Effects of age on foraging behavior in two closely related albatross species

Table 2 Effects of age (Age = linear relationship, and Age²= quadratic relationship), sex, stage, species and year on trip characteristics and activity patterns of black-browed and grey-headed breeding at Bird Island, South Georgia. ‘x’ indicates terms retained in the average of the best-supported models for each response variable (full model selection and parameter estimates are listed in Additional file 1: Tables S3 and S4)

Response variable	n	Predictor variables
Response variable	n	Intercept	Age	Age²	Sex	Stage	Species	Year	Age: Sex	Age²: Sex	Age: Stage	Age²: Stage	Age: Species	Age²: Species	Sex: Stage	Sex: Species	Stage: Species
Trip duration (days)	158	x	x	x	x	x	x				x	x	x
Max range from colony (km)	158	x			x	x	x	x								x
Latitude at max range (°)	158	x	x	x	x	x	x				x	x	x		x		x
Landings.hr.⁻¹ in daylight^a	66	x	x		x			x	x
Landings.hr.⁻¹ in darkness^a	64	x						x
Wet bout length in daylight (mins)^a	66	x	x		x
Wet bout length in darkness (mins)^a	64	x						x
Prop daylight wet (%)	130	x					x	x
Prop darkness wet (%)	128	x			x	x	x	x

^a Species was not included in the model for these two metrics as sample size was very small for GHA