Place feeders close to windows to reduce collisions

Overall effectiveness category Likely to be beneficial
Number of studies: 1
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How is the evidence assessed?

Effectiveness

44%
Certainty

43%
Harms

0%

Calculating overall effectiveness category

Background information and definitions

In urban environments, many people feed garden birds in front of their windows, potentially increasing the risk of birds flying into windows. Determining how distance from windows affects collision rates is therefore very important. Other interventions designed to reduce collisions with windows are discussed in ‘Threat: Residential and commercial development’.

Study locations

Key messages

A randomised, replicated and controlled experiment in the USA found that placing bird feeders close to windows reduced the number of collisions with the windows and the number of fatal collisions.

About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

A randomised, replicated and controlled experiment between October and December 1991 in Pennsylvania, USA (Klem et al. 2004), found that there were fewest collisions and fatal collisions with windows when platform feeders were placed 1 m away from the window (24% of the 105 collisions, none fatal), compared with when feeders were 5 m (28% of collisions, 33% of fatalities) or 10 m from the window (48% and 67%). Similarly, in a repeat experiment in February 1992, there were fewest collisions and fatalities when feeders were 2m from the window (23% of 197 collisions, 5% of 21 fatalities) than 3 m (46% and 43%) or 4 m (31% and 52%) away. The proportion of collisions that were fatal increased with distance that feeders were from windows from 0% at 1 m away and 2% at 2 m to 59% at 5 m and 69% at 10 m. Six plate glass, wooden framed windows (1.4 x 1.2 m, 1.2 m off the ground, 55 m apart) and six platform feeders (with the platform level with the base of each window) were used on the edge of deciduous woodland and farmland.
Study and other actions tested
Referenced paper
Klem D. Jr., Keck D.C., Marty K.L., Miller Ball A.J., Niciu E.E. & Platt C.T. (2004) Effects of window angling, feeder placement, and scavengers on avian mortality at plate glass. The Wilson Bulletin, 116, 69-73.

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. (2020) Bird Conservation. Pages 137-281 in: W.J. Sutherland, L.V. Dicks, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2020. Open Book Publishers, Cambridge, UK.

Where has this evidence come from?

List of journals searched by synopsis

All the journals searched for all synopses

This Action forms part of the Action Synopsis:

Bird Conservation

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