Definitions for "Species of Concern"
species about which NMFS has some concerns regarding status and threats, but for which insufficient information is available to indicate a need to list the species under the ESA. This may include species for which NMFS has determined, following a biological status review, that listing under the ESA is "not warranted," pursuant to ESA section 4(b)(3)(B)(i), but for which significant concerns or uncertainties remain regarding their status and/or threats. Species can qualify as both "species of concern" and "candidate species."
species for which population viability is a concern but no scientific information is available to support a listing proposal. Species of concern experience current or predicted downward trends in population numbers or density, or significant current or predicted downward trends in habitat capacity that would reduce a species' existing distribution
a species that scientists feel might be threatened or that could become threatened but for which there is little data or research available