What is it about?

River basins present a differential fish fauna due to unique environmental characteristics and independent evolutionary history. These differences are part of the biodiversity value of a region. The introduction of alien species in Spanish river basins are making their species composition more similar, diminishing the biodiversity value of the region, even when no native species extinction has been recorded. This phenomenon is affecting all river basins independent of their size and hydrological alteration

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Why is it important?

Our results indicate that the effects of species introductions should be analysed through time (several decades) since it is a temporally and spatially dynamic process. In our study, negative effects because of the introduction of an exotic species in a river basin become higher due to its continuous expansion to the rest of the river basins.


I hope that this article will reinforce the idea that spatial diversity is a great value. That to find different things in different places is the right way. That the need to travel to see something (or to fish a given species) is not an annoyance but one of the best reasons for travelling.

Juan A. Delgado
Universidad Complutense de Madrid

Read the Original

This page is a summary of: Species introduction and taxonomic homogenization of Spanish freshwater fish fauna in relation to basin size, species richness and dam construction, Journal of Freshwater Ecology, January 2018, Taylor & Francis,
DOI: 10.1080/02705060.2018.1503101.
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