On August 17, 2017, the National Marine Fisheries Service (NMFS) published in the Federal Register a final rule designating over 3,900 river miles along the east coast as critical habitat for five distinct population segments (“DPS”) of Atlantic Sturgeon (New York Bight, Chesapeake Bay, Carolina, South Atlantic and Gulf of Maine). The agency chose these areas based on the presence of “physical or biological factors” (PBFs) essential for the conservation of the species and that may require special management considerations or protection. Back in 2012, NMFS had listed each of the five Atlantic Sturgeon DPS as either endangered or threatened. 77 Fed. Reg. 5880; 77 Fed. Reg. 5914. Once a species is listed, the relevant agencies must identify critical habitat for the species. Under the ESA, impacts to critical habitat must be evaluated in federal permitting actions, in addition to impacts to the species itself.
Notably, this critical habitat designation incorporates new regulations issued by the NMFS and the Fish and Wildlife Service in early 2016 (described in a blog post here). These regulations instruct the agencies to identify habitats with sufficient PBFs to promote the recovery of a species in addition to its survival. Once a critical habitat is designated, a project’s impacts cannot “appreciably diminish” the PBFs within the habitat.
In the rule, NMFS defines the conservation objectives for all five DPSs. These conservation objectives include facilitating increased survival of sturgeon in all life stages, promoting adult reproduction, and increasing juvenile and subadult growth into the adult population. The objectives are supported by protecting specific PBFs tailored for the different populations of the sturgeon. Any project affecting the Atlantic sturgeon’s critical habitat must avoid altering the identified PBFs. For example, for the Carolina and South Atlantic DPSs, NMFS defined five PBFs necessary for the recovery of the species:
- Hard bottom substrate in low salinity waters;
- Transitional salinity zones inclusive of waters with a gradual downstream gradient and soft substrate;
- Waters of appropriate depth and absent physical barriers to passage (e.g. dams, reservoirs, etc.) between the river mouths and spawning sites necessary for support; and
- Water quality conditions, especially in the bottom meter of the water column, between the river mouths and spawning sites with appropriate temperature and oxygen values.
In a significant departure from the proposed rule, NMFS exercised its discretion under Section 4(b)(2) of the ESA not to designate certain unoccupied areas as critical habitat, concluding that “the benefits of exclusion (that, is avoiding some or all of the impacts that would result from designation) outweigh the benefits of designation.” 82 Fed. Reg. 39229.
The specific areas designated as critical habitat for the Carolina and South Atlantic DPS can be found at this link.