Results
Altogether, the motion sensor triggered cameras captured 24,596 and
45,387 images and the time lapse cameras 134,979 and 142,506 images in
2020 and 2021, respectively.
The best fitting count model had a negative Binomial distribution (NB1
parameterization) and it accounted for zero-inflation (zero-inflation p
<0.001, Table 1). It included the fixed factors ‘trigger type’
and ‘year’ without their interaction and the random intercept of ‘site’
(random effect variance (σ2) of 0.9062 and standard
deviation (SD) of 0.952). Taiga bean goose count was significantly
higher in 2021 compared to 2020 (p <0.001, Fig. 3), however,
the camera trigger type had no significant effect on the number of geese
(p = 0.129).
As the AIC values were within <2 of each other, the best
fitting logistic model on goose capture probability was selected based
on parsimony and it included the fixed terms ‘trigger type’, ‘year’ and
‘effort’ without interactions and the random intercept of ‘site’ (random
effect σ2 = 0.6215 and SD = 0.7883, Table 1). The
capture probability increased significantly with increasing camera
effort (p <0.001) and was significantly higher in the year
2021 (p <0.001) and marginally significantly higher (p =
0.049) with game cameras set to time lapse (Fig. 4).