Crescent Grunter

Terapon jarbua 

Habitat & Distribution :  Indo-Pacific Ocean 

Diet : Smaller fish, crustaceans, plants, insects 

Size : 36 cm 

Lifespan : 5-10 years

Description

The crescent grunter can be recognized by its concentric circle pattern, which can be seen from above, resembling a target. This fish is catadromous, meaning it migrates from freshwater to saltwater. 

Behavior

The crescent grunter likes to eat fish scales. These fish are scale nibblers, a behavior thought to originate from a modification of predation and parasite removal. 

Reproduction

The crescent grunter is a catadromous species, meaning adults live in fresh or brackish water but must return to the sea to spawn. They are oviparous that reproduce in deeper, high-salinity marine waters. 

Communication & Perception

Crescent grunters communicate primarily by producing audible grunting sounds using specialized muscles that vibrate their swim bladder. These sounds are used to communicate with other fish, especially when they are threatened 

Predator(s)

Sharks, crocodiles, birds, larger predatory fish