Mário Luís Orsi

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Brazil has a highly diverse freshwater fish fauna and their freshwaters provide valuable provisioning ecosystem services in aquaculture and sport angling, especially in the developed regions in the south. Non-native fish now comprise a substantial proportion of the total aquaculture production and value, contributing at least $US 250 million in 2008 (63% of(More)
Quantifying and classifying ichthyoplankton is one of the most effective ways of monitoring the recruitment process in fishes. However, correctly identifying the fish based on morphological characters is extremely difficult, especially in the early stages of development. We examined ichthyoplankton from tributaries and reservoirs along the middle stretch of(More)
The changes in the fish assemblage of the Capivara Reservoir, Brazil, were assessed over a 20 year period. Of 50 native fishes present in the initial samples, 27 were no longer present in the final samples, but there had been an addition of 11 invasive fishes, suggesting the occurrence of substantial shifts in fish diversity and abundance.
André A. Padial • Ângelo A. Agostinho • Valter M. Azevedo-Santos • Fabrı́cio A. Frehse • Dilermando P. Lima-Junior • André L. B. Magalhães • Roger P. Mormul • Fernando M. Pelicice • Luis A. V. Bezerra • Mário L. Orsi • Miguel Petrere-Junior • Jean R. S. Vitule Received: 24 June 2016 / Revised: 30 September 2016 / Accepted: 3 October 2016 / Published online:(More)
The executive and legislative branches of Brazilian government have either proposed or taken a variety of initiatives that threaten biodiversity and ecosystems. Opposition by the scientific community has largely been ignored by decision-makers. In this short essay, we present recent examples of harmful policies that have great potential to erode(More)
Currently, biodiversity is threatened by several factors often associated with human population growth and the extension of areas occupied by human activity. In particular, freshwater fish fauna is affected by overfishing, deforestation, water pollution, introduction of exotic species and habitat fragmentation promoted by hydroelectric dams, among other(More)
The objective of our study was to evaluate the efficacy of DNA barcoding as a tool to identify non-native fish in their early stages of life. Specimens were collected from 14 sites in the lower and middle regions of the Paranapanema River—the main tributary of the Upper Paraná River basin in southern Brazil. Over three reproductive periods from 2012 and(More)
BRAZIL, WHICH HAS the world’s largest renewable water supplies, has recently experienced water shortages, and therefore energy crunches, caused by its worst drought since 1930 (1). The water crisis has spread across large areas of the country’s breadbasket region—southeast Brazil—affecting crop production, industrial activities, and millions of people.(More)
Understanding the pathways and impacts of non-native species is important for helping prevent new introductions and invasions. This is frequently challenging in regions where human activities continue to promote new introductions, such as in Brazil, where aquaculture and sport fishing are mainly dependent on non-native fishes. Here, the non-native fish(More)
The aim of this study is to report the presence of a three non-native hybrid long-whiskered catfishes (family Pimelodidae) in the Upper Paraná River basin, Brazil. Genetic analyses demonstrated that the three presumptive hybrids were a result of the crossbreeding of Pseudoplatystoma reticulatum (central Amazonas River basin and Lower Paraná River) and(More)