The Endangered Species Act (ESA) charges the National Marine Fisheries Service (a federal agency) with the duty to "ensure" that any proposed action by the council does not "jeopardize" any threatened or endangered species. The Steller sea lion is on the list of endangered species. The agency developed a North Pacific marine fishery plan that permitted a significant harvest of fish by commercial fisheries in the area. Greenpeace, an environmental group, challenged the agency on the grounds that the plan was not based on a sufficient number of biological studies on the impact of the allowed fishing on the Steller sea lion. Greenpeace's biologic opinion concluded that the fishery plan would reduce the level of food for the sea lions by about 40% to 60% if the juvenile fish were not counted in that figure. Greenpeace's expert maintained that counting juvenile fish was misleading because they were not capable of reproducing and the government agency's figure was, as a result, much lower at 22% [Greenpeace, American Oceans Campaign v. National Marine Fisheries Service, 237 F. Supp. 2d 1181 (W.D. Wash.)]. What would Greenpeace need to show to be successful in challenging the agency's fishery plan? What would be their next step(s)? Provide a rationale or explain how you came to this determination.

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