The Species Status Assessment framework is an analytical approach developed by the U.S. Fish & Wildlife Service to deliver foundational science for informing all Endangered Species Act (ESA) decisions. An SSA is a focused, repeatable, and rigorous scientific assessment. The result will be better assessments, improved and more transparent and defensible decision making, and clearer and more concise documents. The Service is already seeing benefits from this approach.

Ideally, the SSA is conducted at or prior to the candidate assessment or 12-month finding stage, but can be initiated at any time. The SSA is designed to “follow the species” so that information on the biological status is available for conservation use and can be updated with new information. Thus, the SSA provides a single source for species’ biological information needed for all ESA decisions (e.g., listing, consultations, grant allocations, permitting, habitat conservation plans, and recovery planning). The biological analysis and the resulting stand-alone science-focused assessment allow for engagements by states and other partners in the science used to base ESA decisions. Early identification of influences on the species’ condition affords timely opportunities to work with partners to implement conservation efforts in advance of potential ESA decisions.

An SSA begins with a compilation of the best available information on the species life history, habitat and taxonomy. Next, an SSA describes the current condition of the species’ habitat and demographics, and the probable explanations for past and ongoing changes in abundance and distribution within the species’ range. Last, an SSA forecasts the species’ response to probable future scenarios of environmental conditions and conservation efforts.

Overall, an SSA uses the conservation biology principles of resiliency, redundancy, and representation (collectively known as the “3 Rs”) to evaluate the current and future condition of the species. As a result, the SSA characterizes a species’ ability to sustain populations in the wild over time based on the best scientific understanding of current and future abundance and distribution within the species’ ecological settings.

An SSA is a biological risk assessment to aid decision makers who must use the best available scientific information to make policy decisions under the ESA. The SSA provides decision makers with a scientifically rigorous characterization of a species’ status that and the likelihood that the species will sustain populations, along with key uncertainties in that characterization. The SSA does not result in a decision directly, but it provides the best available scientific information to guide ESA decisions.

More on Species Status Assessments


Species Status Assessment Framework

The Species Status Assessment (SSA) Framework is an analytical approach developed by the U.S. Fish and Wildlife Service (Service) to deliver foundational science for informing all Endangered Species Act (ESA) decisions. An SSA requires integration of comprehensive project planning; clear roles...

Species Status Assessment Fact Sheet

The Species Status Assessment was developed to enhance conservation success under the Endangered Species Act (ESA). This framework is based on the best available scientific and commercial information, and it delivers the foundational science for informing all ESA decisions. This document...


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