Components of a Biological Opinion

A biological opinion is the document prepared by NOAA Fisheries or USFWS (referred to commonly as the Services) as part of the formal consultation process, to be issued at the culmination of this consultation process. This chapter provides a brief overview of the components of a biological opinion.

In general, a biological opinion is required when an action (e.g., construction activity) is estimated to adversely affect an ESA-listed plant or animal species. Depending upon the species in question, NOAA Fisheries or USFWS issues a biological opinion on the effects of the proposed action on the affected ESA-listed species. If the agency concludes that the species will be unaffected, the proposed action receives a no-jeopardy biological opinion and continues as planned. If the proposed action is found to jeopardize a species, the federal government may propose alternatives, require additional mitigation measures or deny the project. If the proponent can modify the project to align with proposed alternatives and/or satisfy the recommended mitigation requirements, the proposed action can proceed.