Smallmouth bass
The drainage basin of Chillisquaque Creek is designated as a Warmwater Fishery and a Migratory Fishery. The creek was observed by A. Joseph Armstrong to lack trout. In 1986, the creek was not being stocked. However, it was stocked with black bass, sunfish, and yellow perch in 1934 and with yellow perch in the spring of 1936. In 1986, it contained many of the species found in the West Branch Susquehanna River, including rock bass. Smallmouth bass have also been observed in the creek. Disease is moderately common among young-of-the-year smallmouth bass in the creek. 2011 was the first year where diseased smallmouth bass were documented in the creek since studies began in 2009.