shark and ulua

Why are predators important?

White tip sharkUlua (giant trevally), alu (barracuda), and malie (sharks), patrol coral reefs for prey. Not only are they catching a meal,  but they are actually helping to keep the reef healthy too. When predators eat weak or sick animals, they make fish populations healthier. Their hunting at the top of the marine food web is crucial to ensuring a balance between herbivores, carnivores, and algae on the coral reef.

Each species on the reef plays an important role within the food web; a change in one species may affect many others. A healthy coral reef supports many top predators such as sharks and groupers. The top predators keep down the numbers of smaller predators that eat the herbivores. If too many herbivores are eaten, the algae would start to grow too fast and smother the coral. If algae overgrows and kills the coral, this means that the other animals that depend on the coral reef cannot survive.

Explore other predator and prey relationships on coral reefs or further explore the connections between mano and Hawaii.


O le sapatu moe ʻese.
— Samoan proverb
The barracuda that sleeps apart.
The barracuda sleeps by itself because the other fish fear and avoid it.