A Long Dive

Photography can be a tedious pursuit, even more so underwater where conditions can be very challenging. This leads to a regular issue in mixed dive parties. The photographers go slow, really slow. The other divers are ready to cover some ground. This occasionally means that the guys leave me behind.

Dive Profile
Dive profile for Suck ‘Em Up Cave
While diving alone is not recommended, the risk can be mitigated. I shift to a different set of rules, a far more conservative set of rules if I am on my own. I keep the depth much shallower, to where I could do an emergency ascent with little risk, this is generally 30ft or less. I do not go very far into a cave, perhaps working the twilight zone, but not getting into the back recesses of the many little caves common along the Kona coast. These sort of rules are usually not much of a compromise. Almost all of the dive sites on the Kona coast can be enjoyed while staying shallow. Many of my best finds have been in the twilight zone of the little reef caves. Staying shallow also has the benefit of extending the dive dramatically, it simply takes far less air to fill your lungs when shallow.

Gosline's Fang Blenny
Gosline’s fang blenny (Plagiotremus goslinei) sheltering in a worm tube, 20ft depth, Suck-Em-Up Cave
Suck-Em-Up cave fits the bill. The maximum depth here is 30ft, and there are so many entrances and skylights that an emergency ascent is always possible. The rest of the guys are planning to sweep the reef face and take a deep excursion before heading to the cave. I am planning to simply dive the cave as I have several photographic targets in mind. I am first into the water, swimming a few feet from the boat awaiting Pete, Ben and Dennis. A loud pop and woosh announces a blown o-ring on an air tank for Pete, this will lead to a short delay. I signal that I am dropping anyway, they know where I will be. The cave entrance is only a few yards from the boat. I give a salute and they wave back as I slide under.

Bloody Hermit Crab
Bloody hermit crab (Dardanus sanguinocarpus) in a cave at 20ft depth
A couple lobsters, several hermit crabs, a couple nudibranchs, feeding moorish idols, walls of colorful sponges, all the usual stuff you expect in a reef cave on the Kona coast. There are two entrances here, I enter on the north end, the entrance that earns the cave its name. The surge is pretty easy this day and the hoover action is minor. On more active days the surging water seems to suck you into the cave mouth, a bit like a bit of dirt into a vacuum cleaner. I sweep from end to end of the cave doing a leisurely reconnaissance. What do we have today? What do I want to spend my time on? Where are the best photos?

With no real time worries I took my time shooting each subject. Find a hermit crab? No problem, just set the shell in a nice pose and wait the minute or two it takes for the critter to decide the danger has passed. The crab will emerge to right its shell. Of course the crab is greeted by a blast of light as the strobe fires. It may retreat, but so often they do not, I can get in two or three shots before the shell is once again upright and the crab is on its way.

Flat Rock Crab
A flat rock crab (Percnon planissimum) among boulders in Suck-Em-Up Cave at 25′ depth
One of the targets I hoped to find are the little flat rock crabs. I know they are here. These colorful critters really are flat. Purple and red limned with bright gold these little fellows make nice photographic targets. The only issue is the crab’s preferred perch, sitting the the crevice, right where two round boulders touch. I find several crabs before I find one situated within easy reach of the camera and strobe.

An hour into the dive I locate the oddest find of the day. I see a little fish just poking its head out of a worm tube on an otherwise sheer rock wall. I make a guess that this is some sort of blenny, only a few inches long and maybe half an inch high. Hitting the books later I identify the fish as gosline’s fang blenny. The fish is an ambush predator, but it does not kill its prey. Fang blennies simply take a nip out of passing fish, usually much larger fish. They are also known to occasionally take a nip out of scuba divers as well. Of course I find this out after I get out of the water, not when floating a couple feet in front of the fish in question.

Toward the end of my dive the guys show back up again. I spot Pete just outside of the large southern entrance of the cave where I am photographing a nudibranch. Just beyond Pete is a large diver sized object that is not a diver. A whitetip shark has appeared as well, taking advantage of a cleaning station just outside of the cave entrance and under a large overhang. Finishing up on the nudi I join Pete in shooting the shark. I also point Pete to the fang blenny in the wall at the cave entrance.

Tiger Snake Moray
Tiger snake moray (Scuticaria tigrina) at 30ft depth, Suck-Em-Up Cave
As I head back to the boat Dennis signals to me, there is something in the coral head. I only have a few hundred psi of air left, but I drop down to take a look anyway. There is a snake moray curled in the coral. Time for a couple more shots before heading to the surface with only 150psi left in the tank. Breaking the rules again, but I am only 30ft down and almost under the boat. The result is probably the best photo of the dive. Not bad considering this was a great photographic dive with several good photos on the card.

In the end I logged a 95 minute dive, one of my longest to date. A shallow dive at a very relaxed pace kept air consumption to a minimum, a SAC rate of 0.45ft³/min. Still, anything over an hour and a half is doing pretty good on a standard Al80 tank. A long dive, and some really nice photos to show for it.

Author: Andrew

An electrical engineer, amateur astronomer, and diver, living and working on the island of Hawaiʻi.

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