Fishing nets - Active fishing gear
Purse (pelagic) seine net
Purse seine nets are used for catching all age and size classes of fish in open water. The principle is to surround fishes with a wall of netting and to capture them inside a net cone. The haul is carried out in the open water and the net is not pulled towards the shore.
General principles for using a purse seine net
Purse seine nets are handed out from the fast moving boat in a circle to surround a fish shoal. The boat finishes at the place where it starts.
Constriction of the bottom part of the net perimeter results in capturing fishes. The net is then pulled out of the water to a boat at the place of the haul.
It is necessary to rearrange the net on the boat in order to be ready before the next haul.
Success of the capture is dependent not only on presence of fishes in sampled area, but also highly on the speed of a boat during the handing out of the net.
A purse seine net consists of a shaped strip of netting with the top line with floats and the bottom and side line with a lead line and guiding rings. A separate rope goes through the rings and is used for closing the net. Shapes and sizes of purse seine nets vary according to application.
For scientific research we produce purse seine nets of two well-proven standard sizes:
Fry purse seine net:
| Material | Mesh size | Length | Depth |
|---|---|---|---|
| Tulle - PES | 1,5x2 mm | 50m | 6m |
Adult purse seine net:
| Material | Mesh size | Length | Depth |
|---|---|---|---|
| Netting - PA | 5 mm - 210/2 7 mm - 210/4 10 mm - 210/6 | 120 m contains: 30 m - MS 5mm 45 m - MS 7mm 45 m - MS 10mm | 12m |
Sampling with a purse seine net in the Římov Reservoir
References:
Tischler, G., Gassner, H. & Wanzenböck, J. (2000). Sampling characteristics of two methods for capturing age-0 fish in pelagic lake habitats. Journal of Fish Biology 57, 1474-1487