Sunday, April 17, 2016

Guadeloupe Sperm Whales Expedition - 2016

This is the third FIU-SPAWRAC expedition to study sperm whales and other deep-diving whales and dolphins off Guadelupe Island in the eastern Caribbean Sea.  I was able to join the expedition – led by lab researcher Dr. Jeremy Kiska - for 4 days, but the team got started a few days before my arrival and will stay on until the 18th of April.  Below is the account from the days I was there.  For more information on the project, check out our 2014 blog posts, and stay tuned for exciting developments.  We are working on several scientific papers and also have been working with Patrick Greene (SymbioStudios) to produce video projects for teachers to use in K-12 classrooms! We’ll also be sending out tweet updates (@symbiostudios, @mikeheithaus) and we will update the blog once the expedition gets wrapped up!

-Mike

Day 1 – April 10, 2016

Patrick an I arrived yesterday evening and joined the crew onboad our mothership Saravi III.  So far the trip has been a success!  The team spent the first three days using towed sonar to map the distribution of potential sperm whale prey from nearshore waters to 1500m deep and around a seamount that has been a sperm whale hotspot in the past.  They also managed to encounter a number of sperm whales – including a group being harassed by false killer whales – and Mehdi Bahktiari  (the designer of the whale cameras we are using) deployed the first camera of the year.  Unfortunately, the suction cup worked too well, and the camera has not popped off yet and is missing in action.  The cameras have built-in release mechanisms so it will come off – hopefully before the whale swims far beyond the range of our transmitters we use to pick them up (about 20 miles).

We got underway at 530 and had time to get our gear together while we steamed to the learest gas station (about 2 hours away). Once we had filled up,  we headed straight offshore to 1000m of water to listen for sperm whales.  After the challenges of finding whales during my last trip (2014), I have to say it was very exciting to hear that there were sperm whales in the area the second the hydrophone hit the water.  Because the hydrophone is directional, we knew which way to head and it wasn’t long before we were in the small boat getting ready to deploy a camera!

Putting a camera on a sperm whale isn’t particularly easy.  First, you have to find and stay with the whales, which can be challenging when they regularly dive for more than 25 minutes.  A whale can travel a long way in that amount of time and often the boat is too far away to approach the whales before they dive again.  That is what happened on our first try to get close.  It looked like the same thing would happen on the next surfacing of the whales, but we headed towards them slowly just to try to get an idea of the direction they were heading.  We got lucky.  The whales stayed at the surface for a long time and lab scientist Kirk Gastrich’s slow approach got us close as the whales were taking their last breaths before diving.  We thought we had just missed the group when one last whale popped up for two last breaths close to the boat.  We had one change, and we were able to deploy the camera.

Unfortunately, the deployment didn’t last super long.  After about 15 minutes, the camera was up.  After viewing the video we found out why – a young whale kept bumping into the whale with the camera, several times knocking the camera.  Amazingly, the suction cup held up to three pretty major hits, but on the forth it came off.  Although we didn’t get the data we wanted it was good to see the camera can take so much abuse, and there was a great sequence of the adult whale producing a coda (a train of clicks to a specific rhythm) and the smaller whale answering.  We also saw that our new headlight system will be perfect for getting images from the darkness of the deepsea without disturbing the whales!

Deploying an Exeye camera on a sperm whale

View down the body of a whale wearing the camera




Day 2 – April 11, 2016

Today was one of those simply amazing days!  We got going early in spite of rain showers and headed straight offshore.  We were rewarded with an encounter with Fraser’s dolphins shortly after leaving the harbor at Malendure.  It didn’t last long, which is typical of Fraser’s.  A group split off and came to ride the bow briefly then shot off to continue on their way.   Like yesterday, we heard sperm whales as soon as the hydrophone hit the water and we were off in search of them.  It wasn’t long before we saw the characteristic blows off in the distance!  Unfortunately, the conditions weren’t great at the time and even though we had the tagging boat, Jeremy in the filming boat, and Saravi III we had a hard time staying with a group.  Luckily there were whales all over – individuals and small groups could be seen in the distance, all seeming to head north.  After a couple hours we finally had our chance and got close to a group.  Unfortunately, we weren’t quite close enough and I wasn’t able to get the camera to stick to the whale!  It can actually be hard to get the suction cup to stick because there are only a few parts of the body that aren’t too wrinkly (which keeps the cup from sticking) and sperm whales shed their skin a lot.  If the cup hits a spot where the whale is shedding, the cup can’t stick.

We weren’t thwarted by the miss and stuck with our efforts.  As we went through the day trying to get close to the whales we encountered many other species (7 in total).  Jeremy saw dwarf sperm whales – which are small and shy – and we heard humpback whales while trying to figure out which direction the sperm whales were going.   A group of spotted dolphins came to ride the bow while we were trying to get close to a sperm whale (not helping at all), and we saw a Gervais beaked whale (a deep-diving toothed whale that is not often seen) as well. 

Spotted dolphin
 

Eventually we got our chance.  The winds had died down and a juvenile whale was lingering at the surface (and showing some interest in the boat).  It was just the opportunity we needed and the camera was deployed…for three minutes.  A look at the video showed that the lip of the cup was on a spot where the whale was sloughing skin.  With about 10 whales spread around the boat we made a quick trip to Saravi III to get ready to deploy again.  On the way a group of rough-toothed dolphins showed up, but we didn’t have time to spend with them and headed back to the whales.

Over the course of the next hour we spent time trying to deploy.  The whales were socializing with each other (especially some juveniles) and were very relaxed so we could take our time, waiting for the perfect opportunity to deploy without disturbing the whales.  My previous three deployments had been on the side of whales’ dorsal fins, so this time I tried for the smooth area on the back between the blowhole and dorsal fin.  A fortuitously timed swell and Kirk’s expert driving gave me the perfect opportunity.  The camera was deployed, and we started tracking the group.  It was amazing to watch the animals for so long without them worried about our presence! 
Sperm whale group

Sperm whale with camera
Whale-cam view of two other sperm whales


It turns out this camera was stuck really well.  In fact, as the sun set it was still on the whale after more than four hours.  With the swell building and multiple boats that need to be towed by Saravi III we had to leave the area far offshore where the whales were to spend time in shallower waters near the coast.  We can’t go into the harbor at dark so we will be on one hour watches tonight as we patrol the shallows listening for the camera to pop off…I get the 2am shift!


Day 3 – April 12, 2016

We started the day very early since we were already offshore when the sun rose.  I have to say that I really enjoyed my 2am watch with the amazing stars and calm seas. Conditions this morning were not ideal, but we headed north to try to listen for the missing camera.  We quickly found sperm whales, and launched both small boats to work with them in hopes of getting biopsy samples. While the small boats tried to find the whales again in the swell and chop, the Saravi III broke off and headed 12 miles north to listen for the VHF signal. Unfortunately, the wind was already picking up and we were unable to get close enough to the whales for a sample.  The rest of the day was spent searching for (and not finding any) sperm whales, dodging nasty rain squalls, and bailing a leaking filming boat. We did have a nice brief encounter with spotted dolphins at least!  Tomorrow we will continue our quest to find the camera – Mehdi thinks he heard it faintly to the north. 

Day 4 – April 13, 2016

It was a nice day to be on the water, with flat calm seas greeting us early in the morning.  But the sperm whales were not cooperating.  The hydrophone produced no sign of sperm whales when Saravi III got out to sea.  It wasn’t a good sign since sound travels so far.  We did run into a large group of pilot whales though.  The group of maybe 100 animals was spread out over a wide area and were resting and traveling very slowly.  We spent a while with them, but the Saravi III and our inflatable tagging boat broke off quickly to go look for sperm whales in an attempt to get one more camera deployed before Patrick and I had to leave and to get Jeremy started with biopsy sampling this year.  Jeremy and I were on the tagging boat and had an amazing encounter with Fraser’s dolphins. We found maybe 400-500 animals in four tight groups leaping to the south, then changing direction before moving south again.  Jeremy had never seen anything like it.  We didn’t linger though – there were sperm whales to find. 

A large group of Fraser's dolphins on the move


The filming boat stayed with the pilot whales for quite a while before they saw a large pilot whale in deeper water come to the surface and violently tail-slap the surface.  Almost immediately, the sleepy pilot whales they had been with woke up and started swimming quickly in the direction of the tail-slaps and deeper water. 

Unfortunately, despite good conditions and a very determined effort we didn’t find any other animals the rest of the day.  Whale watching boats reported a similar experience – no sperm whales to be found on the west coast of Guadeloupe today.  It is interesting that we saw a big group of pilot whales today and no sperm whales.  We had a similar experience in 2014.  When we saw pilot whales, there were no sperm whales and vice versa.  Pilot whales are known to harass sperm whales until they regurgitate – then the pilot whales eat what comes up – so maybe the sperm whales have moved somewhere else temporarily. 

When the day was over it was bittersweet to be packing up.  It was an amazing trip, and I am sure there will be more great work in the next few days before the project wraps up.  After that it is time to analyze the data we have collected, finish the films and classroom videos, and plan the next steps in the research!