Poecilia catenata Storer, 1846 The northern studfish (Fundulus catenatus) is among the largest of the killifish[citation needed] and is native to the southcentral United States.

[3] Live bait buckets and releases of aquarium pets have caused expansion of the native distribution of this species.

[citation needed] Northern studfish are egg layers and prefer clear, shallow pools and rocky creeks that have a mixed sand/gravel substrate and constant, sluggish flow.

[5] Causes for declining numbers in some areas range from introduction of aggressive non native fish species like the mosquitofish (Gambusia spp.

Current management practices are to plant riparian zones in order to stabilize the streambanks and control run off from agriculture and construction projects.