On Aitutaki, Sunday is a day of rest for everyone. Except for 2 places 🙂 All of the stores are closed and people spend the day with their families after morning religious ceremonies.

This morning some of the group accompanied the professors to the local church and the rest of the group stayed to enter our first round of official data. 

This afternoon Aspen, Vanessa and I are resting at the beach near the Boat shed to enjoy the afternoon off. Tomorrow will be back to work! 

 

Another night dive and another success for capturing fluorescence from the ROV! The payload developed for this had stopped working, which we’re currently troubleshooting. As such the dive flashlight was attached to the payload bar and after Paul and Chris had helped to achieve the desired weight distribution and buoyancy, we deployed the ROV in the same place as last time (North Aitutaki). We made three transects with the first starting directly ahead of us (North) where we found there to be a considerable current which the ROV was getting caught in, though we did see small amounts of fluorescence. A second transect started West and was flown out to 40m, where we saw flecks of fluorescence. A third transect started West and was flown out to 50m from the beach, which moved with the current East, zig zagging across the coral. This transect proved to be the best distance as we captured extensive areas of green fluorescence!

Several of our group undertook a night snorkel at Airport Beach last night. The moon was full, the water was warm and the corals were busily fluorescing. We spent an hour swimming between coral bommies looking at the fishes that were active during the night, including iridescent cardinal fishes, squirrelfishes and a curious porcupine fish that came to investigate the dive lights. We also saw several invertebrates that we had not observed on the reef during the day, including some photophobic sea cucumbers and a couple of species of shrimp.

The Marine lab on Aitutaki is housing a multitude of giant clams, while doing research on the impacts of amino acids in their survival. With the addition of these acids to their diets, the clams were found to survive longer and thrive better in their environment. In the wild, these clams are unlikely to survive past the first three days, with almost 99% not surviving past the first 24 hours of life.    
   
Their amazing colors are because of a phenotype variation, just like that of eye color in humans. 

Tonight we launched the OpenROV equipped with the payload to detect fluorescence in the ocean. It consists of a blue LED strip (excitation source), a power source and a GoPro with a yellow filter (detection). It was launched from the North of Aitutaki in the Cook Islands where an abundance of life exists, including corals, fish, clams etc. Given that many corals are known to fluoresce, our aim for the first trial was to detect fluorescence emitted from a coral. After only 9 minutes in the water fluorescence was detected! A fantastic green hue was observed coming into the view of the camera ending with the coral being seen to fluoresce at about 60-70cm. We believe the coral in the photo is a member of the Porites genus, though this is difficult to tell. Whilst the fluorescence is dimmer than using a torch, this proves the principle that we can detect fluorescence from an affordable ROV (OpenROV) which people from all over the world can have relatively easy access to. We hope that this method can be used to assess coral health and discover a novel fluorescent protein and proving it works is a massive step forward in this research. Perhaps this is the beginning of a great way for everyone to join in and start to systematically assess coral health.

Furthermore a vivid pink colour was observed (picture not shown) using a blue diving torch and a yellow filter and whilst this can be seen in normal conditions, it is particularly vivid with the torch. This was later identified to be a disease that affects Porites coral. So we should definitely quantify the pink areas as well as the total fluorescence as a proxy for coral health.

A few adjustments need to be made to optimise the performance of the ROV, including tinkering with the weight distribution, ballast and buoyancy of the payload. Given the torch has shown better results at the same distances, we may also try and attach it to the ROV and compare the data. Furthermore we ran into a few problems with the tether getting caught on corals, as such we’re going to use a positively buoyant tether on the next tests to avoid this happening again.

The group visited a marine lab on Aitutaki today and met with Charlie Waters. Charlie recently finished a PhD focused on the giant clams of the Cook Islands. These clams were heavily overfished until they became functionally extinct (could not reproduce in the wild). Clams are important filter feeders in the reef ecosystem and are an important food source for octopus, porcupine fish, parasitoid snails, humans and multiple other animals.
The clams engage in a symbiotic relationship with phytoplankton (photosynthesizing plankton). The clams rely on the plankton for energy and have trouble surviving without the phytoplankton.
The lab has tried to implement reintroduction of multiple species of clams but poaching continues to ruin the efforts. In an attempt to come up with a solution, Charlie believes the best method is to educate youth and tourists on respecting the reef system. Hopefully these educational programs will eventually allow a successful reintroduction of these beautiful animals to their natural habitat.

   
On Thursday we left with the start of the sun peaking across the water to do a full day of surveying in the lagoon surrounding the main part of Aitutaki. We left the dock and zipped across the clear turquoise water to see the amazing coral reefs in the lagoon.  As the boat stopped we were greeted by a Giant trevally and crystal visibility.

We found Flametail snappers, Honeycomb groupers and Vanessa spotted a Scribbled pipefish!  With the help of the awesome Dr.Steele we were actually able to learn what all the pretty reef fish are as scientists instead of you typical tourist snorkel. 

As we ventured along the white sandy bottomed lagoon, large piles of corals called Bommi’s, would appear like mountains under the sea. Villages of fish and coral species were mystical to see.

We stopped on Barefoot island, a bit of a tourist spot to get our passports stamped as a special Cook Islands treat!

Once we were on the far Motu, a small island on the outer edge, Dr. Anderson helped us identify awesome invertebrates and some cool worms we haven’t even identified yet! 
The day was magical, we learned so much and are so greatful for the amazing opportunity! 

 
On Thursday we left with the start of the sun peaking across the water to do a full day of surveying in the lagoon surrounding the main part of Aitutaki. We left the dock and zipped across the clear turquoise water to see the amazing coral reefs in the lagoon.  As the boat stopped we were greeted by a Giant trevally and crystal visibility.

We found Flametail snappers, Honeycomb groupers and Vanessa spotted a Scribbled pipefish!  With the help of the awesome Dr.Steele we were actually able to learn what all the pretty reef fish are as scientists instead of you typical tourist snorkel. 

As we ventured along the white sandy bottomed lagoon, large piles of corals called Bommi’s, would appear like mountains under the sea. Villages of fish and coral species were mystical to see.

We stopped on Barefoot island, a bit of a tourist spot to get our passports stamped as a special Cook Islands treat!

Once we were on the far Motu, a small island on the outer edge, Dr. Anderson helped us identify awesome invertebrates and some cool worms we haven’t even identified yet! 
The day was magical, we learned so much and are so greatful for the amazing opportunity! 

We went snorkeling in the lagoon of Aitutaki Island and explored some of the smaller Islands in the lagoon called “motus”. The first was named Motu Ketiu and had multiple species of birds nesting on the Motu. I was able to identify red footed boobies, brown boobies, red tailed tropic birds, white tailed tropic birds, common terns, and I was excited to see my first frigate birds.
The next Motu was a newly formed sand bar that had a few coconut saplings (locally called “huto”). We had lunch and made our first UAV launch from this particular Motu.
We then ventured to a large Motu where the Tasmanian Empire Airways Limited had set up a stopping point in the early 1950s. Here we tested our sandy beach protocol and found that the beaches on these motus are low in diversity unless coring is done in knee deep water, where multiple species of tube worms and crustaceans were found.
Overall, quite a few discoveries were made today that filled the group with anticipation for the future research yet to be done.