Turtle cam

With the Reunion Island trip finished (for me at least), its time to turn the blog over to a few dispatches from Shark Bay, Western Australia!  If you want to learn more about the Shark Bay project in general, we have a ton of information at www.sberp.org.  But, for the latest information, we'll be putting it here on the blog!

I'll now turn it over to Postdoctoral Scientist Dr. Jordy Thomson...

Mike

Introducing turtle-cam!

In late 2011 and 2012, I traveled to Shark Bay with a team of volunteer assistants to study the underwater habits of green and loggerhead sea turtles. We were interested in learning about their diets in hopes of better understanding the roles that these charismatic critters play in Shark Bay’s iconic seagrass ecosystem. The only problem is that turtles in Shark Bay are really skittish (I would be too considering the size of some of the sharks down there) and can spend more than 95% of their time submerged, so observing them in the wild is really difficult. Our solution? To temporarily attach a video camera to their shell to record their behaviour for us.

Here’s how it works. First, we catch a turtle by jumping off the boat and swimming it to the surface. Once the turtle is on board, we attach a short-term data-logging tag that includes a high-definition video camera, along with water temperature and depth sensors, to record its behavior. The tag is designed to stay attached to the turtle for 24-48 hours, during which it can record up to 4 hours of video, before it pops off and floats to the surface. Once at the surface, the tag’s radio beacon allows us to track it down, retrieve it and download the data.

Two of our volunteer field assistants, Fanny Vessaz and Tyler Roberts, about to release a green turtle with a video data-logging tag.

A screen capture of the very first camera deployment on a loggerhead turtle from October, 2011. Shortly after release, this turtle went back to doing what it does best… chomping on invertebrates like this large shell embedded in the sand.

One of our tags floating at the surface after releasing from a turtle (on a nice day, it’s not a bad place to spend some time on the water!).

The two trips were incredibly successful… we deployed cameras on 118 turtles, didn’t lose any tags and recorded nearly 400 hours of video footage! Thanks to the persistence and patience of our volunteers, we’ve now transcribed all of the footage and logged every time a turtle fed, interacted with another turtle or did pretty much anything else that was interesting from a scientific perspective. Over the next few posts, I’ll put up some screen caps from the footage to show some of the highlights and describe how we are using the video data to better understand marine turtle ecology and document some troubling changes in the Shark Bay ecosystem.

Jordy

Well,  I was hoping that this post was going to be able to detail the amazing results of hours of footage from the back of a bull shark, or even a tiger shark.  But, things didn't quite go as planned.  We spent days and nights fishing and didn't manage to catch the bull sharks that were the target for our research.  We did see another beautiful tiger shark but the weather conspired against us so we didn't get a track in.  Jeremy and I have no had to wrap up our time on Reunion, but the rest of the team has two camera units and is ready to go as soon as the sharks reappear!  I can't wait to see what they get.

For the blog, we'll soon have updates from Shark Bay, Australia, Tanzania, the Everglades, and other exciting projects around the world!

Mike

Last night was full of excitement as we finally got out on the water to fish!  Jeremy and I had two cameras ready to deploy and headed out onto the (relatively) flat water ready to track a bull shark through the night!   Being out on the water at night is always exhilarating, but this was truly spectacular!

The first 50 hooks passed with no sharks and so did the first half of the second longline set.  We headed off to test the range of the VHF transmitter on the camera we were hoping to deploy and managed to get at least 5km.  That makes me feel a bit better that we will actually get the systems back!!  While we were doing the test we got a call that we had a tiger shark.

The sharks here are big.  The bull sharks in this part of the world grow a meter (more than three feet) longer than those off the coast of Florida.  The tiger sharks they catch are big too – the one we had was almost 3.9m!  That is around 13’!     Because we are focusing on bull sharks (at least for now) we tagged the tiger and let it go, hoping that we would catch a bull shark later in the night.

We didn’t have any luck, though, except for a guitarfish (which I was excited to see).  With no bull sharks, the fisherman working with us headed back to port to resupply and rest.  We head back out to try again before dawn tomorrow! 

This is a guitarfish similar to the one we caught last night.  In this picture Derek Burkholder and I are getting ready to tag this animal caught in Shark Bay, Australia.  Guitarfish are a type of ray.

We are in business now!  The lines are in the water, the tracking devices and cameras are ready, and we are on standby to head out as soon as they start pulling the line!  Hopefully we will be tracking a big bull shark soon and can get the project into full swing!  Updates might be a while coming if all goes as planned!

Mike

Well, we hit a few bumps in the road and haven't gotten out on the water yet.  But, it looks like we have all the issues resolved and we will be heading out this evening to start fishing!  We used the time on shore to figure out how long the dissolving links that release the camera will last.  Turns out it is a lot longer than we thought so we'll file them down!   We are going to aim for a shorter deployment first - maybe 8-10 hours - before we try for a long one.  I can't wait to see what we learn!

Jeremy and I got a few minutes to drive up into the mountains of Reunion (the pictures below are from the top to the bay where we will be working tonight).  The slopes are so steep that the habitats change very quickly.  We are on the west coast, which is drier, so it is very dry where we are staying.  As you move up the mountain you eventually hit rainforest and then, above the clouds, small trees and bushes growing on rock and lava!

We may be out of touch for a few days on the water...hopefully we will have interesting things to share soon!

Mike

Today was a big day.  We started the day with a few media interviews and then a talk at Université de la Réunion. We got to meet more of the team that will be working with us on the shark mission that starts in the middle of the night tomorrow!  It is a great group of people!

After the talk, we got on the water for the first time to test the flotation of the cameras and to see how far away the VHF transmitter will work.  The VHF is what we use to find the camera after it releases from the shark and floats to the surface of the water.  The range was fine, but it will be a challenge to track the cameras down with the big current and huge swells here at Reunion!

Once we retrieved the camera, Jeremy and I gave a public talk.  I gave it in English, Jeremy in French.  Boy, I wish I spoke French!  It was a great crowd with lots of questions, and there were some very interesting insights from folks who have been living and diving around the island for decades.  The folks here on Reunion are fantastic.  Despite me n,ot being able to speak the language, everybody has been very welcoming!

Tomorrow, Jeremy and I have a couple hours to go to see some more of the island before we load the boat.  Hopefully, I will be able to post some pictures from around Reunion before we head out.

Mike

We arrived on La Reunion today after a seriously long trip!  We got a chance to meet up with some of our fantastic local collaborators today, Pascale Chabanet and Marc Soria, and had a quick look around a small part of the island!  The water and the mountains are stunning!  I will drag my camera out to take some pictures to share tomorrow.  We also made a quick visit to the fantastic Aquarium de la Reunion that features local habitats and species.  After that, we got settled in for our couple of days on land before the expedition kicks off!  That meant time to (finally) have a shower, check in with home, and start assembling the gear.  Luckily we all made it safe and sound.  We can't wait to work with the animals!  

Dr. Jeremy Kiszka - back on Reunion Island and trying to set up the time depth recorders...so far so good

Mike setting up one of the new Mehdi-cams.  We'll go out on the water tomorrow to see how far away we can detect it.

Welcome to the Heithaus Lab blog!  We've decided to get this going so we can share some of our adventures and cool findings with anybody who wants to follow along.  From our long-term studies in Shark Bay, Western Australia and  the Florida Coastal Everglades to newer studies around the world, we have the privilege to work with amazing species in awe-inspiring places and alongside great people.

At the Heithaus lab blog we'll keep up-to-date entries from ongoing field trips and also highlight some of our previous work. From time-to-time I'll also have the opportunity to talk about the amazing scientists I get to work with in filming video projects for elementary, middle, and high school students.  We hope that you enjoy the blog (and appreciate feedback)!  

For our first blog-adventure, Postdoctoral Scientist Dr. Jeremy Kiska and I will be keeping you up-to-date as we travel to La Reunion - an island off the east coast of Madagascar - to work on bull and tiger sharks.   We will be joining colleagues and bringing the latest animal-borne video technology to study the behavior and ecology of these large sharks in a coral reef ecosystem - from their perspective!

We leave on the 7th of May, so check back for updates!  

To get to know the lab better, you can "meet" everybody here. Please pardon the dust around the lab website - we are working on overhauling it!

Thanks for tuning in!

Mike

A few pictures for fun...

I caught this loggerhead turtle in Shark Bay as part of our ongoing research. Many of the loggerhead turtles in Shark Bay, especially males, are missing pieces of their flippers or shells from tiger shark bites.  

Attaching a satellite tag to a tiger shark with lab alum and good friend Dr. Derek Burkholder.

Linda Heithaus and Patrick Greene while filming math and science videos for K-12 students.