
Anilao, Philippines, February 2020
Following the lead of veteran blackwater photographers—Ryo Minemizu, William Tan, Steven Kovacs, and Wowie Cai—Anna and I headed for Pacifico Azul, a modest seaside dive resort nestled at the base of a mountainous peninsula, three hours south of Manila. The surrounding shoreline, accommodating nearly 90 resorts with dive facilities, collectively known as Anilao, is internationally famed for its menagerie of exotic muck and reef animals. In keeping with the destination’s reputation for the rare and unexpected, several Anilao dive operations, including Pacifico Azul, regularly lead guided night dives in the open water of Balayan Bay, where guests have the opportunity to hunt for seldom-seen oceanic sea creatures, primarily larval fishes, octopus and squid, that rise from the depths each evening to feed near the surface.

We had the good fortune of spending our week diving with long-time friend William Tan who arranged our itinerary. William is not only a distinguished artist with a camera above and below the water, but also a violinist for the Singapore Symphony Orchestra.
Pacifico Azul’s blackwater initiative, pioneered over the last five years by dive manager Chien-ting (Eric) Hou (also an accomplished blackwater photographer) in collaboration with veteran photographer/videographer Wowie Cai, worked to perfection, and their blackwater guides are as skilled as they come. We owe much of our success to the sharp-eyed, underwater team, Webster Mendoza, Dexter Mendoza, Regie Casia, Edwin Escleto, Ahladin Maestrado, who were not only masterful finding tiny specks of life underwater, but a hoot to hang out with between dives.

Larval Fishes and Other Plankton
The fish featured at the top of this post is a larval Crocodile Toothfish. This half-inch individual, Champsodon sp. native to the Indo-Pacific, is the first of three remarkable larvae of deepwater species we were fortunate to encounter. The fleshy flaplike projections extending from behind the pectoral fins are possibly used to disguise the larvae as frilly jellyfish or siphonophores when hovering motionless in the open water at night.

This eccentric half-inch larva, possibly a Blackmouth Angler, Lophiomus setigerus, in family Lophiidae, is a deepwater anglerfish, related to the monkfish and frogfishes. The long foredorsal spines will eventually develop into fishing rod with an artificial lure on the tip to attract prey. Adults, that look nothing like their pelagic larvae, live on mud bottoms at depths to 1,500 feet.

Getting even stranger, this stalked-eyed larva from family Stomiidae, trails a developing gut (exterilium) outside of its ¾-inch body. The larval fish will eventually mature into a ferocious, long-toothed, eel-like denizen of the deep with light organs extending down its body.

A Phronima amphipod, an adult pelagic crustacean (commonly assumed to be the prototype for the xenomorph queen in the Alien movies) riding inside a highjacked salp where it later incubates its offspring. Phronima are frequently encountered on blackwater dives, but seldom display colorful highlights like the pictured individual.

Small and delicate, this is a three-inch version of the five-foot adult female Blanket Octopus we had hoped to track down—maybe next year.

Another small female Blanket Octopus. Looking closely you can see strands of broken stinging tentacles extending along the female’s sucker-lined arms—a residual artifact of its symbiotic relationship with jellyplankton, such as a Portuguese Man-of-War.

A marquee blackwater larva in the Western Pacific; commonly believed to be a Wunderpus Octopus.

Tiny unidentified squid—Maybe ¼-inch at best, this colorful cutie danced in my lights for minutes.

This chubby little pea-sized squid shatters its kin’s conventional reputation for sleekness.

Unidentified planktonic octopus paralarva. We nicknamed them the “Squidopus” because of their streamlined likeness to a swimming squid.

And just a few seconds later, the same octopus paralarva assumed a more typical octopus-like pose.

A ¾-inch larva of the family Platycephalidae, commonly known as flatheads. The Crocodile Flathead is a common family member found on Indo-Pacific reefs.

Unidentified tonguefish larva – Less than ½ inch long, this larval tonguefish, like other family members, develops an external gut while in its pelagic larval stage.

Another unidentified tonguefish larva – Also less than ½ inch in length, this larval tonguefish, like other family member, develops an external gut while in its pelagic larval stage. Tonguefishes, along with flounders, belong to a group of fishes known as flatfishes. As they mature into the more common bottom-dwelling fish, one eye migrates over to the other side. Like the tonguefish in the previous image, this one has not yet gone through that metamorphosis.

Unidentified scorpionfish larva – Just under ½ inch, larval scorpionfish exhibit over-sized pectoral fins similar to the closely related lionfishes (next image).

Unidentified lionfish larva—No more than a ¼ inch in length, this tiny lionfish spreads its enlarged pectoral fins, thought to mimic jelly plankton, when hovering.

Larval eel—The translucent ribbonlike bodies of larval eels are collectively known as leptocephali. When disturbed, they characteristically curl into a tube-like shape possibly mimicking the appearance of salp. The green body margins are unusual.

Young Pompano—Juvenile and young adult pompano trail long filaments from their dorsal and anal fins. The wispy 12-inch appendages, on this photographed fish, are lost as the fish matures.

Crab zoea—Early larval stage of crabs often bear elongate spines for defense. The body minus spines on this individual is only 1/8 inch across.

Crab megalopa—A more developed larval stage of crabs, approaching ½ inch in length.

Lobster larvae typically hitch rides on different forms of jelly plankton, in this case a box jelly. It looked like a competitive log roller maintaining its balance on the moving jelly.
After 50 years of underwater exploration, the discovery of new animals and the company of friends is as sweet as ever ~ Ned

References and additional reading:
M. D. Norman , D. Paul , J. Finn & T. Tregenza (2002) First encounter with a live male blanket octopus: The world’s most sexually size‐dimorphic large animal, 36:4, 733-736, DOI: 10.1080/00288330.2002.9517126
Biology Of The Planktonic Stages Of Benthic Octopuses, Villanueva R, Norman MD Oceanography and Marine Biology: An Annual Review 46: 105-202 (2008)
Night Drifters, Alert Diver Magazine, Winter 2017 – Our article about joining friends for a blackwater dive off Palm Beach, Florida and features some of their images.
Journey’s End, Alert Diver Magazine, Winter 2018 – Our article about our blackwater dives in Bonaire and Dominica.