A slide-show late one night sent fish experts reaching for their books: just what was that hairy fish? Fred Bavendam joined the hysteria of the ensuing search to find its name
It was show and tell night at Kungkungan Bay Resort, Sulawesi. The slide projector was set up and Denise Tackett led off with a selection of pictures she and her husband had shot over several years as the resident photo pros of the resort. On any other night, the Tacketts' impressive slides would have received rave reviews. But that night's audience was the underwater mafia. On one side of the projector was Scott Michael from the US, a marine biologist and author of several fish books. His typical response to most of the Tacketts' pictures was: 'that's nice,' said in the same way a guy might say: 'she's got a nice personality,' about a girl he doesn't fancy. Yet Scott's low- key comments were wildly enthusiastic compared to those of Roger Steene, a well-known Australian underwater photographer. His reaction to almost everything shown was: 'ordinary', or 'nothing special there'. I didn't say much at all because when I'd made my reservation Denise had told me she expected me to bring some slides to show. And I was up next. I got off pretty lightly. My macro shots received the same kind of abuse as had Denise's, but my wide-angle scenics garnered a few genuinely positive comments. I'd shot a few half-over half-unders in Manado the year before which had elicited a couple of, 'fantastic' comments from Scott; and even Roger had responded to several taken at sunset with: 'That's really good, how'd you do that?' I'd survived. As I was putting my slides away, another guest, John Greenameyer from California, asked if he could show a few pictures. Why anyone would volunteer to go before that night's firing squad, is anyone's guess. But his slides, mostly from the Solomon Islands, were good. After a couple of excellent images of clownfish and shrimp gobies, John showed us a fish that looked like a werewolf. It was greenish brown with dark eyes, a big mouth, and covered everywhere with long hairy tendrils. From Scott's direction all I heard was a low, 'wow'. And Roger, who over the course of the evening had slouched deeper and deeper into his chair, bolted upright croaking: 'What the hell is that? It's incredible! Where did you shoot it?' John's answer created instant pandemonium. 'It's some kind of frogfish and I shot it here on the night dive two days ago. I had the film processed this afternoon because I was hoping you guys could tell me what it was.' John was right. It was unquestionably a frogfish, but the fish photo godfathers, even with the help of all their books, couldn't put a name to it. Frogfish fever gripped Kungkungan Bay Resort and even I was not immune. That the fish mafia at Kungkungan Bay hadn't been able to put a name to the frogfish in John's picture wasn't surprising. Identifying frogfish has bedevilled even the experts for years. And no wonder. Frogfish are capable of radically altering their coloration to blend in with their surroundings. And the general body texture from one individual to another within the same species can also be quite different. So it's possible for a dark brown frogfish with a hairy body to be the very same species as a white frogfish with almost smooth skin. This incredible variability in appearance resulted in biologists giving individual species of frogfish over two dozen different names based on appearance and location. Then, in 1987, in a book called Frogfishes of the World, Theodore W. Pietsch used more stable characteristics such as fin ray counts, dermal spines, and the shape of the frogfish's lure, a fleshy protruberance at the front end of its dorsal fin also known as the esca, to re-classify 165 named species into the 41 frogfish recognised today. On the days - and nights - following the slide show, the dive site where John had photographed his frogfish, Aer Prang, became the destination of choice. Not a single rock or clump of algae went uninvestigated. Almost every mealtime we indulged in speculation on the frogfish's identity. But since John's photo did not show the esca, no conclusive identification could be made. Smart money was riding on the shaggy or hispid frogfish, and there was also some thought that it might be an entirely new species - which would be a veritable holy grail to a fish biologist. But despite a lot of dives by a lot of divers, the hairy frogfish eluded us. That is not to say the dives we made hunting for it were a total failure. We found a multitude of interesting subjects - flying gurnards and dragonets, strange octopuses and rainbow coloured nudibranchs, and even several different kinds of frogfish. But not the frogfish. Finding frogfish isn't much easier than identifying them. Their coloration usually matches the local substrate to such a remarkable degree that they are almost invisible even in plain sight - exactly what a lie-in-wait predator wants. Kungkungan Bay is always a good place to go looking for frogfish, but the autumn of 1997 seemed to be a bumper year even by its standards. By the tenth day of my 15-day stay I had photographed 11 different frogfish. Among the twisted yellow sponges at a site called Police Pier I photographed a tiny painted frogfish only 2cm long and a somewhat larger warty frogfish, both yellow; also a 25cm orange commerson frogfish. At Aw Shucks I shot several more colorations of the painted frogfish including a small white one wrapped around a colony of white compound ascidian waving its lure at a nearby goby. Almost every dive trip has one or two special days and the twelfth day was the big one for me. On an afternoon dive at Aw Shucks I had just begun to take pictures of a small octopus when suddenly Denise was pulling excitedly on my leg. I abandoned the octopus and followed her to where dive guide Robinson was pointing to a 2.5cm-long flamboyant cuttlefish, a really rare find. I'd managed to shoot only half a dozen frames of the cuttlefish when Scott Michael grabbed me and pointed to a little 3cm frogfish only metres away. It was brown with a large dark spot on its dorsal fin. Great, probably a different species from any I'd seen or photographed before. Low on air and out of film, I was on my way back to the boat when the second dive guide, Samuel, caught my eye and led me to still another frogfish. This one was incredible. Fifteen centimetres long, it had dark stripes radiating from around its eyes and feathery barbells on its chin. I showed Samuel my air gauge and then used hand signals to indicate I was going up to the dive boat for another tank and wanted him to stay with the fish until I got back. Ten minutes later I was back in the water with a new tank and fresh film. But I couldn't find Samuel. Almost in a panic I swam around and around looking for the frogfish without any luck. Then I heard Denise's squawker, and found both Denise and the frogfish. Samuel had also run low on air, but had got Denise to take over as frogfish guardian before he left. After sitting next to a clump of algae for a couple of minutes the frogfish began walking along the bottom, moving from one algae clump to another. After almost half an hour the frogfish reached his destination, a clump of algae in which a second, slightly larger frogfish sat. And the second frogfish was covered with long greenish filaments! It was John Greenameyer's frogfish! Or one just like it. And resting against its head was an esca that looked like several worms. The mystery was solved. Both the frogfish I had been following and the hairy frogfish were striated frogfish, Antennarius striatus. Over my last three days at Kungkungan Bay I returned to photograph the pair of striated frogfish several times. And on another dive at Aw Shucks my dive buddy spotted an 18cm brown painted frogfish sitting in a colony of brown sponges. But nothing would ever quite match the excitement of the twelfth day when we finally found the hairy frogfish. In their book on Pacific marine fishes, Burgess and Axelrod state that, 'most anglerfishes are ugly and colourless..., no great interest...'. Despite having seen only a couple of dozen frogfish, I couldn't disagree more. Their ability to adapt to their habitat is amazing and their feeding behaviour incredible. I have to say, I find frogfish positively alluring.
How does it do it?
When a frogfish strikes, it takes just 1/30 of a second to grab and eat its prey - too fast to be visible to the human eye. It opens its mouth rapidly and sucks in its prey before the victim realises what is happening. It can increase the volume of its mouth twelve-fold and swallow prey as large as itself.
Jet-propulsion is a common method used for getting around. Frogfish swallow water and expel it through small round openings behind the pectoral fins, essentially the same action as breathing, but more forceful. When using jet-propulsion, a frogfish appears to levitate and drift along using its fins as stabilizers.
Frogfish are weak swimmers. Swimming using the caudal fin or tail for propulsion is not frequent and only really used for brief dashes such as fleeing from a predator.
Most tropical water frogfish lay eggs as a gelatinous mass that expands on contact with seawater, absorbing sperm ejected by participating males. After floating near the surface for a few days, the raft sinks to the sea floor and the eggs hatch far away from their parents. Other species lay fewer but larger eggs which the male guards until they hatch.
Frogfish possess a highly modified first dorsal spine that they can wave about. At the tip of this spine grows a bit of flesh, known as the esca, that resembles food and entices other fish into its striking path. The diner becomes dinner.
The esca often simulates a particular kind of prey. Some look like worms, others resemble small fish. Esca often also imitate the features of the prey item, such as wriggling, swelling up or emitting a chemical.
Frogfish adopt an appearance that matches a particular habitat not as a defence but as a means of remaining unseen by their prey. This combination of using coloration to appear a part of a prey's normal habitat while using a lure to attract that prey within striking distance is called aggressive mimicry and is the frogfish's trademark.
Often frogfish walk, using the two pectoral fins and pelvic fins. This can be slow when stalking prey, or a faster 'gallop' for traversing open territory.