Wednesday 27 August 2014

Preparing the tags...

23:00 August 26, 2014

After a morning of interviews (NewstalkZB; Cook Islands News; Cook Islands TV) and a midday session sighting in of the scope on our pneumatic line thrower (that's how we'll be deploying the tags this year - see the video below!), the team spent the afternoon at the Cook Islands Whale and Wildlife Center.  The Whale and Wildlife Center is one of my favorite places on Rarotonga - I learn something absolutely fascinating every time I go (today I learned that sea turtles slow their heart rates dramatically while diving to feed - this allows them to stay down longer). We were at the center so Nan could give a talk to a group of U.S. study abroad students (IES program) who are at the University of Canterbury this winter semester. Imagine my surprise to hop out of the back of Nan's Whale Research ute (that's the austral word for 'pick-up truck') only to see a couple of the students I was just teaching last week in lecture theaters at UC!

From the Whale and Wildlife Center, it was off to dinner with some of our new friends from the Wildlife Trust's Living Seas project. This was a very special evening - 4 humpbacks, a mother and calf with two male escorts were swimming past just outside the lagoon as we drove up. An awesome start to a fantastic dinner of fish burgers and chips (aka French fries). We were even lucky enough to get a private viewing of a Living Seas documentary on Grey Reef Shark feeding behavior in Coral Canyon, French Polynesia - Simply EPIC! Thanks, Phil!!

Back at HQ, Alex and Frederico got stuck into the task of sterilizing the satellite tags while I looked up the Argos satellite passage times in the South Pacific for the next few months.  We need to program the tags to transmit to the satellites at specified times of the day in order to preserve battery life and maximize data quality/scientific outcomes. Thus, we want to program the tags such that they transmit when there are largest possible number of satellite connections available in the region. We achieve this by picking the times of the day when there are 2-3 satellites in transmission range. There are now only 6 Argos satellites remaining and their orbital periods are spread across the 24-hour day. Apparently all the Argos satellites are past their initial life expectancies, so there is significant motivation to get sat track data while the satellites are still operational!

These are crucially important aspects of tagging that I hadn't fully appreciated - this is the first time Alex and I have been together on a tagging trip despite our 7-year international collaborations together (the financial pressures on our research are not insignificant). Ultimately, Alex and I programmed 3 of the 10 tags for possible deployment tomorrow AM.  We chose a daily 3 hours off - 8 hours on - 4 hours off - 7 hours on - 2 hours off duty cycle for these three tags. This will maximize the potential for gaining the highest quality data, while also capturing the dawn and dusk periods - natural time stamps that animals might use as part of their navigational decision-making process.

So we're off to tag in the AM all going well! I will send along an update as soon as I can...

Thanks for following along, folks!


1 comment:

  1. Good luck out there, Travis! - Scott Soutter