Table 2. Statistics for the flying behaviour of northern gannets (Sula bassana).

	Non-GPS birds		Non-GPS birds
	AccBack	AccTail	AccBack+GPStail	Acc+GPStail
Foraging trip duration (h)	26/25/26/26	28/25/21	7.5/7/24/10	26/7/24
Total number of flap/glide cycles	90/75/65/89	97/191/131	98/93/97/106	83/150/126
Flap/glide duration ratio	1.61/3.19/3.38/1.55	1.45/4.31/1.28	2.17/4.86/2.26/1.52	2.23/4.22/1.21
Total time flapping duration	352/440/443/352	353/487/340	392/475/400/345	418/489/331
ODBA(mean ± SD)	0.62±0.46	0.64±0.47	0.68±0.62	0.57±0.51

Statistics calculated for all the 14 adult gannets using data from a 10 minute flight period.

The birds were equipped with a miniature tri-axial accelerometer on their back or tail and with, or without, a dummy-GPS underneath their tail ((Non-GPS birds and GPS birds respectively). Each column displays the data for all the birds of each group, between 3 or 4 individuals.