Rocking and rolling

We’ve been steaming for Pearl and Hermes atoll since leaving FFS some 30 hours ago. We have another 22 or so hours before we arrive at roughly 6 am HI time, ready for a full day of diving operations tomorrow. Lauren and I have some time to clean and repair equipment, and start processing/storing the ~110 GB(!) of data we collected before we arrive.

The unfortunate weather we are currently enduring.

Since we left FFS, the weather has deteriorated. Winds have been gusting steadily 15-22 kts from the southeast. GOES infra-red satellite images show the remnants of a tropical storm right over us. We’ve enjoyed a following sea but now the swells are larger- things are starting to fall off tables and sleep is harder to come by. We’re hoping the kidney-shaped atoll at Pearl and Hermes provides a little shelter..

The acoustic array deployed in an L-shape. Thank you Mike and Fernando!

The last day at FFS (Monday) was a great one. We were surprisingly organised, driving 7 km to the site where we deployed the array and other equipment on Saturday, doing 4 dives to remove all the gear, and finishing up before 11am! Removing the array was surprisingly straightforward, bulky as it is.

Simon raising the buoyant array to the surface.
The array ascends back to the dive boat.

A little thought and pre-planning went a long way when figuring out how to get the thing in to the boat and stow it away so people wouldn’t trip over it. We deployed four time-lapse cameras (1 image every 5 minutes) on the ‘windmill’-shaped PVC camera frame…all of which 1) worked 2) didn’t flood! The ebay-sourced second hand cameras seemed to have earned their keep.

Lauren holding on to our surface marker float – essential because if the boat loses us, we’re truly gone! (Don’t panic moms- it is attached to her, and we each have another backup marker too)
Lauren, Simon, and friend at La Perouse.
La Perouse head-on. Very thin. Lots of birds.

Given that we had the afternoon and that the swell on the windward side of FFS was again picking up to sickness-inducing levels, we ran 18 km down-swell to our second site for coral surveys – La Perouse rock. The northernmost basaltic outcrop in the Hawaiian Islands archipelago (and the next to eventually submerge and be re-absorbed into the crust), La Perouse is the shattered remnant of some long-extinct volcanic crater rim. No more than a thin sliver of rock (only 30 m or so wide and about 200 m long), the island is covered with thousands of nesting seabirds. As we approached the birds took to the air and filled the skies, squawking in protest at our arrival. After ten minutes or so however, they settled down and began approaching our boat in groups, hovering over the boat by a couple of metres and eyeing potential landing sites.

Giant table corals and a few other species make up the bulk of coral biomass. The damselfishes are very reminiscent of the two-spot demoiselles in New Zealand, following divers in their hundreds.

Diving La Perouse was very different to the atoll rim. Where sandy bottom and wave-swept coral dominated the first site, La Perouse was surrounded by basaltic boulders that gave way to typical spur-and-groove coral reef at around 12 m. Giant table corals more than 3 m across indicated that this place was relatively more sheltered than the exposed outer atoll slope. Besides from one alua and a few white-tip reef sharks, few large predators were seen. No lobster to be found anywhere either, even though the basalt rock was highly perforated with ideal nooks and crannies in which they could hide. The impression La Perouse gave us was of a patient in recovery – something our chief scientist Scott Godwin confirmed later on: La Perouse was heavily fished until 2008, and is still recovering from the effects.

Lauren photographs Simon under La Perouse.

Approaching the side of the island at the end of a dive, we were astonished to see sunlight coming from its base. A small cave at around 10 m depth means that it is possible for a diver to swim through the island! The swell striking the windward side of the island created a strong suction effect, pulling us (temporarily) through to the other side. Later on, Simon was snorkeling around the island when he saw a little face poking out from under an overhang. A Hawaiian monk seal cautiously poked its nose out of its hideaway, waiting for the right opportunity to come back to the surface for another breath. Upon seeing the snorkelers, the seal shyly left the area. Two yellow scientific tags on its tail were testament to its previous encounters with humans. Perhaps this is why it seemed so shy?

Happy and worn out after a successful (and fun!) day of science diving

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