Sticklebacks

Sticklebacks are small, scaleless fish with spines in front of the dorsal (back) fin. They grow to approximately 2 to 4 inches.

What species of sticklebacks live in the Chesapeake Bay?

Two species of sticklebacks can be found in the Chesapeake Bay:

• The threespine stickleback, Gasterosteus aculeatus, varies in color from gray to olive brown, with black speckles all over its body and bony plates running along its sides. It has three dorsal spines: two that are large and one that is small.
• The fourspine stickleback, Apeltes quadracus, varies in color from brownish-green to black, with dark, mottled patterns and no bony scutes. It has three large dorsal spines and a fourth that is attached to the dorsal fin. Fourspines are a bit smaller than threespines.

Where do sticklebacks live?

Sticklebacks are mostly found in shallow, vegetated areas of the Chesapeake Bay, along with pipefish and lined seahorses.

• Threespine sticklebacks visit the Chesapeake Bay during winter and spring, moving as far north as Kent Island.
• Fourspine sticklebacks are year-round residents of the entire Chesapeake Bay. They move to the Bay's deeper channels  in the winter.

What do sticklebacks eat?

Sticklebacks mainly feed on tiny crustaceans.

How do sticklebacks reproduce?

Threespine sticklebacks are anadromous, spawning from late February through September in the fresh to brackish waters of western shore rivers.

• The male threespine builds a ball-shaped nest in the soft, muddy bottom.
• The female threespine lays 75 to 100 eggs in the nest.
• The male guards the eggs until they hatch and the young sticklebacks are able to take care of themselves.

Fourspine sticklebacks spawn in late April and early May among bay grass beds along the Bay's shoreline.

• The male fourspine uses grasses and weeds to build a cup-shaped nest that is held together by a thread-like secretion. One or more females lay eggs into the nest.
• The protective male fourspine guards the eggs and young for several weeks, keeping the nest clean and attacking other fish that swim too close.

Other facts about sticklebacks:

• Sticklebacks can live for one to three years.
• During breeding, male threespines have a reddish belly and male fourspines have bright red pelvic fins.