Far From Land The Mysterious Lives of Seabirds

MAP 1. A map to show how, compared with immatures, breeding Northern Gannets tend to travel over
a smaller area and do not visit other gannet colonies. Study based on GPS satellite- tracking of immature
Northern Gannets caught at Grassholm, Wales. Grassholm is indicated by the black star while circles
indicate all other gannet colonies in the United Kingdom, Ireland and France. Maps (a– e) show at- sea
movements and presumed prospecting behaviour of five individual immature gannets caught at Grass-
holm 10 July and tracked until 3 August 2009. Different coloured tracks represent repeat trips after
returning to Grassholm, filled coloured circles represent visits to different gannet colonies, and hatched
filled circles represent birds within 10 km of another colony. Map (f) shows at- sea movements of 25
individual adult gannets (including 5 repeat tracks) breeding at Grassholm during June– July 2006. See
page 46. Map reproduced, with permission of Springer, from the work cited in Note 4, Chapter 3.

Immature 2

N

b.

Track 1

Track 2

n = 380 fixes

10–28 July 2009

a. Immature 1

Track 1

n = 29 fixes

10–14 July 2009

d. Immature 4

Track 1

Track 2

Track 3

Track 4

n = 162 fixes

10–26 July 2009

c. Immature 3

Track 1

Track 2

Track 3

Track 4

Track 5

n = 195 fixes

10–29 July 2009

f. Breeders

GPS tracks

n = 26 individuals

16–17 June 2006

12–17 July 2005

e. Immature 5

Track 1

Track 2

n = 336 fixes

10 July–4 Aug. 2009

0125250

km