Photo of the Week: May 24, 2010

Hi Gang!

This week’s POTW is a shot of one of my favorite Hawaiian fish, the bicolor anthias (Pseudanthias bicolor). No doubt, bicolors are beautiful fish, and there is simply no way to pass them by if you have a camera with a macro lens in hand.

All anthias are members of the family Serranidae, a grouping that includes groupers, seabasses and fairy basslets. The seven genera of anthias make up a subfamily known as Anthinnae. Interestingly, all bicolor anthias begin their lives as females. Discovering this fact often makes the newly informed scratch their heads as they wonder how the species perpetuates itself. The answer lies in the fact that bicolor anthias are hermaphrodites, meaning that in a given population a dominant female will eventually become a male. As a male, the fish will then rule, or preside over, a harem of females. A typical harem consists of a single male and as many as a dozen females.

Some species of anthias shoal in shallow water, but the bicolor anthias tends to prefer deeper water as they occur at depths between 16 and 223 feet. The bicolor anthias is an aggregating species that is usually found near caves, ledges or other cover in areas where currents are common. In the case of this week’s POTW, the five-inch long fish was found in around 100 feet of water as it swam around a very small coral head with roughly a dozen other members of its species.

The pictured fish is a male. The long second and third dorsal spines that have a membranous tip, and that are used for display, make it possible to determine the sex from this picture.

Once found, the bicolor anthias is reasonably easy to photograph because they tend to stay in a relatively small area. Getting the right pose requires some good luck and patience. The specimen in this week’s POTW was being cleaned by a scarlet cleaner shrimp, and it opened its mouth in a display to request cleaning. Right place at the right time, or, as I said, a combination of good luck and patience!

I took the shot with a Nikon D300 and a 105 mm lens in a Subal housing. I used a pair of Ikelite DS 160 strobes to light the shot. I set the strobes on full power so that I could use the smallest possible aperture in order to maximize my depth-of-field. Even with the maximum depth-of-field I couldn’t get the entire fish in focus because of the fish’s orientation to my camera. That meant I had to be sure to focus on the fish’s eye so that the eye would be in razor sharp focus, the head and mouth would be sharp, and any soft focus area would be toward the tail.

I hope you enjoy this week’s POTW!

See you next week,

Marty