Voglio sapere a riguardo di…

34982

Federal Register / Vol. 86, No. 124 / Thursday, July 1, 2021 / Rules and Regulations
khammond on DSKJM1Z7X2PROD with RULES

unimportant or may not be needed for recovery of the species. Areas that are important to the conservation of the species, both inside and outside the critical habitat designation, will continue to be subject to: 1
Conservation actions implemented under section 7a1 of the Act; 2
regulatory protections afforded by the requirement in section 7a2 of the Act for Federal agencies to ensure their actions are not likely to jeopardize the continued existence of any endangered or threatened species; and 3 the prohibitions found in section 9 of the Act. Federally funded or permitted projects affecting listed species outside their designated critical habitat areas may still result in jeopardy findings in some cases. These protections and conservation tools will continue to contribute to recovery of this species.
Similarly, critical habitat designations made on the basis of the best available information at the time of designation will not control the direction and substance of future recovery plans, habitat conservation plans HCPs, or other species conservation planning efforts if new information available at the time of these planning efforts calls for a different outcome.
Physical or Biological Features Essential to the Conservation of the Species In accordance with section 35Ai of the Act and regulations at 50 CFR
424.12b, in determining which areas we will designate as critical habitat from within the geographical area occupied by the species at the time of listing, we consider the physical or biological features that are essential to the conservation of the species and that may require special management considerations or protection. The regulations at 50 CFR 424.02 define physical or biological features essential to the conservation of the species as the features that occur in specific areas and that are essential to support the lifehistory needs of the species, including, but not limited to, water characteristics, soil type, geological features, sites, prey, vegetation, symbiotic species, or other features. A feature may be a single habitat characteristic or a more complex combination of habitat characteristics.
Features may include habitat characteristics that support ephemeral or dynamic habitat conditions. Features may also be expressed in terms relating to principles of conservation biology, such as patch size, distribution distances, and connectivity. For example, physical features essential to the conservation of the species might include gravel of a particular size
VerDate Sep<11>2014

15:54 Jun 30, 2021

Jkt 253001

required for spawning, alkali soil for seed germination, protective cover for migration, or susceptibility to flooding or fire that maintains necessary earlysuccessional habitat characteristics.
Biological features might include prey species, forage grasses, specific kinds or ages of trees for roosting or nesting, symbiotic fungi, or a particular level of nonnative species consistent with conservation needs of the listed species.
The features may also be combinations of habitat characteristics and may encompass the relationship between characteristics or the necessary amount of a characteristic essential to support the life history of the species.
In considering whether features are essential to the conservation of the species, we may consider an appropriate quality, quantity, and spatial and temporal arrangement of habitat characteristics in the context of the lifehistory needs, condition, and status of the species. These characteristics include, but are not limited to, space for individual and population growth and for normal behavior; food, water, air, light, minerals, or other nutritional or physiological requirements; cover or shelter; sites for breeding, reproduction, or rearing or development of offspring;
and habitats that are protected from disturbance.
Space for Individual and Population Growth and for Normal Behavior Mussels generally live embedded in the bottom of stable streams and other bodies of water, in areas where flow velocities are sufficient to remove finer sediments and provide well-oxygenated waters. The Suwannee moccasinshell inhabits creeks and rivers where it is found in substrates of sand or a mixture of sand and gravel, and in areas with slow to moderate current Williams 2015, p. 2. The species is often associated with large woody material embedded in the substrate, which may help stabilize substrates and act as a flow refuge. The Suwannee moccasinshell, similar to other freshwater mussels, is dependent on areas with flow refuges, where shear stress is relatively low and sediments remain stable during high flow events Strayer 1999, pp. 468, 472; Hastie et al.
2001, pp. 111114; Gangloff and Feminella 2007, p. 71. Substrates that remain stable in high flows conceivably allow these relatively sedentary animals to remain in the same general location throughout their entire lives. These habitat conditions not only provide space for Suwannee moccasinshell populations, but also provide cover and shelter and sites for breeding, reproduction, and growth of offspring.

PO 00000

Frm 00078

Fmt 4700

Sfmt 4700

Food, Water, Air, Light, Minerals, or Other Nutritional or Physiological Requirements Freshwater mussels, such as the Suwannee moccasinshell, siphon water into their shells and across four gills that are specialized for respiration, food collection, and brooding larvae in females. Food items include fine detritus particles of organic debris, algae, diatoms, and bacteria Strayer et al. 2004, pp. 430431, Vaughn et al.
2008, p. 410. Adult mussels obtain food items both from the water column and from the sediment, either by taking water in through the incurrent siphon or by moving material extracted from sediments into their shell using cilia hair-like structures on their foot. For the first several months, juvenile mussels feed primarily with their foot, although they also may filter interstitial pore water Yeager et al. 1994, pp.
217221. Food availability and quality for the Suwannee moccasinshell is affected by habitat stability, floodplain connectivity, flow, and water and sediment quality. Adequate food availability and quality is essential for normal behavior, growth, and viability during all life stages of this species.
The Suwannee moccasinshell is a riverine species that depends upon adequate amounts of flowing water.
Flowing water transports food items to the sedentary juvenile and adult life stages, provides oxygen for respiration, removes wastes, transports sperm to females, and maintains the stream bottom habitats where the species is found the effects of flow alteration on habitat is discussed below under Habitats Protected From Disturbance. A
sufficient amount of continuously flowing water is a feature essential to this species.
Important water quality parameters for freshwater mussels include but are not limited to dissolved oxygen DO, temperature, pH, salinity, and suspended sediment. As relatively sedentary animals, mussels must tolerate the full range of physical and chemical conditions that occur naturally within the streams where they persist, but many species are considered sensitive to disturbance. Water quality within the Suwannee River basin may vary according to season, geology, climate events, and human activities within the watershed. Dissolved oxygen DO and water temperature are important parameters for freshwater mussel early life stages, which are more sensitive to deviations from normal ranges. Water temperature also plays an important role in the overall water quality, including oxygen solubility and
E:FRFM01JYR1.SGM

01JYR1