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Providing evidence to improve practice

Individual study: Gill nets hung vertically in the water and harassment patrols are ineffective in deterring fish predation by cormorants Phalacrocorax spp. at silver perch Bidyanus bidyanus fish-rearing ponds, New South Wales, Australia

Published source details

Rowland S.J. (1995) Predation of Bidyanus bidyanus (Teraponidae) in ponds by cormorants. The Progressive Fish-Culturist, 57, 248-249


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Use in-water devices to reduce fish loss from ponds Bird Conservation

A replicated study at four silver perch Bidyanus bidyanus rearing ponds in New South Wales, Australia, found that hanging of gill nets and harassment patrols proved ineffective in deterring cormorants (great Phalacrocorax carbo, little black P. sulcirostris and little pied P. melanoleucos) from fishing in the ponds (Rowland 1995). Gill nets (large diameter mesh enabling young fish to swim through) were hung vertically in the water and harassment patrols (people walking around the ponds) were undertaken. Three ponds of 0.1 ha were stocked with fry (50,000-60,000 fish/ha) and one of 0.3 ha stocked with fingerlings (8,000/ha). Survival rates of fry in the three smaller ponds was 0.3%, 0.8% and 3.5% (average 1.5%), and survival of fingerlings 0.9%.

 

Disturb birds using foot patrols Bird Conservation

A replicated trial in New South Wales, Australia (Rowland 1995), found that hanging gill nets in fish ponds and using harassment patrols to deter cormorants Phalacrocorax spp. from fish farms was not effective. This study is discussed in ‘Use in-water devices to reduce fish loss from ponds’.

 

Scare birds from fish farms Bird Conservation

A replicated trial in New South Wales, Australia (Rowland 1995), found that hanging gill nets in fish ponds and using harassment patrols to deter cormorants Phalacrocorax spp. from fish farms was not effective. This study is discussed in ‘Use in-water devices to reduce fish loss from ponds’.