Black Warrior Waterdog (Necturus Alabamensis)
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FINAL REPORT Habitat Assessment of Known Occurrences Black Warrior Waterdog (Necturus alabamensis) Sipsey Fork below AL Hwy 33 bridge (Winston County) and at Lewis Smith Dam (Walker/Cullman counties) Photos by M. Bailey Order No. 1448-43910-99-M515 March 2000 Prepared for U.S. Fish and Wildlife Service by Mark A. Bailey, Conservation Services Southeast 2040 Old Federal Road Shorter, AL 36075 (334) 727-2040 fax (334) 727-1005 Contents Introduction.................................................................................................................................1 Background ......................................................................................................................1 Historic Sites.....................................................................................................................3 Objectives ....................................................................................................................................5 Methods........................................................................................................................................5 Investigators.....................................................................................................................5 Determination of Site Condition and Status................................................................6 Site Assessments.........................................................................................................................7 Summary and Conclusion ......................................................................................................19 Threats.............................................................................................................................19 Water Quality.........................................................................................................19 Impoundments.......................................................................................................21 Introduced Species.................................................................................................21 Local Extirpation and Habitat Fragmentation...................................................21 References Cited.......................................................................................................................22 Appendix A. Quad Maps .........................................................................inside binder pockets Appendix B. Photographic Slides .................................................... vinyl slide storage pages Introduction This report summarizes activities associated with field investigations of current and historic localities for the Black Warrior waterdog (Necturus alabamensis) in Alabama. In June 1999, the U.S. Fish and Wildlife Service's Jackson, MS Endangered Species Field Office contracted with Conservation Services Southeast (CSS) to conduct this work. Background The Black Warrior waterdog is a large, gilled, aquatic salamander with a maximum recorded length of 248 mm (Bart et al., 1997). Larvae (28-48 mm total length) are dorsally dark brown or black with two light dorsolateral stripes beginning at the nostril, extending posteriorly through the eye, and terminating on the dorsal fin of the tail. Other Gulf drainage Necturus are not known to have striped larvae (Guttman et al., 1990). Subadults (40-100 mm total length) are not conspicuously marked, with little if any spotting, but a dark stripe extends from the nostril through the eye and to the gills. Adults are usually brown, may be spotted or unspotted, and retain the dark eye stripe. The largest specimen, a female from Mulberry Fork, was melanistic, with no trace of spotting or brown pigment. The ventral surface of all age classes is plain white. The striped pattern exhibited by the larvae closely resembles that of N. maculosus larvae (Hecht, 1958; Brode, 1969). The Black Warrior waterdog's presumed range (Figure 1) lies entirely within the upper Black Warrior River system. Counties of potential occurrence are Blount, Cullman, Etowah, Fayette, Jefferson, Lawrence, Marshall, Tuscaloosa, Walker and Winston. Where conditions are favorable, the Black Warrior waterdog probably inhabits larger streams (10 m wide or greater) throughout the upper Black Warrior River system. Many smaller tributaries in the region go dry in late summer due to little or no recharge from the surrounding Pottsville sandstone and shale. Originally described from the Black Warrior River at Tuscaloosa (Viosca 1937), the species has been recently reported from ten streams or major segments: the Sipsey Fork of the Black Warrior River and Brushy Creek (a tributary to the Sipsey Fork) in Winston County, Locust Fork and the Blackburn Fork of the Little Warrior River in Blount County, Mulberry Fork, Lost Creek, and Blackwater Creek in Walker County, and Yellow Creek and North River in Tuscaloosa County (Viosca, 1937, Ashton and Peavey, 1985; Bailey, 1992; Bailey, 1995; Bart et al. ,1997; Guyer, 1997). The Black Warrior waterdog may have similar hydrologic requirements to those of N. lewisi in North Carolina, which predominantly occurs in streams greater than 15 m wide and deeper than 100 cm, and is not found in streams where water flow ceases under normal summer dry weather conditions (Braswell and Ashton, 1985). 1 Figure 1. Known Occurrences of the Black Warrior Waterdog. 2 The Black Warrior waterdog can be expected to potentially inhabit the same streams as the flattened musk turtle (Sternotherus depressus), which is also restricted to permanent streams above the Fall Line in the Black Warrior River system (Mount, 1975). The historic range of these two species may have been virtually identical, and both may now be absent from large portions of formerly occupied habitat. Due largely to habitat degradation, the flattened musk turtle may currently maintain viable populations in only 142 of 947 stream miles in the upper Black Warrior system, a mere 15 percent of the formerly suitable habitat (U.S. Fish and Wildlife Service, 1990). Basic life history information is virtually nonexistent for this species. Waterdogs are rarely encountered in the summer months, and appear to be more active after water temperatures drop and leaf beds begin to accumulate in late fall. Neill (1963), commenting on seasonal activity patterns of other Necturus species, noted that waterdogs are most often active on cold stormy nights or after heavy rains have swollen streams to near flooding, conditions under which predatory fishes are least likely to be actively foraging. Black Warrior waterdog larvae and adults have been collected from submerged leaf beds and adults have been electroshocked from beneath submerged ledges and flat rocks. Leaf beds are often rich in invertebrate life, and are probably used as both shelter and foraging habitat. Age at sexual maturity is unknown. Post-hatchling larvae have been collected in November and December, suggesting late spring or early summer nesting (Ashton and Peavy, 1986). Historic Sites According to a summary of five sources (Ashton, in litt.; Ashton and Peavey, 1985; Bailey, 1992; Bailey, 1995; and Guyer, 1997) provided by the U.S. Fish and Wildlife Service on June 13, 1999, and two additional sources (Viosca, 1937; Bart et al., 1997), Necturus alabamensis has been collected from the following sites: BLOUNT COUNTY -- 2 (3?) sites 1. Locust Fork (several unspecified localities, dates probably 1984-85). 2. Blackburn Fork (=Blackburn "Branch") / Little Warrior River. At least two localities, some of which could not be relocated with certainty. • "North of Locust Fork." Two specimens, 1 January 1985; one specimen, 23 February 1985; four specimens, 16 March 1985. (Ambiguous locality data; could be any of 3 or 4 sites.) • Blackburn Fork at Co. Rd. 15 (T13S R1W Sec 13). Adults and larvae collected by Ashton (1989? See also 1984 and 1985 Ashton records below which are probably referable to this site). Not found by Bailey in 1991 and 1995, specimen(s) collected by Guyer in 1997. A. Little Warrior River 0.5 mi WSW of AL Hwy 79 Bridge. One specimen, 28 March 1985. R. Ashton. (Note: the Little Warrior is not to be found WSW of the bridge, and this is may be a transcription error. If "WSW" is replaced with "ESE," then it is the Co. Rd. 15 site.) B. Blackburn Branch [sic] 1 mi ESE AL Hwy 79. Six specimens, 9 December 1984. R. Ashton. (Note: this and the previous record are likely synonymous with the Co. Rd. 15 site). 3 TUSCALOOSA COUNTY -- 3 sites 1. Black Warrior River "near Tuscaloosa." 22 January 1914. Collector unknown, reported by Viosca (1937). Holotype, USNM 102676. Viosca reports a second specimen from the same locality. 2. Yellow Creek, T20S R9W Sec. 2. 12 December 1991. M. Bailey. One striped subadult collected from a large leaf bed after about 30 minutes of sampling effort. 3. North River at Co. Rd. 83 (above Lake Tuscaloosa). 11 December 1991. M. Bailey. Two Necturus larvae, one striped (N. alabamensis form) and one unstriped (N. c.f beyeri form) collected from a small leaf bed after 30 minutes sampling effort. WALKER COUNTY -- 4 sites 1. Lost Creek at Confluence with Guthrie Creek. 11 December 1991. M. Bailey. One adult collected from leaf beds at mouth of Guthrie Creek. 2. Mouth of Blackwater Creek at Mulberry Fork/Mouth of Little Blackwater Creek at Blackwater Creek (sites are ca. 1000 ft apart and herein considered as one). 1997. Specimen(s) reported by Guyer from mouth of Little Blackwater Creek. Bailey (1995) reports anecdotal evidence