The open ocean is at best a fickle place. The weather is always unpredictable. The sea ruins the hardiest of equipment. We can only do what we can.
Day two at French Frigate Shoals (today, August 5) sees us on board the R/V Hi’iakaiai without a tender – a loading wire on one of the davits was found to be frayed this morning, meaning the ecological survey team – which has priority – commandeered our boat to do their work. Even then, they had to leave four of their team on the boat as our vessel is smaller than theirs. So it transpired that Lauren and I have a day on board the mothership (Hi’ialakai) to rest, reflect, and prepare for tomorrow after a hectic first day. The downtime is also a great opportunity to write a blog entry!
Our arrival at FFS was made apparent to us by the sighting of a large object in the distance, La Perouse Rock. This and the small sandy islands on the atoll, are the only land for hundreds of km around. An excellent visual reference from which to get your bearings around FFS, La Perouse is also home to thousands of boobies (sfw). These birds now regularly fly past our boat, using our wind shadow to accelerate in the direction they need to fly.
We met with considerable success yesterday, although it did not come without cost: we were completely strung out and exhausted by the end and Simon was plagued with seasickness the entire day. Four dives in open-ocean swells on the windward side of the shoal were completed. In the process, two single-hydrophone recorders were deployed, the 11-hydrophone fly-by array was also deployed, and the ‘windmill’ – a bottom-mounted tower holding four time-lapse cameras, was secured to the bottom.
We even had the opportunity to conduct several benthic photo-transects and stationary fish count estimates! However, we also found that the flyby array was a challenge to maneuver and deploy from a pitching and rolling small boat. Simon also found that assembling the flyby in such weather was exceedingly difficult and leads to vomiting sessions off the side… Luckily once the array was in the water and we were underneath, things calmed down greatly.
Even though we had made it to the bottom with their equipment, the challenges continued for us. The bottom environment on the southern side of FFS is dominated by large tracts of coral rubble, patchy reef, and white sand. Large, living reefs don’t occur in this area due to the occasional cyclone that comes this way and destroying the windward reef. While the sand looked like an ideal substrate into which one could screw in sand anchors, it seemed that in most places the sand only formed a thin veneer over hard coral. After about a dozen tries (3 mins of work per try), we finally found a place where the anchors ( about 4 ft, 1.25 m long) could be driven in to the ground more than half their length. After so much thought on where to put the acoustic instruments to extract the maximum scientific value from the recordings, it seems now that the deciding factors are simple: 1) near the reef 2) where the sand is deep enough to securely anchor the instruments.
We spend so much time concentrating on deploying the equipment and collecting information about the benthic habitat we almost forget to look up and miss some of FFS’s wonders! The first dive of the day seemed like diving in some kind of crystal palace. Visibility was much better than 40 m horizontal (130 ft) and the colour of the ocean was an intense blue. As we descended, long sinewy shapes moved over the sand – the shadows of large crimson jobfish swimming towards us to see what the commotion was all about. They were soon joined by giant trevally or uluas that seemed to act completely without reservation – no fear of spears or hooks, swimming tight circles around us at arms length. The quantity of predatory fish in this area is surprising although not unexpected – this reserve has not been fished (legally) for many years.
The small boat transits are extremely exciting. We aren’t allowed to sit, because the jars and bumps can damage your back as we go over the big waves! Yesterday we got a full on water-park effect when we plowed straight into one. Fortunately the scuppers worked well. Everything we brought on board was soaked, and eating lunch was a bit of a joke. Simon wasn’t eating much anyway, and Lauren struggled to eat small packaged foods without them getting a salt wash first. We worked hard under and above water, and made it back safely. Our coxswain is awesome and we are glad to be working with him!
Now we wait anxiously for tomorrow. The hydrophones were deployed in an area that is a little rougher today as the wind is now blowing 25 kts from the south east. Will we get our equipment back in once piece? Will Simon be overcome by seasickness again?