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On 9 January 2004, a juvenile hawksbill turtle was captured on intertidal seagrass and algal flats of Cocos (Keeling) Islands, Indian Ocean (1100 km from Indonesia, 2200 km from Western Australia and 1000 km from the nearest landmass of Christmas Island; Figure 1). The Cocos (Keeling) Islands sit atop two atolls, with the southern atoll consisting of 25 islands arranged in a horseshoe shape and the northern atoll consisting of one island. Both atolls are surrounded by water of up to 6000m deep. A satellite transmitter (Sirtrack Pty Ltd) operating on the ARGOS system was attached to the carapace of the hawksbill turtle using a combination of epoxy (Mitchell 1998) and fiberglass (polyester resin and fiberglass cloth; Balazs et al. 1996). The online data collation and data filtering resource of the Satellite Tracking Analysis Tool (STAT; Coyne & Godley 2005) was used for data manipulation. Only location classes LC 3, 2 and 1 of the ARGOS system were used to plot the movements. This turtle measured 63.3 cm CCL and weighed 24.0 kg. It was first captured on 8 February 2002 on the same seagrass flats within one kilometer of the subsequent capture, then measuring 56.5 cm CCL and weighing 16.0 kg. It had been at large for 700 days and had grown at a rate of 3.5 cm.yr^-1 and 4.2 kg.yr^-1.

After this hawksbill was released it remained in the lagoon on the southern atoll of Cocos (Keeling) Islands for 29 days. On 7 February 2004 a good quality reading was recorded outside the lagoon and from this location the turtle moved away from the Cocos (Keeling) Islands and headed south west into water depths of over 5000 m. It reached the Muirfield Seamount on the morning of 10 February 2004 but did not stop. The Muirfield Seamount is located 130 km south west of the Cocos (Keeling) Islands and rises up to 18 m below the surface. It is the only other shallow water habitat in the vicinity of Cocos (Keeling) Islands. The transmitter gave its final location on the evening of the 28 February 2004, a total of 1070 km from the Cocos (Keeling) Islands, with the turtle having traveled at a mean speed of 2.03 km/h (range 0.56-4.23, sd= 0.69, n=74). The transmitter may have stopped transmitting for several reasons including; transmitter malfunction, transmitter detachment or the turtle was predated upon.

Numerous recaptures of hawksbill turtles (including multiple recaptures) between years indicate at least some individuals from these islands show strong site fidelity to localized areas. The movements of the turtle tagged at Cocos (Keeling) Islands indicate that this turtle was either heading to another benthic foraging area or foraging on the surface of the open ocean. The next closest foraging area west of Cocos (Keeling) Islands is the shallow waters of the Chagos Archipelago at a distance of over 2600 km from the Cocos (Keeling) Islands. This observation presents an interesting insight into the behavior of benthic foraging hawksbill turtles. One long distance movement of a juvenile hawksbill turtle (74 cm SCL) is reported from the Atlantic. This turtle traveled over 3500 km from Brazil to Senegal in 1990 (Marcovaldi & Filippini 2001).

Acknowledgements: We would like to thank the Parks Australia North staff, Wendy Murray, Ismail Macrae, Robert Thorn and Nordianna Hajat, at Cocos (Keeling) Islands for their help in the field. Also thanks to Stephen Lane, of HoverCocos for financial support for this tracking work. The authors wish to acknowledge use of the Maptool program for analysis and graphics in this paper (Information is available at www.seaturtle.org).

Figure 1. The track of the juvenile hawksbill turtle.

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