Spotted Scat

The Spotted Scat (Scatophagus argus) is the type species of the family Scatophagidae, a small group of deep-bodied, disc-shaped fishes native to the Indo-Pacific. It occurs from the Persian Gulf and East Africa through South and Southeast Asia to northern Australia and the western Pacific, typically in coastal and estuarine waters. Spotted Scat are hardy, adaptable fish able to tolerate a broad range of salinities, from nearly fresh water to full-strength seawater, which allows them to occupy diverse habitats from river mouths to open harbors. They are widely kept in aquariums for their bold spotted pattern and are common and secure throughout their natural range.

Spotted Scat have a deep, almost square or disc-like body strongly compressed from side to side, reaching 20-38 cm in length.

Distinguishing features:

• Olive-green, brown, or silvery-gray background color
• Numerous irregular dark spots scattered across the body and fins, denser in juveniles and often fading with age
• Tall, spiny first dorsal fin that can be raised defensively
• Small, terminal mouth with a steep forehead profile
• Rounded caudal fin

Spotted Scat can be told apart from the Green Scat color form by having a more silvery-olive base tone with denser black spotting rather than a uniform green-toned body.

Spotted Scat are native to coastal and estuarine waters of the Indo-Pacific, ranging from the Persian Gulf and East Africa through South and Southeast Asia to northern Australia and parts of the western Pacific. They are highly euryhaline, found across a wide salinity gradient from brackish mangrove creeks and river mouths to fully marine harbors and reef flats, and occasionally venture into freshwater reaches of rivers. Spotted Scat favor turbid, nutrient-rich water near mangroves, seawalls, and other structure that provides shelter and a supply of food.

Spotted Scat are loosely social fish, often found in small groups foraging near the bottom or around structure such as mangrove roots and pilings. They are opportunistic omnivores, grazing on algae, detritus, small invertebrates, and organic matter, and are known to feed near nutrient-rich areas in the wild. When threatened, Spotted Scat can erect their spiny dorsal fin as a defense against predators. They show considerable tolerance for fluctuating salinity and water quality, allowing them to thrive in disturbed estuarine habitats. Spawning takes place in marine or higher-salinity waters, with pelagic eggs and larvae later moving into estuarine nurseries to mature.