Providing evidence to improve practice

Action: Mowing roadside verges Bird Conservation

Key messages

A single replicated, controlled study in the USA found that more ducks nested on unmown roadside verges, but that over four years, nesting success on unmown verges fell to below that on mown verges.

 

Supporting evidence from individual studies

1 

A replicated, controlled trial in 1969-72 in North Dakota, USA (Voorhees & Cassel 1980), found that more ducks nested in unmown than mown road verges (although this difference was not significant in 1972). However, nesting success remained between 40-60% in mowed strips, whereas it fell from >70% to <30% in unmown strips due to an increase in mammalian nest predation. Alternate mowed and unmown 1.6 km strips of roadside vegetation were compared along 37km of Interstate 94. The 23 mowed strips (totalling 123 ha) were mown once in autumn. Six duck species nested over the four years: blue-winged teal Anas discors, mallard A. platyrhynchos, gadwall A. strepera, northern shoveler A. clypeata, pintail A. acuta and lesser scaup Aythya affinis.

 

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. (2017) Bird Conservation. Pages 95-244 in: W.J. Sutherland, L.V. Dicks, N. Ockendon & R.K. Smith (eds) What Works in Conservation 2017. Open Book Publishers, Cambridge, UK.