grazing: Bird abundance in grazing areas
In rdmatheus/bergreg: BerG Regression for Count Data

Description Usage Format Details References

The density of understorey birds at a series of sites in two areas either side of a stockproof fence.

1	data(grazing)

A data frame with 62 observations on the following 3 variables.

birds: the number of understorey birds; a numeric vector.
when: when the bird count was conducted; a factor with levels Before (before herbivores were removed) and After (after herbivores were removed).
grazed: which side of the stockproof fence; a factor with levels Reference (grazed by native herbivores) and Feral (grazed by feral herbivores, mainly horses).

In this experiment, the density of understorey birds at a series of sites in two areas either side of a stockproof fence were compared. Once side had limited grazing (mainly from native herbivores), and the other was heavily grazed by feral herbivores, mostly horses. Bird counts were done at the sites either side of the fence (the Before measurements). Then the herbivores were removed, and bird counts done again (the After measurements). The measurements are the total number of understorey-foraging birds observed in three 20-minute surveys of two hectare quadrats.

Alison L. Howes, Martine Maron and Clive A. McAlpine (2010) Bayesian networks and adaptive management of wildlife habitat. Conservation Biology. 24(4), 974-983.2.

rdmatheus/bergreg documentation built on Dec. 22, 2021, 1:04 p.m.