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Providing evidence to improve practice

Individual study: Predator exclosures with electric fences increase nesting success of dabbling ducks Anas spp. and the proportion of females nesting within exclosures increases over time

Published source details

Cowardin L.M., Pietz P.J., Lokemoen J.T., Sklebar H.T. & Sargeant G.A. (1998) Response of nesting ducks to predator exclosures and water conditions during drought. The Journal of Wildlife Management, 62, 152-163


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Protect bird nests using electric fencing Bird Conservation

A replicated, controlled trial from 1987-1991 in three wetland-grassland sites in North Dakota and Minnesota, USA (Cowardin et al. 1998) found that using fencing (1.8 m tall with an electrified top wire and with ground-level openings to allow broods to leave) to exclude mammalian predators from 25 ha of nesting habitat significantly increased the nesting success of dabbling ducks Anas spp. (75% of 452 nests inside exclosures), compared to those nesting outside exclosures (no data provided for control). The proportion of nests inside exclosures compared with control areas increased signifcantly for mallard A. platyrhynchos, gadwall A. strepera, blue-winged teal A. discors and northern pintail A. acuta, but not for northern shoveler A. clypeata and dabbling ducks. The authors note that there was a local and regional decline in dabbling duck numbers over the study period, probably due to an ongoing drought.