Tilapia
Oreochromis niloticus
Type: freshwater, brackish
Physical Characteristics
Deep-bodied, laterally compressed with a long dorsal fin. They have cycloid scales and a distinctive vertical barring on their bodies and tail fins. Coloration is typically grey or brownish to silver, often with darker vertical bands.
Habitat & Distribution
Native to Africa and the Middle East but widely introduced globally. They prefer shallow, warm waters in lakes, rivers, and ponds, and are highly tolerant of brackish water and low dissolved oxygen levels.
Size & Weight
Commonly 20-30 cm, but can reach up to 60 cm. Max weight is approximately 4.3 kg (9.5 lbs).
Similar Looking Species
Blue Tilapia (Oreochromis aureus) and Mozambique Tilapia (Oreochromis mossambicus). Nile Tilapia are distinguished by the regular vertical stripes on their caudal (tail) fin.
Ecological Role
Primary consumers that help control algae and aquatic vegetation. In areas where they are invasive, they often outcompete native species for food and nesting sites.
Diet
Omnivorous, primarily feeding on phytoplankton, periphyton, aquatic macrophytes, and occasionally small invertebrates.
Behavior
Diurnal and often social, forming schools during the day. Males are highly territorial during breeding seasons and will defend nesting sites excavated in the substrate.
Reproduction
Mouthbrooders; after spawning, females carry eggs and fry in their mouths for protection. This allows them to reproduce successfully in environments with high predator pressure.
Conservation Status
Least Concern (IUCN); population is stable and expanding globally due to introductions.
Identification Tips
Look for the interrupted lateral line, the long dorsal fin with sharp spines, and the prominent vertical bars on the tail fin.
Interesting Facts
Tilapia can survive in water temperatures up to 40 degrees Celsius and are known for their extreme adaptability to varying water qualities, including high salinity.
Identified on: 5/23/2026
Mode: Standard