Informace o publikaci
Comparison of efficiency of different electrofishing techniques for juvenile fish estimates on river beaches
| Název česky | Porovnání účinnosti různých technik elektrolovu 0+ juvenilních ryb na říchních plážích |
|---|---|
| Autoři | |
| Rok publikování | 2004 |
| Druh | Konferenční abstrakty |
| Fakulta / Pracoviště MU | |
| Citace | |
| Popis | The efficiency of three different techniques (direct electrofishing, throwing the anode, remote electrofishing) for 0+ point abundance sampling by electrofishing was tested on gravel beaches of the Morava River during August 2003. During direct electrofishing, the operator personally imerses anode fastened on an extension pole. During throwing , anode is thrown at a distance from the bank. During remote electrofishing, the prepositioned andoe is activated after fish recolonize the area. All threee techniques yielded significantly different assemblage structures (in terms of relative abundances of most abundant species). Both direct electrofishing and throwing the anode disturbed fish and that fish tend to escape, thereby reducing efficiency of these techniques (they were only 30% as efficient as remote electrofishing). For species inhabiting the upper layer of the water column (mainly bleak), throwing the anode seemed to be more efficient than direct electrofishing. Remote electrofishing proved to be the most suitable technique for sampling juvenile fish at river beaches. It was the most effective technique and it yielded significantly more species per locality than other two techniques, Higher time consumption, which is caused by higher number of fish caught, may be its only constrain in monitoring surveys, however it is negligible in conparison with its benefits. |