Last week I wrote about the magnificent anemone (Heteractis magnifica) that I photographed while diving off Vanua Levu in Fiji this past April. But no discussion of tropical anemones would be complete without mentioning the array of fish that have evolved to live within the stinging tentacles of the anemone. This week’s anemone (Entacmaea quadricolor) is commonly known as the bulb anemone, bulb-tip anemone, bubble-tip anemone, or bulb-tentacle anemone, among other names. As you can see in the photo, especially the lower right area, the tips of the anemone’s tentacles are swollen into little bubbles. These bulbs typically only form once the anemone has become a host to an anemonefish, or clownfish. Yes, this is the fish made famous by the movie Finding Nemo, but these fish are quite real and have a very special evolutionary relationship with their anemone.
The anemonefish in this week’s image is the Fiji anemonefish (Amphiprion barberi). And, unlike most other species of fish that might swim into the anemone’s tentacles, it is not stung by them. In fact, the fish is protected by the anemone, while providing the anemone with some nourishment in the form of leftovers, slime and other organic material provided by the fish. Both the anemone and the fish gain benefit by living in such close proximity, a relationship known scientifically as a symbiosis.
I made today's photo using my Canon 8-15 mm f/4L fisheye lens mounted on my Canon 5D Mk. III in an Ikelite underwater housing. I illuminated the scene with two Ikelite DS-161 strobes in eTTL mode. The exposure was set to 1/60 sec at f/8.0 and ISO 200.