Publication details
Srovnání účinnosti různých technik elektrolovu juvenilních ryb na říčních plážích
| Title in English | Comparison of efficiency of different electrofishing techniques for juvenile fish estimates on river beach |
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| Authors | |
| Year of publication | 2004 |
| Type | Article in Proceedings |
| Conference | 7. Česká ichtyologická konference |
| MU Faculty or unit | |
| Citation | |
| Field | Zoology |
| Keywords | juvenile fish |
| Description | The efficiency of three PAS electrofishing techniques (direct electrofishing, throwing of anode and remote electrofishing) for 0+ juvenile fish estimates was tested on gravel beaches of the Morava River. During direct electrofishing the operator personally immerges anode fasten on an extension pole. During throwing, anode is thrown from a distant place on the bank. During remote electrofishing, prepositioned anode is activated after fish recolonize the area. All three techniques yielded significantly different assemblage structure (in terms of relative abundances of most abundant species). Both direct electrofishing and throwing of anode disturbed fish, what lowered their efficiency on these shallow habitats (30% in comparison with remote electrofishing). Meanwhile direct electrofishing disturbed fish mainly by presence of operator, throwing of anode disturbed fish mainly by falling of anode on the water surface. Therefore throwing of anode was more sensitive to species that occur near the water surface (e.g. bleak). Remote electrofishing proved to be the most suitable technique for sampling juvenile fish at beaches. It was the most effective technique, moreover it yielded significantly more species per locality than other two techniques. Higher time consumption, caused by higher number of fish caught, may be its only constrain in common monitoring, however it is negligible in comparison with its benefits. |