Geoscience Reference
In-Depth Information
TABLE 9.1
Parameter Estimates and Standard Errors (SE) for the Model to Describe the
Expansion of the House Finch across Eastern North America during 1976-2001 at
Five-Yearly Intervals
Parameter
Estimate
SE
Parameter
Estimate
SE
ˆ
1
ˆ
1
Occupancy
−0.83
0.41
Extinction
−3.39
0.26
ˆ
2
ˆ
2
−1.22
0.48
1.17
0.25
ˆ
1,1
ˆ
1,1
Colonization
1.43
0.59
Detection
−2.35
0.20
ˆ
1,2
ˆ
1,2
−8.17
3.13
−10.19
2.00
ˆ
2,1
ˆ
2,1
2.33
0.47
−1.80
0.09
ˆ
2,2
ˆ
2,2
−4.23
0.79
−3.28
0.43
ˆ
3,1
ˆ
3,1
2.30
0.50
−1.47
0.07
ˆ
3,2
ˆ
3,2
−2.11
0.36
−2.18
0.24
ˆ
4,1
ˆ
4,1
0.67
0.48
−1.43
0.04
ˆ
4,2
ˆ
4,2
−0.63
0.30
−0.84
0.06
ˆ
5,1
ˆ
5,1
0.54
0.53
−1.91
0.04
ˆ
5,2
ˆ
5,2
−0.74
0.34
−0.35
0.04
ˆ
6,1
−2.09
0.05
ˆ
6,2
−0.43
0.05
ˆ
3
0.94
0.03
et al. (2006) to approximate a diffusion model, although other approaches
might also be feasible and provide a more mechanistic model (e.g., to
model colonization as a function of the number of neighboring routes
where house finches are present).
It should be noted that in this example, distance has been used as a
covariate to model changes in the house finch's range, although other
covariates could be used instead or in addition. Latitude and elevation
might be especially relevant covariates for questions related to changes
in species distributions caused by climate change.
9.6 Study Design
Good-quality data are the key to being able to make robust conclusions. This
is no less the case with occupancy models as in any other area. For the two-
category models, MacKenzie and Royle (2005) and MacKenzie et al. (2006)
