Triggerfish

Triggerfishes are about 40 species of often brightly colored fishes of the family Balistidae. Often marked by lines and spots, they inhabit tropical and subtropical oceans throughout the world, with the greatest species richness in the Indo-Pacific. Most are found in relatively shallow, coastal habitats, especially at coral reefs, but a few, such as the aptly named oceanic triggerfish are pelagic. While several species from this family are popular in the marine aquarium trade, they are often notoriously ill-tempered.Triggerfish males migrate to their traditional spawning sites prior to mating and establish territories. Some male species build hollow nests within their territories.Triggerfish males are fierce in guarding their territories as having a territory is essential for reproduction. A male's territory is used for spawning and parental care. Most male territories are located over a sandy sea bottom or on a rocky reef. A single territory usually includes more than one female, and the male mates with all of the females residing in or visiting his territory . In Hachijojima, Izu Islands, Japan, one male crosshatch triggerfish  has up to three females in his territory at the same time, and mates with them in pairs. Each male red-toothed triggerfish mates with more than ten females in his territory on the same day. Yellow margin triggerfish  also exhibit polygyny mating.
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