SUPPLEMENTARY INFORMATION:

Background

On June 2, 1997, we and FWS (jointly, the Services) received a petition from the Biodiversity Legal Foundation requesting us to list Atlantic sturgeon ( Acipenser oxyrinchus oxyrinchus), in the United States where it continues to exist, as threatened or endangered under the Endangered Species Act (ESA) and to designate critical habitat within a reasonable period of time following the listing. A notice was published in the Federal Register on October 17, 1997, stating the Services had determined substantial information existed indicating the petitioned action may be warranted (62 FR 54018). The ESA requires the Services to make listing determinations based on the best scientific and commercial information available after conducting a review of the status of species and after taking into account efforts to protect the species.

On September 21, 1998, after completing a comprehensive status review, the Services published a 12-month determination in the Federal Register announcing that listing was not warranted at that time (63 FR 50187). On the same date, Atlantic sturgeon were retained on the NMFS candidate species list (63 FR 50211; subsequently changed to the Species of Concern List (69 FR 19975; April 15, 2004)). Concurrently, the Atlantic States Marine Fisheries Commission (ASMFC) completed Amendment 1 to the 1990 Atlantic Sturgeon Fishery Management Plan that imposed a 20-40 year moratorium on all U.S. Atlantic sturgeon fisheries until the Atlantic Coast spawning stocks could be restored to a level where 20 subsequent year classes of adult females were protected (ASMFC, 1998). In 1999, pursuant to section 804(b) of the Atlantic Coastal Fisheries Cooperative Management Act (16 U.S.C. 5101 et seq.), we followed this action by closing the Exclusive Economic Zone to Atlantic sturgeon retention.

In 2003, we sponsored a workshop with ASMFC and FWS on the “Status and Management of Atlantic Sturgeon” in Raleigh, North Carolina, to discuss the current status of sturgeon along the Atlantic Coast and determine what obstacles, if any, were impeding the recovery of Atlantic sturgeon (Kahnle et al., 2005). The results of the workshop reported “mixed” reviews where some populations seemed to be recovering while others were declining. Bycatch and habitat degradation were noted as possible causes for some population declines.Based on the information gathered by the participants during the 2003 workshop on Atlantic sturgeon, we decided that a second review of Atlantic sturgeon status was needed to determine if listing as threatened or endangered under the ESA was warranted. In 2006, we convened a SRT to conduct a thorough review of the status of the species.

The 2007 Status Review Report

On February 23, 2007, the SRT finalized its report on the status of Atlantic sturgeon (Status Review for Atlantic Sturgeon ( Acipenser oxyrinchus oxyrinchus)). The status review report was also reviewed and supplemented by eight state and regional experts who provided individual expert opinions on the information contained in the status review report and provided additional information to ensure the report provided the best available data. Lastly, the report was peer reviewed by six experts from academia and received favorable reviews. The final report incorporates edits and information in light of this peer review and the expert reviews. Consistent with the February 7, 1996, joint FWS and NMFS Distinct Vertebrate Population Segment Policy (61 FR 4722), the SRT concluded that Atlantic sturgeon populations should be divided into five distinct population segments (DPSs). The five DPSs were named: (1) Gulf of Maine, (2) New York Bight, (3) Chesapeake Bay, (4) Carolina, and (5) South Atlantic. These Atlantic sturgeon DPSs were discrete because they were markedly separated from each other based on physical, genetic, and physiological factors. They were also significant to the species because they: (1) were located in a unique ecological setting; (2) had unique genetic characteristics; and (3) would represent a significant gap in the range of the taxon if any one of them were to become extirpated. Canadian populations were considered to be discrete from the Gulf of Maine DPS because there were significant differences in control of exploitation and regulatory mechanism for the populations (i.e., still support a commercial fishery). Further support for discreteness between Canadian populations and the Gulf of Maine DPS was the marked separation between them based on genetic, physiological, and habitat features. Therefore, Canadian populations were not included in the Gulf of Maine DPS, and they were not considered further in the status review report.

The SRT evaluated the status of Atlantic sturgeon DPSs by analyzing the impacts of the factors listed in section 4(a)(1) of the ESA on each subpopulation within each DPS and considering whether the subpopulations constituted significant portions of the range of each DPS. The SRT identified 15 stressors within these factors and ( printed page 15866) summarized their impacts on Atlantic sturgeon using a semi-quantitative extinction risk analysis (ERA), similar to that used by other status review reports. Of the stressors evaluated, bycatch mortality, water quality, lack of adequate state and/or Federal regulatory mechanisms, and dredging activities were most often identified as the most significant threats to the viability of Atlantic sturgeon subpopulations. Additionally, some subpopulations were impacted by unique stressors, such as habitat impediments (e.g., Cape Fear and Santee-Cooper rivers) and apparent ship strikes (e.g., Delaware and James rivers).

The SRT used the ERA to conclude that three of the five DPSs (New York Bight, Chesapeake Bay, and Carolina) were likely (>50 percent chance) to become endangered in the foreseeable future, which was defined as 20 years. The remaining DPSs (Gulf of Maine and South Atlantic) were found to have a moderate risk (<50 percent chance) of becoming endangered in the next 20 years. The ERA of these two remaining DPSs suggested that the DPSs do not warrant listing, though the available science may not be sufficient to allow a full assessment of these DPSs.

Currently, we are considering the information presented in the final status review report, the comments from the peer reviewers, and the response of the SRT to the peer reviewers to determine if action under the ESA is warranted. A decision regarding our listing determination will be published in the Federal Register .

Authority

The authority for this action is the ESA, as amended (16 U.S.C. 1531 et seq.).