Statistical Analyses:
Statistical analyses were performed using R, version 3.6.3 (Team, 2013).
The 3D energy metrics were treated as continuous variables and were
log-transformed so that residuals fitted a normal distribution. The
energy of the nest and null sites were compared at each spatial scale
with the lme4 package using linear mixed models derived from the
following formula:
lmer (log (Energy) ~
poly(Scale,2)*ROI+(1|Site)+(1|ScanID)
+(1|NestID) ) , where ROI specifies nest vs null measurement,
ScanID specifies the label for the individuals can and NestID is the
shared ID for the nest and its corresponding null.
The influence of 3D energy and habitat type on visibility was also
assessed using linear mixed models, while visibility’s effect on
predation was analysed using generalised mixed models with predation as
a binary (yes/no) variable. We also compared the effect of broad scale
(agri-environment and arable)) and fine-scale (wet grassland, gravel,
crop, fallow, cattle-grazed and sheep-grazed) on 3D energy using Tukey’s
post-hoc tests.