After the Christmas break I headed over to Palau to meet up with Steve Lindfield, 2008 AU Rolex Scholar. Since Steve finished his scholarship, he has completed his PhD and is now living and working in Palau!
Steve showed me a lot of the work he has been involved with in Palau on small-scale fisheries and other research projects. He has been using stereo-video techniques while diving to aid a lot of his research, and we got to play around with some of the equipment! Basically – the stereo video set up is really useful for measuring the size of fish in the water. It consists of two identical cameras mounted on a platform at a set distance apart. Because the cameras are identical and are recording with the same amount of pixels – you can use computer software to determine the lengths of recorded animals.
There is a bit of work that needs to be done beforehand though! We spent about half the day in the pool calibrating some of these systems so they were ready for use. To calibrate the cameras – you need a ‘calibration cube’, and lucky for us, Steve had one! The cube is a structure that has markings at set distances apart along all axes. We started recording with both cameras on the platform, and then moved the cube in a bunch of directions. Later, Steve used the software to complete the calibration. Now we can use them to measure the size of fish (including sharks and mantas), and the program can even tell us how far away the animals are from the cameras!
While in Palau, Steve showed me what this part of the world has to offer for diving. Sams tours were generous and showed me around the Rock Islands, and I snuck some incredible diving in; spotting an abundance of turtles, schooling fish, healthy reefs and tons of sharks! Coral Reef Research Foundation, where Steve works, also allowed me to come diving one morning for the bumphead parrotfish spawning, which was absolutely incredible.
Next, it was time for Steve and I to head to Yap for Manta Mania, and Manta Ray Bay Resort & Yap Divers. This was the second year for manta mania, a weeklong diving event that Steve and I were invited to present at. The aim of the citizen science week is to educate divers and those interested in the marine environment about the local population of mantas in Yap, and also about different areas of marine science, and how we conduct it! We had Guy Stevens from the Manta Trust to talk about manta biology and his research in the Maldives, Steve was talking about his research with Stereo-Video, and I talked about sharks, and how we research them.
It was a great week with a great turn out of divers from around the world. Of course, being manta themed – we had some epic manta diving as well at one of the shallow cleaning stations. We ended up spotting about half of the documented population of mantas in this area over the week we were there. It was also a chance for us to use the stereo-video equipment to get some accurate length measurements to further document the population structure in these waters.
I’m keeping on with this manta theme, as I head to Pohnpei next with Julie Hartup, the organiser of Manta Mania and founder of the Micronesia Conservation Coalition. Stay tuned!
