The state may regulate fishing by non-Indians to achieve a wide variety of management or "conservation" objectives. Its selection of regulations to achieve these objectives is limited only by its own organic law and the standards of reasonableness required by the Fourteenth Amendment. But when it is regulating the federal right of Indians to take fish at their usual and accustomed places it does not have the same latitude in prescribing the management objectives and the regulatory means of achieving them. The state may not qualify the federal right by subordinating it to some other state objective or policy. It may use its police power only to the extent necessary to prevent the exercise of that right in a manner that will imperil the continued existence of the fish resource.