How we work

Spot6 - Tags

SPOT6 (towed) is the type of tag, together with its predecessor the SPOT5, we have most deployed.

They give us the horizontal (surface), data using the Argos satellite platform. Wet / dry sensors allow the tag to detect when on the surface in order to transmit data.

They also collect time at temperature data that allows us to infer depth using “known” temperature gradients in the oceans. They do not  archive any data. 

Battery life is from 280 - 300 days.

fin-mount

SPOT6 (fin-mount) was first deployed in the 2017 season in Galapagos.

The data collected and transmission mechanism are the same as for the towed SPOT.

As the name suggests they are deployed using a bear claw type hinge attachment and are placed towards the top of the primary dorsal fin. 

They have been deployed successfully with juveniles in other study areas but this is the first deployment with adult females of this size. 

miniPAT

MiniPAT is a pop up archival tag that is designed to track large-scale movements of its host using a combination of Argos and stored data.

Whale sharks, like many fish do not necessarily spend much of their time at or near the surface so the archival data provides the vertical spectrum of their life.

At a pre-programmed time and date the tag releases and after a certain period it begins to transmit the archived data.

The MiniPAT is set to 180-200 days in order to maximise data collection time to battery life.

They may prematurely release if the shark dives beyond their “crush depth” of 1850m.

SPLASH tag

SPLASH tag combines Argos capability for recording and transmitting horizontal movement together with archival data for vertical profiles.

Additionally the tag is equipped with “fastloc” technology that allows GPS location and transmission with minimum surface time.

The enhanced data storage capability together with GPS and Argos position make this tag the preferred option.

At present this is also deployed using a tether of steel cable or “dyneema” cord. As with the SPOT the tether is 140-180cm in length.

fin-cam

Developed by British technical films the camera was deployed successfully a total of three times on whale sharks in the Galapagos during the 2016 field season. Two times on the dorsal fin and once on the left side pectoral fin.

In total about 15 hours of video was captured in 2.7k high definition at 30fps.

The attachment was by fin mount with a temperature sensitive GTR (galvanized times release), which was then further modified for short-term 6-8 hour attachments. Retrieval was by SPOT6 satellite tag and VHF pinger. The satellite tag was for general search area and the VHF pinger for location.

Ultimately we only used the VHF pinger with Yagi antenna as on one occasion the fin cam was spotted near the research vessel floating upside-down and on another it was retrieved from the shark the following day. In open ocean the tag was located at a distance of 12.8nm from the anchorage at Darwin Island almost due west of the research site.