Sticklebacks are small, scaleless fishes with several isolated dorsal spines along the back followed by a dorsal fin. These fishes are well-known for their mating behavior and nest-building abilities.

brook stickleback--Culaea inconstans
threespine stickleback--Gasterosteus aculeatus [nonnative]
ninespine stickleback--Pungitius pungitius