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Photo Information
Copyright: Alfredo Wang (alfhwa) Silver Star Critiquer/Silver Note Writer [C: 10 W: 0 N: 19] (93)
Genre: Animals
Medium: Color
Date Taken: 2007-10-24
Categories: Fish
Camera: Olympus Stylus 770SW
Exposure: f/5.0, 1/800 seconds
More Photo Info: [view]
Photo Version: Original Version
Date Submitted: 2007-11-21 6:53
Viewed: 5549
Points: 2
[Note Guidelines] Photographer's Note
Shot taken at Coki beach, in St. Thomas.

Order: Perciformes
Family: Acanthuridae
Genus: Acanthurus
Species: chirugus

Doctorfish are associated with shallow marine waters 6-130 feet (2-40m) over rock bottom or coral reef habitats. They are also frequently found foraging through inshore seagrass beds, traveling with schools of A. bahianus.

This fish is high-bodied and compressed, resulting in a pancake-like shape. The eye is high on the head and the mouth is small. The dorsal fin is continuous. Of particular interest is the sharp, scapel-like spine that is located on each side of the body on the caudal peduncle. This spine can be extended and used to fend off aggressive encounters. Its teeth, specialized for scraping algae, are spatula-like in shape, close together, and notched on the edges.

Doctorfish frequently reach about 12 inches (30 cm) in length, with a maximum size of 14 inches (35 cm).

The doctorfish is a diurnal grazer, feeding on mostly algae and organic detritus found on compacted sand and rock bottoms. They form small groups and are often observed schooling with ocean tangs (A. bahianus) as they feed on algae. During feeding, doctorfish tend to hand their heads down while picking at the algae with its specialized teeth. Since the fish swallows its food whole, it must depend on a unique adaptation for breaking up the food into smaller pieces. It has a gizzard-like organ in the intestine that is partially filled with sand particles. This organ apparently helps the fish to grind up food prior to digestion.

The doctorfish is preyed upon by large piscivorous fishes including tunas.

Source: Florida Museum of Natural History

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Critiques [Translate]

Hello Alfredo,
This is a good size posting to see the closeness of the doctorfish!
perfect sharpness, beautiful colouration and details
well done and TFS
all the best

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