99 research outputs found
Dipturus argentinensis, argentine skate
The Argentine Skate (Dipturus argentinensis) occurs in the Southwest Atlantic from central Chubut to southern Santa Cruz, Argentina and off the northwest Falkland Islands (Malvinas). It inhabits continental and insular shelves and slopes at depths of 85–400 m. Maximum size is unknown as only immature specimens have been caught (up to 125 cm total length) and there is some question as to where the adult population occurs. This skate is captured in commercial demersal trawl fisheries, which are intense across its entire known geographic and bathymetric range. It is captured in the target trawl fishery for skates off the Falkland Islands (Malvinas). Identification is an issue, and it may be captured more than is perceived. More information is needed to determine the level of overlap with fisheries and this species' catchability and sensitivity to fishing. Research is needed on distribution, life history, population size and trends, and threats. Since it is unknown whether fishing is causing a population reduction, there is currently inadequate information available to assess the Argentine Skate beyond Data Deficient.Fil: Pollom, R.. University Fraser Simon; CanadáFil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); ArgentinaFil: Cuevas, J. M.. Wildlife Conservation Society; Estados UnidosFil: Pompert, J.. Georgia Seafoods; PaÃses BajosFil: Herman, K.. Georgia Aquarium; Estados Unido
Discopyge castelloi, Castello's Apron Numbfish
Castello's Apron Numbfish (Discopyge castelloi) is a small (to at least 31 cm total length) ray that occurs in the Southwest Atlantic from Necochea, Buenos Aires, to Camarones, Chubut, Argentina. It inhabits the inner continental shelf at depths of 35–56 m. Its depth range suggests that it is exposed to commercial and artisanal demersal trawl fisheries. Commercial fishing began in Argentina in the late 1800s, became industrialized after World War II, and increased rapidly in the 1980s. By 1992 there were over 300 coastal trawlers. This number increased to over 400 in 2015, and the number of fishing trips undertaken by that fleet nearly doubled from over 7,600 to nearly 14,000 over that time frame. The overall number of fishing vessels in operation in Argentina has grown from under 300 in 1990 to nearly 1,000 in 2015. This species has however been caught only rarely, and may have either a low catchability or a depth range deeper than is currently known. Further research is needed on distribution, life history, population size and trend, and threats. Since it is unknown whether fishing is causing a population reduction, there is currently inadequate information available to assess Castello's Apron Numbfish beyond Data Deficient.Fil: Pollom, R.. University Fraser Simon; CanadáFil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); ArgentinaFil: Cuevas, J. M.. Wildlife Conservation Society; Estados UnidosFil: Herman, K.. Georgia Aquarium; Estados UnidosFil: Rincon, G.. Universidade Federal Do Maranhao.; Brasi
Malacoraja obscura, Brazilian Soft Skate
The Brazilian Soft Skate (Malacoraja obscura) is a small (to 68 cm total length) skate that has a very restricted range in the Southwest Atlantic Ocean from central EspÃrito Santo and northern Rio de Janeiro states in Brazil. It inhabits the continental slope at depths of 808-1,105 m. Although Extent of Occurrence cannot be calculated because the species is only known from two localities, it is suspected to be about 30,000 km2 (if the species is assumed to inhabit the steep slope between the two known localities). Area of Occupancy is estimated at 3,680 km2 (calculated based on including the known depth range of the species between the two known localities). This skate inhabits waters currently beyond the reach of fisheries, and there are no other known threats. Therefore, the population is suspected to be stable and the Brazilian Soft Skate is assessed as Least Concern.Fil: Pollom, R.. University Fraser Simon; CanadáFil: Charvet, P.. Universidade Federal do Paraná; BrasilFil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Herman, K.. Georgia Aquarium; Estados UnidosFil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; UruguayFil: Rincon, G.. Universidade Federal Do Maranhao.; Brasi
Sympterygia acuta, Bignose Fanskate
The Bignose Fanskate (Sympterygia acuta) is a small (to 62 cm total length) skate that occurs in the Southwest Atlantic from Rio de Janeiro, Brazil to BahÃa Blanca, Buenos Aires, Argentina. It inhabits the continental shelf from inshore to 188 m depth. It is captured in intense largely unmanaged demersal trawl fisheries throughout its geographic range. It is one of the most commercially important species and the wings are sold mainly to Asian markets at high prices. In southern Brazil, research trawl catchper-unit-effort revealed a decline in biomass of 74.5% between 1974 and 2005, equivalent to a population reduction of >83% scaled over three generations (40.5 years). This species is a target of the longline fishery in Uruguay, but now it is uncommonly captured in research trawl surveys there. Further, in Argentina, total skate landings have peaked and are declining as a result of overfishing. Overall, due to intense and largely managed trawl fisheries that operate throughout its geographic and depth range, it is suspected that the Bignose Fanskate has undergone a population reduction of >80% over the past three generations (40.5 years), and it is assessed as Critically Endangered A2bd.Fil: Pollom, R.. University Fraser Simon; CanadáFil: Barreto, R.. Centro Nacional Pesquisa E Conservação Da Biodiversidad; BrasilFil: Charvet, P.. Universidade Federal do Paraná; BrasilFil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); ArgentinaFil: Cuevas, J. M.. Wildlife Conservation Society; Estados UnidosFil: Herman, K.. Georgia Aquarium; Estados UnidosFil: Montealegre Quijano, S.. Universidade Federal de Sao Paulo; BrasilFil: Motta, F.. Universidade Federal de Sao Paulo; BrasilFil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Urugua
Atlantoraja cyclophora, Eyespot Skate
The Eyespot Skate (Atlantoraja cyclophora) is a small (to 74 cm total length) skate that occurs in the Southwest Atlantic from Rio de Janeiro, Brazil to San MatÃas Gulf, Argentina. It inhabits the continental shelf from inshore to 100 m depth, and occasionally to 320 m. It is captured in intensive and largely unmanaged demersal trawl fisheries which operate throughout its geographic and depth range. In southern Brazil there are no time-series of abundance, but fisheries there are intense and it is suspected that they are leading to population reduction. In Uruguay, research trawl catch-per-uniteffort of this species declined 82% from 1,910 kg/hr in 2004–2013 to 343 kg/hr from 2013 to 2017, equivalent to a >95% population reduction scaled over three generations (40.5 years). In the Rio del Plata Estuary, the landings of coastal rays including this species was low until the mid-1990s, but increased retention led to substantial increases in landings which peaked in 2008, followed by a decline. In Argentina, reported landings of skates in general increased from 900 t in 1993 to a peak of 28,000 t in 2007, and then declined to 24,000 t in 2009–2010. Overall, due to intense and increasing fishing pressure across its range, decreasing abundance, and its relatively slow life history, it is suspected that the Eyespot Skate has undergone a population reduction of 50–79% over the past three generations (40.5 years), and it is assessed as Endangered A2bd.Fil: Pollom, R.. University Fraser Simon; CanadáFil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; BrasilFil: Charvet, P.. Universidade Federal do Paraná; BrasilFil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); ArgentinaFil: Cuevas, J. M.. Wildlife Conservation Society; Estados UnidosFil: Faria, V.. Universidade Federal Do Ceara; BrasilFil: Montealegre Quijano, S.. Universidade Federal de Sao Paulo; BrasilFil: Motta, F.. Universidade Federal de Sao Paulo; BrasilFil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Urugua
Dipturus leptocaudus, Thintail Skate
The Thintail Skate (Dipturus leptocaudus) is a medium-sized (to 88 cm total length) skate that occurs in the Southwest Atlantic from Santa Catarina, Brazil to Uruguay (and possibly Argentina). It inhabits the continental shelf and upper slope at depths of 10–550 m. It is captured in commercial deep-water trawl, longline, and gillnet fisheries, which operate throughout its known range. Little information is available regarding the amount of catches due to identification issues. Dipturus spp. were the most abundant elasmobranchs caught in the monkfish (Lophius gastrophysus) deep-water gillnet fishery off southern Brazil, which intensified in the 2000s. These industrial gillnet fisheries often also target skates, and have led to declines in other ecologically similar species such as angel sharks (Squatina spp.). Dipturus spp. were shown to be highly vulnerable to such fisheries in a productivity-susceptibility analysis. There are also deep-water trawlers operating in the area targeting shrimp and squid, which are intense. Overall, due to the presence of intense and inadequately managed trawl fisheries that operate throughout its range, it is suspected that the Thintail Skate has undergone a population reduction of 30–49% over the past three generations (21 years), and it is assessed as Vulnerable A2d.Fil: Pollom, R.. University Fraser Simon; CanadáFil: Charvet, P.. Universidade Federal do Paraná; BrasilFil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); ArgentinaFil: Cuevas, J. M.. Wildlife Conservation Society; Estados UnidosFil: Herman, K.. Georgia Aquarium; Estados UnidosFil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; UruguayFil: Pompert, J.. Georgia Seafoods; PaÃses BajosFil: Rincon, G.. Universidade Federal Do Maranhao.; Brasi
Bathyraja scaphiops, Cuphead Skate
The Cuphead Skate (Bathyraja scaphiops) is a medium-sized (to 117 cm total length) skate that occurs in the Southwest Atlantic from off Rio Grande do Sul, Brazil to Tierra del Fuego, Argentina and the Falkland Islands (Malvinas). It inhabits continental and insular shelves and slopes at depths of 30?925 m. It is targeted or captured as utilized bycatch in demersal trawl fisheries, including the southern Brazil otter trawl fishery, the Patagonian scallop and hake fisheries, and the Falkland Islands (Malvinas) targeted multi-species skate fishery. At the northern extent of its range in southern Brazil, it is captured in the otter trawl fishery which is intense; reductions in the population are suspected there but there are no data. In the Argentina-Uruguay Common Fishing Zone (AUCFZ), this species was captured frequently in commercial trawls between 1984 and 2009. On the shelf edge off Argentina between Buenos Aires and northern Santa Cruz, this species was present in 9% of research trawls in the area trawled by the Patagonian scallop fishery in 2010. In the Falkland Islands (Malvinas), this species made up an average of 3.5% of the catch in the multi-species skate fishery between 1993 and 2013, with no clear trend in catch-per-unit-effort over that time frame. Overall, although this species is subjected to substantial fishing pressure, it has remained common in catches and it may have refuge over rough substrates that are untrawlable. Although fisheries are likely leading to some reduction in population size, the level is not suspected to approach the thresholds for a threatened assessment. Therefore, the Cuphead Skate is assessed as Least Concern.Fil: Pollom, R.. University Fraser Simon; CanadáFil: Charvet, P.. Universidade Federal do Paraná; BrasilFil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); ArgentinaFil: Cuevas, J.M.. Wildlife Conservation Society; Estados UnidosFil: Herman, K.. Georgia Aquarium; Estados UnidosFil: Paesch, L.. Direccion Nacional de Recursos Acuaticos ; UruguayFil: Pompert, J.. No especifÃca;Fil: Rincon, G.. Universidade Federal Do Maranhao.; Brasi
Amblyraja georgiana, Antarctic Starry Skate
The Antarctic Starry Skate (Amblyraja georgiana) is a medium-sized (to 115 cm total length) deepwater skate that occurs in the Southeast Pacific Ocean off southern Chile, in the Southwest Atlantic Ocean off southern Argentina and the Falkland Islands (Malvinas), in the Atlantic and Pacific Antarctic Oceans from South Georgia Island and the Antarctic Peninsula to the Ross Sea, and in the Indian Antarctic off the Crozet Islands. It is demersal on continental and insular slopes at depths of 20?1,255 m, and is captured as bycatch in trawl and longline fisheries, particularly those targeting Patagonian Toothfish (Dissostichus eleginoides). There are no population size estimates for this skate, and it is not clear what the current population trend is. Although estimates of bycatch around South Georgia and the Ross Sea are comprised of a low percentage of overall estimated stock biomass, the demographic consequences are unknown and require further research. Furthermore, catch levels in other areas are unknown, and some specimens previously referred to as this species may include cryptic individuals of a yet-to-be-described species. Overall, it is not clear what level of fishing mortality this species is exposed to across its range, and further research is needed on distribution, population size and trend, and threats. Therefore, the Antarctic Starry Skate is assessed as Data Deficient.Fil: Pollom, R.. University Fraser Simon; CanadáFil: Acuña, E.. Universidad Católica del Norte; ChileFil: Bustamante, C.. Universidad de Antofagasta; ChileFil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); ArgentinaFil: Cuevas, J.M.. Wildlife Conservation Society; Estados UnidosFil: Herman, K.. Georgia Aquarium; Estados UnidosFil: Pompert, J.. No especifÃca;Fil: Velez Zuazo, X.. No especifÃca
Atlantoraja castelnaui, Spotback Skate
The Spotback Skate (Atlantoraja castelnaui) is a medium-sized (to 147 cm total length) skate that occurs in the Southwest Atlantic from Rio de Janeiro, Brazil, to Buenos Aires, Argentina. It inhabits the continental shelf and upper slope from inshore to 300 m depth. It is captured in intense and largely unmanaged demersal trawl fisheries throughout its geographic range. Two lines of evidence indicate a population reduction. First, in Santa Catarina State, Brazil, catch-per-unit-effort (CPUE) declined by an estimated 54% between 1974 and 1981. Second, a 75% decline in CPUE was estimated from 1994 to 1999 in Rio Grande do Sul, Brazil. Both declines are consistent with a population reduction of >99% over three generation lengths (48 years). This large skate has a slow life history, and many skates with similar characteristics have undergone severe population reductions and face increased extinction risk. It is highly susceptible to exploitation and does not have any refuge from fishing at depth. Overall, due to declining abundance from intense and largely unmanaged fishing through most of its range combined with its large size and presumed late age-at-maturity (and therefore high sensitivity to fishing pressure), it is suspected that the Spotback Skate has undergone a population reduction of >80% over the past three generation lengths (48 years), and it is assessed as Critically Endangered A2bd.Fil: Pollom, R.. University Fraser Simon; CanadáFil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; BrasilFil: Charvet, P.. Universidade Federal do Paraná; BrasilFil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); ArgentinaFil: Cuevas, J. M.. Wildlife Conservation Society; Estados UnidosFil: Faria, V.. Universidade Federal Do Ceara; BrasilFil: Herman, K.. Georgia Aquarium; Estados UnidosFil: Motta, F.. Universidade Federal de Sao Paulo; BrasilFil: Paesch, L.. Direccion Nacional de Recursos Acuaticos ; UruguayFil: Rincon, G.. Universidade Federal Do Maranhao.; Brasi
Psammobatis bergi, Blotched Sandskate
The Blotched Sandskate (Psammobatis bergi) is a small (to 61 cm total length) skate that occurs in the Southwest Atlantic from Rio de Janeiro, Brazil to the northern San Jorge Gulf, Chubut, Argentina. It inhabits the inner continental shelf at depths of 10-80 m. It is caught in demersal trawl fisheries, which are intense in parts of its range. It is typically discarded dead where caught. Its continued common presence in trawls and its small size suggest that it may have a productive enough life history to withstand fishing pressure and the population is suspected to be stable. Therefore, the Blotched Sandskate is assessed as Least Concern.Fil: Pollom, R.. University Fraser Simon; CanadáFil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; BrasilFil: Charvet, P.. Universidade Federal do Paraná; BrasilFil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); ArgentinaFil: Cuevas, J. M.. Wildlife Conservation Society; Estados UnidosFil: Herman, K.. Georgia Aquarium; Estados UnidosFil: Montealegre Quijano, S.. Universidade Federal de Sao Paulo; BrasilFil: Motta, F.. Universidade Federal de Sao Paulo; BrasilFil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; UruguayFil: Rincon, G.. Universidade Federal Do Maranhao.; Brasi
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