Our World – Underwater Scholarship Society in North America

I’ve only been back from South Africa for a couple of days and I’m already on my way to the airport for a month in the Brazilian Amazon! Stay tuned for updates from Manaus as I spend my time in the field studying piranhas!

My first chance to actually dive in South Africa outside of a cage came just a day after leaving Marine Dynamics!  After leaving Gansbaai I set out to meet up with Steven Benjamin of Animal Ocean for a couple of days in the water and under the surface.  Steve was nice enough to let me stay at his house and was determined to get me in the water no matter what!

He succeeded–  I spent my next few days diving with Cape Fur Seals, Sevengill Cow Sharks, and an American shipwreck the Bos 400.  Steve definitely made my first impression of South African diving a good one.  Next time I will plan more time!  A short video of my dives to come!  Now off to Durban!

I’ve been in South Africa for a few weeks and I love it here!  My first stop upon arriving was Gansbaai/Kleinbaai to visit the people of Marine Dynamics and the Dyer Island Conservation Trust.  Having put white sharks on the top of my priority list I was pretty excited to finally see one for myself.

In total I spent just under two weeks with Marine Dynamics and was out on their shark cage diving boat, Slashfin, almost everyday!  I learned a lot about white sharks and all of the projects associated with the Dyer Island Conservation Trust during my stay.  It’s an amazing organization and one that can use as many volunteers as possible, check them out at www.dict.org.za.

My time in Kleinbaai was an awesome experience and one I will never forget!

After finishing my research cruise to the Northwestern Hawaiian Islands I quickly found myself on a flight to Kailua-Kona on the Big Island to help out on a National Geographic TV shoot!  The project was a huge NatGeo production exploring the Big Island from the top of the volcanoes all the way to the deep sea and was shot completely in 3D.  I had a blast being around large 3D cameras for the first time and getting to know Evan Kovacs (amazing underwater 3D filmmaker) of the Woods Hole Oceanographic Institute Advanced Imaging and Visualization Laboratory.  I even got to meet and hang out with the famed underwater explorer Bob Ballard!  All in all it was a great experience working with old friends and new friends.

(Note: This is the first of 2 posts about the NW Hawaiian Islands research cruise. If they are posted in the wrong order, please read this one first.)

After narrowly missing Hurricane Irene in the Bahamas, I managed to make it in time to Hawaii to push off on a research cruise with the National Oceanic and Atmospheric Administration aboard the R/V Hi’ialakai to the Northwestern Hawaiian Islands.  The mission of the research cruise was to study deep coral reef sites with an emphasis on deep reef fish through the use of open-circuit trimix technical diving.

I was extremely excited to get back to Hawaii after not having been “home” since the start of my scholarship year in April.  I was also pretty amped about the fact that the cruise was filled with an all-star cast of researchers and the opportunity to practice my trimix technical diving skills in a research setting.  The ship pushed off from Pearl Harbor August 29^th and started steaming up the Hawaiian Island chain.  Our cruise schedule was Nihoa, French Frigate Shoals, Gardner Pinnacles, Lisianski atoll, and Pearl and Hermes Reef with a stop at Ni’ihau on the return.  Unfortunately due to an unexpected incident we were unable continue with trimix diving and the Chief Scientist had to quickly change plans and adjust the cruise from a deep reef cruise to a semi-deep reef cruise using conventional scuba.  Consequently, my primary purpose switched from technical diving to assisting my former boss and advisor, Carl Meyer, with apex predator research tagging Giant Trevally (Ulua) and Galapagos sharks.

(Check back soon for a blog about tagging apex predators!!!)

After successfully deploying all of our tags, swapping out underwater acoustic receivers, and getting a dive day with Kelly Gleason on the Two Brother’s shipwreck the cruise came to an end before it felt like we had even gotten started.  I had an amazing trip, met top-notch researchers (Rich Pyle, Randy Kosaki, Carl Meyer, Kelly Gleason, and Greg McFall just to name a few!!!), made lifelong friends, and learned a lot!  I will remember the random art hours and evening jam sessions on the bow, as much I will the research and diving.  There is more to research cruises than science!!

Day two at Pearl and Hermes Atoll marked the northernmost point of this expedition and was the first opportunity to catch and tag some of Papahanaumokuakea Monument’s charismatic reef predators.   The day was a mix of bottom-set long-line deployments, deep hand lining, and surface trolling with the aim of tagging Ulua (Giant Trevally) and Galapagos Sharks.  Our surface trolling attempts proved ineffective at capturing our target species, so after hauling the long-line and deploying 3 pressure-sensitive ultrasonic transmitters in Galapagos sharks, we focused our efforts on hand lining.  Our luck changed immediately as our first hand line brought up an Ulua, with more Ulua & Galapagos following from the deep reef ledge we had been setting on all day.  Using a second hand line to maximize catch rates, it did not take long for us to collect tissue samples from, and deploy transmitters in eleven Ulua and seven Galapagos sharks.

While tagging sharks and Uluas is fun, the overall goal of the project is to further understand the movements and habits of apex predators in the Northwestern Hawaiian Islands.  The use of ultrasonic transmitter tags allows us to track the local and broad scale movements of Ulua and Galapagos  sharks across atolls and along the island chain.  Similarly, pressure-sensitive tags yield the same results while also helping us understand the vertical movements of target species through the water column.   Analysis of genetic samples complements the tracking data by demonstrating any hybridization of the gene pool and clarifying ecological connectivity between geographically separated populations. The stable isotope samples further emphasize both connectivity and species position in the food web, showing both what and where these reef predators are eating. In gaining this knowledge, the importance of each species in maintaining a delicate ecological balance is better understood and therefore helps us to preserve the unique ecosystem of the Papahanaumokuakea Marine National Monument.

For more in depth information on this study and other projects associated with the Hawaii Institute of Marine Biology Shark Lab check them out at www.hawaii.edu/HIMB/ReefPredator.