Fábio Vieira

Impacts of Non-Native Fish Species in Minas Gerais, Brazil: Present Situation and Prospects

For some time, the rate of non-native fish introductions has been increasing in South America. There are many reasons for introductions: reservoir stocking programs, aquaculture, sport fishing, control of disease vectors, and the pet trade. Accidental escapes also contribute significantly. In Brazil, despite federal and state regulations, there are misunderstandings about such concepts as native, exotic, allochthonous, or autochthonous fishes and introductions, translocations, reintroductions, and transfers of fishes. Known impacts of exotic fishes include native species extinction, changes in competition and predation rates, limnological perturbations, introduction of diseases and parasites, hybridization with native species, and changes in fisheries composition. The few recorded benefits of non-native species introductions are restricted to the improvement of fish production and sport fisheries. In Minas Gerais, Brazil, records of exotic species have increased over the past seven years. In some of the most important river basins of that state, alien fish species might represent up to 40% of the fish fauna. Congeneric species, such as Hyphessobrycon bifasciatus and the exotic H. eques, can be captured from the same water body and the non-native species can be much more abundant than the native species. The recent introduction of Leporinus macrocephalus from the Pantanal may cause the same impact to the native L. copelandii. The widespread introduction of the peacock bass and other piscivorous species is the cause of local extinctions in the central lake of Lagoa Santa and in the

A better way forward for Brazil's fisheries.

In December 2014, the Brazilian Minister of the Environment released the new national red lists enumerating 2113 plants and 1173 animals threatened with extinction ([ 1 ][1]). Of the 475 aquatic species on the list, 83 are commercially exploited by fisheries, mainly as by-catch. The industrial

Brazilian aquatic biodiversity in peril

The ongoing fiscal and political crisis in Brazil has already caused deep cuts to science and education (“Fiscal crisis has Brazilian scientists scrambling,” H. Escobar, In Depth, 28 August, p. [909][1]), and now the environment is in the crosshairs. On 2 October, the Federal Government

Presence of the walking catfish Clarias gariepinus (Burchell) (Siluriformes, Clariidae) in Minas Gerais state hydrographic basins, Brazil

The first official occurrence of the exotic species Clarias gariepinus (Burchell, 1822) in the Rio Paraopeba (Sao Francisco river basin), the Rio Grande (Parana river basin), and the Rio Doce (Doce river basin), is reported, with comments on the possible ecological consequences and on the conservation of freshwater fish biodiversity due to non-native species introductions.

Pareiorhaphis scutula, a new species of neoplecostomine catfish (Siluriformes: Loricariidae) from the upper rio Doce basin, Southeastern Brazil

Pareiorhaphis scutula, new species, is described from the headwaters of the rio Piracicaba, tributary to the upper rio Doce basin in the State of Minas Gerais, southeastern Brazil. The new species is distinguished from all congeners by having an unique autapomorphic feature: the abdominal surface from pectoral girdle to pelvic-fin insertions covered with small platelets imbedded in skin and irregularly scattered. This feature is not shared with any other Pareirhaphis species. Pareiorhaphis scutula is further compared with the sympatric P. nasuta.

Threatened fishes of the world: Henochilus wheatlandii Garman, 1890 (Characidae)

onio River tributary, Doce river basin. Abundance: No abundance data available. Local people mention the species as frequent but not abundant. Habitat and ecology: The stream where the specimens were found is relatively narrow, with depth varying from 0.5 to 1.5 m and has dark colored waters. Substrate is mostly sandy, with large boulders forming alternate riffles and eddy pools. Riparian vegetation is relatively well preserved. The water is slightly acid, with low nutrient concentrations. H. wheatlandii seems to be dependent on undisturbed areas, and requires special habitat conditions, mostly related to stream order, substrate features and water quality. This hypothesis can be

Utilização do mecanismo de transposição de peixes da Usina Hidrelétrica Santa Clara por camarões (Palaemonidae), bacia do rio Mucuri, Minas Gerais, Brasil

Durante a operacao do elevador para peixes da Usina Hidreletrica Santa Clara, de novembro de 2003 a marco de 2004, todos os crustaceos palaemonideos adultos que utilizaram o mecanismo foram contados e o numero de jovens estimado. Duas especies foram registradas: Macrobrachium carcinus (Linnaeus, 1758) e Macrobrachium acanthurus (Wiegmann, 1836). A utilizacao do mecanismo por adultos foi bastante restrita, com apenas 185 exemplares registrados. Porem, o numero de jovens de M. carcinus utilizando o elevador foi estimado em 19.120 individuos. Embora o mecanismo avaliado tenha permitido a passagem dos palaemonideos para montante do barramento, ficou clara a necessidade de novos arranjos estruturais e de manejo especificos para esses animais. Essas acoes se referem ao desenvolvimento de estruturas direcionadas para a sua passagem e a adocao de vertimentos programados durante o periodo reprodutivo para permitir o carreamento de larvas para jusante. Esses dois caminhos representam formas efetivas de manejo, imprescindiveis para a manutencao das populacoes deste importante componente da biota aquatica.

Threatened fishes of the world: Delturus parahybae Eigenmann & Eigenmann, 1889 (Loricariidae)

Common name: Cascudo (Por). Conservation status: No official designation. Mazzoni et al. (2000) considered the species as data deficient and possibly endangered. Identification: One of three species of the genus Delturus, distinguished by the presence of black rounded spots on head and dorsum of body, and 26–28 lateral dermal plates in lateral median series. Caudal peduncle flattened ventrally and abdomen entirely naked. Adipose fin present. Mandibular ramus about 1.3 times in interorbital width. Lateral borders of head and first thickened pectoral-fin ray of adult males with bristle-like hypertrophied odontodes. D i + 9, A i + 5, P1 i + 6, P2 i + 5, C i + 14 + i. Scientific description in Eigenmann & Eigenmann (1889). Distribution: Restricted to the Paraı́ba do Sul River basin, southeast Brazil, with records only for two localities: Paraı́ba do Sul River, between Três Rios and Barra do Piraı́ counties – Rio de Janeiro state, and Pomba River, near Laranjal county – Minas Gerais state. Abundance: No abundance data available. Only four individuals are known. The two syntypes (MCZ 7726), were sampled in 1865. Another specimen was collected in 1908 (FMNH 59734). These records were from Paraı́ba do Sul River main channel. After that, intense collecting expeditions in large portions of the basin did not locate the species, although the type locality was fished and more than 35 000 other fishes were collected . There is only one recent record, the specimen captured in Pomba River (MCP 27296) in 1997. These facts suggest that the species is presently very rare, possibly extinct or in the process of becoming extinct in a large part of the Paraı́ba do Sul River basin. Habitat and ecology: The fourth available D. parahybae specimen was captured in the Pomba River rapids. The rocky substrate was partially covered by aquatic vegetation (Podostemaceae). At this region, Rio Pomba is 30 m wide and 0.5–2.0 m deep. Riffles and pools are alternating. This habitat preference is the same of the congeneric species found in Doce and Mucuri River basins. There is no other ecological information for this species. Reproduction: Reproductive requirements are unknown. Threats: The Paraı́ba do Sul watershed is one of the most industrialized and urbanized Brazilian region, with several riverine sections experiencing pronounced environmental degradation. According to Eletrobrás (1999) there are 14 hydropower plants in operation and more than 50 planned or under construction in the basin. Reservoirs are responsible for alteration or elimination of the lotic habitat occupied by this species, and together with domestic and industrial untreated wastes, represent the major threats to long-term species maintenance. Conservation actions: Pomba river has recently been recognized as an ‘Extreme Biological Importance’ region, the second highest priority category for conservation in Minas Gerais state (Costa et al. 1998). Conservation recommendations: Evaluation of the current distribution of D. parahybae in the Paraı́ba do Sul basin and biological studies are needed. Environmental restoration programs of the basin, with special attention paid to water quality improvement and maintenance of riverine sections with the original lotic flow patterns. Revaluation of the conservation status and inclusion of the species in IUCN and Brazilian official lists as ‘endangered’. Remarks: The congeneric species D. carinotus and D. angulicauda are found in higher abundance in the rapids of Doce and Mucuri River basins (personal observation). This fact suggests the lack of available habitats for D. parahybae as well as it’s extreme vulnerability to environmental degradation.