By Koaw 2023,

My data was primarily compiled just to ensure that former trends observed in other studies could be confirmed as reliable, particularly as it pertained to the pickerels. The last chart at the bottom is an amalgamation of various studies for all species and most hybrids, including some of my data that found outliers not listed in other studies.

NOTES ON MEASUREMENTS FOR KOAW’S DATA CHARTS:

SL – STANDARD LENGTH: This is straight line measurement from the most anterior portion of the fish, of which, is the lower jaw on species of Esox, to the most posterior portion of the caudal peduncle where the fleshy tissue ends, not necessarily from the last hypural bone.

PtOL/SnL P2P: The postorbital length of the head (PtOL) for point to point measurements (P2P) are taken from the most posterior portion of the orbital rim to the most posterior portion of the bony operculum. The SnL is taken from the most anterior portion of the upper lip. These will not necessarily be parallel to how standard length is measured.

PtOL/SnL ST: Both of these measurements PtOL and SnL are taken parallel to how the standard length measurement is taken. The PtOL is from the most posterior portion of the orbital rim to the most posterior portion of the bony operculum. The SnL is taken from the most anterior portion of the upper lip.

PORB2DFO/SL: The distance from the posterior edge of the orbit to the dorsal fin origin (PORB2DFO) is taken as a parallel measurement to the standard length. This is a straight line measurement from the most posterior portion of the orbital rim to the most posterior portion of the caudal peduncle where the fleshy tissue ends, not necessarily from the last hypural bone.

MAIN REFERENCES FOR ALL SPECIES/HYBRIDS CHART

Black, J. D., & Williamson, L. O. (1946). Artificial hybrids between muskellunge and northern pike. Trans. of the Wisc. Aca. of Sci., 38, 299-314.
Casselman, J. M., Crossman, E. J., Ihssen, P. E., Reist, J. D., & Booke, H. E. (1986). Identification of Muskellunge, Northern Pike, and their Hybrids. Am. Fish. Soc. Spec. Publ., 15, 14-46.
Crossman, E. J. (1962). The Redfin Pickerel, Esox a. americanus in North Carolina. Copeia, 1962(1), 114-123.
Crossman, E. J. (1966). A Taxonomic Study of Esox americanus and Its Subspecies in Eastern North America. Copeia, 1, 1-20. doi:https://doi.org/10.2307/1440756
Crossman, E., & Buss, K. (1965). Hybridization in the Family Esocidae. J. Fish. Res. Bd., 22(5).
Eddy, S. (1944). Hybridization between Northern Pike (Esox lucius) and Muskellunge (Esox masquinongy). Jour. of the Minn. Acad. of Sci., 12(1), 38-43.
Koaw. (2023). Select Morphometrics and Meristics of Esocids. Koaw Nature - KNFS. Retrieved from http://www.koaw/org/esoxdatakoaw
Raney, E. C. (1955). Natural hybrids between two species of pickerel (Esox) in Stearns Pond, Massachusetts. Supp't to Fish. Rept. for some central, eastern and western Mass. lakes, ponds and reservoirs, 1951-1952.