Mille Lacs Lake, one of Minnesota’s over 13,000 lakes, holds a reputation for being one of the best walleye fisheries in Minnesota, as well as being a fishing destination for anglers across the nation. In 1999 the Supreme Court held that the Mille Lacs Band of Chippewa Indians retained hunting and fishing rights on ceded land that were granted to them in the 1837 Treaty of St. Peters. Part of this ruling allowed the Mille Lacs tribe to continue their commercial walleye fishing operation on Mille Lacs Lake. Since the Supreme Court’s ruling, the walleye population on Mille Lacs Lake has been declining. In 2013, the Minnesota DNR released reports showing that the walleye population in Mille Lacs has reached a forty-year low. This article explores the various causes of the fishery decline since 1999, specifically focusing on the effects of continued enforcement of the 1837 Treaty. Following an overview of Native American treaty formation and interpretation canons, this article discusses the Supreme Court’s holding in Minnesota v. Mille Lacs Band of Chippewa Indians. The article proposes that native commercial harvesting is the main cause of the decline in the Mille Lacs Lake fishery. Section III of the article explores how the State of Minnesota is able to regulate Native American fishing rights under current treaty interpretation when regulation is “reasonably necessary.” Finally, the article discusses the inherent problems that accompany regulation of Native American rights. Though this article proposes that drastic measures must be taken in order to save the Mille Lacs fishery, these drastic measures must respect the sovereignty of the Mille Lacs Band of Chippewa.