A day in the life of a CICI intern is an amazing ride with everyday bringing something new. Some days you might diving on incredible reefs, handling black tip reef sharks, attempting to husk a coconut or playing volleyball with the boys. This is the third time coming back to the Conflict Islands and I’m lucky enough to say I’ve spent the last four weeks with some incredible people. Looking back, I can say 2020 was my favourite trip yet. In fact it was the start of an exciting new adventure, for both the team at CICI and myself, called The Walking Shark Project.
In 2019 my love for the Milne Bay Epaulette Shark was sparked when we spotted one on a night dive while working on the Sharks and Rays Internship. We jumped into the water as the sun was going down and slowly descended down the reef slope toward the drop off. About 10 minutes into the dive I spotted something moving at the edge of my dive lights, so naturally I went to investigate. To my excitement it was a Milne Bay Epaulette, slowly using its pectoral fins to walk over the coral. As the rest of the group started to swim in the opposite direction I flagged down my dive buddies to share the experience and my excitement. The shark was so relaxed and didn’t swim away but just sat with us for a few minutes until we had to leave to catch up with the rest of the group. This was my first experience with a Milne Bay Epaulette shark and it sparked a love and extreme interest in the animal.
After returning to Australia I knew I wanted to learn as much as I could about the species. I spent a while reading as much as I could about it, its genus and other similar shark species and found that there is very limited information regarding the species. The Milne Bay Epaulette shark or Hemiscyllium michaeli, described in 2010, is a small (often less than 85cm long) bottom dwelling shark found predominantly in the Milne Bay Province of Papua New Guinea, however it has also been spotted in the Oro Province. This species of shark is one that can pump water over its gills without swimming and therefore can rest on the sea floor. Currently there is very limited research regarding the species leaving many questions unanswered including their genetic diversity, distribution, habitat preferences, biology, reproduction and diet. The ICUNs Redlist currently classes the species as Near Threatened, however a more in depth assessment needs to be undertaken due to limited data.
This is where the Walking Shark Project comes in. Following my readings into the species I got in contact with CICI to discuss opportunities to study the species and I could not be more thankful to Hayley for encouraging my interest. We talked and decided that there is a large gap in the knowledge of this species so why not try filling some of that gap and try doing a PhD on it. In February 2020 I headed out the Conflict Islands for a third time, this time with the intentions of collecting pilot data to see if the methods I wanted to use would work. Our intentions were to work on a sampling method to collect morphometrics, genetics, sex and distribution data. This would mean a bunch of night diving for the volunteers and staff working on the Shark and Ray internship and a learning curve for all of us.
The first night dive back we took it easy assessing the best spots to try out the methods, and saw three epaulettes that night! Coming back to the boat that night with bioluminescence glittering behind the dinghy, we were all excited for the next night of diving and for our first sampling attempts. The plan was: four divers would descend to search for the sharks with a search time of 50 minutes, if one was found time, depth, temperature, habitat and behaviour would be noted by one diver. At the same time one of the local staff, with more experience handling sharks, would attempt to induce tonic immobility to bring the shark up to the surface for the work up. Another diver would flash a torch at the surface to notify the boat. Two people would be waiting on the boat with a tub and sampling kit to complete the work up. Like many firsts, our first attempt at capture was unsuccessful. However, we found that although these sharks are small, they are very strong and tonic immobility didn’t seem to be an effective method for capture.
The next day, between working on BRUVS (baited remote underwater video systems) and sampling the juvenile black tip reef shark population, we worked on some other capture options. The final plan was to guide the epaulettes into a mesh bag to bring them to the surface, so that night we took out the dinghy to try it out. Sitting on the dinghy waiting to see if the method would work or not was nerve racking but also exciting. After about 15 minutes we spotted the lights underwater flashing, so we moved the dinghy into position to collect the epaulette from the divers and noted our GPS location. It was our first successful capture and we were all so excited and a tad nervous. We placed the epaulette in the tub on the boat with some seawater in it and started the first work up. I held the epaulette while Maisie, one of the volunteers, took measurements and genetic samples. We also took photos of the sides and top of its head to see if we can identify individuals by their markings. Before letting it go, we turned it over to get the sex, this one was a big girl measuring 65cm. She was soon named after Trini, the volunteer who spotted her.
Following our success that night, we continued using this method as often as possible, dependent on weather and other restrictions. Over the following month we sampled approximately every second night, observed 15 individuals, and successfully captured and collected data from 13 individuals. Five of them were sampled in one hour of power! One of which, Stumpy, was missing his second dorsal fin, although he had no apparent scaring suggesting a genetic defect. Our smallest was a 33cm juvenile male and our largest was a 71cm male. We even managed to find one sleeping during the day on our last dive before heading back to Australia! Although our data set is small so far, it’s an incredible start and very exciting for the research this data will contribute to.
I’m happy to announce that data collection on the Milne Bay epaulette will now be a part of future Shark and Ray internships thanks to CICI and Hayleys support. I’m so thankful for all the Shark and Rays team and volunteers that have helped me over the last month on this project and I can’t wait to see what the future will bring for it. Over the upcoming months I’ll be working hard to turn this project into my PhD, and if I’m lucky it will mean the next three years spent working on an animal I love in the most beautiful part of the world.
If you’re interested in joining our work on the Milne Bay Epaulette or just want to learn more about sharks and rays, join up for one of the volunteer programs open for 2021. Or if you just want to follow our progress and keep up to date, check out @the_walking_shark_project on Instagram.