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Dive Dry with Dr. Bill

#715: The Sailfin Tang

It's been six long months since I dove our waters... and it may be another six months before I can again. Being evicted from King Neptune's realm makes it very difficult to come up with fresh material to titillate your marine biological fancies. I have to rely on my past exploits to dredge up new species to write about.

After three surgeries last year, I thought it appropriate to select a fish from the surgeonfish family (Acanthuridae). One has to be careful around them because they bear sharp scalpels near the base of their tail as a means of defense. Today's species will be the Red Sea or Indian sailfin tang (Zebrasoma desjardinii) which I filmed in the Egyptian Red Sea back in 2015. It is not related to the tang used by the astronauts and young Dr. Billy back in the 1960s. However, there are actually several species known as sailfin tangs.

The Red Sea or Indian sailfin tang is known from the Indian Ocean and Red Sea. There is a related species, the Pacific sailfin tang (Zebrasoma veliferum) in the western Pacific from Australia and Indonesia north to Japan and out to Hawaii. Some scientists believe these two are simply variations of the same species.

The fish's body is basically disc-shaped but the greatly enlarged dorsal and anal fins give it a rather unusual appearance. The body has a series of alternating pale yellow and dark bands, although coloration may differ from one individual to another. It's always good to assert your own identity. They may darken in color when stressed by a predator or Dr. Bill filming up close. The head is lighter in color with many white spots and a dark band running through the eyes. Individuals may exceed 15" in length.

Like many other surgeonfish, the sailfin tang is mostly vegetarian. This fish family is often very important in clearing coral reefs of algae that might otherwise strangle the coral polyps. Sources indicate that they will also feed on plankton and have been observed chowing down on sea jellies (jellyfish for the non PC crowd like myself) and comb jellies.

Now most surgeonfish species are like my peers back in the 60s. They like to spawn in groups... kind of like the love-ins and be-ins I attended while residing in the ivy covered hal;ls of Harvard (only after my homework was completed, of course). However the sailfin tangs are either more conservative or modest as they prefer to mate in pairs.

© 2016 Dr. Bill Bushing. Watch the "Dive Dry with Dr. Bill" underwater videos on Catalina Cable TV channel 29, 10:00 AM weekdays and on Charter Communications Cable channel 33 at 7:30 PM on Tuesdays in the Riverside/Norco area. You can also watch these episodes in iPod format on YouTube through my channel there (drbillbushing). Please help me climb out of self-imposed poverty... buy my DVD's (see this link). Yes, take Dr. Bill home with you... we'll both be glad you did!

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Sailfin tang with fins extended; dark and light colored individuals.

This document maintained by Dr. Bill Bushing.
Material and images © 2017 Star Thrower Educational Multimedia