In Puyallup Tribe v. Department of Game of Was. (391 U.S. 392, 20 L. Ed. 2d 689, 88 S. Ct. 1725 [1968], the tribe had an off-reservation treaty right to take fish "at all usual and accustomed grounds and stations . . . in common with all citizens of the Territory" (id. at 395). In light of this treaty, the Supreme Court determined that a state regulation prohibiting fixed net fishing could not be enforced against members of the Puyallup Nation absent a finding that the ban represented a " 'reasonable and necessary' conservation measure" (id. at 402). It remanded for consideration of this question, as well as for findings on "the issue of equal protection implicit in the phrase 'in common with' " (id. at 403)