Alligator Gar

Species Profile

• Scientific Name: Atractosteus spatula
• Common Name: Alligator Gar
• Adult Size: Up to 10 feet (3 meters), though typically 4–6.5 feet (1.2–2 meters) in captivity
• Life Expectancy: 50–70 years in the wild; 20–30 years in captivity
• Habitat: Slow-moving rivers, bayous, estuaries, and lakes with abundant vegetation; can tolerate brackish and freshwater

Tank Requirements

• Minimum Tank Size: 500+ gallons for juveniles; ponds or custom tanks for adults
• Ideal Temperature: 75–86°F (24–30°C)
• pH Range: 6.5–8.0
• Water Hardness: 5–20 dGH
• Temperament: Semi-aggressive; predatory toward smaller fish but generally non-aggressive toward tank mates of similar size

Diet & Nutrition

• Omnivorous: Primarily carnivorous

  • Diet: Fish, crustaceans, amphibians, small mammals and birds in the wild; in captivity, feed whole fish, shrimp, and occasionally carnivore pellets

Appearance

• Long, torpedo-shaped body
• Olive-brown to gray-green coloration on the back with a lighter underside
• Tough, ganoid scales that resemble armor
• Two rows of large, sharp teeth in the upper jaw

Distinctive Features

• Broad, alligator-like snout (hence the name)
• Can breathe both air and water via a specialized swim bladder
• Considered a "living fossil" due to ancient lineage dating back over 100 million years