Action Synopsis: Soil Fertility About Actions

Encourage foraging waterfowl

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

Study locations

Key messages

One controlled, replicated experiment from the USA found increased straw decomposition when ducks were allowed to forage.



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, replicated experiment in 1995-1996 on a silty clay soil in California, USA (Bird et al, 2000) found that waterfowl foraging activity increased straw decomposition by 78% in untilled plots and 18% in rolled plots (a roller crushes crop remains into the soil) compared to their respective un-foraged plots. Foraging and field tillage reduced nitrogen concentrations in the remaining straw residue at the end of the winter fallow period. Mallards did not incorporate the straw. Individual field plots (25 m2) were subjected to two post-harvest treatments: wet-rolled (field tillage) or untilled, replicated four times. Within these treatments, Mallard Anas platyrhynchos ducks were placed on one half of the plots, equivalent to 33 birds/ha from 1-18 February. Ten soil samples were taken from each plot on five sampling occasions. The study measured levels of residual rice straw and below-ground organic matter (carbon and nitrogen).

    Study and other actions tested
Please cite as:

Key, G., Whitfield, M., Dicks, L.V., Sutherland, W.J. & Bardgett, R.D. (2020) Enhancing Soil Fertility. Pages 613-634 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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Soil Fertility

This Action forms part of the Action Synopsis:

Soil Fertility
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