puffers

Puffers are a diverse group of fish, most commonly associated with the family Tetraodontidae, though related groups such as porcupinefishes (Diodontidae) share the inflation defense. They are best known for their ability to inflate their bodies when threatened, becoming rounder and more difficult for predators to swallow. Some species also bear spines that protrude when inflated.

Anatomy and defense: Puffers typically have a small mouth with beak-like teeth formed by fused plates, and a robust, rounded body. When alarmed, many puffers rapidly ingest water or air to inflate. In several species, spines become erect on the inflated body, enhancing deterrence. A notable feature of many puffers is their toxin, tetrodotoxin, a potent neurotoxin that can be deadly to humans and other predators if ingested. The toxin is often concentrated in the liver, ovaries, intestines, and skin, and is produced by symbiotic bacteria in some species.

Distribution and habitat: Puffers occur in warm and temperate seas worldwide, with a high diversity in tropical regions. They inhabit coastal waters, estuaries, and, in some lineages, freshwater or brackish environments. Species vary widely in size, diet, and behavior, from benthic invertebrate feeders to more omnivorous forms.

Human interactions and aquarium trade: Pufferfish are valued in the aquarium trade for their distinctive shape and behavior, but many species require large tanks and specialized care. Their strong beaks allow them to crush shells and hard prey, and some species can be aggressive toward tankmates. Certain puffers used for consumption, notably in Japanese fugu dishes, pose serious poisoning risks if not prepared by licensed professionals.

Conservation: Statuses vary by species and region, with threats including habitat degradation and overfishing. Some puffers are of least concern, while others face localized declines.