FWS designates critical habitat for Alabama Sturgeon
74 Fed. Reg. 26488 / Vol. 74, No. 104 / Tuesday, June 2, 2009 / Rules and Regulations
DEPARTMENT OF THE INTERIOR; Fish and Wildlife Service; 50 CFR Part 17; Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for Alabama Sturgeon (Scaphirhynchus suttkusi); Final rule.
SUMMARY: We, the U.S. Fish and Wildlife Service (Service), designate critical habitat for the Alabama sturgeon (Scaphirhynchus suttkusi) under the Endangered Species Act of 1973, as amended (Act). In total, approximately 524 kilometers (326 miles) of river fall within the boundaries of the critical habitat designation. The critical habitat includes portions of the Alabama and Cahaba Rivers in Autauga, Baldwin, Bibb, Clarke, Dallas, Lowndes, Monroe, Perry, and Wilcox Counties, in Alabama.
Sturgeon is the common name used for this hard to find, large, bony-plated, primitive fish in the family Acipenseridae which typically grows slowly and matures late in life. The Alabama sturgeon (Scaphirhynchus suttkusi) is the smallest of all the North American sturgeons, typically weighing only 1 to 2 kilograms (2 to 4 pounds) at maturity. The head is broad and flattened shovellike at the snout. The species is so rare that State and Federal scientists have been using cryopreservation. Photo from DruidCityOnline and Video from Outdoor Alabama. See also U.S. Fish and Wildlife Alabama Ecological Services Field Station.
EXCERPT: Flows in the Alabama River are heavily influenced by upstream releases from Alabama Power Company and U.S. Army Corps of Engineers (USACE) hydropower projects, and riverine habitats are fragmented by Claiborne and Millers Ferry Locks and Dams. This 386-kilometer (240-mile) stretch of the Alabama River, along with the lower Cahaba River, represents the last remaining viable habitat for the sturgeon...
PRIMARY CONSTITUENT ELEMENTS (PCEs) FOR THE ALABAMA STURGEON. Under the Act and its implementing regulations, we are required to identify the physical and biological features (PCEs) laid out in the appropriate quantity and spatial arrangement within the geographical area known to be occupied by the Alabama sturgeon at the time of listing that are essential to its conservation and which may require special management considerations or protections. Based on the above needs and our current knowledge of the life history, biology, and ecology of the species, we have determined that Alabama sturgeon’s PCEs are:
1. A flow regime (i.e., the magnitude, frequency, duration, seasonality of discharge over time) necessary to maintain all life stages of the species in the riverine environment, including migration, breeding site selection, resting, larval development, and protection of cool water refuges (i.e., tributaries).
2. River channel with stable sand and gravel river bottoms, and bedrock walls, including associated mussel beds.
3. Limestone outcrops and cut limestone banks, large gravel or cobble such as that found around channel training devices, and bedrock channel walls that provide riverine spawning sites with substrates suitable for egg deposition and development.
4. Long sections of free-flowing water to allow spawning migrations and development of embryos and larvae.
5. Water temperature not exceeding 32 °C (90 °F); dissolved oxygen levels not less than 5 mg/L (5 ppm), except under extreme conditions due to natural causes or downstream of existing hydroelectric impoundments, where it can range from 5 mg/L to 4 mg/L (5 ppm to 4 ppm); and pH (a measure of acidity) within the range of 6.0 to 8.5.