Table 1 Probability distributions used for parameters in cat predation model.

From: The impact of free-ranging domestic cats on wildlife of the United States

Parameter Number of studies used* Distribution type Distribution parameters
Owned cats
 Number of owned cats in contiguous United States 2 Normal Mean=84 M, s.d.=2.5 M
 Proportion of owned cats with outdoor access 8 Uniform Min=0.4, max=0.7
 Proportion of outdoor owned cats that hunt 3 Uniform Min=0.5, max=0.8
 Correction for owned cats not returning prey 3 Uniform Min=1.2, max=3.3
BIRD return rate per cat per year
 US studies 4 Uniform Min=1.0, max=34.1
 US and Europe studies 11 Uniform Min=4.2, max=18.3
 All temperate studies 17 Uniform Min=3.4, max=13.2
MAMMAL return rate per cat per year
 US studies 1 NA† NA
 US and Europe studies 7 Uniform Min=11.1, max=29.5
 All temperate studies 13 Uniform Min=8.7, max=21.8
REPTILE return rate per cat per year
 US studies 0 NA NA
 US and Europe studies 1 NA NA
 All temperate studies 8 Uniform Min=0.4, max=2.21
AMPHIBIAN return rate per cat per year
 US studies 0 NA NA
 US and Europe studies 1 NA NA
 All temperate studies 5 Uniform Min=0.05, max=0.5
Un-owned cats
 Number of un-owned cats in contiguous United States 5 Uniform Min=30 M, max=80 M
 Proportion of un-owned cats that hunt 2 Uniform Min=0.8, max=1.0
BIRD predation rate per cat per year
 US studies 8 Uniform Min=24.4, max=51.4
 US and Europe studies 11 Uniform Min=23.2, max=46.2
 All temperate studies 19 Uniform Min=30.0, max=47.6
MAMMAL predation rate per cat per year
 US studies 6 Uniform Min=162.3, max=354.9
 US and Europe studies 7 Uniform Min=139.4, max=328.6
 All temperate studies 13 Uniform Min=177.3, max=299.5
REPTILE predation rate per cat per year
 US studies 1 NA NA
 US and Europe studies 2 NA NA
 All temperate studies 10 Uniform Min=4.2, max=12.4
AMPHIBIAN predation rate per cat per year
 US studies 0 NA NA
 US and Europe studies 0 NA NA
 All temperate studies 3 Uniform Min=1.9, max=4.7
  1. *Number of studies found that include an estimate of the model parameter.
  2. No calculation was conducted for this data grouping because of limited data.