Tracking sea turtles in Samoa: Lady Vini and Miss Lina

Release of Lady Vini after fitting the radio transmitter.

Movements of Lady Vini

Lady Vini, a nesting hawksbill turtle was tagged and released from Satitoa Aleipata on 06 March 2006. Her name derives from that fact that she was caught on Vini Islands.

Final update, January 2007

In the seven months (228 days) when the satellite tag was transmitting signals, Lady Vini:

• travelled through the EEZs of 7 countries/territories
• travelled a distance of 4,743 km
• spent between 9-85% of her time underwater, with an average of 50%
• has been a living pelagic/oceanic turtle, in contrast to a directed travel from nesting area to benthic foraging area as normally occurs for post-nesting hawksbill and green turtles.

Lady Vini has clearly demonstrated their migratory nature and that turtles are a shared resource. Their conservation/management thus requires regional cooperation.

Update 27 October 2006

Six months at sea is a long time and, as mentioned in an earlier message, surely this turtle has been "living pelagic." In contrast, that is, to a "directed travel" from point A (nesting area) to point B (benthic foraging area) as "normally" occurs for post-nesting hawksbills and green turtles. George Balazs.

Previous Update 18 September 2006

George's latest update: Lady Vini is currently swimming in Tuvalu waters. At this point, we have to consider the possibility that the turtle is living pelagic, and not trying to make a land-fall reef or coastline. For an adult hawksbill, that would indeed be a surprise if true. But that's what science inquiry is for - to ascertain what is happening, what the truth is out there in the far reaches of the sea.

Dr Colin Limpus of Australia responds: This is certainly an interesting turtle and one that is giving new insights into their behaviour. It fits with some of observations we have from longline fishers over here in the SW Pacific of occassional adult-sized hawksbill being caught well out to sea in ~4,000m depth waters.

I satellite-tracked an adult male green turtle ("Dean the Green") that left our inshore coastal sea grass habitat (where we had been recording it for some months) and travelled out into oceanic waters for a month before returning back to our coastal waters. It never made sense at the time for an adult green to spend a month circling around in oceanic waters. However, it did swim over 3 of the 4 seamounts that occurred in the area of its swim.

Perhaps we need to re-examine the possibility that adult Cheloniid turtles may be able to function quite well in oceanic waters -- that they may not necessarily have to occupy coastal habitats. Pam Plotkins studies certainly showed that adult ridleys can function in oceanic waters during the entire period between breeding seasons!

Prior Update 19 July 2006

"Is this lovely turtle playing games with us, swimming back and forth?

"Some of you may have wondered-- Is Lady Vini really alive? or, Has she passed away and her body is floating drifting with the ocean currents?

"Well, let me calm your concern- we have a sensor on all ST-20 transmitters (like Lady Vini'S) that "measures" percent time spent underwater - Lady Vini has spent between 9-85% of its time UW with an average of about 50%.. Numbers continue to indicate that she is definitely not just floating. She's an active swimming and diving sea turtle. Just the way we want her to be," George Balazs writes.

Movements of Miss Lina

Miss Lina, a sub-adult green turtle, was tagged and released from Vaiala on 25 Feb 2006.

Update 19 July 2006

George Balazs: "Miss Lina seems to be doing very well and certainly this is a successful satellite tracking. She seems to have settled in at a specific site at the northwest coast of Upolu."

Related links and information

• YOST sea turtle satellite tracking
• American Samoan turtle tracking
• Seaturtle.org Satellite tracking
• Tags
• SPREP Turtle tags database

Contact: Lui Bell, Marine Species Officer, SPREP: LuiB@sprep.org