental slope is a potential threat to its survival in south-eastern Australian waters.
From the available information, O. ferox was never abundant off New South Wales (NSW), but there is strong evidence that numbers seriously declined between 1972 and 1997. Of the 36 specimens caught by the NSW Fisheries Research Vessel Kapala, 33 were caught between 1975 and 1981 (from 500 slope trawl tows), but only three were taken from about 300 trawl tows made between 1982 and 1997 (Fergusson et al. 2008).
Comparable data are available for NSW upper slope trawl surveys in 1976-77 and 1996-97 where gear and sampling protocols were similar (see Graham et al. 1997). Twelve captures (14 sharks) were made during 246 tows in 1976-77, but only a single juvenile was caught during 165 tows made in 1996-97. Although considered in Pogonoski et al. (2002) as Near Threatened, based on available NSW catch data, reassessment to Vulnerable is warranted for Australia.
There has been limited take for aquarium display (e.g. Kelly Tarlton's Aquarium at Auckland NZ), but the maximum survival in captivity has been 11 months.
Small numbers were observed caught on longline gear at about ~300 m along the south KZN coast, South Africa, in the late 1980s, and further anecdotal information indicates relatively frequent capture of these sharks (of approx. 2 m TL) during target fishing for deep-sea sharks and rays (D. Ebert, pers. comm. 2004). Recent evidence of possible sightings of shallow water aggregations off the Transkei coast, South Africa, at depths of 20-30 m suggests that this species may be more vulnerable to fishing pressure than previously assumed.
Because the numbers of C. taurus along the NSW coast had been seriously depleted by indiscriminate spear fishing, and by some commercial harvesting, that species was protected in 1984 (Pollard et al. 1996). To avoid any misidentification or claims of confusion with O. ferox, both species were included on the NSW protected species list.
Despite this legal protection, compliance is difficult to enforce and carcasses of juvenile O. ferox are sometimes marketed simply as "shark". However, even if they or larger adults were returned to the sea intact, these sharks are unlikely to survive the trauma of trawl capture from deepwater. In a wider context, as exploitation of deepwater fishery resources increases worldwide, fishing mortality of such species such as O. ferox will increase and may put the survival of the species at risk.
The species is presently (2006) being considered for protection in New Zealand (C. Duffy, pers. comm.).
Although the distribution and status of the population in subequatorial Africa is unknown, the apparent rarity and vulnerability of O. ferox means that should any aggregation sites be found, stringent protection would be wise.
At present this species has not been protected from commercial fishing in any subequatorial African country, due to the fact that it has been observed so rarely and no records have been recorded from any commercial vessel.
There are no specific protection measures in place for the Mediterranean, despite its status there. The protection of favoured coastal habitats and more detailed monitoring of catches within Mediterranean fisheries should be priorities. Conservation of frequented sites as a dive tourism attraction could provide an incentive for local protection, as for well-known C. taurus habitats in Australia and South Africa.
This species has been reported by divers at the Cocos-Keeling Islands (Australia) and also other areas such as the Kermadec Islands (New Zealand), the Mediterranean, and Malpelo Island off Columbia. Such community-based dive observations or monitoring may be of use in obtaining information on its biology and knowledge of important habitats in shallow waters.
Further study is needed to accurately determine the distributional range, abundance and biology (including possible migrations, sex ratios, fecundity, etc.) of this species.
Any dead specimens landed by commercial fishing (especially trawling) operations should be retained and delivered to the nearest relevant research organisation, so that more biological information can be obtained.
There is now more evidence that coastal locations are frequented by mature O. ferox on a repetitive seasonal basis, possibly for reproduction. Where identified, these sites deserve stringent protection.
Development of by-catch mitigation measures such as trawl exclusion devices should be undertaken in relevant fisheries.
|Citation:||Pollard, D., Gordon, I., Williams, S., Flaherty, A., Fergusson, I.K., Dicken, M. & Graham, K. 2009. Odontaspis ferox. The IUCN Red List of Threatened Species. Version 2014.3. <www.iucnredlist.org>. Downloaded on 21 December 2014.|