Species: Dasyatis pastinaca Justification




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Species: Dasyatis pastinaca

Justification:

This stingray occurs in the eastern Atlantic and Mediterranean Sea. It occurs from the shore to about 200 m depth, but is more commonly found in shallow waters (<50 m). This depth distribution makes it more vulnerable to small-scale inshore fisheries than to offshore trawling. For example, Dasyatis pastinaca made up more than 40% of the elasmobranch biomass captured in the trammel net fishery off the Balearic Islands (Morey et al., In Review). In the northeast Atlantic, it is a less common species, generally showing a low abundance index in comparison to the Mediterranean Sea and may have disappeared from the south of the Bay of Biscay. Data from comparative trawl surveys (1948 and 1998) conducted in the Adriatic Sea suggest that this species may have decreased in abundance. Although few data are available, this species appears to be less common than it once was in the Mediterranean and Northeast Atlantic. It is currently assessed as Near Threatened there and further investigation is required into catches and the taxonomic status of population throughout this species? global distribution before it can be assessed beyond Data Deficient globally.



Geographic Range

Eastern Atlantic: from southern Norway and the UK to South Africa, including the Canary Islands, Madeira, western Baltic Sea, Mediterranean Sea, Black Sea and Sea of Marmara (Bilecenoglu et al. 2002, Serena 2005). In Celtic Seas this species is regarded as a vagrant from more southern waters (ICES 2005a). The few observations of this species in the North Sea are restricted to Shetland waters and the southern North Sea, where they are occasionally caught in inshore surveys (ICES 2005b). This ray has a higher presence in the western-central Mediterranean area (coasts of Morocco, Spain, France, Tyrrhenian, Corsica, Sardinia and Sicily) than elsewhere in the Mediterranean region (Baino et al. 2001).



Population

Mediterranean

There is no information on the size of the population of this species within the Mediterranean, however the Mediterranean International Trawl Surveys (MEDITS) from 1994?1999 revealed a low frequency of occurrence for D. pastinaca. It appeared in 49 hauls, which was only 0.5% of the total number of hauls, but these surveys only sampled depths from 50?800 m and this species is more common in shallow waters <50 m depth. Comparative trawl surveys conducted in 1948 (Hvar) and 1998 (MEDITS) in the Adriatic Sea (both up to 400 m depth) suggest that the abundance of D. pastinaca may have decreased during this period. The frequency of occurrence (frequency log transformed data) of D. pastinaca on the shelf according to the 1948 survey was ~0.5, whereas frequency of occurrence on the shelf in the 1998 survey was <0.1 (Jukic-Peladic et al. 2001).

Ferreti et al (2013) report 1.13 fold increase of D. pastinaca in Adriatic Sea.

Northeast Atlantic

In the Northeast Atlantic the common stingray is clearly less abundant than in the Mediterranean. D. pastinaca has reportedly disappeared from the Bay of Biscay (Quero1998), as observed for other demersal elasmobranch species. The average catch rate for this species caught during the quarter 1 IBTS in the North Sea, Skagerrak and Kattegat is 0.0006 (number per hour, 1977?2004) (ICES 2005b). Within UK groundfish surveys, Dasyatis pastinaca was only recorded occasionally in the western English Channel at depths of 17?160 m (Ellis et al. 2005).



Trend

Unknown


Habitat and Ecology

Dasyatis pastinaca is a demersal brackish to marine water species, found over sandy and muddy bottoms from shallow waters to a depth of approximately 200 m (Whitehead et al. 1984), although it seems to be most abundant in inshore waters. Bottom trawl surveys in the Mediterranean Sea suggest that it is more common in waters <50 m depth (Morey et al. In review, Massuti and Moranta 2003, Relini et al. 2000). This species can sometimes inhabit areas close to estuaries and over rocky reefs. Depth distribution of the biomass index shows values of 1¬?10 kg/km² between depths of 0?100 m, and 0.1?1 kg/km² at depths of 100?200 m (Baino et al. 2001).

D. pastinaca reaches a maximum reported size of 140 cm disc width (DW) and 250 cm total length (TL) (Bauchot 1987, Fisher et al. 1987, Notarbartolo and Bianchi 1998). The size at maturity of females is estimated at about 38 cm DW (Capape et al. 1996) and 60 cm TL/28 cm DW (Ismen 2003). Males mature at a smaller size, estimates ranging from 32 cm DW (Capape et al. 1996) and 50 cm TL/26 cm DW (Ismen 2003). The age at maturity and longevity of this species is unknown.

Females reproduce twice a year (Notarbartolo and Bianchi 1998), however the reproductive age and period of gestation is unknown. In the northern Adriatic, reproduction takes place between September and May, during which pregnant females approach the coast. Bini (1967) reported that pupping occurred between July and August, and 4?9 pups/litter are produced (Notarbartolo and Bianchi 1998). Several localities where the species aggregates during mid June and July are known in the Balearic Islands. These aggregations of mature stingrays are probably related to reproduction (Morey et al. in review.). Young specimens are common in shallow waters over sandy bottoms, and parturition was reported to occur in early July in the eastern Mediterranean (Ismen 2003). Neonates are approximately 20 cm TL (8 cm DW) (Ismen 2003). The rate of population increase and natural mortality are unknown.



D. pastinaca feed mainly on demersal and benthic animals, such as crustaceans, cephalopods, clams, polychaetes and fish (Notarbartolo and Bianchi 1998, Whitehead et al. 1984). In a study by Ismen (2003), crustaceans represented more than 99% of the diet when pooling all size classes, but teleost fish were of increasing importance in the diet of larger stingrays.

Threats

This species is taken as bycatch and is sometimes targeted in semi-industrial, small-scale and commercial bottom trawl, gillnet, beach seine, bottom longline and trammelnet fisheries. Commercial fishermen often cut off the tails of stingrays following capture and prior to discarding, although it is unclear as to how this affects discard survival (Notarbartolo and Bianchi 1998). Little data are available on catches as a result of discarding at sea. The species? preference for shallow waters (<50 m) makes it more vulnerable to small-scale inshore fisheries than to offshore trawling. For example, D. pastinaca made up more than 40% of the elasmobranch biomass captured in the trammel net fishery off the Balearic Islands (Morey et al. in review.). Small scale fisheries operating within this species? shallow water range in the Mediterranean Sea and Atlantic make up an important component of the European fishing fleet (Stergiou et al. 2006). This species was not recorded in recent (1999-2000) experimental fishing trials with trammel nets conducted within several parts of this species? known range in the Mediterranean and northeast Atlantic (Stergiou et al. 2006). There is a ban on trawling within 3 nm of the coast for EU countries, however there are some exceptions to this, and both legal and illegal trawling continues to occur in shallow waters in parts of the northern Mediterranean Sea.

Important grounds for reproduction (mating, parturition, nursery areas) seem to be associated with shallow sandy bottoms, which human disturbance (e.g. tourism activities on beaches) or fishing pressure (trammel and gillnets targeting cuttlefish, mullets, bass and flatfishes, and trawling) impact.

Conservation Actions

D. pastinaca is protected within five of the six existing Balearic Island marine reserves. Although artisanal fishing is allowed within these marine protected areas (MPAs), these stingrays must be released alive if caught. Accurate monitoring of artisanal catch in those areas where the species is very commonly taken is needed to provide information on the size of the population.

Regulation (EU) No 605/2013 of the European parliament, amending European Commission Regulation No. 1185/2003, advises, “that all elasmobranch species should be landed with their fins/wings naturally attached to their bodies.”



Bibliography

Baino, R., Serena, F., Ragonese, S., Rey, J. and Rinelli P. 2001. Catch composition and abundance of Elasmobranchs based on the MEDITS program. Rapp. Comm. int. Mer Mèdit 36: 234.

Bilecenoglu, M., Taskavak, E., Mater S. and Kaya, M. 2002. Checklist of the marine fishes of Turkey. Zootaxa 113: 1-194.

Bini G. 1967. Atlante dei pesci delle coste italiane: Leptocardi, Ciclostomi, Selaci. Mondo Sommerso, Milan.

Capapé, C., Diop, M., N?dao, M. and Ben Brahim, R. 1996. Observations biologiques comparees entre quelques especes de selaciens des cotes Tunisiennes (Mediterranee centrale) et de la region de dakar-ouakam (Senegal, Atlantique oriental tropical). Ichtyophysiologica Acta 19: 179-199.

Coelho, R., Erzini, K., Bentes, L., Correia, C., Lino, P.G., Monteiro, P., Ribeiro, J. and Gonálves, J.M.S. 2005. Semi pelagic longline and trammel net elasmobranch catches in the Algarve (southern Portugal): catch composition, catch rates and discards. Journal of Northwest Atlantic Fisheries Science 35: 531?537.

Ellis, J.R., Cruz-Martinez, A., Rackham, B.D. and Rogers, S.I. 2005. The distribution of chondrichthyan fishes around the British Isles and implications for conservation. Journal of Northwest Atlantic Fisheries Science 35: 195-213.

Ferretti, F., Osio, G. C., Jenkins, C. J., Rosenberg, A. A., & Lotze, H. K. (2013). Long-term change in a meso-predator community in response to prolonged and heterogeneous human impact. Scientific reports, 3.

Fischer, W., Bauchot, M.-L. and Schneider, M. 1987. Fiches FAO d'identification des espèces pour les besoins de la pêche. Méditerranée et mer Noire. Zone de Pêche 37. FAO, Rome, Italy.

ICES (International Council for the Exploration of the Sea). 2005. North Sea Elasmobranchs: distribution, abundance and biodiversity. Theme Session on Elasmobranch Fisheries Science.

ICES (International Council for the Exploration of the Sea). 2005. Report of the Working Group on Elasmobranch Fishes (WGEF). ICES Advisory Committee on fishery Management, 14-21st June 2005, Lisbon, Portugal.

Ismen, A. 2003. Age, growth, reproduction and food of common stingray (Dasyatis pastinaca L., 1758) in Iskenderun Bay, the eastern Mediterranean. Fisheries Research 60:: 169-176.

Ismen, A. (2003). Age, growth, reproduction and food of common stingray (Dasyatis pastinaca L., 1758) in İskenderun Bay, the eastern Mediterranean. Fisheries Research, 60(1), 169-176.

IUCN. 2009. IUCN Red List of Threatened Species (ver. 2009.2). Available at: www.iucnredlist.org. (Accessed: 3 November 2009).

Massuti, E. and Moranta, J. 2003. Demersal assemblages and depth distribution of elasmobranchs from the continental shelf and slope off the Balearic Islands (western Mediterranean). ICES Journal of Marine Science 60: 753-766.

Morey, G, Moranta, J, Riera, F., Grau, A.M. and Morales-Nin, B. 2006. Elasmobranchs in trammel net fishery associated to marine reserves in the Balearic Islands (NW Mediterranean). Cybium 30: 125-32.

Notarbartolo di Sciara, G. and Bianchi, I. 1998. Guida degli squali e delle razze del Mediterraneo. Muzzio, Padova.

Relini G., Biagi F., Serena F., Belluscio A., Spedicato M.T., Rinelli P., Follesa M.C., Piccinetti C., Ungaro N., Sion L. and Levi D. 2000. I selaci pescati con lo strascico nei mari italiani. Biologia Marina Mediterranea 7(1): 347-384.



Serena F. 2005. Field identification guide to the sharks and rays of the Mediterranean and Black Sea. FAO, Rome.

Tortonese, E. 1956. Fauna d?Italia: Leptocardia, Ciclostomata, Selachii. Calderini, Bologna.


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