OT United States Department of the Interior

FISH AND WILDLIFE SERVICE 446 Neal Street Cookeville, TN 38501

November 14, 2013

Lt. John L. Hudson District Engineer U.S. Army Corps of Engineers, Regulatory Branch 3701 Bell Road Nashville, Tennessee 37214

Attention: Bradley N. Bishop, Chief, Western Regulatory Section, Operations Division

Re: FWS 42013-F-0540. File No. LRN-2011-01152; Section 7 Consultation for Proposed Maintenance (Wingwall Replacements at Two Road Crossings) within Two Unnamed Tributaries near Mile 9.3R. Mill Creek, Opposite Cumberland River Mile 1 94.4L, Davidson County, Tennessee

Dear Colonel Hudson:

This document is the biological opinion of the U.S. Fish and Wildlife Service (Service) based on our review of Nashville Metro Water Services, Stormwater Division's (Metro) Proposed Wingwall Replacements at Two Crossings within Two Unnamed Tributaries to Mill Creek, near Mile 9.3R, Opposite Cumberland River Mile 1 94.4L in Davidson County, Tennessee, and its effects to the endangered Nashville ( shoupi) per section 7 of the Endangered Species Act (Act) of 1973, as amended (16 U.S.C. 1531 et seq.). Your June 12, 2013, request for formal consultation was received on June 18, 2013.

This biological opinion is based on information provided in two biological assessments, both dated November 30, 2012, a U.S. Army Corps of Engineers' (Corps) Clean Water Act (CWA), Section 404, Removal-Fill Permit Application, and construction plans. A complete administrative record of this consultation is on file and available for review at the Tennessee Ecological Services Field Office, 446 Neal Street, Cookeville, Tennessee 38501.

Consultation History

March 15, 2013 The Corps received a letter, dated March 8, 2013, from AMEC Environment and Infrastructure, Inc. (AMEC), a CWA, Section 404, Removal-Fill Permit Application, and two biological assessments for the proposed action. AMEC indicated that eight wingwalls had separated from two culverts at two sites within two unnamed Mill Creek tributaries as a result of the May 2010 flood, and the requested permit was needed to replace all eight wingwalls. The project proponent was Metro (letter from Richard L. Williams [AMEC] to Scott Fanning [Corps]).

May 13, 2013 The Corps sent an e-mail to the Service's Tennessee Field Office (TFO) asking it to review and provide comments on a Site Review for Summer Bat Habitat conducted at the proposed project sites and completed by AMEC. AMEC had concluded that the proposed project is unlikely to adversely affect the Indiana bat (Myotis sodalis) or its summer roosting habitat (e-mail from Richard Graham [Corps] to David Peiren [Service]).

May 31, 2013 The Service responded to the Corps' May 13, 2013, e-mail request via phone and indicated that the proposed action is not likely to adversely affect the Indiana bat (telephone call from Dave Pelren to Richard Graham).

June 18, 2013 The Corps' June 12, 2013, letter, requesting initiation of formal consultation, the two biological assessments and the Section 404, Removal-Fill Permit Application arrived at the TFO. In the letter, the Corps indicated that it had determined that the proposed work is likely to adversely affect the Nashville crayfish and that the federally endangered Indiana bat would not be adversely affected by the proposed project (letter from Timothy Higgs [Corps] to Mary Jennings [Service]).

July 17, 2013 The TFO responded to the Corps' June 12, 2013, request for formal consultation, indicating that initiation of formal consultation under section 7 of the Act was complete (letter addressed to Colonel Hudson [Corps] and signed by Mary Jennings).

October 17, 2013 The TFO sent an e-mail to the Corps indicating that the competition date for the consultation (finalization of this biological opinion) had been extended to November 17, 2013, to account for the 16-day period of the October 2013, federal government shutdown and associated furlough of Service employees. The Corps responded that it was agreeable to the new completion date (e-mail exchange between Todd Shaw [Service] and Casey Ehorn [Corps]). FWSLog No: 2013-F-0540 Application No: LRN-201 1-01152 Date Started: October 31, 2013 Ecosystem: Lower Tennessee-Cumberland Applicant: Nashville Metro Water Services, Stormwater Division's Action Agency: U.S. Army Corps of Engineers Project Title: Proposed Wingwall Replacements at Two Crossings within Two Unnamed Tributaries to Mill Creek, near Mile 9.3R, Opposite Cumberland River Mile 194.41, County: Davidson

Table 1. Species and critical habitat evaluated for effects and those where "no effect" was determined or the Service has concurred with a "not likely to adversely affect" determination. PRESENT IN ACTION AREA BUT SPECIES or CRITICAL PRESENT IN "NO EFFECT" OR "NOT LIKELY HABITAT ACTION AREA TO BE ADVERSELY AFFECTED" Nashville crayfish (Orconectes sho up!) X Indiana bat

(Myotis soda/is) - X

BIOLOGICAL OPINION

DESCRIPTION OF THE PROPOSED ACTION

The proposed action would replace wingwalls at two concrete box culvert crossings in two unnamed tributaries to Mill Creek on State Asylum Road (McGavock Pike) in Davidson County, Tennessee. The unnamed tributaries cross underneath McGavock Pike and empty directly into Mill Creek. The two sites will hereafter be referred to as Site Location North (SLN) and Site Location South (SLS) to distinguish each individual site in this biological opinion. SLN be located at an approximate latitude of 36.094647 decimal degrees [DD] and an approximate longitude of -86.689911 DD; SLS would be located at an approximate latitude of 36.093 778 DD and an approximate longitude of -86.688361 DD (AMEC Environment and Infrastructure, Inc., 2012a; AMEC Environment and Infrastructure, Inc., 2012b; U.S; Army Corps of Engineers 2013a) (see Figure 1).

Both tributaries originate along the southern edge of the Nashville Metropolitan Airport at an approximate elevation of 530 feet (ft) (AMEC Environment and Infrastructure, Inc. 2012a; AMEC Environment and Infrastructure, Inc. 2012b). The tributary containing SLN flows southwest for approximately 0.7-mile (mi) to its confluence with Mill Creek; the tributary containing SLS flows southwest for approximately 0.9-mi to its confluence with Mill Creek (Antioch, Tennessee, 7.5-minute U.S. Geological Survey Topographic Quadrangle Map). The existing culvert at SLN is situated on the unnamed stream approximately 112 ft upstream of its 3 Figure 1. Wingwall replacement sites at two road crossings within two unnamed tributaries near mile 93.R. Mill Crk confluence with Mill Creek and has an estimated length of 30 ft (actual length not provided by project proponent), width of 9 ft and height of 11 ft; the existing culvert at SLS is situated on the other unnamed stream approximately 44 ft upstream of its confluence with Mill Creek and has an estimated length of 30 ft (actual length not provided by project proponent), width of 8 ft and height of 11 ft. A total of eight wingwalls would be replaced; two downstream of each culvert and two upstream of each culvert. The proposed wingwalls would be 12 inches (in) thick and 14 ft long and 7 ft high (U.S. Army Corps of Engineers 2013a).

The proposed construction activities would be completed in conjunction with approved Best Management Practices (BMP5) to protect the stream channels. The existing wingwalls would be removed with as minimal disturbance as possible. Areas surrounding the forms would be dug by hand. No instream construction is proposed. Specific notes would be included on project plans to provide attention to erosion and sediment control measures. The stream channels would also be protected by 30-ft buffers on each side, as required by Metro Division of Water Pollution Control. In addition to sediment and erosion control measures, biologists would collect all crayfish in the vicinities of the box culverts just prior to construction activities. A biologist familiar with the Nashville crayfish, and holding valid state and federal permits, would coordinate the proposed relocation activities. All crayfish would be documented and transported a minimum of 50 meters (m) (approximately 165 ft) upstream of proposed construction activities. All activities would be coordinated and approved by the Service (AMEC Environment and Infrastructure, Inc. 2012a; AMEC Environment and Infrastructure, Inc. 2012b).

Because the project proponent has indicated that "no instream construction is proposed", the Service has assumed in this biological opinion that no equipment would be operated instream. However, some instream disturbances, not involving instream equipment (at sites where existing wingwalls would be removed and new wingwalls placed), would still occur. Based on this assumption, the Service has further assumed that the existing wingwalls would be removed with a crane or similar type of equipment, located above the ordinary high water line (OHW), and no coffer dams would be constructed in the active stream channels. The project proponent also failed to mention whether the new wingwalls would be pre-constructed (pre-cast) and installed with a crane or similar type of equipment or if they would be constructed on-site (cement poured into forms). Therefore, the Service has attempted to address the effects of installing the proposed wingwalls as either/or (placed/constructed) in this biological opinion.

The project footprint would include areas directly impacted by the action in the immediate vicinities of the two box culverts and comprised of space currently occupied by the existing wingwalls and where the replacement wingwalls would be installed, crayfish relocation sites and equipment staging areas. Approximately 7,456 square feet (ft) of aquatic area within the footprint would be located below OHW on the two unnamed tributaries to Mill Creek. The reminder of the footprint would be comprised of approximately 16,490 ft2 of terrestrial area located within the project area above the OHW, including the equipment staging areas in the adjacent floodplain (the Service has assumed the staging areas would occupy a total of 10,890 ft2 or 0.25-acre [ac]; the project proponent failed to provide this information).

5 The action area for the proposed project would include all areas on land and in water directly and indirectly impacted by pre-project construction, project construction and post-project operations.

The Service has estimated the project action area to include a total of approximately 184,986 ft2 (4.3 ac), containing the following aquatic and terrestrial areas: (1) beginning approximately 165 ft upstream of McGavock Pike on the unnamed tributary including SLN (where captured crayfish would be released), and extending downstream approximately 339 ft (0.06-mi) to the stream's confluence with Mill Creek, (2) beginning approximately 165 ft upstream of McGavock Pike on the unnamed tributary including SLS (where captured crayfish would be released), and extending downstream approximately 271 ft (0.05-mi) to the stream's confluence with Mill Creek, and (3) approximately 1,848 ft (0.35-mi) of the Mill Creek stream channel downstream from Mill Creek's confluence with the unnamed tributary encompassing SLS. The action area would include the stream channels and streambanks of the two unnamed Mill Creek tributaries, the stream channel of Mill Creek, and equipment staging areas located within the adjacent floodplain. This 4.3-ac area has been identified as the action area for reasons that will be explained and discussed in the "EFFECTS OF THE ACTION" section of this consultation.

STATUS OF THE SPECIES/CRITICAL HABITAT

Species/critical habitat description

The Nashville crayfish (Orconectes shoupi) was listed as an endangered species on September 26, 1986 (51 FR 34410 34412). Because the entire known range of the species is contained within the boundaries of Metropolitan Nashville, where significant residential and commercial development had occurred prior to its listing and was anticipated to continue into the foreseeable future, it was determined that designation of critical habitat would substantially increase the potential for take of the species; therefore, critical habitat was not designated for the Nashville crayfish (U.S. Fish and Wildlife Service 1989). The Nashville crayfish is endemic to the Mill Creek drainage in Davidson County and Williamson County, Tennessee. The species is currently known to occur in Mill Creek and Mill Creek tributaries, including Collins Creek, Owl Creek, Edmonson Branch, Sims Branch, Sevenmile Creek, Sorghum Branch, Whittemore Branch, Turkey Creek, Indian Creek, Holt Creek, four unnamed tributaries to Mill Creek, one unnamed tributary to Owl Creek and one unnamed tributary to Sims Branch.

There are historic collection records of Nashville crayfish in streams outside of the Mill Creek drainage. Records from the South Harpeth River in Davidson County, Tennessee, and Big Creek (Elk River tributary) in Giles County, Tennessee, however, are thought to be based on "bait bucket" introductions of the species, and Nashville crayfish records from Richland Creek (O'Bara et al. 1985; Bouchard 1976; Bouchard 1984) in Davidson County (Cumberland River system), Tennessee, were later discovered to be misidentifications (Bouchard, personal communication, 1988). Originally thought to solely be a stream-dwelling species, Nashville crayfish have also recently been collected from impoundments, overflow pools adjacent to Mill Creek and small, intermittent tributaries in the Mill Creek watershed; those specific locations have been included in the life history discussion below. 6 The Nashville crayfish is a large species, growing to length of up to 7 inches (in). Body coloration is variable, ranging from green to dark brown. Many, individuals have an area of lighter coloration on the dorsal shell that forms a "saddle" on the back. The shell ends anteriorly in a sharp point between the eyes. It has thickened ridges on its rostrum, four pair of pereopods (walking legs), and two elongated chelae (claws) with distinct orange and black tips (U.S. Fish and Wildlife Service 1989; O'Bara et al. 1985). Size of carapace lengths ranges from 0.3 to 4.7 centimeters (cm) (0.12 to 1.9 in) (Carpenter 2002).

Life history

Little is known about the life history of the Nashville crayfish. It is assumed that their life history traits are similar to other crayfish species. Most common stream-dwelling species of crayfish (non-burrowing and non-cave-dwelling species) live an average of four to five years (Bergey et al. 2005). Raccoons, fish and reptiles are typically the main predators of crayfish. Crayfish are omnivorous, feeding on a variety of plant and material, including algae, insects, worms, fish eggs, snails and mussels.

Individual Nashville crayfish have been found in a variety of habitat types, including gravel/cobble runs, pools with as much as 10 cm (3.9 in) of accumulated sediment, and in areas with intermittent flow (U.S. Fish and Wildlife Service 1987). Adults tend to be solitary, seeking cover under large rocks, logs, debris or rubble; the largest individuals generally select the largest cover available (U.S. Fish and Wildlife Service 1987).

Nashville crayfish recently collected from impoundments, overflow pools adjacent to Mill Creek and small, intermittent tributaries in the Mill Creek watershed include: (1) 809 Nashville crayfish found in a small impoundment on a tributary to Mill Creek; (2) a live Nashville crayfish collected from a rock outcropping along the shoreline of a 5-ac impoundment on a Mill Creek tributary that was drained for a residential development (U.S. Fish and Wildlife Service 2011); (3) four Nashville crayfish collected from a retention pond adjacent to Owl Creek (Cook and Walton 2008); and (4) an unspecified number of Nashville crayfish collected from a pond adjacent to Sims Branch (Withers, personal communication, 2009).

Cook and Walton (2008) attempted to more explicitly describe habitats used by the species, but because of a severe drought during their 2007 study, their models may only reflect habitats used during stress periods. Their study indicated the most important microhabitat variables for Nashville crayfish at least during a drought year, appear to be cover rock surface area (size of rocks used for cover) and depth. Reproductive females are typically found under large slab rocks and in isolated areas near banks during spring, in preparation for brood hatching. Cover rocks of at least 0.02-square meter (m 2 ) ( 2.15 ft2) may be important habitats for females releasing broods and for protection during molting after releasing broods (U.S. Fish and Wildlife Service 1987). Nashville crayfish were found at least 50 percent (%) of the time in runs, using cover rocks with a surface area of 0.05-rn 2 (0.54-ft2), and at least 50% of the time in pools, when cover rock area increased to 0.10-rn2 (1.1 ft2) Larger rock areas may be needed in pools to decrease risk of predation, whereas smaller rock areas would provide adequate protection in runs (Cook and

7 Walton 2008). Instream cover is also important for Nashville crayfish during the time when they are molting. Cover is aggressively defended; larger individuals drive smaller crayfish from their selected cover.

Crayfish typically molt six or seven times during their first year of life and once or twice a year for the remainder of their lives. Males molt back and forth between a reproductive form (Form I) and a non-reproductive form (Form II) (Georgia College 2012). Reproduction begins when males change from Form II to Form I. The primary differences between Form I and Form II males are development of the chelae and the shape of the reproductive organ which is known as the first swimmeret (pleopod; i.e., swimming legs), or gonopod (Georgia College 2012). During Form I, the male's chelae become elongated and enlarged, hooks appear at the base of the third and fourth sets of pereopods, and the first two pairs of swimmerets become hardened. The hook and the larger chelae are used for grasping females during mating. The female's annulus ventrilis (seminal receptacle on sternum) hardens and becomes grooved during Form I. In juvenile and Form II males, the gonopod appears to be the same color and consistency throughout its length and has more blunt and rounded features (Georgia College 2012). According to Barrociere (1986), Nashville crayfish reach sexual maturity during early spring of the year following their hatching; Withers (personal communication, 2012a) has further indicated that Nashville crayfish hatched early in the year likely reach sexual maturity within their first year of life, while those hatched later in the year would be expected to reach sexual maturity during their second year of life.

The Nashville crayfish reproductive period, which includes mating, spawning, egg release, egg incubation and hatching, occurs from approximately October 1 to May 31 (Barrociere 1986). Mating in Nashville crayfish is assumed to be similar to that of other crayfish species, consisting of short exchanges of tactile and olfactory signals, after which males grasp females by their chelae, turn them on their backs, and release spermatophores, which attach to the thoracic sternites (ventral surface of body segments) of the females; fertilization is therefore external, and spawning occurs a few days or weeks after mating (Acquistapace et al. 2002). The female guards eggs developing under her abdomen, a period during which females typically do not eat (Galeotti et al. 2006). Withers (personal communication, 2012b) estimated the average clutch size for the Nashville crayfish at approximately 100 eggs per female. Nashville crayfish egg- laying occurs during late winter and early spring. Smart (1962) found that the female Cambarus longulus longulus, a crayfish species closely related to the Nashville crayfish, carried eggs approximately 35 days from late April through late May. Barrociere (1986) noted that the period of egg-laying and embryonic development of Nashville crayfish in Mill Creek occurred from late March through mid-May (Barrociere 1986).

When female crayfish are ready to lay eggs, they usually find a secure hiding place and, hence, are rarely encountered. Like other crayfish species, when the female Nashville crayfish releases her eggs, she attaches them to her swimmerets and is said to be "in berry" (Georgia College 2012). Upon hatching, the juvenile crayfish are attached to the mother by the "telson thread". Embryos develop in approximately three weeks and the hatchlings remain attached to the swimmerets of the mother for approximately another two weeks (Barrociere 1986). Throughout this period, besides providing protection, females continuously fan and groom the eggs and

F:;] hatchlings (Reynolds 2002). After the juveniles molt for the second time, they are free of the mother, but stay close and cling to the mother's abdomen for several weeks through late spring until they move off on their own (Georgia College 2012).

Population dynamics

Although survey data are accumulating to allow better understanding of the current status and size of the Nashville crayfish population, there is no comprehensive or conclusive data set available at this time. However, previous surveys and studies indicate that the species persists throughout the Mill Creek drainage. Population estimates for Nashville crayfish, based on surveys conducted from July 1999 through August 2001, ranged from 1,854 to 3,217 individuals per 100 in (328 ft) at sites in mainstem Mill Creek and from 404 to 1,425 individuals per 100 in at a site in Sevenmile Creek. Overall, it was determined that population densities may have been as high as 1,000 to 2,000 individuals perlOO in in the drainage (Carpenter 2002). Results of surveys conducted between 1988 and 2003 indicate that the Nashville crayfish occurs primarily in the middle-to-upper reaches of the Mill Creek system. During that period, approximately 60 individuals were collected within the lower 5 mi of Mill Creek, while more than 5,400 individuals were collected at 16 sites between Mill Creek Mile (MCM) 7.5 and 20.5 (U.S. Fish and Wildlife Service 2011).

Juvenile crayfish (with lengths under 20 millimeters [0.79-in]) comprised 45% of all Nashville crayfish collected during August and September 1998, and September of 1999, at 12 sampling locations throughout the Mill Creek watershed (O'Bara 1999). Summer (August-September) sex ratios for Nashville crayfish in the Mill Creek system varied from 0.85:1.17 male:female (46% and 54%, respectively) to approaching 1:1 male:female (50% and 50%, respectively) (O'Bara 1999; O'Bara and Mason 1990). Carpenter (2002) determined that 1,716 Nashville crayfish captured from the Mill Creek watershed over a three-year period had an overall male:female sex ratio of 0:82:1.2 (55% and 45%, respectively) comprised of 858 males, 704 females and 154 of unknown sex.

Status and distribution

Because its range is restricted to the Mill Creek drainage, and because significant destruction and modification have occurred to habitat throughout its range, the Nashville crayfish was listed as an endangered species. Habitat destruction and modification in Mill Creek and its tributaries are primarily the result of rapid urban development and consequent water quality degradation in Metropolitan Nashville. Water quality and aquatic faunal diversity have been significantly impacted by development in the lower reaches of the drainage and historically by agricultural activities in the upper portion of the drainage (51 FR 34410 - 34412).

The middle and lower reaches of the Mill Creek drainage are located within the highly urbanized area of Metropolitan Nashville. Stormwater runoff from streets and parking lots and discharges from commercial and municipal facilities have likely affected the stream and aquatic fauna. Water quality sampling has revealed measurable levels of various heavy metals, poly-aromatic hydrocarbons and other pollutants that could have adverse impacts on aquatic organisms. In 1989, a spill of aviation fuel occurred at the Nashville International Airport. Despite state-of- the-art measures that were in place to control such incidents (i.e., oil/water separators), the fuel entered Sims Branch, a tributary to Mill Creek. Booms were placed near the mouth of Mill Creek to prevent the fuel from entering the Cumberland River, but an inspection of Sims Branch by biologists from the TWRA and the Service revealed that the spill had affected aquatic life in the stream; dead fish and crayfish were found throughout Sims Branch (U.S. Fish and Wildlife Service 2011).

Installation of fiber optic cables in Nashville in 2000 resulted in various incidents of frac-out (i.e., fracturing of bedrock) during horizontal directional drilling operations, which resulted in large amounts of bentonite slurry, and possibly, other pollutants, entering numerous streams in the Mill Creek watershed (U.S. Fish and Wildlife Service 2011).

Other incidents, involving construction of road crossings, associated with various development activities in the Mill Creek drainage, have resulted in frac-out and de-watered portions of streams. These impacts have killed aquatic species, including crayfish.

In April 2010, the TFO received a report of aircraft de-icer spilling into Sims Branch which originates on the Nashville International Airport property. Dead fish and crayfish were observed in the stream and in a pond constructed downstream from the airport.

Other potential threats to the species include the introduction of other crayfish species into Nashville crayfish habitat, which could be bait released by fishermen or unwanted pets released by pet owners, resulting in added competition for food and shelter and potential genetics concerns (i.e., crossbreeding). These threats have been observed world-wide with other species of crayfish on an increasing basis (Bergey et al. 2005).

A recovery plan was approved for the Nashville crayfish on August 12, 1987, and a revised plan was approved on February 8, 1989. Because its entire known range is located within a major metropolitan area, which is subject to activities that adversely affect the species and its habitat, removal of the Nashville crayfish from the legal protection of the Act is unlikely. However, the species may be reclassified to threatened status if the following criteria are met:

Through protection of the existing Mill Creek basin population and by reintroduction of the species into Richland Creek (Cumberland River tributary) or by discovery of an additional distinct population, there exist two viable populations.

2. A Richland Creek population or a discovered population must: (a) have been established or be self-sustaining for a minimum of ten years without augmentation from an outside source, (b) represent a significant component of the crayfish fauna throughout most of the creek, and (c) be stable or increasing in numbers and range.

10 3. The species and its habitat in the Mill Creek. system and one other system are protected from human-related and natural threats that would be likely to cause the species' extinction in the foreseeable future.

Although the species and its aquatic habitat continue to be impacted, the Nashville crayfish persists in the Mill Creek drainage. Nashville crayfish have been collected throughout the mainstem of Mill Creek, in Sims Branch, Sevenmile Creek, Whittemore Branch, Collins Creek, Turkey Creek, Indian Creek, Owl Creek, Edmonson Branch, Sorghum Branch, Holt Creek, four unnamed tributaries to Mill Creek, one unnamed tributary to Owl Creek and one unnamed tributary to Sims Branch. A particular site may support a few to hundreds of Nashville crayfish. Originally thought to be a stream-dwelling species, Nashville crayfish have recently also been found in impoundments, overflow pools adjacent to Mill Creek and small, intermittent tributaries in the Mill Creek watershed (Cook and Walton 2008; Withers 2009, personal communication).

Nashville crayfish records from streams outside the Mill Creek system are believed to be based on "bait bucket" introductions or misidentifications. None of these populations are presently extant. Therefore, considering this information, in addition to the latest evidence concerning the distribution of the species, the criteria contained in the species' recovery plan for reclassification of the Nashville crayfish to threatened status are not achievable.

Analysis of the species/critical habitat likely to be affected

The Nashville crayfish is the only species that will be addressed in this biological opinion. The federally listed Indiana bat may also occur in the vicinity of the proposed action. However, the Corps previously coordinated with the Service, and it was determined that the proposed project is not likely to adversely affect the Indiana bat (U.S. Army Corps of Engineers 2013b; refer to May 13 and May 31, 2013, events in the Consultation History). Other than the Nashville crayfish and Indiana bat, available endangered species records do not indicate that any other federally endangered or threatened species is likely to occur in the action area. No federally designated critical habitat exists for the Nashville crayfish or Indiana bat within the action area or in the nearby vicinity.

Nashville crayfish are likely to be affected by the proposed action because they have been found within and near the action area. The species has been found within the action area in the immediate vicinity of the box culvert at SLN, and near the action area at sites in Mill Creek, approximately 0.2-mi upstream of the Mill Creek confluence with the unnamed tributary containing SLS and approximately 0.6-mi downstream of the Mill Creek confluence with the unnamed tributary containing SLN (O'Bara 1999; Tennessee Department of Environment and Conservation 2013; Withers, personal communication, 2013). An effects analysis is presented in the next section.

No critical habitat is currently designated for the Nashville crayfish. Therefore, the proposed action would not adversely modify or destroy any designated critical habitat for the federally listed Nashville crayfish.

11 ENVIRONMENTAL BASELINE

Both of the unnamed tributaries to Mill Creek lie entirely within Davidson County. The tributary containing SLN flows southwest for approximately 0.7-mi and the tributary containing SLS flows southwest for approximately 0.9-mi before both empty into Mill Creek from the right descending streambank (north bank) in the approximate vicinity of MCM 9.3. Their Mill Creek confluences are separated by approximately 435 ft (approximately 0.8-mi) of the Mill Creek stream channel. The tributaries are confined by a network of streets and major highways. The Nashville Metropolitan Airport, Middle Tennessee Mental Health Institute and other major urban developments are located in near proximity to the two streams. Despite these developments, both tributaries appear to have fairly intact and heavily-vegetated riparian corridors (Antioch, Tennessee, 7.5-minute U.S. Geological Survey Topographic Quadrangle Map).

Mill Creek originates in Williamson County, Tennessee, and flows in a northerly direction for 29.8 mi (Cook and Walton 2008). It crosses into Davidson County at approximately MCM 7.5 and continues to flow north for approximately 15.5 mi before joining the Cumberland River at Cumberland River Mile 194.5. The drainage area is 108 square miles (mi 2) and is located within the Central Basin Physiographic Region, an area approximately 6,000 to 7,200 mi 2 in size, which is comprised predominately of Ordovician limestones and shales. Five major tributaries contribute to the system, including Owl Creek, Indian Creek, Turkey Creek, Sorghum Branch and Sevenmile Creek. Instream habitat consists of bedrock, gravel, small cobble, sand, and silt (Cook and Walton 2008).

The headwaters of Mill Creek flow primarily through rural, sparsely populated, agricultural lands. The lower reach, however, is located within the heavily developed metropolitan area of Nashville. As the city has grown, development has spread toward the headwaters of the drainage and agricultural lands have been increasingly converted to residential and commercial developments. Substrate in the stream throughout the drainage consists of coarse gravel and bedrock in various combinations.

The upper reach of Mill Creek and its tributaries have been impacted by runoff from the agricultural lands through which they flow. The lower portion of the drainage has been heavily impacted by urban development. Commercial, residential and industrial developments have affected the stream and encroached on the floodplain. Potable water, gravity sewer, natural gas, electric/cable television (CATV) and telephone utility lines have been constructed along and across Mill Creek and its tributaries to provide those utilities to homes, businesses and industrial facilities.

Development activities in the Mill Creek drainage have had significant impacts on the streams and affected their aquatic communities. New construction often results in the removal of riparian vegetation and disturbance to streambeds. The headwater reach of Sims Branch, a Mill Creek tributary, was filled during construction activities at the Nashville International Airport. A significant spill Of aircraft fuel into Sims Branch also occurred after completion of the new airport terminal.

12 By 1984, approximately 40% of the Mill Creek watershed had been developed (U.S. Army Corps of Engineers 1984). Although the upper reach of the Mill Creek drainage had not been developed at that time, agricultural activities in the upper drainage were degrading aquatic habitat and water quality (due to organic enrichment), and habitat condition was considered to be poor (U.S. Army Corps of Engineers 1981). However, development continues to expand within the drainage, including within the upper reaches of Mill Creek and its tributaries, which are undergoing increasing amounts of residential development. These activities are likely resulting in continued degradation of water quality. Kills of crayfish have also been reported periodically, likely the result of fertilizer and pesticide runoff from residential lots.

Currently, 21 stream reaches in Mill Creek and its tributaries are listed as impaired on the State of Tennessee's 303(d) list (Tennessee Department of Environment and Conservation 2012). Impairment of stream reaches in the drainage is the result of low dissolved oxygen, siltation, removal of riparian vegetation, nutrient enrichment, and high bacteria levels from stormwater discharges, sewage collection system failures, land development and unrestricted cattle access (Tennessee Department of Environment and Conservation 2012).

Status of the species within the action area

The Service has described the project action area as occurring in Davidson County, Tennessee, and being approximately 4.3 ac in total size, containing the following aquatic and terrestrial areas: (1) beginning approximately 165 ft upstream of McGavock Pike on the unnamed tributary including SLN (where captured crayfish would be released), and extending downstream approximately 339 ft (0.06-mi) to the stream's confluence with Mill Creek, (2) beginning approximately 165 ft upstream of McGavock Pike on the unnamed tributary including SLS (where captured crayfish would be released), and extending downstream approximately 271 ft (0.05-mi) to the stream's confluence with Mill Creek, and (3) approximately 1,848 ft (0.35-mi) of Mill Creek downstream from Mill Creek's confluence with the unnamed tributary encompassing SLS. The action area would include the stream channels and streambanks of the two unnamed Mill Creek tributaries, the Mill Creek stream channel, and equipment staging areas located Within the adjacent floodplain. These stream reaches were determined to be part of the action area because the Nashville crayfish has recently been collected and observed in the reach encompassing SLN (Tennessee Department of Environment and Conservation 2013; Withers, personal communication, 2013), the species is assumed to be present in the other reaches based on known occurrences in adjoining Mill Creek reaches (O'Bara 1999; Tennessee Department of Environment and Conservation 2013), and the effects of work activities associated with the proposed action could potentially extend downstream to the distances described above and affect any individuals present.

Withers and McCoy found one adult male (Form II) and one adult female (both approximately 4.5-in total length) and one juvenile male (approximately 2-in) in Mill Creek at the confluence with the unnamed tributary containing SLN on July 8, 2005; they also found one juvenile female (approximately 2-in) in the unnamed tributary downstream of the box culvert (Tennessee Department of Environment and Conservation 2013; Withers, personal communication, 2013). Houghton, Boyd and Withers observed one adult female, one adult male (Form I), one adult male

13 (Form II) and several juveniles and young-of-year (YOY) Nashville crayfish approximately 0.2- mi upstream of the Mill Creek confluence with the unnamed tributary containing SLS on August 18, 2009 (Tennessee Department of Environment and Conservation 2013); O'Bara (1999) also observed Nashville crayfish (number unknown) at this site on September 2, 1998. Withers observed adult, juvenile and YOY Nashville crayfish (number unknown) in Mill Creek approximately 0.6-mi downstream of the Mill Creek confluence with the unnamed tributary containing SLN on June 19, 2008; ); O'Bara (1999) also observed Nashville crayfish (number unknown) at this site on March 23, 1999. Therefore, based on past occurrence records of the species within or in the near vicinity of the action area, we believe the species currently occurs throughout the action area.

Factors affecting species environment within the action area

Within the action area, the Nashville crayfish is being affected by urban developments. The Nashville Metropolitan Airport, Middle Tennessee Mental Health Institute, various industrial complexes, commercial businesses, parking lots, streets, highways and public utilities (potable water, gravity sewer, natural gas, electric/CATV and telephone) have been constructed near or across the unnamed tributaries and Mill Creek. Sediment from these developments is likely affecting the habitat of Nashville crayfish. Development activities resulting in soil erosion and contributing sediment into streams can lead to loss of riparian plant communities, streambank collapse, excessive instream sediment deposition, and increased water turbidity and stream temperatures. Sediment has been shown to abrade and/or suffocate bottom-dwelling algae and clog gills of benthic macroinvertebrates (Waters 1995).

Due to the presence of an established network of roads within the vicinity of the action area, the potential exists for an accidental toxic chemical spill. Sources of such spills include potential accidents involving vehicles transporting chemicals over road crossings of streams inhabited by the Nashville crayfish and runoff of contaminants (de-icing chemicals, oil, etc.) from roads. One of the runways at the Nashville Metropolitan Airport drains to the unnamed tributary containing SLN. Spills of aviation fuels and aircraft de-icer have occurred at the airport in the past and accidentally entered Mill Creek via Sims Branch, another Mill Creek tributary (U.S. Fish and Wildlife Service 2011). Therefore, the potential does exist for such occurrences.

EFFECTS OF THE ACTION

Factors to be considered

The proposed action would occur within two unnamed tributaries to Mill Creek and mainstem Mill Creek. The Nashville crayfish is known to occur in one of the tributaries (containing SLN) and throughout Mill Creek and is assumed to occur in the other tributary (containing SLS) based on nearby occurrence records of the species (O'Bara 1999; Tennessee Department of Environment and Conservation 2013; Withers, personal communication, 2013). Activities associated with the proposed action would have the potential to accelerate erosion and increase sedimentation into these streams, resulting in adverse impacts to the aquatic environment.

14 Removal and fill activities, and removal of existing vegetation can disrupt natural drainage patterns and expose soil on streambanks and in floodplains, often resulting in increased erosion and runoff into the stream. Excessive sedimentation can alter stream channel morphology and contribute to increased flooding. It can also result in increased water temperatures and oxygen demands, which can injure or kill aquatic organisms. Deposition of sediment on the channel bottom also degrades aquatic habitat by embedding substrate and smothering bottom-dwelling organisms. In addition, fines often transported to proposed work sites with gravel and riprap can be inadvertently introduced into streams, further contributing to embedding substrate and smothering organisms.

Turbidity, induced by accelerated erosion and sedimentation, may result in further damage to aquatic systems. Increased particulate matter suspended in the water column (suspended solids) may drive mobile, aquatic organisms from the affected area by irritating gills, concealing forage and destroying vegetation that may be essential for reproductive success and survival. Turbidity also degrades water quality by reducing light penetration, pH and oxygen levels, and the buffering capacity of the water. Degraded water quality may continue far downstream from the point where erosion occurs.

Use of areas along streams for equipment cleaning and staging can also have adverse impacts on stream water quality and negatively affect aquatic species. Runoff from such areas may contain pollutants and toxicants such as grease, oil, petroleum, de-icing solutions and detergents. These substances may result in mortality to aquatic organisms, or they may accumulate in their body tissues and result in subsequent adverse chronic effects.

Collection and relocation activities would call for removing crayfish, if present, from the proposed project vicinity. These activities would involve wading in streams, moving rocks, logs and other debris, and capturing Nashville crayfish with seines and dip nets. Individuals would be handled, held in buckets or coolers, and relocated to suitable, upstream habitat away from project-related disturbance and adverse effects. The duration of the collection and relocation activities can be presumed to occur over a short time period of several hours within a one day period. Although collection and relocation is the most effective means of minimizing project effects to Nashville crayfish from unavoidable, instream, project-related activities, such activities would also result in effects to the species.

An analysis of the direct and indirect effects of the proposed action on the species and/or critical habitat and its interrelated and interdependent activities are included under the "Analyses for effects of the action" in this biological opinion.

Proximity of the action:

The action area is located within the known, occupied range of the species, but is not located within any critical habitat area for Nashville crayfish or any other federally listed species. The proposed action would occur at two individual sites on two unnamed tributaries to Mill Creek in southeastern Davidson County, Tennessee. The action area is primarily comprised of the two stream channels, riparian corridor and portions of the floodplain. A network of major highways

15

- and streets, the Nashville Metropolitan Airport, the Middle Tennessee Mental Health Institute and other major urban developments lie adjacent to the action area. The proposed action would be implemented in the immediate and near vicinities of known occurrences of Nashville crayfish (O'Bara 1999; Tennessee Department of Environment and Conservation 2013, Withers, personal communication, 2013).

Distribution:

The action area would encompass the project footprint and all other areas where the Nashville crayfish would be directly and indirectly affected by the proposed action. The action area would: 1) total approximately 184,986 ft2 (4.3 ac), 2) include approximately 168,496 ft2 (3.9 ac) of aquatic area below the OHW (averaging approximately 14 ft wide in the unnamed tributary containing SLN, 10 ft wide in the unnamed tributary containing SLS and 85 ft wide in Mill Creek), 3) include approximately 16,490 ft2 (0.4-ac) of terrestrial area above the OHW, comprised of streambank and floodplain areas, 4) begin approximately 165 ft upstream of McGavock Pike on the unnamed tributary including SLN (where captured crayfish would be released), and extend downstream approximately 339 ft (0.06-mi) to the stream's confluence with Mill Creek, 5) begin approximately 165 ft upstream of McGavock Pike on the unnamed tributary including SLS (where captured crayfish would be released), and extend downstream approximately 271 ft (0.05-mi) to the stream's confluence with Mill Creek, and 6) approximately 1,848 ft (0.35-mi) of Mill Creek downstream from Mill Creek's confluence with the unnamed tributary encompassing SLS. The Service has defined the project action area based on an assessment of where direct effects would occur and the estimated distance that indirect effects would extend downstream of the proposed action. Based on available survey data and species occurrence records, the Service assumed in a recent programmatic consultation (draft) with the Corps that approximately 25% of the stream miles in the Mill Creek drainage contain suitable habitat for the Nashville crayfish (U.S. Fish and Wildlife Service 2012). Therefore, in regards to the proposed action, the Service believes that Nashville crayfish are randomly distributed in pockets of suitable habitat throughout approximately 25% of the 168,496 ft2 of aquatic area (42,124 ft [0.97-ac]) within the action area.. Information contained in species occurrence records (O'Bara 1999; Tennessee Department of Environment and Conservation 2013) and obtained via a species expert (Withers, personal communication, 2013) assisted the Service in defining the action area.

The project footprint would include a total of approximately 23,946 ft2 of aquatic and terrestrial areas. Approximately 7,456 (0.17-ac) of the project footprint would include aquatic areas below the OHW on the two unnamed tributaries affected by the action where the existing wingwalls would be removed and new wingwalls installed, and where proposed Nashville crayfish collection and relocation activities would occur. The remaining 16,490 ft2 (0.38-ac) of the project footprint would occupy terrestrial areas above the OHW where streambanks, terraces and the floodplain would be disturbed, vegetation would be removed and temporary equipment staging areas would be constructed.

16 Timing:

The proposed action can be divided into essentially three periods, a pre-construction phase, construction phase and an operations (post-construction) phase. Juvenile Nashville crayfish and/or Nashville crayfish eggs could potentially be affected during the pre-construction and construction phases. If collection and relocation of crayfish (pre-construction phase) or proposed work activities (construction phase) would occur during their reproductive period (mating, spawning, egg release, and egg incubation and hatching from October 1 to May 3 1.) or when Nashville crayfish hatchlings would occupy the action area (late spring and early summer), juveniles could be affected. However, the project proponent has not indicated a desire to conduct instream work activities during these time periods. Therefore, the Service believes the action would result in no effects to the species during its reproductive period or when hatchlings would be present in the action area. Adult Nashville crayfish could occur year-round at the proposed project site, and therefore, could potentially be affected at any time of year during the pre-construction and construction phases.

The operations (post-project) phase of the proposed action (installed and functioning wingwalls) would occur year-round into the foreseeable future and could potentially affect Nashville crayfish at various life stages if failures occurred at the wingwall replacement sites (e.g., head- cutting, streambank sloughing, substrate redistribution, and structural damage, settling or shifting of wingwalls, etc.).

Nature of the effects:

It is possible that the proposed action could have a variety of effects on individual Nashville crayfish. Depending upon when proposed project construction would occur, the Nashville crayfish's life cycle could potentially be disturbed or disrupted. The pre-construction and construction phases would be expected to result in temporary effects, whereas effects during the operations phase of the proposed project would likely be minor, but would be unknown without adequate post-project monitoring.

This proposed project could potentially result in the following effects to Nashville crayfish:

(a) direct injury or mortality as a result of individuals being collected and/or handled during the relocation process;

(b) direct injury or mortality as a result of individuals accidently not being removed from the project footprint during collection and relocation and being physically impaired or crushed due to the removal of existing wingwalls and placement/construction of new wingwalls;

(c) direct injury or mortality as a result of turbidity and/or deposition of sediment, created by construction activities (accumulated sediment washing downstream upon removal of existing wingwalls, erosion and runoff of soils on streambanks from foot traffic and potential contact of wingwalls with streambanks upon

17 removal or placement, etc.) obstructing crayfish gills, and reducing their ability to feed or respire;

(d) direct injury or mortality as a result of pollutants (spills of petroleum products from hydraulic, fuel and power systems, etc.) from construction equipment (crane used to remove existing wingwalls and install new wingwalls, concrete trucks, etc.) accidentally entering the streams, affecting water quality and food sources in the immediate project vicinity, and in turn their respiration and feeding capabilities;

(e) direct injury or mortality as a result of becoming physically impaired from accidental spills or leakage of concrete into the two unnamed tributaries to Mill Creek during construction of the new wingwalls, obstructing crayfish gills, and reducing their ability to respire;

(f) indirect injury as a result of turbidity and/or deposition of sediment from removal and placement/construction of wingwalls, and/or streambank disturbances from construction activities (foot traffic and potential contact of wingwalls with streambanks upon removal and placement) compelling individuals downstream of the proposed wingwall replacement sites to relocate to less suitable habitat;

(g) indirect injury or mortality as a result of pollutants (spills of petroleum products from hydraulic, fuel and power systems, etc.) entering the stream from construction equipment (crane used to remove existing wingwalls and install new wingwalls, concrete trucks, etc.), affecting water qu'ality and food sources, and in turn respiration and feeding capabilities of individuals downstream of project construction;

(h) indirect injury due to future impacts to habitat as a result of failures at the wingwall replacement sites (head-cutting, streambank sloughing, substrate redistribution, and structural damage, settling or shifting of wingwalls, etc) during the operations phase obstructing crayfish gills, and reducing their ability to respire;

(i) indirect injury as a result of being disrupted from their normal behavior patterns (including breeding, feeding or sheltering) and becoming stressed;

(j) indirect injury or mortality due to relocated crayfish competing with existing resident crayfish for shelter and food, increasing their susceptibility to predation and/or starvation.

Duration:

During the pre-construction phase, potential effects to Nashville crayfish would be temporary. Collection, handling, holding and relocation of Nashville crayfish would only occur over a several hour period.

18 During the construction phase, effects to Nashville crayfish are anticipated to be temporary in nature. Effects associated with removal of existing wingwalls and placement/construction of new wingwalls in the two unnamed Mill Creek tributaries would be temporary. Accidental spills of petroleum products from hydraulic, fuel and power systems, etc. of equipment during construction could result in temporary effects to the species that should cease after several days.

The effects of potential operational changes would not be known until sufficient post-project monitoring is conducted to determine if the proposed wingwall replacements result in any effects to Nashville crayfish or their habitat. The operational phase could potentially include a combination of temporary, long-term duration and/or permanent effects. Temporary effects might include, increased turbidity levels downstream of newly installed wingwalls during the first several days of operation. Long-term or permanent effects might include changes in stream hydraulics as a result of improper siting of the wingwalls. Failure (head-cutting, streamban.k sloughing, substrate redistribution, and structural damage, settling or shifting of wingwalls, etc.) of the project during the operations phase could result in either temporary effects (a brief episode of turbidity and/or sedimentation to downstream locations caused by minor, temporary erosion), long-term (continued turbid conditions and flushes of sediment covering habitat downstream due to ongoing stability issues), or permanent (the character of the stream channel would be permanently changed due to catastrophic bank failure).

Disturbance frequency:

Any disturbances to Nashville crayfish during the pre-construction and construction phases are anticipated to be restricted to a several day period. Collection, handling, holding and relocation of Nashville crayfish would be a one-time occurrence over a several hour period.

The proposed construction activities have the potential to temporarily alter conditions like flow and water quality (turbidity, sediment deposition and accidental spills of petroleum products), but overall would only produce these effects over several days and likely return to pre-project conditions within several days following construction.

Disturbances produced during the operational phase would be associated with routine operations and maintenance of the new wingwalls, or the result of post-project failure at or downstream of wingwall replacement sites. Disturbances during the operations phase could vary in frequency from a one-time event, multiple occurrences, frequent occurrences or be continuous, depending upon the nature of the disturbance (e.g., disturbance frequency associated with streambank failure and subsequent downstream turbidity and sedimentation could be continuous if bank sloughing was ongoing).

Disturbance intensity:

The disturbance intensity would be highest in the project footprint where: (a) Nashville crayfish would be captured and relocated during the pre-construction phase, and (b) the existing wingwalls would be removed and new wingwalls placed/constructed during the construction

19 phase. Such activities would potentially have the greatest risk of mortality or injury to the Nashville crayfish. The disturbance intensity during the construction phase would be lower in downstream areas because crayfish habitat would be greater distances from project construction.

It is anticipated that the operational disturbance intensity from the proposed project would be low because wingwalls currently exist at the proposed construction sites and will essentially be replaced with in-kind structures. Therefore, no additional Nashville Crayfish habitat should be lost due to installation of new wingwalls.

In general, the total number of Nashville crayfish affected by pre-construction, construction and operational phases of the proposed project would be very small, relative to the range-wide population in the Mill Creek system. Of those, only a very small percentage would be affected as a result of exposure to higher disturbance intensities.

Disturbance severity:

The disturbance severity of the pre-construction phase (collection, handling, holding and relocation of Nashville crayfish) would be minimal since it would be temporary and only occur in the immediate vicinities of the proposed wingwall replacement sites within the two unnamed Mill Creek tributaries.

The disturbance severity of the project construction phase would be minimal because (a) instream work would be very limited; the project proponent has indicated that "existing wingwalls will be removed with as minimal disturbance as necessary, the area surrounding the forms will .be dug by hand and no instream construction is proposed" (AMEC Environment and Infrastructure, Inc. 2012a; AMEC Environment and Infrastructure, Inc. 2012b), and (b) the total area of direct instreãm disturbances would be a very small area (approximately 7,456 ft' [0.17- ac]) relative to the range-wide geographic distribution of the species in the Mill Creek system, and (c) adequate and properly functioning BMPs would be expected to minimize construction- related disturbances to crayfish.

The disturbance severity of the operations phase would be minimal because: (a) the magnitude of disturbance related to operational aspects of the proposed project would be low, and the scope of the action relative to the range-wide geographic distribution of the species in the Mill Creek system would be small, and (b) wingwalls currently exist at the sites proposed for placement/construction of new wingwalls in the two unnamed Mill Creek tributaries, so installation of new wingwalls should not significantly alter stream hydraulics and any additional habitat loss would be negligible. Therefore, effects to Nashville crayfish from operation of the wingwalls, if any, would be minimal.

20 Analyses for effects of the action

Beneficial effects:

No wholly beneficial effects have been identified or are expected to occur. The proposed action would result in adverse effects to Nashville crayfish within the action area.

Direct effects:

Nashville crayfish would need to be present in the immediate vicinity of the proposed project sites in order to be directly affected by the proposed action. Improper collection and handling of individuals could result in direct injury or mortality. This would include accidentally injuring or killing crayfish with sampling gear (seines, dip nets or block nets could be detrimental to crayfish attempting to pass through mesh and become impinged in openings), by stepping on them during collection efforts, and/or holding them out of water or in a crowded collection container for too long of a period.

Direct effects to Nashville crayfish from construction activities (removal and placement/construction of wingwalls) in the project area could be possible because some individuals may not be detected, removed from the project vicinity and relocated out of harm's way prior to construction. Such activities could result in crayfish accidently being crushed or physically impaired (e.g., loss or damage to chelipeds, pereopods, swimmeret appendages, etc.) by workers, or wingwalls when being removed and installed/constructed, resulting in injury or mortality. Proposed construction work could also increase turbidity and/or sediment deposition in the streams, obstructing the gills of crayfish, and reducing their ability to feed and/or respire, resulting in injury or mortality.

Instrearn work could increase turbidity and/or sediment deposition in the streams. Activities associated with construction on adjacent streambanks (foot traffic, removing riparian vegetation, etc.) could cause bank erosion and also result in turbid instream conditions and/or sediment deposition from runoff. These instream and near stream activities would directly affect Nashville crayfish by obstructing their gills and reducing their ability to feed and/or respire, resulting in injury or mortality.

Direct effects to Nashville crayfish could occur as a result of pollutants (spills of petroleum products from hydraulic, fuel and power systems, etc.) accidentally entering the stream from construction equipment (cranes, cement trucks, etc.) in the project area, affecting water quality and food sources, and in turn respiration and feeding capabilities, resulting in injury or mortality.

If the proposed wingwalls would be poured in place, Nashville crayfish could be directly affected by accidental spills or leakage of concrete into the two unnamed tributaries to Mill Creek, obstructing crayfish gills and reducing their ability to respire, resulting in injury or mortality.

21 The Service estimates that it is probable that Nashville crayfish could be directly affected by the proposed action because records indicate that Nashville crayfish have been found within the action area in the immediate vicinity of the box culvert at SLN and near the action area at sites in Mill Creek, approximately 0.2-mi upstream of the Mill Creek confluence with the unnamed tributary containing SLS and approximately 0.6-mi downstream of the Mill Creek confluence with the unnamed tributary containing SLN (O'Bara 1999; Tennessee Department of Environment and Conservation 2013; Withers, personal communication, 2013). Therefore, based on this information, we assume that the species could potentially occur in the direct effect area.

In summary, the following direct effects to the Nashville crayfish are possible:

Injury or mortality as a result of handling and collection of individuals during capture and relocation.

2. Injury or mortality as a result of them being crushed or becoming physically impaired due to instream work activities.

3. Injury or mortality as a result of turbidity and/or deposition of sediment, created by construction activities and work activities on adjacent streambanks, obstructing crayfish gills, and reducing their ability to feed and/or respire.

4. Injury or mortality as a result of pollutants from the project's construction equipment accidentally entering the stream, affecting water quality and food sources, and in turn respiration and feeding capabilities.

5. Injury or mortality as a result of concrete accidently entering the stream, obstructing crayfish gills and reducing their ability to respire.

Interrelated and interdependent actions:

No interrelated and interdependent actions have been identified for this project.

Indirect effects:

Any Nashville crayfish in the action area downstream of the proposed project sites could potentially be indirectly affected by proposed construction activities (removal and placement/construction of wingwalls) and/or activities associated with construction on adjacent streambanks (foot traffic, removing riparian vegetation, etc.). Those instream and near stream activities could result in suspended sediments being transported by flows to downstream areas and disturb occupied Nashville crayfish habitat by creating turbid conditions and/or depositing sediment on substrate, compelling individuals to relocate to less suitable habitat, resulting in injury.

22 Nashville crayfish in the action area, downstream of the proposed project site, could also be indirectly affected by accidental spills of petroleum products from hydraulic, fuel and power systems entering the stream, resulting in injury or mortality. This could occur as a result of petroleum products accidentally entering the stream from the proposed project's construction equipment (cranes, cement trucks, etc.) in the staging area and operating above or near the stream, affecting water quality and food sources, and in turn respiration and feeding capabilities of Nashville crayfish, resulting in injury or mortality.

Nashville crayfish in the action area could be indirectly affected during the operations phase. If post-construction failures occurred at the wingwall replacement sites (head-cutting, streambank sloughing, substrate redistribution, and structural damage, settling or shifting of wingwalls, etc.) during the operations phase, turbidity and/or sediment deposition levels in the two unnamed Mill Creek tributaries could increase, obstructing the gills of crayfish and reducing their ability to respire, resulting in injury.

Nashville crayfish, removed from the project footprint and relocated upstream of the construction sites, or crayfish that would move on their own to escape project disturbances, could be indirectly affected. The crayfish could be relocated to sites where resident Nashville crayfish already occur, increasing completion for breeding, food and shelter, stressing individuals, resulting in injury. Those that would move of their own accord might relocate to sub-optimal habitat, increasing their susceptibility to predation and/or starvation, potentially affecting their long-term survival, resulting in injury or mortality.

The Service believes that indirect effects from the proposed action could potentially lead to individual Nashville crayfish being affected within the action area. However, those indirect effects would not significantly reduce the Nashville crayfish population level in the action area or reduce recovery of the species.

In summary, the following indirect effects to the Nashville crayfish are possible:

Injury as a result of turbidity and/or deposition of sediment, created by construction activities and associated work activities adjacent to the stream, compelling individuals downstream of construction sites to relocate to less suitable habitat.

2. Injury or mortality as a result of pollutants (spills of petroleum products from hydraulic, fuel and power systems, etc.) accidentally entering the stream from construction equipment near the work sites, affecting water quality and food sources, and in turn, respiration and feeding capabilities of Nashville crayfish downstream of the proposed action.

3. Injury as a result of post-construction failures at the wingwall replacement sites increasing turbidity and/or sediment deposition levels, causing obstruction of crayfish gills, reducing their ability to respire.

23 4. Injury as a result of being relocated to areas already occupied by resident Nashville, increasing completion for breeding, food and shelter, stressing individuals crayfish and disrupting from their normal behavior patterns.

5. Injury or mortality as a result of individuals, disturbed by construction activities, relocating of their own accord to sub-optimal habitat, increasing their susceptibility to predation and/or starvation.

Species' response to a proposed action

Numbers of individuals/populations in the action area affected:

While no Nashville crayfish were observed by the project proponent's consultants during their September 25, 2012, surveys of the proposed project sites (AMEC Environment and Infrastructure, Inc. 2012a; AMEC Environment and Infrastructure, Inc. 2012b), they have been found within the action area in the recent past. Two juvenile and two adult Nashville crayfish were found in the action area downstream of the box culvert at SLN and in Mill Creek at the confluence with the unnamed tributary containing SLN on July 8, 2005 (Tennessee Department of Environment and Conservation 2013; Withers, personal communication, 2013). As previously described in the "Status of the species within the action area", additional Nashville crayfish have been observed in Mill Creek at two sites in the near vicinity of the action area, approximately 0.2-mi upstream of the Mill Creek confluence with the unnamed tributary containing SLS and approximately 0.6-mi downstream of the Mill Creek confluence with the unnamed tributary containing SLN on various dates from 1998 through 2009 (O'Bara 1999; Tennessee Department of Environment and Conservation 2013). Therefore, based on past occurrence records of the species within or in the near vicinity of the action area, we believe the species currently occurs throughout the action area.

Sensitivity to change:

Nashville crayfish, which would be moved during collection and relocation efforts, or crayfish, which would move of their own accord due to project disturbances, could be forced to reoccupy sub-optimal habitat, potentially affecting their long-term survival.

Suspended sediments and/or deposition of sediment from proposed project activities could obstruct crayfish gills, reducing their ability to respire or feed. However, crayfish, including Nashville crayfish, have the ability to swim to other areas to avoid water quality disturbances and associated potential effects under most circumstances.

Nashville crayfish hatchlings could occupy the action area during late spring through early summer and be at risk if they became separated from their mothers, because they lack the ability to independently relocate outof harm's way during their first few weeks of life.

24 Resilience:

Resilience relates to the characteristics of populations or a species that allow them to recover from different magnitudes of disturbance. The Nashville crayfish is assumed to be a resilient species, given its persistence in the highly impacted Mill Creek watershed. Assuming that habitat conditions in the action area would not appreciably change as a result of pre-construction (relocation of individuals), construction and operation of the proposed project (magnitude of disturbance would likely be low), the Nashville crayfish would be expected to recolonize the areas disturbed by the proposed action.

Recovery rate:

In this biological opinion, the recovery rate relates to the time required for a Nashville crayfish population to return to equilibrium after exposure to a disturbance. Following completion of the instream disturbance, the project would not be expected to produce conditions appreciably different than current conditions, and the recovery rate for Nashville crayfish is expected to occur fairly rapidly (within one to two years).

CUMULATIVE EFFECTS

Cumulative effects include the effects of future state, tribal, local, or private actions that are reasonably certain to occur in the action area considered in this biological opinion. Future federal actions that are unrelated to the proposed action are not considered in this section because they require separate consultation under section 7 of the Act.

The action area is located within the Mill Creek watershed in Davidson County, Tennessee. This area continues to undergo significant development. Past activities have been implemented within or in the near vicinity of the action area by local and private entities that have impacted the two unnamed Mill Creek tributaries and mainstem Mill Creek and affected native fauna (as previously described in this opinion under "Factors affecting species environment within the action area"); such activities had no federal involvement. We are reasonably certain that additional similar activities are likely to occur in the future, and cumulative effects from those activities are likely to continue into the foreseeable future at a comparable pace. Such future developments would further affect the Nashville crayfish and its habitat within the currently proposed project's action area. Development of additional properties and construction of more roadways could also increase stormwater runoff into the stream reach within the action area. Therefore, cumulative effects, as defined by the Act, are expected to occur.

25 CONCLUSION

(NOTE: This biological opinion does not rely on the regulatory definition of "destruction or adverse modification" of critical habitat at 50 C.F.R. 402.02. Instead, we have relied upon the statutory provisions of the Endangered Species Act to complete the following analysis with respect to critical habitat.)

After reviewing the current status of the Nashville crayfish, the environmental baseline for the action area, and the effects of replacing eight wingwalls at two concrete box culvert crossings in two unnamed tributaries to Mill Creek on McGavock Pike in Davidson County, Tennessee, it is the Service's biological opinion that the proposed project within the Mill Creek watershed in Davidson County, Tennessee, as proposed, would not likely jeopardize the continued existence of the Nashville crayfish because: 1) the proposed action area would be small relative to the species range, and therefore, include only a small fraction of their overall population, 2) potential direct effects would be temporary and of short duration, and 3) the likelihood of lethal take would be low with properly engineered and correctly installed structures, adherence to BMPs and relocation of individual Nashville crayfish to similar, nearby habitat. No critical habitat has been designated for this species; therefore, none would be affected.

INCIDENTAL TAKE STATEMENT

Section 9 of the Act and federal regulation under section 4(d) of the Act prohibit the take of endangered and threatened species, respectively, without special exemption. Take is defined as to harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect, or to attempt to engage in any such conduct. Harm is further defined by the Service to include significant habitat modification or degradation that results in death or injury to listed species by significantly impairing essential behavioral patterns, including breeding, feeding, or sheltering. Harass is defined by the Service as intentional or negligent actions that create the likelihood of injury to listed species to such an extent as to significantly disrupt normal behavior patterns which include, but are not limited to, breeding, feeding, or sheltering. Incidental take is defined as take that is incidental to, and not the purpose of, the carrying out of an otherwise lawful activity. Under the terms of section 7(b)(4) and section 7(o)(2), taking that is incidental to and not intended as part of the agency action is not considered to be prohibited taking under the Act provided that such taking is in compliance with the Terms and Conditions (T&Cs) of this Incidental Take Statement.

The measures described below are non-discretionary, and must be undertaken by the Corps, so that they become binding conditions of any grant, permits or contracts, as appropriate, for the exemption in section 7(o)(2) to apply. The Corps has a continuing duty to regulate the activity covered by this Incidental Take Statement. If the Corps (and ultimately their Permittee, Metro): (1) fails to assume and implement the T&Cs or (2) fails to adhere to the T&Cs of the Incidental Take Statement through enforceable terms that are added to the grant, permit or contract, the protective coverage of section 7(o)(2) may lapse. In order to monitor the effect of incidental

26 take, the Corps must report the progress of the action and its effect on the species to the Service as specified in the Incidental Take Statement. [50 CFR § 402.14 (1)(3)].

AMOUNT OR EXTENT OF TAKE ANTICIPATED

The Service expects incidental take of Nashville crayfish would be difficult to detect for the following reasons: 1) the Nashville crayfish is a small, secretive animal, spending much of its life under cover on the bottom of streams, impoundments and overflow pools (under rocks, logs, in bedrock crevices, etc.); (2) locating a dead or injured individual would be difficult; and (3) if a dead or injured individual were found, it would be difficult to attribute death or injury to a particular project-related activity.

However, incidental take of Nashville crayfish can be anticipated from collecting and relocating individuals and from loss or degradation of habitat as a result of project construction activities and is expected to be in the form of lethal, harm, harass or capture. The Service believes that if Nashville crayfish are present in the impact area of the proposed action (project footprint), collection and relocation efforts and/or destruction or alteration of habitat within the impact area would result in incidental take of the species. While we cannot, at this time, quantify such take, we do request that the Corps require Metro, to monitor the removal and relocation sites and level of habitat disturbance with the following assumptions: Nashville crayfish would be collected for relocation from approximately 62 ft of the project construction areas in each of the unnamed Mill Creek tributaries to Mill Creek (including the estimated 30-ft culvert lengths), and approximately 112 ft of stream length immediately downstream of the construction area in the tributary containing SLN to the stream's confluence with Mill Creek and 44 ft of stream length immediately downstream of the construction area in the tributary containing SLS to the stream's confluence with Mill Creek. The OHW in the unnamed tributary including SLN has been estimated by the Service to average approximately 14 ft throughout the 174-ft stream length (62 ft of construction area + 112 ft of length downstream of the construction area) where Nashville crayfish would be collected; the OHW in the unnamed tributary including SLS has been estimated by the Service to average approximately 10 ft throughout the 106-ft stream length (62 ft of construction area + 44 ft of length downstream of the construction area) where Nashville crayfish would be collected. Therefore, the total area where crayfish would be collected for relocation is estimated to be approximately 3,496 ft2 (174 ft x 14 ft) + (106 x 10 ft). The Service recently estimated that approximately 25% of the stream miles in the Mill Creek drainage contain suitable habitat for the Nashville crayfish (U.S. Fish and Wildlife Service 2012). Therefore, assuming that 25% of the 3,496 ft' area where Nashville crayfish would be collected for the proposed project contains suitable habitat for the species, suitable habitat exists throughout 874 ft2 (3,496 ft2 x 0.25).

Relocation of the species into areas already occupied by crayfish upstream of proposed construction on the two unnamed tributaries to Mill Creek would also result in take. Crayfish vigorously defend territories. Crayfish introduced into those areas would likely be displaced and may not find suitable cover. Those individuals could disperse throughout another 3,496 ft2 of 27 stream to find habitat. The Service estimates that all Nashville crayfish in approximately 10% of the removal and reintroduction areas [(3,496 ft 2 + 3,496 ft') x 0.10] or 699 ft 2 would be taken in the form of lethal, harm, harass or capture.

Approximately 7,456 ft2 of aquatic area within the proposed project's footprint would be located below the OHW in the two unnamed Mill Creek tributaries affected by the action (approximately 4,746 ft2 in the tributary including SLN and 2,710 ft 2 in the tributary including SLS). The Service estimates that all Nashville crayfish in approximately 2% of the total aquatic portion of the project footprint (7,456 ft2 x 0.02) or 149 ft2 would accidentally not be collected during the relocation effort and would be taken in the form of lethal take during removal of the existing wingwalls and placement/construction of the new wingwalls.

In summary, the Service estimates that all Nashville crayfish on 699 ft 2 of stream bottom in the two unnamed tributaries to Mill Creek would be taken in the form of either lethal, harm, harass or capture as a result of proposed collection and relocation efforts (pre-construction activities); more specifically, crayfish in approximately 10% of those areas (70 ft 2) would be taken in the form of lethal; crayfish in approximately 30% of those areas (210 ft 2) would be taken in the form of harm; crayfish in approximately 30% of those areas (210 ft 2) would be taken in the form of harass; crayfish in approximately 30% of those areas (210 ft 2) would be taken in the form of capture. The Service further estimates that all Nashville crayfish on 149 ft 2 of stream bottom in the two unnamed tributaries would be taken in the form of lethal as a result of proposed construction activities (refer to Table 2 below).

Table 2. How the incidental take will be monitored if the specific number of individuals cannot be determined.

SPECIES CRITICAL PROJECT TAKE HABITAT

HABITAT PHASE TYPE Nashville crayfish N/A Pre-Construction Lethal All individuals in 70 ft2 of the project footprint Nashville crayfish N/A Pre-Construction Harm All individuals in 210 ft2 of the project footprint Nashville crayfish N/A Pre-Construction Harass All individuals in 210 ft2 of the project footprint Nashville crayfish N/A Pre-Construction Capture All individuals in 210 ft2 of the project footprint Nashville crayfish N/A Construction Lethal All individuals in 149 ft2 of the project footprint 11 TOTAL 1 849 ft' ___~i 28 In the "Analyses for Effects of the Action" section, the Service determined that the proposed action would result in incidental take of Nashville crayfish in several forms including:

(a) lethal from: 1) handling and collection of individuals during capture and relocation, 2) instream work activities crushing individuals, 3) increased turbidity and/or deposition of sediment as a result of instream work activities and work activities on adjacent streambanks obstructing crayfish gills and reducing their ability to feed and/or respire, 4) accidental spills of petroleum products from the project's construction equipment entering the streams, affecting water quality and food sources, and in turn respiration and feeding capabilities, 5) concrete accidently entering the stream, obstructing crayfish gills and reducing their ability to respire, and 6) individuals, disturbed by construction activities, relocating of their own accord to sub-optimal habitat, increasing their susceptibility to predation and/or starvation;

(b) harassment from: 1) handling and collection of individuals during capture and relocation, 2) increased turbidity and/or deposition of sediment as a result of instream work activities and work activities on adjacent streambanks obstructing crayfish gills and reducing their ability to feed, 3) accidental spills of petroleum products from the project's construction equipment entering the streams, affecting water quality and food sources, and in turn reducing feeding capabilities and feeding opportunities, 4) increased turbidity and/or deposition of sediment as a result of construction activities compelling crayfish downstream of construction sites to relocate to less suitable habitat, 5) relocating individuals to areas already inhabited by resident Nashville crayfish, increasing competition for breeding, food and shelter, stressing individual crayfish and disrupting their normal behavior patterns, and 6) individuals, disturbed by construction activities, relocating of their own accord to sub-optimal habitat, increasing their susceptibility to predation;

(c) harm from: 1) handling and collection of individuals during capture and relocation, 2) instream work activities resulting in physical impairment, 3) increased turbidity and/or deposition of sediment as a result of instream work activities and work activities on adjacent streambanks obstructing crayfish gills and reducing their ability to feed and/or respire, 4) accidental spills of petroleum products from the project's construction equipment entering the streams, affecting water quality and food sources, and in turn respiration and feeding capabilities, 5) concrete accidently entering the stream, obstructing crayfish gills and reducing their ability to respire, 6) increased turbidity and/or deposition of sediment as a result of construction activities compelling crayfish downstream of construction sites to relocate to less suitable habitat, 6) post-construction failures at the wingwall replacement sites increasing turbidity and/or sediment deposition levels, causing obstruction of crayfish gills, reducing their ability to respire, 7) relocating individuals to areas already inhabited by resident Nashville crayfish, increasing

29 competition for breeding, food and shelter, stressing individual crayfish and disrupting their normal behavior patterns, and 8) individuals, disturbed by construction activities, relocating of their own accord to sub-optimal habitat, increasing their susceptibility to predation;

(d) capture from: 1) handling and collection of individuals during capture and relocation, and 2) relocating individuals to areas already inhabited by resident Nashville crayfish, increasing competition for breeding, food and shelter, stressing individual crayfish and disrupting their normal behavior patterns.

EFFECT OF THE TAKE

In the accompanying biological opinion, we determined that the level of expected take is not likely to result in jeopardy to the species and would not result in destruction or adverse modification of critical habitat.

Previous biological opinions, completed for Nashville crayfish populations within Tennessee, which identified incidental take have been included in the table in Appendix A.

REASONABLE AND PRUDENT MEASURES

The Service believes the following reasonable and prudent measures (RPMs) are necessary and minimize effects of incidental take of the Nashville crayfish:

1. The Corps must ensure that the proposed action will occur as designed, planned, and documented in the biological assessment, all supporting information provided by Metro and this biological opinion.

2. The Corps must ensure that Metro implements measures to minimize or eliminate effects from pre-construction and construction activities.

3. The Corps must ensure that Metro monitors the proposed action to document potential changes in instream habitat conditions and stream channel function resulting from the project, and Nashville crayfish occurrences.

TERMS AND CONDITIONS

In order to be exempt from the prohibitions of section 9 of the Act, the Corps and Metro must comply with the following T&Cs, which carry out the RPMs described above. These T&Cs are non-discretionary.

30 The Corps and Metro will implement the proposed action as described in the biological assessment, the biological assessment's supporting documentation and this biological opinion. This T&C supports RPM 1.

2. All project construction shall be completed expeditiously, and riparian and instream conditions shall be restored as close to pre-project conditions as possible. This T&C supports RPM 2.

3. The Corps and/or Metro shall insure that no instream work occurs from October 1 through May 31, so that reproductive activities [i.e., mating, spawning, egg release, and egg incubation and hatching] are not affected by pre-construction or construction activities and that potential effects to hatchlings are minimized. This T&C supports RPM 2.

4. Crayfish will be collected and relocated in the two unnamed tributaries to Mill Creek within one hour of installation of block nets. Block nets will be maintained as needed (debris will be cleaned from them, and they will be checked frequently to insure that they are spanning the stream and remain in an upright position with lead lines secured to the bottoms of the stream). If crayfish become impinged in the mesh openings of block nets, they will be gently removed to minimize harm. Block nets will remain in place until project construction is completed to prevent crayfish from reentering the project footprint. If difficulties arise with keeping block nets upright and across the streams during project construction, Metro will immediately contact the Corps and Service and discuss optional approaches (construction of coffer dams, etc.). This T&C can be disregarded if no water is present in the streams at the time of collection and relocation. This T&C supports RPM 2.

5. Within the 24-hour period prior to any permitted work, a qualified biologist shall collect all Nashville crayfish observed from the project footprint in the two unnamed tributaries to Mill Creek (in the immediate vicinity of the existing box culverts and wingwalls) and from McGavock Pike downstream to both streams' confluences with Mill Creek. Captured crayfish (Nashville crayfish and all other species) will be relocated into suitable habitat a minimum of 165 ft upstream of the furthest upstream block net. Crayfish in collection buckets will be closely monitored to prevent stress from crowding. Water in collection buckets will be changed as needed to maintain overall water quality and ensure that it is the same or close to temperatures at the capture sites and acclimated to the temperature at the release sites by gradually adding water from the release sites. If a crayfish appears to be severely stressed or impaired, that individual will be held until it recovers sufficiently and not released until there is some certainty that it will survive when placed back into the stream.

Electrofishing "will not" be employed as a collection method to minimize potential injury and mortality to crayfish. Seining and dip netting will be

31 acceptable methods of collecting Nashville crayfish. If crayfish become impinged in the mesh openings of seines or dip nets, they will be gently removed to minimize harm.

A report must be provided to the Corps summarizing collection and removal activities of the species, which will include the number, form (I or II), estimated age class and sex of Nashville crayfish collected and relocated, note any observations of gross deformities, describe any injuries or mortality (incidental take) due to relocation efforts, identify Oollection and relocation sites (specify coordinates and measured areas), and state other crayfish species encountered and the number observed/collected. A biologist shall be present during all Nashville crayfish relocation activities and available as needed to monitor project construction activities. The Service's TFO in Cookeville, Tennessee (telephone: 931/528-6481), can provide a list of qualified aquatic biologists to assist with identifying Nashville crayfish and its habitat, collecting and relocating Nashville crayfish, and monitoring construction activities upon request. This T&C supports RPM 2.

6. Removal of riparian vegetation will be kept to a minimum. Following completion of construction activities, disturbed streambanks will be immediately replanted with native tree and shrub species, and/or native or close equivalent grass species. Streambanks will be inspected, and replanted as needed, until vegetation is successfully reestablished. Metro will not be required to plant native warm- season grasses or any plants which require a seed drill and excessive time and maintenance for establishment. The Service's TFO in Cookeville, Tennessee (telephone: 931/528-6481), Davidson County, Tennessee, Soil and Water Conservation District (telephone: 615/880-2030), or University of Tennessee Extension Davidson County (telephone: 615/862-5995) can be contacted for assistance in selecting the appropriate plant species and can provide information regarding planting methods. Metro will provide the Corps and Service with a list, including the number of each tree and shrub species planted and pounds of each grass species seeded, at the project sites within 60 days of project completion. This T&C supports RPM 2.

7. An aquatic biologist or hydrologist will be present to monitor pH levels in the streams during pouring of any concrete in or near the two unnamed Mill Creek tributaries. If spillage or leakage of concrete into either stream is observed, pouring will cease immediately and will not resume until the source of the spill or leak is found, the Service is notified about the spill or leak, and corrective action is taken to prevent further spillage or leakage. This T&C supports RPM 2.

8. Erosion control devices such as, but not limited to, fiber mats, silt fencing, instream silt curtains, rock filter dams, brush barriers, and silt basins shall be used, as appropriate, to prevent stream sedimentation. Appropriate silt controls will be installed at project construction sites prior to commencement of proposed

32 project construction. Controls will be used singly or in combination to maximize control of sediment runoff. Silt controls will be maintained and inspected regularly by Metro to ensure proper function. Any fill materials removed (existing wingwalls, etc.) during construction can be temporarily placed outside of the active flow channel at a minimum distance of the first terrace until all construction has been completed, but will need to be transported off-site following completion of project construction. Use of bioengineering methods (soft, vegetative approaches) is preferred for long-term stabilization of streambanks and is recommended over excessive use of hard structures (e.g., riprap) to minimize potential impacts to Nashville crayfish and other aquatic organisms, water quality, and riparian and instream habitats. Bioengineering techniques might include, but not be limited to, use of geotextile fabrics, layering with willow cuttings, construction of brush mattresses, fascines or vegetated geogrids, joint-planting willows into riprap, and use of a stinger to plant cuttings on upper streambanks. The Corps can provide technical assistance regarding erosion and silt control devices and various bioengineering approaches. This T&C supports RPM 2.

9. All heavy equipment and trucks will be cleaned, refueled and stored when not in use in designated staging areas, located a minimum of 300 ft from the OHW. This T&C supports RPM 2.

10. Each piece of heavy equipment will carry at least one oil-absorbent boom of 15- gallon capacity or greater when operating within or near streams. The boom(s) will be used to capture any accidental spills of petroleum products from the equipment's hydraulic, fuel and power systems. As a first line of defense, daily inspections of equipment (to check for potential leaks of petroleum products and drilling fluids) will occur, be documented in a log book and available to review upon request. This T&C supports RPM 2.

11. The Corps and Metro will coordinate with the Service's TFO to develop post- construction monitoring protocols to determine any changes in habitat conditions and/or effects of the project to Nashville Crayfish within the action area. This T&C supports RPM 3.

12. The Corps will ensure post-construction monitoring at the two project sites is conducted within a two-year timeframe. The purpose of the monitoring will be twofold: 1) to ensure conditions within the project footprint have been restored to acceptable conditions, so that Nashville crayfish habitat quality and amount is comparable to conditions present prior to permitted construction, and 2) to determine whether Nashville crayfish are able to persist throughout the action area. Monitoring should occur and be documented relatively soon after completion of construction. However, restored habitat must remain stable and undisturbed through at least one high flow event before any monitoring is initiated. This T&C supports RPM 3.

33 Upon locating a dead, injured, or sick individual of an endangered or threatened species, initial notification must be made to the Fish and Wildlife Service Law Enforcement Office at 220 Great Circle Rd, Nashville, Tennessee (telephone: 615/736-5532). Additional notification must be made to the U.S. Fish and Wildlife Service, Tennessee Ecological Services Field Office at 446 Neal Street, Cookeville, Tennessee. Care should be taken in handling sick or injured individuals and in the preservation of specimens in the best possible state for later analysis of cause of death or injury.

The RPMs, with their implementing T&Cs, are designed to minimize the effect of incidental take that might otherwise result from the proposed action. The Service believes that no more than all Nashville crayfish within 849 ft2 of suitable habitat will be incidentally taken. If, during the course of the action, this level of incidental take is exceeded, such incidental take represents new information requiring reinitiation of consultation and review of the RPMs provided. The federal agency must immediately provide an explanation of the causes of the taking and review with the Service the need for possible modification of the RPMs.

Table 3. The incidental take reduced, based on the best available commercial and scientific information, as a result of the implementation of the RPMs. SPECIES Project Take Project Take RPM Lowered Phase Type

Nashville crayfish All individuals in 70 ft2 Pre- Lethal All individuals in 35 of the project footprint Construction ft2 of the project footprint Nashville crayfish All individuals in 210 Pre- Harm All individuals in 105 ft2 of the project Construction ft2 of the project footprint footprint Nashville crayfish All individuals in 210 Pre- Harass All individuals in 105 ft2 of the project Construction ft2 of the project footprint footprint Nashville crayfish All individuals in 210 Pre- Capture All individuals in 105 ft2 of the project Construction ft2 of the project footprint footprint Nashville crayfish All individuals in 149 Construction Lethal All individuals in 75 ft2 of the project ft2 of the project footprint footprint

TOTAL 425 ft2

34 CONSERVATION RECOMMENDATIONS

Section 7(a)( 1) of the Act directs federal agencies to use their authorities to further the purposes of the Act by carrying out conservation programs for the benefit of endangered and threatened species. Conservation recommendations are discretionary agency activities to minimize or avoid adverse effects of a proposed action on listed species or critical habitat, to help carry out recovery plans or to develop information.

We offer the following conservation recommendation for consideration:

The Corps should coordinate with Metro and other entities requiring federal CWA Permits in the Mill Creek drainage well in advance of proposed actions to develop conservation banks and other measures to assist in recovery of Nashville crayfish and their habitat.

2. The Corps should make a concerted effort to utilize existing programs to raise awareness and promote conservation of the Nashville crayfish among private landowners, permit applicants and non-federal entities carrying out actions in the Mill Creek drainage. Mill Creek and its tributaries are under heavy pressure from development that could alter much of the aquatic habitat in the drainage and potentially drive the species to extinction. Outreach activities would be invaluable in making residents and developers in the drainage aware of the Nashville crayfish and the need to protect aquatic habitat in the Mill Creek drainage.

3. The Corps should provide funds to assist with conducting presence/absence surveys in the Mill Creek drainage to better determine the current status of Nashville crayfish throughout its range. Such information would be valuable in determining sensitive areas where additional protective measures would be warranted, contributing toward recovery of the species.

In order for the Service to be kept informed of actions minimizing or avoiding adverse effects or benefiting listed species or their habitats, the Service requests notification of the conservation recommendations carried out.

REINITIATION NOTICE

This concludes formal consultation on the actions outlined in the consultation request. As written in 50 CFR Section 402.16, reinitiation of formal consultation is required where discretionary Corps involvement or control over the action have been retained (or is authorized by law) and if: (1) the amount or extent of incidental take is exceeded; (2) new information reveals effects of the Corps' actions that may affect listed species or critical habitat in a manner or to an extent not considered in this biological opinion; (3) the Corps' action is later modified in

35 a manner that causes an effect to the listed species or critical habitat not considered in this biological opinion; or (4) a new species is listed or critical habitat designated that may be affected by the action. In instances where the amount or extent of incidental take is exceeded, any operations causing such take must cease until reinitiation.

For this biological opinion the incidental take would be exceeded when the take exceeds 849 ft2 of Nashville crayfish habitat, which is what has been exempted from the prohibitions of section 9 by this biological opinion. The Service appreciates the cooperation of the Corps during this consultation. We would like to continue working with you and your staff regarding this project. For further coordination please contact Todd Shaw of my staff at 931/525-4985.

Mary E. Jeni{iigs, FKI Supervisor 9 Date

36 REFERENCE

Acquistapace, P., L. Aquiloni, B.A. Hazlett and F. Gherardi. 2002. Multimodal communication in crayfish: sex recognition during mate search by male Austropotamobiuspallipes. Can. J. Zoo!. 80:2041-2045. 10.1139/z02-171.

AMEC Environment and Infrastructure, Inc. 2012a. Biological Assessment, The Nashville Crayfish (Orconectes shoupi), Project No. 56 1430006.0003, Metro Water Services Bridge Replacement, State Asylum Road - FEMA PDA 666, Davidson County, Tennessee. 9pp with a figure and photos.

AMEC Environment and Infrastructure, Inc. 201 2b. Biological Assessment, The Nashville Crayfish (Orconectes shoupi), Project No. 561430006.0003, Metro Water Services Bridge Replacement, State Asylum Road - MWS Project, Davidson County, Tennessee. 9pp with a figure and photos.

Barrociere, L.J. 1986. The ecological assessment and distribution status of the Nashville Crayfish, Orconectes shoupi. Master's Thesis, Tennessee Technological University, Cookeville, Tennessee.

Bergey, E.A., S.N. Jones and D.B. Fenolio. 2005. Surveys and Studies of the Oklahoma Crayfish and the Grotto Salamander. Final Report. Oklahoma Biological Survey. The University of Oklahoma. 26pp, including appendix.

Bouchard, R.W. 1976. Investigations on the conservation status of freshwater decapod in the United States. Part II: Eastern North American Crayfish. Office of Endangered Species, U.S. Department of the Interior. 26pp.

Bouchard, R.W. 1984. Distribution and status of the endangered crayfish Orconectes shoupi (: ). U.S. Fish and Wildlife Service, Tennessee Cooperative Fisheries Research Unit, Tennessee Technological University, Cookeville, Tennessee. 2Spp.

Bouchard, R.W. 1988. Philadelphia Academy of Natural Sciences. Personal communication with Richard G. Biggins, U.S. Fish and Wildlife Service, Asheville Field Office, North Carolina, when developing the Nashville Crayfish Recovery Plan (1st Revision).

Carpenter, J. 2002. Density and Distribution of the Nashville Crayfish in the Mill Creek Drainage Basin. Biology Department, David Lipscomb University, Nashville, Tennessee. Submitted to the U.S. Fish and Wildlife Service, Cookeville, Tennessee. 4lpp.

Cook, S.B. and C.F. Walton, Jr. 2008. Habitat Characterization of the Nashville Crayfish (Orconectes shoupi) in Mill Creek Watershed, Tennessee. Final report submitted to the U.S. Fish and Wildlife Service. 88pp.

37 Galeotti, P., D. Rubolini, G. Fea, D. Ghia, P.A. Nardi, F. Gherardi and M. Fasola. 2006. Female freshwater crayfish adjust egg and clutch size in relation to multiple male traits. Proc. Biol. Sci. 273(1590):l105-1ll0.

Georgia College. 2012. of Georgia, Ecology and Life History. Available http://www.gcsu.edu/crayfishes/ecologyandlifehistory.htm (Accessed July 25, 2012).

O'Bara, C.J. 1999. The Distribution and Current Status of the Nashville crayfish (Orconectes shoupi). Submitted to U.S. Fish and Wildlife Service, Cookeville Office for Tennessee Technological University Center for the Management, Utilization and Protection of Water Resources. 44pp.

O'Bara, C.J., A.J. Korgi, and G.J. Stark. 1985. Final report, status survey of the Nashville crayfish (Orconectes shoupi). Report to U.S. Fish and Wildlife Service, Asheville, North Carolina.

O'Bara, C.J. and L. Mason. 1990. The re-location and evaluation of the protection and mitigation procedures for the Nashville crayfish. Sverdrup Corporation, Nashville, Tennessee. 23pp.

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Tennessee Department of Environment and Conservation. 2012. Proposed Final YEAR 2012 303(d) LIST. Cheatham Reservoir Watershed, pages 24-26. Division of Water Pollution Control, Planning and Standards Section. Nashville, Tennessee.

Tennessee Department of Environment and Conservation. 2013. Tennessee Natural Heritage Program database (accessed October 31, 2013).

U.S. Army Corps of Engineers. 1981. Water quality along Mill Creek. Nashville, Tennessee.

U.S. Army Corps of Engineers. 1984. Mill Creek, Wimpole Drive area, Nashville, Davidson County, Tennessee. Final detailed project report and environmental assessment. Nashville, Tennessee.

U.S. Army Corps of Engineers. 2013a. Clean Water Act Section 404, Removal-Fill Permit Application for File No. LRN-2011-01152; Section 7 Consultation for Proposed Maintenance (Wingwall Replacements at Two Road Crossings) within Two Unnamed Tributaries near Mile 9.3R. Mill Creek, Opposite Cumberland River Mile 194.4L, Davidson County, Tennessee, 3 pp with maps and figures.

38 U.S. Army Corps of Engineers. 2013b. Letter dated June 12, 2013, from Timothy A. Higgs, Acting Chief, Western Regulatory Section, Operations Division, Nashville District, Corps of Engineers, Nashville, Tennessee, to Mary Jennings, Field Supervisor, U.S. Fish and Wildlife Service, Cookeville, Tennessee, requesting initiation of formal consultation for File No. LRN-201 1-01152; Section 7 Consultation for Proposed Maintenance (Wingwall Replacements at Two Road Crossings) within Two Unnamed Tributaries near Mile 9.3R. Mill Creek, Opposite Cumberland River Mile I 94.4L, Davidson County, Tennessee,

U.S. Fish and Wildlife Service. 1987. Recovery plan for Nashville crayfish (Orconectes shoupi). U.S. Fish and Wildlife Service, Atlanta, Georgia.

U.S. Fish and Wildlife Service. 1989. Nashville Crayfish Recovery Plan (1st Revision). U.S. Fish and Wildlife Service. Atlanta, Georgia. i6pp.

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U.S. Fish and Wildlife Service. 2012. Draft removal/fill activities permitted by the Corps of Engineers in the Mill Creek drainage programmatic biological opinion. U.S. Fish and Wildlife Service, Tennessee Ecological Services Field Office, Cookeville, Tennessee. FWS Log No. 2009-F-0155. Currently under review by the U.S. Army Corps of Engineers, Regulatory Branch, Nashville District.

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Withers, D.I. 2009. Tennessee Division of Natural Heritage. Personal communication with Jim Widlak, U.S. Fish and Wildlife Service, Section 7 Biologist, concerning survey of Century City Pond in Nashville.

Withers, D.I. 2012a. Tennessee Division Of Natural Heritage. Personal communication with Todd Shaw, U.S. Fish and Wildlife Service Biologist, in July 25, 2012, e-mail regarding age that Nashville crayfish reach sexual maturity.

Withers, D. I. 2012b. Tennessee Division of Natural Heritage. Personal communication with Todd Shaw, U.S. Fish and Wildlife Service Biologist, in July 27, 2012, e-mail regarding average clutch size of Nashville crayfish.

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39 regarding Nashville crayfish observed in unnamed tributary to Mill Creek at SLN (86°41'23.584"W; 36°5'39.455"N) during July 8, 2005 survey.

40 APPENDIX A

The following list includes previous biological opinions, issued for adverse effect and completed for Nashville crayfish populations within Tennessee, which identified incidental take: OPINIONS INCIDENTAL TAKE CRITICAL HABITAT (year) NUMBER HABITAT 1994 No more than 25% of the N/A total number of individuals present in the project area 2002 No more than2% of the N/A total number of individuals present in the project area 2002 No more than 3 individuals N/A at each crossing 2002 N/A No more than 0.5-ac of suitable habitat 2003 None specified N/A None specified 2004 No more than 5 individuals N/A 2008 N/A No more than 0.2-ac of suitable habitat 2008 N/A No more than 03-ac of suitable habitat 2008 N/A No more than 320 ft of suitable habitat 2008 N/A No more than 320 ft of suitable habitat 2009 N/A No more than 3,145 If of Mill Creek affected, resulting in the loss of 315 if of suitable habitat 2009 N/A No more than 4,320 ft2 of habitat at Mill Creek crossings or 1,120 ft2 of habitat at the tributary crossings 2009 N/A No more than the Nashville crayfish occupying 215 ft2 of the bottom of the Sims Branch pond 41 2010 N/A No more than 1,260 ft2 of Nashville crayfish habitat 2011 No more than 20 individuals N/A Loss of 0.5% of per year as a result of suitable habitat collection, holding, and from which crayfish relocation are removed at all project sites per year 2011 No more than 2 individuals N/A 2012 N/A No more than 33,023 ft2 of Nashville crayfish habitat 2012 N/A No more than 603 ft2 of Nashville crayfish habitat 2012 N/A No more than 519 ft2 of Nashville crayfish habitat 2012 N/A No more than 532 ft2 of Nashville crayfish habitat 2012 N/A No more than 1,077 ft2 of Nashville crayfish habitat 2013 N/A No more than 2,082 ft2 of Nashville crayfish habitat 2013 N/A No more than 260 ft2 of Nashville crayfish habitat 2013 N/A No more than 1,275 ft2 of Nashville crayfish habitat

42