Short- and long-distance avian migrants differ in exercise endurance but not aerobic capacity

Table 1 Summary statistics of linear regression models testing for differences in body condition parameters

Factors	Pectoral muscle score (ranked)		Fat score (ranked)		Hb
Factors	t	p	t	p	t	p
Intercept	17.76	< 0.001	17.00	< 0.001	70.36	< 0.001
migration strategy	0.73	0.47	0.04	0.97	−1.89	0.06
w/i SD	2.44	0.02*	0.82	0.42	−2.85	0.004*
w/i LD	−0.29	0.77	0.25	0.81	1.78	0.08
Sex	1.95	0.05*	−0.05	0.96	0.18	0.85
Infection	−0.62	0.54	−2.03	0.04	−2.50	0.01*
F (df)	2.84 (5248)	0.02*	1.15 (5248)	0.33	5.18 (5244)	< 0.001*

Legend: Body condition estimates are pectoral muscle score, fat score, and haemoglobin concentration (Hb, mg ml⁻¹). Hb refers to the haemoglobin content of whole blood. Migration strategy provides the comparison between long-distance (LD) and short-distance migration (SD), whereas w/i SD and w/i LD give the comparisons between species within each migration strategy. The factors sex and infection test for differences between males and females, and between non-infected and haemosporidian-infected birds. F, df, t and p-values are the accompanying statistical model parameters, * gives indicates statistically significant differences at p ≤ 0.05 (for details see Methods)