Model group Independent variables
Predator ~ light azimuth + zenith + stage + week + azimuth*zenith + azimuth*stage + zenith*stage + azimuth*week + zenith*week + [bout length] + [diven] + (year) + (birdID) + (TDRlogint)
Prey ~ light zenith + azimuth + azimuth*zenith + week+azimuth*week + zenith*week + [velocity]
Predator ~ prey prey_depth + prey_aggregations + prey_depth*prey_aggregations + [bout length] + [diven] + (year) +(birdID) + (TDRlogint)