Anthropogenic stressors and riverine fish extinctions
In: Ecological Indicators. Elsevier: Shannon. ISSN 1470-160X; e-ISSN 1872-7034, more | |
Author keywords | Anthropogenic threats; Extinctions; Riverine fishes; River basins |
Authors | | Top | - Dias, M.S.
- Tedesco, P.A.
- Hugueny, B.
- Jézéquel, C.
| - Beauchard, O.
- Brosse, S.
- Oberdorff, T.
| |
Abstract | Human activities are often implicated in the contemporary extinction of contemporary species. Concerningriverine fishes, the major biotic and abiotic threats widely cited include introduction of non-nativespecies, habitat fragmentation and homogenization in stream flow dynamics due to the damming ofrivers, dumping of organic loadings, degradation of the riverine habitat by agricultural practices andwater abstraction for human and agricultural consumption. However, few studies have evaluated therole of each of these threats on fish extinction at large spatial scales. Focusing on Western Europe andthe USA, two of the most heavily impacted regions on Earth, we quantify fish species loss per river basinand evaluate for the first time to what extent, if any, these threats have been promoting fish extinctions.We show that mean fish extinction rates during the last 110 years in both continents is∼112 timeshigher than calculated natural extinction rates. However, we identified only weak effects of our selectedanthropogenic stressors on fish extinctions. Only river fragmentation by dams and percentage of nonnativespecies seem to be significant, although weak, drivers of fish species extinction. In our opinion, themost probable explanation for the weak effects found here comes from limitations of both biological andthreats datasets currently available. Obtaining realistic estimates on both extinctions and anthropogenicthreats in individual river basins is thus urgently needed. |
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