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

Actions

This study is summarised as evidence for the following.

Action Category

Use in-water devices to reduce fish loss from ponds

Action Link
Bird Conservation

Disturb birds using foot patrols

Action Link
Bird Conservation

Scare birds from fish farms

Action Link
Bird Conservation
  1. Use in-water devices to reduce fish loss from ponds

    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%.

     

  2. Disturb birds using foot patrols

    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’.

     

  3. Scare birds from fish farms

    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’.

     

Output references

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