Friday, January 29, 2010

Seychelles Satellite Pop-up Tags Set New Records

During the 2009 monitoring programme two Pop-up Satellite Archival Tags (PATs) were deployed on whale sharks in Seychelles and we are happy to report that both have detached pretty much on schedule!

The first of these was attached on the afternoon of October 9th to a female shark of 5.5m off Bay Lazare which had been swimming quite happily with the monitoring team for 29 minutes.

Poppy one of very few female whale sharks in 2009, photo Torri Kentner

She was swimming slowly and showed no reaction to tagging. This was the first female shark tagged with a satellite tag in Seychelles and so we were keen to see if she behaved differently to the other sharks previously tagged here. Because she was a girl with a pop-up tag she was immediately named Poppy by the team and has drawn a lot of interest as so few female sharks were found last year.

Poppy being tagged by David, photo Torri Kentner

Poppy's tag came off on January 10th at around 13°S 54°E about 400 kilometres off the East coat of Madagascar well South of Seychelles; this is the second time a Seychelles tag has been recorded from this area.

The start and pop up location for Poppy's tag, red dots show tag drift after release. Map courtesy Maptool at www.seaturtle.org

During the course of the 94 days of deployment Poppy dived to a maximum depth of 1304 metres an new record for the Indian Ocean (the I.O. deepest dive to date was 1286m) where her tag recorded a minimum temperature of just 4.6°C!

The second shark tagged was a large (8.5m) male shark named Chompy who was tagged on the 21st of October off Anse Capucin, South Mahe.

Chompy a large male whale shark missing part of his left gill covers, photo Luke Riley

Chompy had been so named because he was missing the gill cover to the 4th & 5th gill slits on the left side, probably chomped as the result of an argument with a boat propeller.

Chompy with his PAT tag safely attached, photo Ciara McCarten

Chompy's tag came off on the 17th of January at 4.6°S 55.8°E to the East of Mahe and South of Frigate on the Seychelles plateau, although no whale sharks have been seen around Mahe for a while now.

The data from his tag shows that there have been several days during the deployment where depths in excess of 300 metres have been recorded indicating that he had in fact left the Seychelles plateau and returned here again on several occasions.


The start and pop up location for Chompy's tag, blue dots show tag drift after release. Map courtesy Maptool at www.seaturtle.org

The data from these tags has not yet been fully analysed and we are sure they will provide further valuable information on the life of these giant sharks.

1 comment:

Luke Riley said...

Awesome news David. Well done team !