Table 2. Results from a linear mixed model analysis.

Results from a linear mixed model analysis of (A) alert distance and (B) flight-initiation distance (FID) shown by flight-capable Canada geese exposed to vehicle approach, 1 through 4 August 2017, at the NASA Plum Brook Facility in Erie County, OH, USA. Treatments comprised vehicle approach direction (direct or tangential) and exposure level of the companion group (blind or exposed; CGtreat) to the approaching vehicle. Here, we also considered the effect of flushing a bird from a holding cage on escape response.

Effect	Num df	Den df	Chi-Square	P > Chi-square	F	P > F
(A) Alert distance
Flushed	1	73.4	0.03	0.8706	0.03	0.8710
Direction	1	18.1	0.08	0.7766	0.08	0.7799
CGtreat	1	47.9	0.56	0.4533	0.56	0.4569
Direction × CGtreat	1	74.8	0.09	0.7654	0.09	0.7663
(B) Flight-initiation distance
Flushed	1	74.8	0.00	0.9765	0.00	0.9766
Direction	1	28.5	1.02	0.3114	1.02	0.3199
CGtreat	1	62.5	0.09	0.7594	0.09	0.7604
Direction × CGtreat	1	74.2	0.52	0.4703	0.52	0.4725