Abstract
The degradation and homogenization of natural habitats is considered a major cause of biotic homogenization. Many studies have been undertaken on the effects of dams on aquatic wildlife, in particular fish assemblages. But how do dams affect the parasitic fauna of such fish? The aim of the present study was to examine parasitic similarity, comparing the diversity and structure of parasite communities of Leporinus friderici (Characiformes, Anostomidae) in three upstream tributaries under the influence of the Jurumirim Dam on the Upper Paranapanema River in southeastern Brazil. The present study did not find any significant differences in parasite communities among populations of L. friderici in the three upstream tributaries. This result highlights that dams promote and facilitate the dispersal of organisms between localities, and therefore the spatial homogenization of parasite communities. Overall, the results suggest that fish parasite assemblages can provide suitable data for evaluating biotic homogenization caused by dams.
Highlights
Intermediate disturbance frequencies and/or intensities and other environmental fluctuations can maintain biological diversity by reducing the dominance of some species and so can shape evolutionary and ecological processes in aquatic and terrestrial ecosystems (Wilson 1990, Poff et al 2007, Rahel 2010)
Cascades of dams have been constructed on the main rivers of southeastern Brazil, altering the up- and downstream connections of the dam (Arcifa and Esguícero 2012), and producing a discontinuity along the longitudinal gradient (Gumiero and Salmoiraghi 1998)
116 specimens of L. friderici were examined for metazoan parasites, as follows: 34 specimens from the Paranapanema River (PR) with a length ranging from 8.9 to 24 cm with a median length of 18.49±4.84 (SD) cm; 36 specimens from the Taquari River (TR) with length ranging from 9.3 to 25 cm with a median length of 18.73±5.28 (SD) cm; and 46 from the Veados River (VR) with a length ranging from 9 to 27 cm with a median length of 14.59±5.79 (SD) cm
Summary
Intermediate disturbance frequencies and/or intensities and other environmental fluctuations can maintain biological diversity by reducing the dominance of some species and so can shape evolutionary and ecological processes in aquatic and terrestrial ecosystems (Wilson 1990, Poff et al 2007, Rahel 2010). Dam interventions leads to the decline of many species that are replaced by a much smaller number of expanding species that thrive in environments altered by humans (Olden and Rooney 2006, Rahel 2007). Dams are classic examples of human interventions in natural flow regimes that cause changes in the ecology of freshwater organisms by reducing natural regional differences and imposing environmental homogeneity on a large geographic scale (Poff et al 2007). Cascades of dams have been constructed on the main rivers of southeastern Brazil, altering the up- and downstream connections of the dam (Arcifa and Esguícero 2012), and producing a discontinuity along the longitudinal gradient (Gumiero and Salmoiraghi 1998)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
