Individual consistency in migration strategies of a tropical seabird, the Round Island petrel

Table 2 Results of generalised linear models to investigate (a) the similarity of petrel whole migrations within- and between-individuals and (b) the spatiotemporal similarity of within-individual petrel migrations when split into six equal stages, using earth mover’s distance (EMD) ‘effort’ values

Variable	Estimate ± SE	t value	p value
(a) Whole migration EMD comparisons (R² = 0.020)
(Intercept)	1862.17 ± 19.17	97.14	< 0.001
1 (Same individual)	− 1287.08 ± 39.38	− 32.69	< 0.001
Difference in departure	2.15 ± 0.20	10.60	< 0.001
(b) Six stage EMD comparisons (R² = 0.061)
(Intercept)	500.51 ± 62.80	8.0	< 0.001
Stage*
Stage 1	234.33 ± 90.04	2.6	0.01
Stage 2	359.11 ± 98.47	3.6	< 0.001
Stage 3	398.67 ± 101.20	3.9	< 0.001
Stage 4	355.13 ± 98.20	3.6	< 0.001
Stage 5	448.60 ± 104.67	4.3	< 0.001
Stage 6	543.29 ± 111.35	4.9	< 0.001
Difference in departure	3.94 ± 0.84	4.7	< 0.001

Minimum adequate models are shown and categorical variables are being compared to reference levels; for the ‘same individual’ binary variable, this is 0 (different individuals), and for ‘stage’, this is the whole migration. Significant effects (p < 0.05) are highlighted in bold
*The full pairwise comparisons for the categorical variable ‘stage’ can be found in Table S4

ISSN: 2051-3933