Threespine sticklebacks vary in color from gray to olive to brown, with black speckles all over. They have bony plates running along their sides and three spines on their back. (N Sloth/Biopix)
Sticklebacks are small, scaleless fish with spines along their back in front of their dorsal fin.
Two species of sticklebacks can be found in the Chesapeake Bay:
Threespine stickleback, Gasterosteus aculeatus
Fourspine stickleback, Apeltes quadracus
Appearance:
Threespine sticklebacks vary in color from gray to olive to brown, with black speckles all over. They have bony plates running along their sides.
Fourspine sticklebacks vary in color from brownish-green to black with dark, mottled patterns. They have a bony ridge on either side of the abdomen.
Threespines have three spines on their back (two large and one small). Fourspines have four spines on their back (three large and one that is attached to the dorsal fin).
Grow to 2-4 inches. Fourspines are a bit smaller than threespines.
Habitat:
Found mostly in shallow, vegetated areas near the Bay’s shoreline
Fourspine sticklebacks move to deeper channels in winter
Range:
Threespine sticklebacks visit the Bay during winter and spring, venturing as far north as Kent Island, Maryland
Fourspine sticklebacks are found throughout the Bay year-round
Feeding:
Mainly eat tiny crustaceans
Predators:
Larger fish
Reproduction and Life Cycle:
Threespine sticklebacks are anadromous, spawning from late February-September in the fresh and brackish waters of the Bay’s western shore rivers
Male threespines develop a reddish belly during breeding
The male builds a ball-shaped nest of leaves in the soft, muddy bottom, into which the female lays 75-100 eggs
The male cares for the eggs until they hatch and the young are able to take care of themselves
Fourspine sticklebacks spawn in late April-early May among bay grasses beds near the shoreline
Male fourspines have bright red pelvic fins during breeding
The male uses grasses and weeds to build a cup-shaped nest
One or more females lays eggs into the nest
The protective male guards the eggs and young for several weeks, keeping the nest clean and attacking other fish that swim too close
Sticklebacks can live for 1-3 years
Other Facts:
One of the most scientifically studied non-game fishes
Sources and Additional Information:
Fishes of Chesapeake Bay by Edward O. Murdy, Ray S. Birdsong and John A. Musick
