Table 1. Estimates of x (proportion of body mass used for fuel consumption, see Box 1) for different species of migratory birds and a marine migrant (the eel, Anguilla anguilla).

Species	m 0 (kg)	Distance (km)	X (% m h−1)	Source
Blackpoll warbler Dendroica striata	0.011	1300	0.56	[36]
Thrush nightingalea Luscinia luscinia	0.025	-	1.0	[37]
Bar-tailed godwit Limosa lapponica	0.166	11 000	0.42	[6]
Greater knot Calidris tenuirostris	0.143	5 400	0.52	[38]
Red knot Calidis canutus	0.126	4 800	0.77	[32]
Ruddy turnstone Arenaria interpres	0.115	3 700	0.48	[8]
Ruby-throated hummingbird Archilochus colubris	0.0044	1 100	2	[3]
Eel Anguilla anguilla	0.734	5 500	0.0053	[34]

^abased on wind tunnel study.