Search

The Lesser Numbfish (Narcine brasiliensis) is a small (to 45 cm total length) ray that occurs in the Southwest Atlantic from southern Brazil to Buenos Aires Province, Argentina. It is benthic on soft substrates of the continental shelf at depths of 6?60 m. It is captured in intense and largely unmanaged commercial and artisanal trawl and beach seine fisheries throughout much of its geographic range. A population reduction is suspected from the peak and subsequent declines in reported ray landings from the Rio del Plata area. This species is discarded when caught and discard survival rates are unknown, but are suspected to be variable based on the injuries of captured individuals. Although this ray is subject to high fishing pressure across its range, it is still observed commonly in fisheries despite this pressure. It is suspected that the Lesser Numbfish has undergone a population reduction of 20-29% over the past three generations (26 years), and it is assessed as Near Threatened (nearly meeting Vulnerable A2d). Fil: Pollom, R.. University Fraser Simon; Canadá Fil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Faria, V.. Universidade Federal Do Ceara; Brasil Fil: Herman, K.. Georgia Aquarium; Estados Unidos Fil: Marcante, F.. Universidade Federal Do Rio Grande.; Brasil Fil: Montealegre Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Uruguay Fil: Rincon, G.. Universidade Federal Do Maranhao.; Brasil

The Brazilian Guitarfish (Pseudobatos horkelii) is a small (to 138 cm total length) shark-like ray that occurs in the Southwest Atlantic from Rio de Janeiro, Brazil, to northern Argentina. It is demersal on soft substrates of the continental shelf inshore to 150 m depth. It is captured in intense and largely unmanaged commercial and artisanal demersal trawl, gillnet, longline, and beach seine fisheries throughout its geographic range. There are three estimates of population reduction. First, in Rio Grande do Sul, total landings increased from 842 t in 1975 to 1,804 t in 1984 and then declined continuously to 157 t in 2001, the equivalent of a >99% reduction over three generations (55.5 years). Second, the average research trawl catch-per-unit-effort of Brazilian Guitarfish in southern Brazil over the years 1993 to 1999 was 17% of that observed during 1975 to 1986, also the equivalent of a >99% reduction over three generations. Fisheries remain intense and unmanaged there. Third, in Uruguay, this guitarfish is captured frequently in gillnets and longlines, is landed, and is sometimes targeted, and it is also captured in artisanal trawl fisheries. Catches from research trawls there in the 1980s and early 1990s were on average around 1,400 kg/hr, and between 2013 and 2017 were only 480 kg/hr, the equivalent of a >92% reduction over three generations. In Argentina, it is suspected that intense and inadequately managed gillnet fishing pressure has led to declines in abundance there as well. Overall, due to intense and inadequately managed fishing pressure throughout its range, and steep population declines, it is inferred that the Brazilian Guitarfish has undergone a population reduction of >80% over the past three generations (55.5 years), and it is assessed as Critically Endangered A2bd. Fil: Pollom, R.. University Fraser Simon; Canadá Fil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Herman, K.. Georgia Aquarium; Estados Unidos Fil: Martins, M. F.. Universidade Federal Do Rio Grande.; Brasil Fil: Montealegre Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Uruguay Fil: Rincon, G.. Universidade Federal Do Maranhao.; Brasil

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 Bahía 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; Canadá Fil: Barreto, R.. Centro Nacional Pesquisa E Conservação Da Biodiversidad; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Herman, K.. Georgia Aquarium; Estados Unidos Fil: Montealegre Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Uruguay

The Shortnose Guitarfish (Zapteryx brevirostris) is a small (to 66 cm total length) benthic shark-like ray that occurs in the Southwest Atlantic from Espírito Santo state, Brazil to Buenos Aires, Argentina. It inhabits inshore waters over soft substrates at depths of 2–140 m. It is captured in intense and largely unmanaged artisanal and commercial demersal trawl and gillnet fisheries throughout its geographic range. There are two estimates of population reduction. First, in Santa Catarina state, Brazil, catch-perunit-effort (CPUE) decreased 90% from 100 kg/hr in the 1980s to 10 kg/hr in 2005, the equivalent of a population reduction of >85% over three generation lengths (21 years). Second, in Uruguay, the research trawl survey CPUE declined by nearly 40%; in the 1980s and early 1990s, 2,200 kg/hr were caught, and between 2013 and 2017 there were just over 1,400 kg/hr caught, the equivalent of a population reduction of >25% over three generation lengths (21 years). Furthermore, demographic analyses have shown that this species is being overfished given the level of mortality it is exposed to. This guitarfish is subjected to intense and mostly unmanaged fishing pressure across its limited range, it has no refuge at depth, and where recorded in landings it has declined. Overall, it is suspected that the Shortnose Guitarfish has undergone a population reduction of 50–79% over the past three generation lengths (21 years), and it is assessed as Endangered A2bd. Fil: Pollom, R.. University Fraser Simon; Canadá Fil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Faria, V.. Universidade Federal Do Ceara; Brasil Fil: Herman, K.. Georgia Aquarium; Estados Unidos Fil: Marcante, F.. Universidade Federal Do Rio Grande.; Brasil Fil: Montealegre Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Uruguay Fil: Rincon, G.. Universidade Federal Do Maranhao.; Brasil

The Onefin Skate (Gurgesiella dorsalifera) is a small (to 53 cm total length) skate that occurs in the Southwest Atlantic from Rio de Janeiro to Santa Catarina State, Brazil. It is demersal on the continental slope at depths of 400–800 m. It is captured in deep-water demersal trawl fisheries, which were developed in Brazil in order to take some pressure off depleted inshore stocks. In southern Brazil, the trawl fishery began in the 1960s and entered a period of rapid expansion in the 1990s and 2000s, resulting in over 650 vessels fishing at depths of 20–1,000 m. From 2003 to 2007, this species was the second-most common discarded bycatch in southern Brazil shrimp trawls by the Spanish deep-water fleet (which comprised 68% of all deep-water trawls off Brazil during that time). This skate is also a common bycatch of the Argentine Squid fishery, which is intense and operates down to about 600 m depth. Although typically discarded, post-release mortality is suspected to be high and it is likely that fishing mortality is leading to a reduction in the population size. Overall, it is suspected that the Onefin 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; Canadá Fil: Barreto, R.. No especifíca; Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Faria, V.. Universidade Federal Do Ceara; Brasil Fil: Herman, K.. Georgia Aquarium; Estados Unidos Fil: Montealegre-Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Uruguay Fil: Rincon, G.. Universidade Federal Do Maranhao.; Brasil

The Spade Sandskate (Psammobatis rutrum) is a small (to 32 cm total length) skate that occurs in the Southwest Atlantic from Rio de Janeiro, Brazil to the San Matías Gulf, northern Chubut, Argentina. It inhabits the continental shelf at depths of 31–150 m. It is captured in demersal trawl fisheries, which are intense in parts of its range. There are no estimates of population trend for this species, but it is still caught commonly in fisheries despite a long history of fishing pressure, and therefore the population size is suspected to be stable. Its small size indicates that it likely has an early age-at-maturity and a fast growth rate and thus some ability to withstand fishing pressure. Therefore, the Spade Sandskate is assessed as Least Concern. Fil: Pollom, R.. University Fraser Simon; Canadá Fil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Faria, V.. Universidade Federal Do Ceara; Brasil Fil: Herman, K.. Georgia Aquarium; Estados Unidos Fil: Montealegre Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. No especifíca; Fil: Rincon, G.. Universidade Federal Do Maranhao.; Brasil

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; Canadá Fil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Herman, K.. Georgia Aquarium; Estados Unidos Fil: Montealegre Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Uruguay Fil: Rincon, G.. Universidade Federal Do Maranhao.; Brasil

The Groovebelly Stingray (Dasyatis hypostigma) is a medium-sized (to 58 cm disc width) ray that occurs in the Southwest Atlantic from Espírito Santo, Brazil to southern Buenos Aires Province, Argentina. It inhabits estuaries and the inner continental shelf at depths of 5–80 m. This stingray is highly valued and the meat is sold locally. It is captured in intense and largely unmanaged artisanal and commercial demersal trawl and gillnet fisheries that operate throughout its geographic range. This species is also likely to be affected by coastal habitat degradation and conversion around large cities. In Buenos Aires Province, it declined in research trawl landings by more than 86% between 1981 and 2006, equivalent to a population reduction of >88% over three generations. Fisheries are intense in the Brazilian portion of its range and similar reductions are suspected there. The level of management in place in the ArgentinaUruguay Common Fishing Zone may have prevented such a steep trajectory there. Overall, due to the presence of intense and mostly unmanaged fishing pressure across its range, at least one decline in an index of abundance, and a decline in habitat quality, balanced with a suspected better situation in the Argentina-Uruguay Common Fishing Zone, it is suspected that the Groovebelly Stingray has undergone a population reduction of 50–79% over the past three generation lengths (27 years), and it is assessed as Endangered A2bcd. Fil: Pollom, R.. University Fraser Simon; Canadá Fil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Faria, V.. Universidade Federal Do Ceara; Brasil Fil: Herman, K.. Georgia Aquarium; Estados Unidos Fil: Montealegre Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Uruguay Fil: Rincon, G.. Universidade Federal Do Maranhao.; Brasil

The Argentine Torpedo (Tetronarce puelcha) is a medium-sized (to 120 cm total length) ray that occurs in the Southwest Atlantic from Espírito Santo, Brazil to San Jorge Gulf, Argentina. It is benthic on the continental shelf and slope at depths of 10–600 m, and also inhabits coastal lagoons. It is captured in intense and largely unmanaged commercial and artisanal demersal trawl and gillnet fisheries, which operate throughout most of its geographic range. Individuals that are caught are typically discarded at sea, but levels of post-release mortality are unknown. On the southern Brazilian shelf, this species declined by 97% in research trawl catch-per-unit-effort (CPUE) from 340 kg/hr in the 1980s to 10 kg/hr in 2005, equivalent to a >99% reduction over three generations. There are few data from Uruguay and Argentina, but this ray is rarely caught and may have undergone a similar decline there. Overall, due to the level of intense and inadequately managed fisheries throughout most of its range, its suspected unproductive life history, and significant estimated declines in CPUE in some areas, it is suspected that the Argentine Torpedo has undergone a population reduction of >80% over the past three generations (37.5 years), and it is assessed as Critically Endangered A2bd. Fil: Pollom, R.. University Fraser Simon; Canadá Fil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Herman, K.. Georgia Aquarium; Estados Unidos Fil: Montealegre-Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Uruguay Fil: Rincon, G.. Universidade Federal Do Maranhao.; Brasil

The Striped Smoothhound (Mustelus fasciatus) is a medium-sized (to 177 cm total length) shark that occurs in the Southwest Atlantic from Santa Catarina, Brazil, to southern Buenos Aires Province, Argentina. It is demersal on the continental shelf and upper slope, from inshore to 500 m depth. It is captured in intense and largely unmanaged commercial and artisanal demersal trawl, gillnet, and beach seine fisheries throughout its range. There are two population reduction estimates from research trawl surveys: (1) the southern Brazilian shelf; and, (2) the Argentina-Uruguay Common Fishing Zone. First, on the southern Brazilian shelf, catches of adults in research trawl surveys declined by 95% between 1981 and 2005, equivalent to a >99% population reduction over three generation lengths (43.5 years). Second, in the coastal region of the Bonaerensean District of northern Argentina and Uruguay, the biomass of this shark in trawl surveys decreased by 96% between 1994 and 1999, also equivalent to a >99% reduction over three generations. Due to the level of intense and largely unmanaged fishing pressure across its range, combined with its relatively unproductive life history, and noted declines, it is suspected that the Striped Smoothhound has undergone a population reduction of >80% over the past three generations (43.5 years), and it is assessed as Critically Endangered A2bd. Fil: Pollom, R.. University Fraser Simon; Canadá Fil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Herman, K.. Georgia Aquarium; Estados Unidos Fil: Montealegre Quijano, S.. Universidade Federal Do Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Uruguay Fil: Rincon, G.. Universidade Federal Do Maranhao.; Brasil

The La Plata Skate (Atlantoraja platana) is a medium-sized (to 91 cm total length) skate that occurs in the Southwest Atlantic from Espírito Santo, Brazil to Chubut, Argentina. It inhabits clay, mud, and sand substrates on the continental shelf and upper slope from inshore to 320 m depth. This skate is captured in intensive and largely unmanaged demersal trawl fisheries throughout its range. In southern Brazil, this skate is subjected to intense industrial and artisanal fishing pressure and it is suspected that this has led to declines in abundance there. 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. It is smaller-bodied than the Critically Endangered congeneric Spotback Skate (Atlantoraja castelnaui), and by comparison is suspected to be less sensitive to fishing pressure. Although it is still common in catches, the combination of widespread intensive fishing pressure across its range, inadequate management measures, its high catchability, and declines in reported overall skate catches, it is suspected that the La Plata 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; Canadá Fil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Faria, V.. Universidade Federal Do Ceara; Brasil Fil: Montealegre-Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos ; Uruguay Fil: Rincon, G.. Universidade Federal Do Maranhao.; Brasil

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 Matías 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; Canadá Fil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Faria, V.. Universidade Federal Do Ceara; Brasil Fil: Montealegre Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Uruguay

The Narrownose Smoothhound (Mustelus schmitti) is a small (to 109 cm total length) shark that occurs in the Southwest Atlantic from Rio de Janeiro, Brazil to south of Puerto Deseado, Santa Cruz, Argentina. It inhabits the continental shelf and estuaries at depths of 2–195 m. It is captured in intense and largely unregulated commercial and artisanal demersal trawl, gillnet, and beach seine fisheries throughout its geographic range. On the southern Brazilian shelf, catches of adults in research trawl surveys declined by 90% between 1972 and 2002, equivalent to a population reduction of 88% over three generation lengths (28 years). In Uruguay, landings peaked at over 3,200 t in 1999 and have declined steadily since. This fishery was considered over-exploited by 2006. Similar levels of unmanaged exploitation are suspected to be leading to declines in Argentina. This species has a similar geographic and depth distribution to the Critically Endangered Striped Smoothhound (Mustelus fasciatus). Overall, due to the intense and largely unmanaged fishing pressure it is exposed to throughout its range, its lack of refuge at depth, and documented declines, it is suspected that the Narrownose Smoothhound has undergone a population reduction of >80% over the past three generations (28 years), and it is assessed as Critically Endangered A2bd. Fil: Pollom, R.. University Fraser Simon; Canadá Fil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Herman, K.. Georgia Aquarium; Estados Unidos Fil: Montealegre-Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos ; Uruguay Fil: Rincon, G.. Universidade Federal Do Maranhao.; Brasil

The Freckle Sandskate (Psammobatis lentiginosa) is a small (to 55 cm total length) skate that occurs in the Southwest Atlantic from Rio Grande do Sul, Brazil to Chubut Province, Argentina. It inhabits the continental shelf at depths of 28-170 m. It is captured in demersal trawl fisheries, which are intense in parts of its range. Its small size and continued abundance in catches without evidence of a decline indicates that it may be productive enough to withstand some fishing pressure, and the population is suspected to be stable. Therefore, the Freckle Sandskate is assessed as Least Concern. Fil: Pollom, R.. University Fraser Simon; Canadá Fil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Faria, V.. Universidade Federal Do Ceara; Brasil Fil: Herman, K.. Georgia Aquarium; Estados Unidos Fil: Montealegre Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Uruguay Fil: Rincon, G.. Universidade Federal Do Maranhao.; Brasil

Krefft's Blind Numbfish (Benthobatis kreffti) is a small (to 30 cm total length) deep-water ray that occurs in the Southwest Atlantic from São Paulo to Rio Grande do Sul, Brazil. It is benthic on the continental slope at depths of 450–530 m. It is captured in deep-water demersal trawl fisheries, which developed rapidly in the 1990s and early 2000s in Brazil and remain intense and unmanaged. Overall, due to the level of unmanaged fishing pressure it is exposed to and its lack of refuge at depth, it is suspected that Krefft's Blind Numbfish has undergone a population reduction of 30–49% over the past three generations (15 years), and it is assessed as Vulnerable A2d. Fil: Pollom, R.. University Fraser Simon; Canadá Fil: Barreto, R.. Instituto Chico Mendes de Conservação Da Biodiversidade; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Faria, V.. Universidade Federal Do Ceara; Brasil Fil: Herman, K.. Georgia Aquarium; Estados Unidos Fil: Montealegre Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Uruguay Fil: Rincon, G.. Universidade Federal Do Maranhão; Brasil

The Shortnose Eagle Ray (Myliobatis ridens) is a medium-sized (to 70 cm disc width) ray that occurs in the Southwest Atlantic from Santa Catarina, Brazil, to Buenos Aires Province, Argentina. It inhabits inshore bays and estuaries at depths of 5-47 m. It is captured in intense and largely unmanaged artisanal gillnet and beach seine fisheries throughout much of its geographic range. The meat from this species may be consumed or sold locally or discarded. In Rio Grande do Sul, beach seine and drifting gillnet fisheries are intense and capture this species in relatively high numbers. Eagle rays, in general, declined in that state by 91% in research trawls between 1974 and 2005. Gillnets are used in Argentina to target elasmobranchs, including eagle rays, and it is suspected that declines have occurred there due to overfishing. Overall, due to the level of intense and largely unmanaged fisheries that operate throughout its range, its lack of refuge at depth, its unproductive life history, and noted declines in eagle rays in general, it is suspected that the Shortnose Eagle Ray has undergone a population reduction of >80% over the past three generations (18 years), and it is assessed as Critically Endangered A2bd. Fil: Pollom, R.. University Fraser Simon; Canadá Fil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Herman, K.. Georgia Aquarium; Estados Unidos Fil: Montealegre Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Uruguay Fil: Rincon, G.. Universidade Federal Do Maranhao.; Brasil

The Smalleye Hammerhead (Sphyrna tudes) is a medium-sized (to 150 cm total length) shark that occurs in the Western Central and Southwest Atlantic from Colombia to the Rio de La Plata, Argentina. It inhabits inshore waters over the continental shelf at depths of 5–80 m. It is captured in intense and largely unmanaged commercial and artisanal beach seines, gillnets, longlines, and trawls throughout its geographic range. This shark is targeted or retained as bycatch for its meat, which is consumed or sold locally. There are few data on population reduction but these intensive unmanaged fisheries are suspected to have caused reductions and possibly local extinctions throughout this species' range. For example, in Brazil, this hammerhead has not been recorded in 35 years from Ceará state and it is considered by local fishers to be depleted in Bahia state. This shark is supposed to be strictly protected in Brazil, but it is clear that it is still landed and traded in various states. Overall, due to intense and largely unmanaged fisheries across its range, lack of refuge at depth, suspected declines in many areas and local extinctions suspected from an absence of records (despite continued sampling and observation), and its relatively unproductive life history, it is suspected that the Smalleye Hammerhead has undergone a population reduction of >80% over the past three generations (37 years), and it is assessed as Critically Endangered A2bd. Fil: Pollom, R.. University Fraser Simon; Canadá Fil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Faria, V.. Universidade Federal Do Ceara; Brasil Fil: Herman, K.. Georgia Aquarium; Estados Unidos Fil: Lasso Alcala, O.. Fundación la Salle de Ciencias Naturales; Venezuela Fil: Marcante, F.. Universidade Federal Do Rio Grande.; Brasil Fil: Mejía Falla, P.A.. Wildlife Conservation Society; Estados Unidos Fil: Montealegre Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Navia, A. F.. Fundación Squalus; Colombia Fil: Nunes, J.. Universidade Federal Do Maranhao.; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Uruguay Fil: Rincon, G.. Universidade Federal Do Maranhao.; Brasil

The Freckled Catshark (Scyliorhinus haeckelii) is a small (to 57 cm total length) shark that occurs in the Southwest Atlantic from Bahia, Brazil to northern Argentina. It inhabits the continental shelf and upper slope at depths of 37-402 m, and is often associated with deep-water reefs. This catshark is captured in artisanal and commercial trawl, gillnet, and longline fisheries, and is increasingly retained and sometimes targeted. Fishing pressure is present across its range and is intense in some places, however there are very few data on its catchability and level of interaction with fisheries. Association with deepsea corals indicates that it may have some refuge from trawls over untrawlable areas. Since it is unknown if fishing is causing a population reduction, there is currently inadequate information available to assess the Freckled Catshark beyond Data Deficient. Fil: Pollom, R.. University Fraser Simon; Canadá Fil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Herman, K.. Georgia Aquarium; Estados Unidos Fil: Montealegre Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Uruguay Fil: Rincon, G.. Universidade Federal Do Maranhao.; Brasil

The Zipper Sandskate (Psammobatis extenta) is a small (to 35 cm total length) skate that occurs in the Southwest Atlantic from Rio de Janeiro, Brazil to the San Jorge Gulf, Santa Cruz, Argentina. It inhabits the continental shelf at depths of 13-160 m. It is caught in commercial and artisanal demersal trawl fisheries, which are intense in parts of its range, and is typically discarded dead where caught. This species is still caught commonly in fisheries despite a long history of fishing pressure and it is not suspected to be close to reaching the population reduction thresholds. Therefore, the Zipper Sandskate is assessed as Least Concern. Fil: Pollom, R.. University Fraser Simon; Canadá Fil: Barreto, R.. Instituto Chico Mendes de Conservacao Da Biodiversidade; Brasil Fil: Charvet, P.. Universidade Federal do Paraná; Brasil Fil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); Argentina Fil: Cuevas, J. M.. Wildlife Conservation Society; Estados Unidos Fil: Herman, K.. Georgia Aquarium; Estados Unidos Fil: Montealegre Quijano, S.. Universidade Federal de Sao Paulo; Brasil Fil: Motta, F.. Universidade Federal de Sao Paulo; Brasil Fil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; Uruguay Fil: Rincon, G.. Universidade Federal Do Maranhao.; Brasil

Our recent work analyses the accuracy of group recommenders when using information about the personality and the social connections between the members of the group. The goal in this paper is the use of personality and trust as the mean to define alliances to reach agreements inside a group of people. The approach reproduces the behaviour of real users when negotiating a common item to consume using three variables: personality, trust and personal preferences. We run an experiment in the movie recommendation domain where we use a personality test to identify the group leaders and test the number of people they are able to convince about a certain item to consume.

In this paper we introduce our application HappyMovie, a Facebook application for movie recommendation to groups. This system takes advantage of social data available in this social network to promote fairness for the provided recommendations. Group recommendations are based in the individual satisfaction of each individual. The (in)satisfaction of users modifies the typical aggregation functions used to estimate the value of an item for the group. This paper proposes a memory of past recommendations to compute the satisfaction of users when similar items (movies, in this case) are recommended several times.

This paper presents a description of Human System Audit (HSA), as an integrated proposal for the assessment of intangibles,for quality assessment in excellence models and, in general, for diagnosis and intervention in the human system in organizations, as well as for research on organizational human behaviour. The HSA consists of a theoretical model, a battery of instruments, and a system for management control. The article also describes some applications of HSA to human resource management.

10 pages, 5 figures, [EN]Harmful algal blooms of phytoplankton organisms are recurring events in coastal waters. Many HAB species have complex life cycles, including stages with markedly different morphological and physiological characteristics, i.e. single cells and colonies, alternation between dormant/ quiescent phases, growth stages responsible for biomass increase and benthic cysts and other resting stages capable of withstanding hostile environmental conditions. Life cycles have important implications for the occurrence and bloom dynamics of harmful species. In this study, we present the main characteristics of the life cycle for the dinoflagellate and diatom group, with the emphasis in the more recent and relevant results., [ES]Las proliferaciones algales nocivas (PANs) son eventos recurrentes en aguas costeras de todos los países. Muchas especies algales tienen ciclos de vida complejos que incluyen fases con características morfológicas y fisiológicas muy diferentes. Por ejemplo: células y colonias, alternancia entre fases de dormición, tasas de crecimiento responsables de un incremento notable de la biomasa y quistes de resistencia. Los ciclos de vida tienen implicaciones importantes en la ocurrencia y la dinámica de las proliferaciones de las especies nocivas. En este trabajo se presentan las características principales de los ciclos de vida de los dinoflagelados y las diatomeas, haciendo énfasis en los aspectos relevantes y más recientes., Agradecemos la financiación de la Comunidad Europea del proyecto FP6 SEED (Life cycle transformations among HAB species, and the environmental and physiological factors that regulate them, GOCECT-2005-003875). E. Garcés disfruta de un contrato “Ramón y Cajal” del Ministerio de Educación y Ciencia de España. R. Figueroa tiene un contrato I3P del Consejo Superior de Investigaciones Científicas de España. S. Quijano disfruta de una beca PROMEP de la Secretaría de Educación Pública, México y Universidad de Colima, México.

To present the fitest classification and the imaging peculiarities of the malformations of cortical development, most of which have been related with the epilepsy origin.The study is based on an anatomical-histological classification scheme that shows three great groups of malformations of cortical development: 1. Malformations due to abnormal neuronal and glial proliferation. 2. Malformations due to abnormal neuronal migration. 3. Malformations due to abnormal cortical organization.The result of these abnormalities of the cortical development is the presence of several anatomical histological entities, actually perfectly identified by the magnetic resonance (MR), especially with the new high resolution methods. The most frequent entities, such as polymicrogyria, lissencephaly, pachygyria, schizencephaly, cerebral heterotopia (cortical, subcortical or subependymal), and other rarer types are reviewed according with the numerous references of the literature and the findings observed in the cases of our series of about one hundred patients which includes cases of every type of malformation.MR is a conclusive study in order to identify and classify the malformations of cortical development, most of which are associated with neurological disturbances: epilepsy, mental retardation, language and/or behavioral problems or motor dysfunction.