Night Drift: Our Kona Blackwater Diving Adventure

Larval Ornate Octopus, Callistoctopus ornatus
Paralarval Ornate Octopus, Callistoctopus ornatus
Larval Ornate Octopus hangs in mid-water.

It has been almost four decades since Chris Newbert’s portrait of a long-armed oceanic octopus took my breath away. More than captivating, the magical image gracing his 1984 classic Within a Rainbowed Sea, proved transformative, opening my mind to the previously unimaginable idea of searching for pelagic animals in open ocean at night. Unfortunately, envisioning Chris drifting in open ocean at night somewhere off the coast of Kona, tempered my enthusiasm. There just seemed to be too many unknowns.

In the mid-1990s Anna and I attempted a less courageous workaround for photographing larval fish for the first edition of Reef Fish Behavior. The venture took place during our three years in Bimini where we had access to a boat and an oceanside cottage. Along with three friends from the mainland we headed for the edge of the Gulf Stream at sunset equipped with lights encased in Styrofoam, two long-handled pool nets, an assortment of buckets, dusty jelly jars from the cottage cupboard and a 12-volt car battery to power the enterprise. Surprisingly our scheme worked! 

Within minutes of connecting the alligator clips to the battery, a flurry of larvae and settling fishes fluttered around the floating lights. In no time at all a dozen strange little fishes buzzed inside our bucket. Happy with the haul, we headed to the shallows where we took individual hostages to the bottom and set them free with the hope of taking their pictures. The tiny translucent butterflyfish, quarter-sized surgeonfish, and the prize of the catch, a blunt headed flying gurnard, cooperated nicely bouncing around in a daze while the more hydrodynamic captives fled in a flash, the instant the lid was unscrewed.

Settling fishes encountered on night dive in Bimini in 1995
Settling fishes encountered in Bimini ca. 1995. L-R: Surgeon fish; flying gurnard; butterflyfish

Thinking back now some 25 years later, I find it disappointing that even with a boat and an able crew at hand, the idea of drifting at night like Chris was never considered. Making our lack of vision even more nettling, we were well aware that blackwater charters had been safely operating out of Kona on the Big Island for some time. We just couldn’t make the leap. What a pity.

Blackwater diving picked up its game in 2014 when two boat charters began scheduling open water night drifts off Palm Beach, Florida—less than a half-day’s drive from our front door! After a few fledgling dives it became apparent that diving in calm night seas with an experienced operator at the helm—whether tethered or untethered—turned out to be far less dangerous than perceived. We became hooked. Branching out we began visiting overseas concessions that have taken up the challenge of providing safe access to a new frontier (see our 2020 post about our blackwater diving in Anilao).

Riding the crest, Anna and I took a Covid test in early June and joined Steven Kovacs, a talented blackwater photographer from Palm Beach, for a week of night drifting off Kona, where it all began. We were there at the invitation of Al Rector, who had caught the blackwater diving bug and had access to a boat that could accommodate our nightly multi-dive schedule.

One of the first things we did after unpacking was trim a 40-foot line with lights staged at ten-foot intervals. Al had prearranged with our boat captain to have a rope, a large orange float and a ten-foot metal chain to stabilize the line, ready and waiting. Steve added a suitcase full of underwater lights, adjustable clamps and tie-wraps. Two hours later, what looked like an erector set on a rope was carefully wound into a plastic tub. Steve’s glowing mother ship worked like a charm, allowing us to swim freely with confidence while searching for scattered bits of larval life designed not to be found.

In Kona, like most destinations, we were carried by currents that were at times so strong we traveled five miles during an hour’s dive. Surprisingly, we were only vaguely aware that we were moving at all—the untethered divers, the line, the ball and the boat, all subjected to the same flow rate, calmly sailed along as a unit. With so much light power deployed, the captain could easily keep tabs on the lighted line and each diver’s position. A primary concern for blackwater divers is rough seas. Anything above a 3- to 4-foot chop makes it difficult to climb back aboard a bouncing boat. Strong surface winds that accelerate the movement of the floating surface ball and attached line are also avoided. Fortunately, Kona is known for exceptionally calm waters. Our group didn’t miss one of the 21 scheduled night dives during our ten-day stay.

The lighted line for our blackwater drifts
L to R: Steve and Ned assemble the lighted line (tie wraps for the win); Steve deploys the line and float; Looking down at plenty of lights for us to follow; The captain’s view of the float and lighted line (and us below it).

On our first dive the first night, we were over the side with a splash and down to 40 feet within seconds, where we stabilized and began glancing around. The lighted line hung thirty feet away glowing reassuringly through a shadowy, seventy-seven degree sea, peppered with distracting particles of marine snow (suspended organic detritus) and pulsing jelly plankton of every description. The animals we were after were out there somewhere hiding like ghosts among a profusion of reflective debris and streaming tentacles. Our job was to find them. 

As luck would have it, we struck gold on our first dive in the form of five paralarval Ornate Octopuses —Chris’s inspirational long-armed sensation of 1984, which proved to be the progeny of a wide ranging Indo-Pacific inshore species. The first octopus appeared right away hanging as still as a painting and staring straight into my eyes. The others materialized at intervals over the course of the hour-long dive. 

Finally eye-to-eye with the icon of my dreams, so bold, so wary, approaching and withdrawing again and again, vacillating between curiosity and fear. Realizing our fortune, we stayed with and worked each in turn as long as they allowed. Our decision to give our dive over to a single species proved right and a lesson relearned. On our remaining 20 drifts in Kona we only encountered one other Ornate—just one of many treasures we would never have encountered without stretching our wings and flying off to Kona.

What else were we hoping to find at night in Kona? The short answer: dramatic, seldom-seen forms of marine life. Many of the most outrageous are the larvae of deep-sea dwellers feeding in the fertile upper reaches of the ocean during their formative weeks of life—Steve’s forte. These otherworldly oddities are few and far between and require a lot of time to track down. An intriguing assortment of larval shore fishes and invertebrates, primarily the offspring of coral reef dwellers, were more common, and often every bit as ornate. We also kept a lookout for the paralarvae (larvae maturing into adults without metamorphoses) of squid and octopuses. Several of the most exquisite species nimbly weaved their elastic arms into a high state of symmetrical art when bathed in our hand lamps.

Arm Squid Brachioteuthis
Arm Squid, Brachioteuthis sp., about 3 inches. Known for its thin extendable neck. Inhabit depths from near surface to at least 2400 feet.
Paralarvae of the Sharp Eared Enope Squid, known for it various symmetrical poses.
Paralarvae of the Sharp Eared Enope Squid, known for its various symmetrical poses.
Post larval fishes seen in open water night drifts off Kona, Hawaii.
L to R: 1/2-inch Hawaiian Lionfish, Dendrochirus barberi; 1/2-inch unidentified post larval fish; 2-inch Thompson’s Flounder, Bothus thompsonii

While small, solitary oceanic squid are coveted for their photographic appeal, the larger and more numerous shoaling species often become distractions. On several dives, teeming shoals of excitable, eight-to nine-inch Purpleback Flying Squid, disoriented by our array of lights, torpedoed past at the edge of darkness. The phantom throngs often left in their wake a topsy-turvy seascape of unnerving clouds resembling flak fields from antiaircraft fire. These masses of melanin and mucus—a defensive adaptation employed to confuse predators—ranged from dark strands of wisp to thick pseudomorphs the size of soccer balls. On one sizeable flyby a Purpleback blindly crashed into my spotting light leaving behind syrupy coils of ink dangling from my strobe cords.

Our Kona expedition produced a photographic bounty of deepwater whalefishes (Cetomimiformes) larvae in families Cetomimidae (2) & Barbourisiidae (1), all sighted by Steve. Making the discoveries even more fascinating, researchers had only recently determined that what was long believed to be three different whalefish were in fact radically different life stages of the same species. The long-tailed copepod-eating oddities we photographed, known as tapetails, are actually sexually immature larvae that eventually metamorphose into either small, free-swimming deepwater males, or beefy, bottom-dwelling females with long, tooth-lined jaws and super-sized stomachs for capturing and consuming fishy prey. In the landmark 2009 whalefish paper the lead author, David Johnson, a research zoologist at the Smithsonian, wrote: “We resolve a long-standing biological and taxonomic conundrum by documenting the most extreme example of ontogenetic metamorphoses and sexual dimorphism in vertebrates.”

Larval whalefishes seen during a night drift off Kona, Hawaii
L-R: Larval Whalefish, family Cetomimidae; a second species of tapetail larva; Larval Velvet Whalefish, Barbourisia rufa

The offspring of deepwater cusk eels and dragonfishes we found—collectively referred to as exterilium larvae—trailed outlandish external guts of various lengths. Researchers are not exactly certain why larvae developed such odd adaptations. They could possibly function to absorb dissolved nutrients from seawater, or mimic the frilly appendages of jelly plankton.

Larval deep sea species: cusk eel; Snaggle Tooth, Astronesthes; Barbeled Dragonfish, Bathophilus sp.
Larval deep sea species L-R: Cusk Eel, Luciobrotula sp., about 3 inches; Snaggle Tooth, Astronesthes species, body about 2 inches; Barbeled Dragonfish, Bathophilus sp., about 2 inches

The Kona waters also concealed a rich array of larval crustaceans, most noticeable were crabs, lobsters and shrimp. While tough-as-nails crab larvae are independent, impulsive sorts that whiz by our lights like bullets, the delicate, more sedate, see-through lobster and shrimp frequently catch rides on passing jelly plankton. Far from stable, the reluctant shuttles routinely go into tumbling spasms to dislodge their unwanted hitchhikers. 

Invertebrates encountered on blackwater dive off Kona
Invertebrates L-R: Larval lobster, about 2 inches, riding on a set of Tornaria larvae of Acorn Worms; Larval deepwater Sergestid shrimp catching a ride on a salp; Tomopteris worm, Tomopteris sp., 4 inches.

Heavily armored in chitinous bumps, ridges and stiletto-sharp spines, it’s not surprising that the rarely encountered pelagic larvae of this deep-water shrimp I photographed near the end of our trip took more than 180 years to be properly classified by science. When originally found in the gut content of a dolphin in 1828, its discoverer characterized the remarkable creature as a “monstrous and misshapen animal” and placed in it own genus and species, Cerataspis monstrosa. It was only later in the century before scientists realized that marine crustaceans went through an early mid-water pelagic life stage. Finally, in 2012 DNA analysis linked the oddity with its adult life form—a typically shaped, circumglobal, five-inch shrimp, Plesiopenaeus armatus, that makes it home thousands of meters below the surface.⁠⁠

Larva of the deepwater shrimp, Plesiopenaeus amatus, about ¾ inch
Larva of the deepwater shrimp, Plesiopenaeus armatus, about ¾ inch
Ned & Anna DeLoach, Steve Kovacs, Al Rector
Happy blackwater divers off Kona, waiting for the sun to go down.

Want to know more?

Follow us on Instagram: @blennywatcher and @steven_kovacs_photography


Jeff Milisen: A Field Guide to Blackwater Diving in Hawaii

Johnson GD, Paxton JR, Sutton TT, et al. Deep-sea mystery solved: astonishing larval transformations and extreme sexual dimorphism unite three fish families. Biol Lett. 2009;5(2):235-239. doi:10.1098/rsbl.2008.0722

Bracken-Grissom HD, Felder DL, Vollmer NL, Martin JW, Crandall KA. Phylogenetics links monster larva to deep-sea shrimp. Ecol Evol. 2012;2(10):2367-2373. doi:10.1002/ece3.347