Porcupine fish
Porcupine fish are tropical fish belonging to the family Diodontidae, named for their resemblance to land porcupines due to their spiny bodies. These fish inhabit coral reefs in tropical and subtropical waters, with over 20 species ranging in size from 1 to 3 feet (30 to 90 centimeters). They are characterized by a brown or olive-green coloration with pale undersides and dark spots, and are covered in sharp, two-inch spines that provide them with armor-like protection. When threatened, porcupine fish can inflate their bodies with air or water, transforming into round, spiny balls that deter predators like sharks and barracudas. Some species possess toxins in their skin and livers, which can be lethal to humans and contribute to their consumption in culinary dishes like fugu in Japan and butete in the Philippines, prepared by specially trained chefs. Porcupine fish primarily feed on mollusks and corals, utilizing their strong jaws to break through hard shells, though this feeding behavior can be destructive to coral reefs. They are solitary creatures, typically living near the ocean floor, and reproduce by releasing eggs into open water, where fertilization occurs. The lifespan of porcupine fish can reach around 10 years in captivity.
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Porcupine fish
The family of porcupine fish receives its name from its similarities to the land mammal, the porcupine. These tropical fish are small, but predators such as sharks, barracudas, and birds usually leave them alone. When threatened or attacked, porcupine fish fill their bodies with air or water, swelling into round, spiny balls. Some species have poison in their skin and livers.
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Tetraodontiformes
Family: Diodontidae
Genus: Various (see below)
Species: Various (see below)
The coral reefs of tropical and subtropical waters are home to over 20 species of porcupine fish. They are named after porcupines that live on land and share similar spines. These fish are between 1 and 3 feet (30 to 90 centimeters) long. They may be brown or olive-green with pale undersides and, dark-spotted, rounded bodies. Many sharp, two-inch (five-centimeter) spines cover their bodies from head to tail. The small pectoral fins behind their heads are light in color and fan-like, as are their dorsal (back), anal (rear), and caudal (tail) fins. They look similar to pufferfish but their spines are always visible.
The porcupine fish's small fins are not very strong, and they may be swept into temperate waters by ocean currents. The fish swim slowly and can maneuver with ease in any direction. The fish do not swim in schools, or groups, but feed and live alone near the bottom of shallow waters.
The porcupine fish's spines take the place of scales and give the fish tough armor-like protection. The presence of predators or other threats causes a sudden change in the fish's appearance. The fish fill their bodies with water, which causes them to swell in size into dangerous, round, spiny balls. This makes the fish nearly impossible for predators to swallow. If predators do swallow porcupine fish, they may die from injuries caused by the spines. Sharks and barracudas have died with porcupine fish stuck in their throats.
Another means of defense is the toxin, or poison, inside the porcupine fish's skin and livers. This poison is strong enough to kill a human. Despite the danger, porcupine fish is eaten in Japan and the Philippines, called fugu in Japan and butete in the Philippines. Specially trained chefs prepare the fish to remove the poison. Even so, people die from consuming the fish. Porcupine fish have little other commercial value. Some people catch and dry them when they are puffed to sell as souvenirs to tourists.
Coral reefs provide porcupine fish with mollusks, such as clams, snails, sea urchins, oysters, marine worms, and corals. The fish have strong jaws and beak-like mouths with plates of teeth that can bite through the hard shells and corals. The teeth grind the rock-like corals into sandy powder, which they swallow with the creatures that live in the corals. The creatures are digested, and the coral powder leaves the body with other waste products. Such feeding habits are destructive to the coral reefs.
It is believed that female porcupine fish spawn in open water. This means they release large quantities of eggs into the water, and the males swim by to fertilize the eggs. The eggs float and hatch about 2 days later. The young fish begin life as planktonic larvae and drift in the sea's current until they mature.
The life span of porcupine fish is around 10 years in captivity.
Porcupine fish are closely related to the puffer fish in the family Tetradontidae.
Species include:
Balloonfish, or spiny puffer fish Diodon holocanthus
Bridled burrfish Chilomycterus antennatus
Birdbeak burrfish Cyclichthys orbicularis
Deepwater burrfish Allomycterus pilatus
Four-bar porcupinefish Lophodiodon calori
Long-spined porcupinefish Diodon hystrix
Longspine burrfish Tragulichthys jaculiferus
Striped burrfish Chilomycterus schoepfii
Three-bar porcupinefish Dicotylichthys punctulatus
Bibliography
Baker, Amber, and Ashley Koser. "Diodon Hystrix." Animal Diversity Web, animaldiversity.org/accounts/Diodon‗hystrix. Accessed 15 Apr. 2024.
"Porcupinefish." National Aquarium, aqua.org/explore/animals/porcupinefish. Accessed 15 Apr. 2024.
"Porcupinefish." National Geographic Society, www.nationalgeographic.com/animals/fish/facts/pufferfish. Accessed 15 Apr. 2024.