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Northern Puffer

Sphoeroides maculatus

The northern puffer puffs up into a ball in self-defense. (Virginia Institute of Marine Science)
The northern puffer puffs up into a ball in self-defense. (Virginia Institute of Marine Science)

The northern puffer is a club-shaped fish that puffs up into a ball in self-defense. It visits the deep flats of the middle and lower Chesapeake Bay from spring through autumn.


  • Yellow, brown or olive body covered in small prickles
  • Yellow or white belly
  • Puffs up into a ball in self-defense
  • Dark, vertical, splotchy bars on the sides
  • Small, black spots on the back, sides and cheeks
  • Tiny, beak-like mouth
  • Small dorsal fin set far back, near the tail
  • Usually grows 8-10 inches long


  • Bottom-dweller in the Bay’s flats and channel margins


  • Visits the lower to middle Chesapeake Bay from spring through autumn
  • More common in the lower Bay but travels as far north as Love Point on Kent Island
  • Leaves the Bay in winter for deep offshore waters


  • Uses its strong, beak-like mouth to crush the shells of small mollusks, crustaceans and other invertebrates


  • Ability to puff up into a prickly ball deters many predators

Reproduction and Life Cycle:

  • Spawns from May-August in shallow waters near the shore
  • Female lays sticky eggs that attach to the bottom
  • Male guards the eggs until they hatch
  • Little else is known about its life cycle

Other Facts:

  • Puffs up by inhaling air or water into a special chamber near the stomach
  • If caught and thrown back into the water while inflated, a northern puffer will float upside down at the surface for a few moments, then quickly deflate and swim away
  • Although some types of puffers are poisonous, the northern puffer is not. In fact, it is a delicious fish, sold in fish markets as "sea squab."
  • Not an efficient swimmer; swims by moving its tail fin back and forth like a paddle to propel itself forward.

Sources and Additional Information:

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