What is Free Fishery?

Legal Definition
A franchise in the hands of a subject, existing bj grant or prescription, distinct from 'an ownership in the soil. It is an exclusive right, and applies to a public navigable river, without any right in the soil. 3 Kent, Comm. 410. Arnold v. Mundy, 6 N. .J. Law, 87, 10 Am. Dec. 356. See Albright v. Sussex County Lake & Park Com'n. 68 N. J. Law, 523, 53 Atl. 612; Brook-haven v. Strong, 60 N. Y. 64.
-- Black's Law Dictionary
Legal Definition
The exclusive right of fishing in a public river.
-- Ballentine's Law Dictionary