Fishing Gear, Craft and Harvesting Technology
Gear types
Gill nets entangle fish by the gills; cast nets are thrown and retrieved; seine nets surround and haul; drag nets scrape the bottom; lift nets and traps work on attraction or confinement. Selectivity depends on mesh size, twine, hanging ratio and where the gear fishes. Square-mesh codends reduce capture of juveniles compared with diamond mesh.
Craft and harvesting
Plank-built canoes and FRP boats are common in inland and estuarine fisheries. Harvest a pond with a seine or drag net, preferably in the cool early morning, and stop feeding before harvest to reduce stress. Keep fish in clean water briefly if purging is required.
Maintenance
Dry nets after use, remove weeds and mud, mend tears before storage, and keep boats painted and engines serviced. A net stored wet rots and loses strength.
Worked example
A manager wants to harvest market-size rohu from a 1 ha pond but leave small fish. A seine with a larger mesh and a soft, muddy bottom is preferred over a fine-mesh drag net, because the larger mesh lets small fish escape and the smooth haul reduces mud and stress. Reasoning: gear choice balances selectivity, bottom type and fish stress, not just catch volume.
Traps
- Using a fine-mesh net and calling the catch selective.
- Fishing a weedy pond with a gill net that tangles.
- Storing nets wet.
- Harvesting at midday in summer without oxygen monitoring.