Action Synopsis: Bird Conservation About Actions

Control predators not on islands for cranes

How is the evidence assessed?
  • Effectiveness
    not assessed
  • Certainty
    not assessed
  • Harms
    not assessed

Study locations

Key messages

A single trial from the USA found that greater sandhill cranes Grus canadensis tabida had higher hatching and fledging success in years with predator control, compared to years without control.


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

  1. A trial in southeast Oregon, USA, between 1966 and 1989 (Littlefield 2003), found that greater sandhill crane Grus canadensis tabida hatching success and fledging success were both higher in ten years when predators were controlled than in nine years without predator control (average hatching/fledging success of 55% and 9.1% for 662 clutches in predator control years vs. 42% and 5.1% for 434 in non-control years). Coyotes Canis latrans and ravens Corvus corax were controlled by poisoning and shooting. The main nest predators were coyotes (predating 17% of clutches in predator control years and 27% in non-control years), ravens (14% and 20%) and raccoons Procyon lotor (11% and 8%, the increase possibly related to a reduction in coyote numbers).

    Study and other actions tested
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

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Bird Conservation

This Action forms part of the Action Synopsis:

Bird Conservation
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What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

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