Prefer shallow, brackish waters but also occur in fresh waters (Ref. 36771); in lagoons and lakes, large rivers, harbors, on sand or rock bottom; mostly found on well vegetated or rock bottom (Ref. 59043). Can tolerate a temperature range of 0 to 30°C, but mainly thrive in warm temperate waters; able to tolerate low oxygen content waters for several days (Ref. 36771). Oviparous, with demersal eggs (Ref. 36771). Longevity up to 4 years. Males reproduce for the first time at 3-4 years, females at 2-3 years. Spawning season in April to September; females may repeat spawning during a season, every 18-20 days; body of males entirely black during this season. Adhesive eggs deposited on stones, shells and aquatic plants; males guard eggs until hatching and usually die after spawning season. Egg clutches are supposed to be occasionally transported attached to the hull of ships, facilitating introduction to other areas. Feeds on a wide variety of invertebrates and small fish, mostly on molluscs (Ref. 59043).