U.S.-Canadian management of marine migratory species is a particularly rich place to understand the complex relationship between migratory science, conservation, and law. The two nations share a large border, have a long-lasting historic friendship, and already collaborate extensively. However, the relationship is not without contention. The substantial economic interests in the oceans and differences in governance structure have not infrequently frustrated efforts at cooperative management.

On August 29, 2023, the U.S. Environmental Protection Agency and the U.S. Army Corps of Engineers issued a direct final rule that revised the “waters of the United States” (WOTUS) definition rule. This rule amended the final WOTUS rule, previously published in January 2023, to be consistent with the Supreme Court’s May decision in Sackett v. Environmental Protection Agency. On September 14, the Environmental Law Institute hosted a panel of experts to analyze the new rule and discuss its regulatory and policy consequences.