Table 2.

Top candidate model set (within 2 AICc of the best-performing model) for the traits that best predicted return rates in adult tree swallows

Model ID	K	AICc	Effects in the model	ΔAICc
1	3	50.98	Sex + OxsPC1	0.00
2	4	52.44	Sex + OxsPC1 + teloPC1	1.46
3	4	52.49	Sex + OxsPC1 + cort	1.51
4	4	52.74	Sex + OxsPC1 + cond	1.76

K denotes the number of parameters in the model, AICc refers to the second order Akaike Information Criterion, ΔAICc shows the difference between the AICc value of the actual model and the best model in the model set. Variable abbreviations: OxsPC1 = principle component of oxidative stress, teloPC1 = principle component of telomere lengths, cort = corticosterone levels, cond = body condition.