Amphihaline species making important migrations. Spends its adult life in the sea for about 20 to 30 months. Adults enter freshwater/estuaries for spawning in spring; after spawning they normally die (Ref. 51442). The larvae are reported to spend 6-8 years in the substrate followed by metamorphosis and movement to sea. They remain in the estuarine/marine environment for a juvenile feeding period lasting 23-28 months, during which they grow from ca. 4 to 900 g; at the end of this period, they move into rivers as adults and reproduce (Ref. 58185). Larvae live in rivers where they feed on microorganisms and detritus (Ref. 30578, Ref. 51442). During juvenile feeding phase, they may not only feed on dead or netted fish, but also attach themselves to healthy fish (e.g. wide variety of bony fishes, sharks and marine mammals) by scraping a hole in their skin and sucking out the blood, body fluids and flesh. Adults are hematophageous predators of fishes (Ref. 51442). The ammocoetes-larvae is microphageous feeding mostly on diatoms (Ref. 51442).