Differences in the flight initiation distance near expressways and in open farmland in wintering Common Buzzards (Buteo buteo)

Figures & data

Table I. Factors for analysing effects on Common Buzzard flight initiation distance.

Code	Description
Habitat	habitat (farmland/expressway)
StartDist	starting distance (SD) – distance from where the observer started walking towards the bird and the bird’s position
BuildDist	distance from the hunting site to the nearest building
TreeDist	distance from the hunting site to the nearest tree

Figure 1. Data distribution of flight initiation distance (m) of Common Buzzards Buteo buteo.

Figure 2. Mean number (dots), 95% confidence limits (vertical lines) and kernel distribution (violins) of recorded flight initiation distances in two types of habitats.

Table II. Results of models describing the influence of different factors on Common Buzzard flight initiation distance. Degrees of freedom (df), model log-likelihood (LL), corrected AIC criterion (AIC), difference between the model and the best model in the data set (Δ AIC), and weight for the model (AICwt) are shown.

Model (fixed effects)	df	LL	AIC	Δ AIC	AICwt
Intercept+Habitat+StartDist+BuildDist+TreeDist	6	−1504.11	3020.5	0.00	0.570
Intercept+Habitat+BuildDist+TreeDist	5	−1505.70	3021.6	1.08	0.332
Intercept+Habitat+StartDist+BuildDist	5	−1507.46	3025.2	4.61	0.057

Table III. Estimates of GLM model coefficients for the best model of factors affecting FID.

Parameters	Estimate	Standard Error	t value	P value
Intercept	5.411	0.165	32.782	<0.001
Habitat: expressway	−0.828	0.038	−21.515	<0.001
BuildDist	0.225	0.053	4.218	<0.001
TreeDist	0.073	0.028	2.611	0.010
StartDist	−0.088	0.048	−1.837	0.067

Data availability statement

Dataset supporting reported results can be found at the Mendeley Data Repository: https://doi.org/10.17632/k7jwk6pgpc.1