Blackfin barracuda (Sphyraena qenie) forming a circle. This species spends much of its time during the day making endless circles above the reef, as does the school of bigeye trevally (Caranx sexfasciatus) that's also consistently present on this seamount. (Inglis Shoal, Kimbe Bay)
Closer view of the same school of blackfin barracuda. (Inglis Shoal, Kimbe Bay)
Blackfin barracuda coming smoothly out of the curve. (May Reef, Kimbe Bay)
The big question is why these predators spend so much time swimming around in circles, and executing complex 'aquabatics.' (May Reef, Kimbe Bay)
The barracuda school that we frequently saw at Otto's Reef was quite spectacular both in size (over 300 of them) and in group behavior — their schooling repertoire included flawlessly-coordinated spirals and headlong plunges off the reef's vertical wall. (Otto's Reef, Kimbe Bay)
A large school of blackfin barracuda, and a smaller school of bigeye trevally, above a seamount reeftop at about 20 m depth. (Joelle, Kimbe Bay)
Professional film-maker Bill Carlson and my research assistant, Clif Haugen, get the shot as blackfin barracuda pass above them. (Inglis Shoal, Kimbe Bay)
Another shot of Bill and Clif over a different seamount. Bill was chronicling my research in Kimbe Bay for a French television production, titled Mission Barracuda, that premiered some time in 2000). (Joelle, Kimbe Bay)
One more shot of Bill filming 'my' barracuda for their debut on European television. (Inglis Shoal, Kimbe Bay)
Clif takes aim at a circling school of the same barracuda species at the same site. (Inglis Shoal, Kimbe Bay)
A school of blackfin barracuda as it makes another endless round of the seamount. (Joelle, Kimbe Bay)
Bigeye trevally frequently mix with schools of blackfin barracuda, often in closer association than in this photo. These mixed-species groups tend to be short-lived. (Joelle, Kimbe Bay)
Blackfin barracuda peel out of one of their circling maneuevers. (May Reef, Kimbe Bay)
Part of a huge school (about 1000 in the school, at its largest) passes over me, near the surface. (May Reef, Kimbe Bay)
The big school splits and then rejoins around me above the reeftop as I follow them directly beneath the hull of FeBrina and back out into blue water. This time around I was in Papua New Guinea working with a underwater film-maker Marty Snyderman and a British film team who produced a nicely-done documentary, titled Barracuda!, that first aired on September 10, 2001. (May Reef, Kimbe Bay)
Inside the same blackfin school. (May Reef, Kimbe Bay)
A massive school of blackfin barracuda pours into a rotating circle formation from above. I had to back off a fair way to even fit most of the circle into my lens' field of view. (May Reef, Kimbe Bay)
Still can't fit 'em all into my frame... (May Reef, Kimbe Bay)
The school passes over me again, off the reef in deep blue water. These barracuda generally pay little attention to human intruders on their watery turf. (May Reef, Kimbe Bay)
The front of the complete school — subgroups assembled to a strength of about 1000 fish — as it swings back out to blue water. It was very hard to fit even this within my lens' field of view, let alone try to throw much light on the subject. (May Reef, Kimbe Bay)
A blackfin school, strung in a column as it moves and endlessly changes shape, passes by a seamount's reeftop. (Inglis Shoal, Kimbe Bay)
Looking up through layers of blackfin barracuda. (Inglis Shoal, Kimbe Bay)
A closer view of a blackfin barracuda school. With a little bit of patience, it's pretty easy to get right into the middle of these schools and swim alongside the barracuda, though you're always left behind at some point. (Joelle, Kimbe Bay)
A blackfin school off the edge of a typically steep-sided reef around an offshore island. As twilight approached, the school began to cluster ever more tightly until — at sunset — it moved away from the reef and off into the darkening water beyond, toward a deep pinnacle, in a very tight ball. (Kimbe Island, Kimbe Bay)
The same large school hanging about over the same reeftop, constantly in motion. The circles that they made above this reef were some of the biggest that I've yet seen (way too big to fit well in the visual field of even my 14mm super-wide-angle lens) and being circled like that by so many fast-moving barracuda never fails to inspire awe. (Kimbe Island, Kimbe Bay)
A pair of bigeye trevally (Caranx sexfasciatus) passes before a huge school of blackfin barracuda at an oceanic reef site. (May Reef, Kimbe Bay)
A big blackfin school, spread out in a line, cruises by me. (May Reef, Kimbe Bay)
Inside the blackfin school — they kept me company out in blue water, that can be a fairly lonely and anxiety-ridden place (of course, they could care less about me, but I still appreciated their forbearance). (May Reef, Kimbe Bay)
A blackfin barracuda school's silvery wall of predators. (May Reef, Kimbe Bay)
My schoolmates. (May Reef, Kimbe Bay)
Circling around, high in the water column. (May Reef, Kimbe Bay)
Endlessly shifting patterns, folding into one another and then splitting and merging again...watching barracuda schools do their thing could be highly meditative (if not for the need to collect data, take pictures, and monitor depth and air consumption!). (May Reef, Kimbe Bay)
A relatively small 'tornado' of blackfin barracuda. These spiraling circles are apparent in smaller schools but it takes a good 300-600 barracuda to give it the real funnel-cloud look. The most spectacular that I've seen yet was by the larger school from which this group budded — 1000 barracuda in a dense helix that reached from the surface to the reef, almost directly on top of cameraman Marty Snyderman (unfortunately, I have no photographic proof!). (May Reef, Kimbe Bay)