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Providing evidence to improve practice

Action: Use electric fencing to exclude fish-eating birds Bird Conservation

Key messages

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Two before-and-after studies from the USA found that electric fencing reduced the use of fish ponds by great blue herons Ardea herodias and great egrets Casmerodius albus.


Supporting evidence from individual studies


Before-and-after trials in Mississippi, USA (Mott & Flynt 1995), found that a two-strand electric fence reduced pond use by great blue herons Ardea herodias and great egrets Casmerodius albus by 91%. Five ponds (0.3-2.2 ha in area) containing channel catfish Ictalurus punctatus were tested.



A before-and-after trial in August-November 1996 in Pennsylvania, USA (Tobin et al. 1997), found that electric fencing was fairly effective in deterring great blue herons Ardea herodias from raceways (long, 3-6 m wide fish ponds) at two trout hatcheries (declines from 6-14 birds/h/day and 76-159/h/day to <3 and <58 after electric fencing was erected). Fences comprised two strands of polyethylene tape (1.6 cm wide, 15-30 cm apart). Herons were counted (4 counts/week before and after installation; additional counts to 62 days after installation). Reductions in fish predation were not assessed.


Referenced papers

Please cite as:

Williams, D.R., Child, M.F., Dicks, L.V., Ockendon, N., Pople, R.G., Showler, D.A., Walsh, J.C., zu Ermgassen, E.K.H.J. & Sutherland, W.J. (2018) Bird Conservation. Pages 95-244 in: W.J. Sutherland, L.V. Dicks, N. Ockendon, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2018. Open Book Publishers, Cambridge, UK.