Control birds

How is the evidence assessed?

Study locations

Key messages

  • One controlled study in Australia found that removing bell-miners from narrow-leaved peppermint forests did not improve the health of the trees in the forest.


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 controlled study in 1992–1995 in three sites in narrow-leaved peppermint Eucalyptus radiata forest in south eastern Victoria, Australia (Clarke & Schedvin 1999) found that the removal of bell miners Manorina melanophrys did not improve tree health. The change in tree health (an index based on crown size, crown density, the presence of dead branches and the shoot growth) did not differ between the plots where bell miners had been removed (-0.6), were present (-2.3) and a control plot where no bell miners occurred (-0.7). In June 1993, a total of 189 bell miners were removed from the experimental site and the surrounding area (2.7 ha), by mist netting and culling. The tree health index was based on the visual assessment of the health of 10 trees at each plot (50 x 50 m), following a standardized protocol.

    Study and other actions tested
Please cite as:

Agra, H., Schowanek, S., Carmel, Y., Smith, R.K. & Ne’eman, G. (2020) Forest Conservation. Pages 323-366 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

Forest Conservation

This Action forms part of the Action Synopsis:

Forest Conservation
Forest Conservation

Forest Conservation - Published 2016

Forest synopsis

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What Works in Conservation

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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