Stewards of the Lower Susquehanna, Inc.

RIVERKEEPER®

Nov. 9, 2011 VIA Federal E-Rulemaking Portal Martin Miller, Chief, Division of Endangered Species, U.S. Fish and Wildlife Service, Northeast Regional Office, 300 Westgate Center Drive, Hadley, MA 01035

RE: Comments for Status Review of the American Eel as Noticed at 76 Fed. Reg. 60431, Sept. 29, 2011

Dear Mr. Miller,

Stewards of the Lower Susquehanna, Inc. (“SOLS”) and the Lower Susquehanna RIVERKEEPER® offer these comments to the U.S. Fish and Wildlife Service (“USFWS”) concerning initiation of a status review of the American Eel to determine if listing is warranted.

For the reasons described below we believe that there is sufficient science supporting the listing the American Eel as Threatened under the United States Endangered Species Act, 16 U.S.C. §§ 1531 et seq.

I. Status of the American Eel

The American Eel (hereafter “American Eel” and “eel” interchangeably) is in steep decline across its range, particularly in the Susquehanna River Basin. This decline began early in the 20th century, accelerated in the 1980s, and has continued to current populations that demonstrate a decrease of exponential magnitude from the recent past. The Eel’s decline is based on the following factors:

• Loss of Habitat – American Eels have lost an estimated 84 percent1 of their habitat, much of it due to the operation of dams which impede or completely block migration, reducing or removing habitats available for spawning, feeding and growth. Further, dams have fragmented river habitats and changed upstream habitat by slowing water flow and changing temperatures. In addition, river habitat has been altered by changes in streambeds and banks and streamside vegetation, all of which are affected by the operation of dams.

• Overutilization – Commercial and recreational fisheries that harvest virtually

1 Busch et al 1998. Using spatial data from the EPA, dam locations from the U.S. Army Corps of Engineers, and eel 1 every stage of the American Eel throughout its habitat do so with little to no regard for population status.

• Inadequacy of Existing Regulatory Mechanisms – The only regulatory authority currently exercised is that of the Atlantic States Marine Fisheries Commission (“ASMFC”). That organization has been unable to effectively reverse the declines in eel recruitment, halt commercial and recreational take of eels, or implement consistent methods to accurately assess their population size. Other available authorities, such as that of the states and the Federal Energy Regulatory Commission (“FERC”), have exercised authority sporadically and are clearly insufficient to halt the decline of the species.

• Other Factors – Other documented factors adversely affecting American Eel populations include climate change, mortality and morbidity from acidification of stream flows, mortality and injury in hydroelectric turbines when mature eels are migrating downstream, and water-based contaminants such as Mercury and PCBs.

The comments below summarize the procedural history of the American Eel, population information, and describe existing threats to the species and its habitat. We believe, as described infra, that the best available science strongly indicates the appropriateness of listing the American Eel across its range. Alternatively, we believe the creation and listing a Distinct Population Segment is appropriate.

A. Procedural Background

The ASMFC requested on May 27, 2004, that the FWS and the NMFS undertake a status review of the American Eel based on significant population decreases in the St Lawrence River/Lake Ontario portion of the species’ range. At the same time the ASMFC requested evaluation of the appropriateness of a designating a DPS listing under the ESA as well as an evaluation of the entire Atlantic Coast American Eel population. The FWS responded that the American Eel was not likely to meet the discreteness element of the policy requirements due to lack of population subdivision. However, the FWS did undertake a range wide status review of the American Eel.2

On November 18, 2004, the FWS and the NMFS received a petition requesting the listing of the American Eel as a threatened species under the ESA. That petition cited destruction and modification of habitat, overutilization, inadequacy of existing regulatory mechanisms, and other natural and man-made factors (such as contaminants and hydroelectric turbines) as the threats to the species. Initially the FWS determined that the petition presented substantial information indicating that listing the American Eel may be warranted, however it later made a final determination that listing the Eel under the ESA was “not warranted.” The 2007 final rule published the following findings:

• The Eel has been extirpated from some portions of its historical freshwater habitat over the last 100 years, primarily from dam construction which blocks access; • There is evidence that Eel populations in freshwater habitats, and to a certain

2 U.S. Fish and Wildlife Service, 12-Month Finding on a Petition to List the American Eel as Threatened or Endangered, 72 Fed. Reg. 4967-4997 (Feb. 2, 2007). 2 degree estuarine habitats, has declined in some areas likely as a result of harvest or turbine mortality, or a combination of factors; • The Eel remains widely distributed over the majority of its historical range; • An indication of decline exists in yellow eel abundance, but recent glass eel recruitment trends, while variable, appear stable over the past 15 years; • The American Eel is highly resilient with the ability to occupy the broadest range of habitats within freshwater, as well as estuarine and marine waters, and it remains a widely distributed fish species; • Although roughly 25 percent of the Eel’s historical freshwater habitat is now inaccessible due to dams, the loss of this habitat does not threaten the species’ long-term persistence; • Roughly 75 percent of historic freshwater habitat remains and is occupied; • There is a substantial percentage of estuarine and marine habitat available to, and occupied by, the American Eel throughout its range; • Recreational and commercial eel harvests are not factors of concern at population level due to economics, species’ resilience, and existing regulatory mechanisms; • There is no information indicating that parasite and contaminant driven eel mortality during outmigration are currently causing or are likely to cause population level effects to the American Eel; • There is no information indicating that predation or competition with non-native species or mortality from turbines is causing population-level effects; • American Eel recruitment success is dependent on ocean conditions, and variable ocean conditions cause fluctuations in recruitment. However, because available information indicates that the species remains widely distributed and glass eel recruitment trends appear stable over the past 15 years, documented ocean conditions do not threaten the current population status of the American Eel; • There is no information to indicate that ocean conditions are likely to threaten the American Eel at a population level in the future.

The FWS indicated that its 2007 12-month finding was based on the contents of the submitted petition, existing literature, and information gathered during the status review that preceded the finding. During that time period the FWS identified as most relevant the stock assessments for the Atlantic Coast, the American Eel data assembled for the Canadian stock assessment and specific published research on life history and potential threats. In addition, the 12-month finding stated that the review focused on available data within the North American Continent.

The 12-month finding referenced two workshops in which over 25 scientific experts participated. Expert panelists included a broad, diverse range of scientific perspectives relevant to the status review of the American Eel. Those panelists had expertise on threats, or life history characteristics associated with threats, to the American Eel. The FWS asked these panelists questions and used their responses to gauge the likelihood of eel extinction based on the information presented.3

B. American Eel General History

3 Draft Minutes, American Eel Great Lakes/Canada Threats and Population Dynamics Workshop, U.S. Fish and Wildlife Service in cooperation with National Marine Fisheries Service January 31 – February 2, 2006, Buffalo, New York and FWS. 2006. Draft Minutes from the American Eel Status Review Workshop 2: Great Lakes/Canada threats and population dynamics. Buffalo, NY, January 31-February 2, 2006. 3

American eel (Anguilla rostrata) are found in fresh, brackish, and coastal waters from the southern tip of Greenland to northeastern South America (Facey and Van den Avyle 1987). American eel are ubiquitous in many habitats (Jacobs et al. 2003), and can contribute up to more than 25% of the total fish biomass in some individual systems (Smith and Sauders 1955; Ogden 1970). In Connecticut rivers and streams, the American eel was found in one case to be four times more abundant than any other species (Jacobs et al. 2003).

American eel habitats include the open ocean, estuaries, large coastal tributaries, rivers, small freshwater streams, lakes, and ponds. They utilize habitats from the East Coast of North America and the northern portion of South America, into the inland areas of the Mississippi River and the Great Lake drainages (primarily Lake Ontario), and north into Canadian tributaries. American eel are sometimes found in land locked lakes, particularly in the northeastern United States (Facey and Van den Avyle 1987). The latitudinal range for the American eel has been documented as 5°N to 60°N (Bertin 1956), and their range covers approximately 30,000 km of coastline (Federal Register 2007). American eel are thought to occupy the broadest array of habitats of any fish in the world (Helfman et al. 1987).

American eel are a catadromous species that reproduces in salt water, and after an oceanic larval stage, migrates to brackish or fresh water for growth to maturity. Upon reaching maturity, the American eel migrate back to the ocean to spawn. Spawning occurs in the winter and spring in the Sargasso Sea, and the newly hatched larvae (pre- leptocephalus and leptocephalus stages) passively drift and swim toward the continental shelf where they metamorphose into glass eels (Kleckner and McCleave 1982; Kleckner and McCleave 1985; McCleave et al. 1987). The transformation from a leptocephalus larvae into a glass eel includes a decrease in body length and weight due to a loss in water concentration, an increase in body thickness, loss of larval teeth, darkening of the eye, changes in the morphology of the head and jaw, and further development of the digestive system (Fahay 1978). Glass eels are miniature transparent American eel that are morphologically similar to elvers (the next life stage), but they are unpigmented. As American eel develop pigment, some begin to migrate into freshwater. These young pigmented American eel are termed elvers. Some elvers remain in coastal rivers and estuaries, while others may continue movements upstream in the winter and the spring (Facey and Van den Avyle 1987). In fact, upstream migration may continue into the yellow- phase for at least three to five years (Haro and Krueger 1991).

The next life stage for American eel is the yellow-phase, which is the primary growth stage where individuals spend most of their lives. The yellow-phase is characterized by a lack of sexual maturity and may last many years. Sexual differentiation begins primarily during the yellow-phase. Following sexual differentiation, American eel eventually begin to migrate downstream (Krueger & Olivera 1999). Yellow-phase eels gradually metamorphose into silver-phase adults through a process that involves a number of physiological changes.

Physiological changes reviewed by Facey and Van den Avyle (1987) include a change in color to a metallic bronze black sheen, pectoral fin color change from yellow- green to black, fattening of the body, thickening of the skin, increased length of capillaries in the rete of the swim bladder, and degeneration of the digestive tract. Additionally, the eyes become enlarged and the visual pigments in the eye are altered 4 (Vladykov 1973; Beatty 1975). These changes better suit the American eel for migration at deeper depths (Beatty 1975; Kleckner and Kruger 1981; Facey and Van den Avyle 1987). During maturation, American eel migrate downriver to marine waters and out to the Sargasso Sea, where they spawn once and die (Facey and Van den Avyle 1987).

All American eel comprise one panmictic population, meaning that they are a single breeding population that exhibits random mating. Thus, for example, an American eel from the northern portion of the range could mate with an American eel from the southern portion of the range, and their offspring could inhabit any portion of the range. As a result, recruits to a particular system are likely not the offspring of the adults that migrated out of that system (ASMFC 2000; Avise 2003).

Many studies indicate that American eel populations are declining (Castonguay et al. 1994 a, b; Haro et al. 2000b). Recent research by Richkus and Whalen (1999, 2000) show a decrease in yellow-phase and silver-phase American eel abundance in Ontario, Quebec, New York, and Virginia. For example, during the 31-day peak migration period in 2004, the mean number of American eel passing through the Moses-Saunders Hydroelectric Dam at Cornwall, Ontario, decreased from previous estimates of over 27,000 individuals per day to 274 individuals per day (Casselman In press).

Due to their diverse habitat requirements, American eel are subjected to a number of anthropogenic impacts. Fishing pressures and habitat loss are implicated as contributing factors in the American eel decline. Some habitat threats include blockage of stream access, pollution, nearshore habitat destruction, and oceanic changes (Castonguay et al. 1994a, b; ASMFC 2000).

a. Life Stages & Pertinent Specie Characteristics

American eel in the Northeast were documented arriving upstream from the end of March to the beginning of May (Facey and Van den Avyle 1987). Ricker and Squires (1974) and Sheldon (1974) reported that American eel ran in Maine from late April to June. In Rhode Island, migrations peaked during April and May (Facey and Van den Avyle 1987). Further south, in North Carolina, Rulifson et al. (2004) found that recruitment of elvers occurred from January through April, with the highest density of American eel present from March to April.

Glass Eel Glass eels enter estuaries by drifting on flood tides and holding position near the bottom of ebb tides (McCleave and Wippelhauser 1987), and by actively swimming along shore in estuaries above tidal influence (Barbin and Krueger 1994). Movements of glass eels are primarily nocturnal (Dutil et al. 1989). Eventually, glass eels in estuaries change into pigmented elvers (Haro 1991). Throughout the elver life stage, American eel are mostly active at night. During the day elvers either burrow or remain in deep waters (Deelder 1958). Elvers move back up into the water column on flood tides and return to the bottom during ebb tides (Pacheco and Grant 1973; McCleave and Kleckner 1985; McCleave and Wippelhauser 1987).

Factors that influence the daily abundance of migrating elvers include nightly tidal height, river water temperature and discharge, and the difference between bay and river temperatures (McCleave and Kleckner 1985; Sorensen and Bianchini 1986; Ciccotti et al. 1995; McCleave and Wipplehauser 1987; Wipplehauser and McCleave 1987; Martin 5 1995; Jessop 2003). Migration occurs in waves and is initially triggered by an increase in temperature to between 12 and 14°C. After initiating migration, temperature does not appear to have a functional influence on migrating elvers (Jellyman and Ryan 1983; Martin 1995; Jessop 2003). River discharge appears to control the daily abundance of upstream migrants, with decreases in abundance coinciding with increases in river discharge. Jessop (2003) stated that increased tidal height delivered an increased abundance of elvers to the river mouth. Temperature then triggered upstream migration, while discharge controlled the rate of movement upstream (Jessop 2003).

While most American eel elvers migrate into freshwater, some may cease migration in coastal waters and estuaries and remain there from the time they arrive until they reach the mature silver eel stage and begin the spawning migration (Morrison et al. 2003, Lamson et al. 2006). In addition to the upriver migration, fall and spring migrations have been documented (Smith and Saunders 1955; Medcof 1969).

Elver substrate associations Substrate is an important habitat parameter for juvenile American eel, as elvers have been seen burrowing during the day and in between movements upstream. American eel appear to use many different types of substrates. Facey and Van den Avyle (1987) stated that migrating elvers make use of soft undisturbed bottom sediments as shelter. Furthermore, a study by Edel (1979) demonstrated that American eel are less active when there is shelter present. Fahay (1978) stated that post-larval American eel are benthic and utilize burrows, tubes, snags, plant masses, other types of shelter, and the substrate itself. Elvers may also use the hydraulic boundary layer of rough substrates to facilitate migration upstream, or migrate through interstitial spaces within a substrate to avoid high water velocities during upstream migration (Barbin and Krueger 1994).

Elver water velocity/flow Sheldon and McCleave (1985) noted that in Penobscot, Maine, glass eels accumulated on the surface when surface currents on the ebb tide decreased below 15 cm·s-1. In another study, river discharge and its effects on water velocity were found to be the primary factor influencing the rate of elver upstream migrations (Jessop 2000). In velocities exceeding 35 to 40 cm·s-1, elvers had difficulty swimming and maintaining their position (McCleave 1980; Barbin and Krueger 1994). Jessop (2000) found that most elvers would not swim at water velocities exceeding 25 cm·s-1, and instead would remain resting in the substrate. Some researchers have found that delays or prevention of upstream elver migration can be caused by high flows (Lowe 1951; Jessop and Harvie 2003).

Yellow Eel

Geographic and temporal movement patterns Some yellow-phase American eel continue migrating upstream until they reach maturity, while others remain in the lower portions of coastal estuaries and rivers (Morrison et al. 2003; Cairns et al. 2004; Lamson et al. 2006). Morrison et al. (2003) studied the migration histories of yellow eels using otolith microchemistry. Yellow eels in the Hudson River, New York, showed three modes of habitat use: 1) the freshwater mode, in which yellow eels and elvers utilized only freshwater habitats; 2) the mixed mode, where American eel resided in freshwater for at least 2 years before migrating

6 back to brackish water; and 3) the brackish mode, where American eel remained entirely in brackish habitats, without ever utilizing freshwater environments (Morrison et al. 2003). Individuals that exhibited the brackish mode had increased growth rates, earlier maturation, and began their downstream migrations sooner than those that utilized freshwater habitats (Morrison et al. 2003; Cairns et al. 2004; Lamothe et al. 2000). These findings support the Helfman et al. (1987) hypothesis that brackish water habitats are more productive than freshwater for American eel.

Yellow eels remain in freshwater and brackish systems for up to 30 years before maturing into silver eels and migrating to the sea to spawn (Tesch 1977; Helfman et al. 1987; Able and Fahay 1998). Few young American eel are found in inland lakes (Hurley 1972; Facey and LaBar 1981); migrants to farther reaches upstream tend to be older, larger, more mature females (Helfman et al. 1987; Haro and Krueger 1991; Oliveira 1999; Morrison et al. 2003). American eel migrations upstream occur from March through October, and peak in May and July depending on location (Richkus and Whalen 1999). McGrath et al. (2003c) found that the numbers of American eel in the St. Lawrence River, New York, approaching the Moses- Saunders Power Dam peaked in early July and early October. Verdon et al. (2003) found that American eel in the Richelieu River, Quebec, began upstream migrations as early as June 11th and ended in late September. Hildebrand (2005) found that in the Shenandoah River, West Virginia, American eel utilized the eel ladder at Millville Dam from March through October (the duration of time that the ladder was installed).

There is substantial evidence that some American eel establish a home range. A home range is defined as the spatial extent or outside boundary of an animal's movement during the course of its everyday activities (Burt 1943). The size of the home range can be influenced by food availability, competition, and predator density (Bozeman et al. 1985). Ford and Mercer (1986) found some evidence of a home range and territoriality, and found that larger American eel were located primarily in large creeks, while smaller American eel were found in narrow creeks at the back of the marsh, in the Great Sippewisset Marsh, Massachusetts. They found that 93% of the American eel in their study traveled less than 100 m (Ford and Mercer 1986).

Habitat influence on sexual differentiation A prominent theory is that female American eel are found in freshwater, while males are found in estuaries (Vladykov 1966; Tesch 1977). Alternatively, Helfman et al. (1987) suggested that males were found in estuaries because these productive habitats led to fast growth. Females, on the other hand, preferred freshwater habitats that led to slower growth and increased fecundity (Helfman et al. 1987).

Other evidence suggests that density of American eel plays the key role in determining the sex of an individual; males are produced in high density areas, and females in low density areas. Thus, females are more common in upper reaches of rivers where density is lowest (Krueger and Oliveira 1999). Oliveira (1999) and Oliveira et al. (2001) hypothesize that males are produced in areas where crowding is occurring. Furthermore, males favor areas closer to the sea and spawning ground in more productive habitats, where they can grow and mature faster (Helfman et al. 1987). On the other hand, females tend to disperse widely within their range and utilize all suitable habitats. They favor slower growth and greater size, thus increasing fecundity and swimming ability (Krueger and Oliveira 1999; Goodwin and Angermeier 2003). In fact, in upper reaches of rivers, American eel tend to mature at older ages and larger sizes 7 (Helfman et al. 1987).

Yellow eel depth associations Thomas (2006) found that yellow-phase American eel in an impounded system typically occupied depths of 0.4 to 1.5 m (available depths of 0 to 2.93 m). In addition, while mean morning (1.1 m) and afternoon (1.1 m) depths were relatively shallow, mean evening (1.3 m) and night (1.4 m) depths were slightly deeper. Given the relatively shallow nature of the impounded system, these changes in depth usually represented areas with different substrate and variable distances from shore. Furthermore, mean winter (0.8 m) and spring (0.9 m) depths showed use of shallow habitat, while mean summer (1.2 m) and fall (1.3 m) depths showed use of deeper areas. Therefore, American eel utilization of different depth areas may be dependent upon time of day and season (Thomas 2006).

Yellow eel water velocity/flow Yellow eels are likely not water velocity dependent, as high densities of American eel have been found in lakes and ponds where velocity is low or nonexistent (K. McGrath, New York Power Authority, personnel communication). However, Wiley et al. (2004) found that in Maryland, velocity-depth diversity was the only stream habitat variable related to American eel density. The highest densities of eel occurred in sites that had four velocity-depth regimes: slow (<0.3 m/s)-deep (>0.5 m/s), slow-shallow (<0.5 m/s), fast (>0.3 m/s)-deep, and fast-shallow. Sites with only one of two velocity- depth regimes had significantly lower American eel densities (Wiley et al. 2004).

Silver Eel

Geographic and temporal patterns Once American eel enter their final life stage the maturation process accelerates and they migrate out to the Sargasso Sea to spawn. In New England tributaries, spawning migrations begin in the late summer and continue through fall. American eel migrate later in the Southeastern states and in the Mid-Atlantic than in the Northern states. It is hypothesized that this delay helps to synchronize the arrival of the American eel at the spawning grounds in the Sargasso Sea (Wenner 1973; Facey and Helfman 1985; Helfman et al. 1987).

Migration Silver eel migration begins at different times of year depending on location, but occurs primarily in the fall, although winter migrations have been documented (Facey and Helfman 1985; Euston et al. 1997, 1998). In Newfoundland, the largest American eel migrations occur in late September and early October (Bouillon and Haedrich 1985). McGrath et al. (2003a) found that American eel in the upper portion of the St. Lawrence River migrated downstream from the end of June to the beginning of October, and that the primary migration in the lower estuarine portion of the river occurred in October. Slightly south, Winn et al. (1975) documented American eel migrating in Rhode Island from September through November.

Migration of mature American eel is thought to occur mostly at night (Winn et al. 1975; Haro et al. 2000a; McGrath et al. 2003b). Haro et al. (2000a) stated that silver eels in the Connecticut River, Massachusetts, migrated primarily at night within several hours after sunset, and became inactive during the day. The variables thought to

8 influence downstream migration of silver eels include water temperature, river and stream discharge, odor, and light-intensity, including moon phase (Hain 1975; Westin 1990; Haro 1991; Richkus and Whalen 1999; Richkus and Dixon 2003).

Rainfall, which leads to increased river discharge, may also have an impact on silver eel migrations (Lowe 1951; Winn et al. 1975; Charles Mitchell & Associates 1995; Euston et al. 1997, 1998). Winn et al. (1975) noted increased migrations after rains, as well as during the third and fourth lunar quarter. Haro et al. (2003) found in Maine that more American eel were captured on, or soon after, days with rain than on dry days. The age and size at which migration begins varies geographically. American eel in the northern part of the range exhibit slower growth and remain longer in freshwater and estuarine systems before beginning migration back to sea (Facey and LaBar 1981).

Various studies in Newfoundland, Lake Ontario, and Lake Champlain have shown that American eel migrate back to sea after about 12 to 13 years, and at a mean size of 69 cm (Gray and Andrews 1971; Hurley 1972; Facey and LaBar 1981; McGrath et al. 2003a). In the southern part of their range, American eel begin migrating earlier than in the north (Hansen and Eversole 1984; Helfman et al. 1984; Owens and Geer 2003). Hansen and Eversole (1984) found that in the Cooper River, South Carolina, American eel older than 7 years old and greater than 65 cm in length were sparse, suggesting that adults migrate at a younger age and smaller size. Helfman et al. (1984) found similar results in the Altamaha River, Georgia. More recently, Owens and Geer (2003) found that populations in Virginia tidal rivers were comprised mostly of American eel less than 7 years old, indicating that either migrations had occurred by this age or elder populations had succumbed to some mortality factor.

C. Range

The American Eel’s range includes all accessible riverine and coastal areas to which western North Atlantic Ocean oceanic currents provide transport. (ASMFC 2000) Presently, the overwhelming majority of the American Eel population is located along the Atlantic seaboard of the United States and Canada. Historically the species was well distributed along the United States and Canadian Atlantic coast and inland.

a. Susquehanna River Basin Portion of the Eel’s Historic Range

Historically, the American Eel was extremely abundant throughout the Susquehanna River Basin. Fowler (1921) listed the eel as “abundant throughout all the waters of our state (Pennsylvania).” Among freshwater fish, this was second to sturgeon (2.75 million pounds) and ahead of shad at 1.3 million pounds (Pennsylvania State Commissioners of Fisheries 1883). These statistics are surely not reflective of the true abundance of eels at that time, but do present some indication of the commercial value of the fishery.

Eel catch, by county, in numbers, pounds, and dollar value was reported in the Department of Fisheries reports for 1909 to 1912 (Pennsylvania Department of Fisheries 1909, 1910, 1911, 1912). By subtracting the catch for counties in the Delaware and Potomac River drainages, it was possible to approximate the catch for the Susquehanna River. The catch of eels in numbers ranged from 53,824 to 336,761 per year with a mean of 157,070. In pounds, the catch ranged from 44,002 to 147,222 with

9 a mean of 88,339. Many small eels were captured in the fishery, as evidenced by the mean weight of 0.68 pounds per eel, meaning the river system was highly susceptible to elver and yellow eel upstream migration. For the four-year period, 1909 to 1912, 90 percent of the statewide catch in numbers and 86 percent of the catch in pounds was harvested in the Susquehanna River, although Delaware River harvest by New Jersey fishers was not reported.

b. Demise of the Susquehanna River Basin American Eel Population

Overfishing and pollution from lumbering, mining, and untreated sewage and loss of access to spawning and nursery habitat adversely affected migratory fish. In tributaries, migratory fish runs were blocked by hundreds of milldams. Specific information on the construction of these dams and their impact on migratory fish is difficult to obtain. However, concern for this impact is evidenced early on in state legislation. For example, the "Statutes at Large of Pennsylvania," for 1770 to 1771, chapter DCXXVII, was "AN ACT DECLARING THE RIVER SUSQUEHANNA AND OTHER STREAMS THEREIN MENTIONED PUBLIC HIGHWAYS, FOR IMPROVING THE NAVIGATION OF THE SAID RIVER AND STREAMS, AND PRESERVING THE FISH IN THE SAME." This act encompasses the Susquehanna River; the Juniata River to Bedford and Frankstown; the Conestoga River, upstream to Mathias Slough's milldam; and portions of Conodoguinet, Penns, Swatara, and Bald Eagle Creeks. Chapter DCXXIII of the Statutes at Large (same year) regulated the fisheries and provided for fish passage in the lower reaches of Codorus and Conewago Creeks in York County. Act 750, passed by the Pennsylvania Legislature in 1870, declared` the Conestoga River from its mouth to the confluence of Muddy Creek a public highway for the protection of fish.

Dams on the mainstem of the river were first constructed around 1830 to 1835 to feed the new Susquehanna canal system. Canal dams were located on the North Branch at Nanticoke, the Juniata at North's Island, and the mainstem at Duncan’s Island and Columbia (Gay 1892, Meehan 1897). The canal dams completely blocked migratory fish in some years, but allowed passage in others, particularly when the dams were damaged by ice flows. In 1866, the Pennsylvania Legislature passed an act requiring fish passage facilities to be constructed at the dams and appointed a Fish Commissioner (forerunner to what is now PFBC) to ensure compliance. The fishways constructed were largely ineffective, but enough fish passed by way of temporary dam breaches caused by ice damage to create optimism for the success of fish passage measures. By the end of the century, the canal system was abandoned, and breaks in the Columbia Dam re-opened a large portion of the river to migratory fish. Fisheries for migratory species reappeared in the lower Susquehanna and Juniata rivers until the early 1900s and Pennsylvania harvest at that time amounted to about 200,000 to 400,000 pounds per year (U.S. Fish Commission reports).

A low level (8 to 16') hydroelectric dam was constructed in 1904 at Conewago Falls near the village of York Haven (river mile 55). The first of the high dams, the Holtwood or McCalls Ferry project (55') at river mile 25, was completed in 1910. Although a powerhouse fish ladder and a west shore sluiceway were included at Holtwood, both were ineffective in passing migratory fish. For instance, after 1910, American shad fisheries in Pennsylvania disappeared and Maryland harvest in Cecil and Harford counties declined by two-thirds to an average 1.5 million pounds per year. Because of the lack of effective fish passage technology at high dams, it was determined that none would be required at the final two hydroelectric projects in the lower Susquehanna, the 10 100' high Conowingo Dam (river mile 10) completed in 1928 and the 75' high Safe Harbor Dam (river mile 32) completed in 1931. Except for the lowermost 10 miles of the Susquehanna River, what was once the largest and most productive American shad, river herring, and American eel producing river on the Atlantic Coast was closed to fish migrations and the production and benefit of the migratory fish stocks were lost.

In addition to eliminating migratory fish access to upstream spawning and nursery habitat, these dams also altered river habitat in a more permanent way by creating impoundments that inundated and eliminated riverine spawning and rearing habitat in the lower portion of the Susquehanna River. Conowingo, Holtwood, Safe Harbor and York Haven dams inundated 14, 8, 10, and 4 miles of habitat, respectively, resulting in the loss of 36 miles of riverine habitat. The Conowingo Reservoir (Conowingo Pool) extends to the Holtwood tailrace and the Holtwood Reservoir (Lake Aldred) extends to the Safe Harbor tailrace, resulting in a 32 mile stretch of impounded water with little flowing water habitat. Above Lake Clarke (the Safe Harbor impoundment) there is 15 miles of free-flowing river to York Haven Dam.

Hydroelectric project operations also negatively impact migratory fish habitat in the areas immediately downstream of the dams. The Susquehanna River hydroelectric projects (with the exception of York Haven) tend to generate power when it is most needed, during the daytime peak use period, and refrain from generation at night when water storage in the impoundment is replenished with incoming river flows. This results in unnatural flow conditions which can vary from flood to drought flow conditions within minutes during any given day. Few aquatic organisms are adapted to these drastic and abrupt fluctuations in flows, and the result is a highly perturbed aquatic ecosystem that is not suitable for migratory fish spawning, nursery habitat, or fish passage, particularly for eels who are sensitive to flow volumes.

Current American eel regulations in Maryland (including the lower Susquehanna River) permit commercial and recreational fishing for eels with no restrictions for eels larger than six inches. For eels less than six inches, there is a limit of 25 per person, per day. Commercial harvest of American eels in Maryland peaked at 1.3 million pounds in 1945, and then declined to 110,000 pounds in 1962. Harvest peaked again in 1981 at more than 700,000 pounds, but declined to an average of 100,000 pounds from 1982 to 1988. Between 1989 and 2007, total Maryland eel landings averaged nearly 300,000 pounds annually and now comprise over 40 percent of total Atlantic coastal landings (MDNR landings database, personal communication, Keith Whiteford).

Reported annual eel harvest since 1992 from Susquehanna River and Susquehanna Flats have totaled less than 1,000 pounds. However, an annual average harvest of 20,000 pounds (1992- 2007) has been reported for mainstem Chesapeake Bay -North of the Sassafras River. Some of these landings could be harvested from any of the 4 rivers above the Sassafras including the Susquehanna River. Current regulations in the Pennsylvania portion of the Susquehanna River drainage do not permit commercial harvest of eels but do permit recreational harvest. Eels between 6 and 8 inches may be harvested for bait with a year-round season and a 50 fish creel limit. Eels harvested for food have a minimum size of 8 inches, a year-round season and a creel limit of 50 fish. Current regulations in the New York portion of the Susquehanna River drainage allow for both commercial and recreational harvest of American eels. Year around eel harvest by recreational anglers is currently allowed subject to a 6-inch minimum size limit and a daily limit of 50. Commercial harvest is also permitted through special licenses issued at 11 the discretion of the NYSDEC. These licenses provide for the use of both eel pots and eel weirs.

D. Population Status

Data corroborating the continued decline of the American Eel throughout its range, and the near extirpation from the northern Chesapeake’s Susquehanna River Basin population, lends credence to listing the American Eel under the ESA.

a. Susquehanna River Basin Population

The Maryland Department of Natural Resources, Maryland Biological Stream Survey (MBSS) News- letter March 1999, Volume 6, Number 1 states:

"The most dramatic example of the decline of American eel abundance is dam construction on the Susquehanna River. The magnitude of this loss is corroborated by the decline in the eel weir fishery in the Pennsylvania portion of the Susquehanna River. Before the mainstem dams were constructed, the annual harvest of eels in the river was nearly 1 million pounds. Since then, the annual harvest has been zero. Given the longevity of eels in streams (up to 20 years or more) and their large size, the loss of this species from streams above Conowingo Dam represents a significant ecosystem-level impact. Because adult eels migrate to the Sargasso Sea to spawn and die -- transporting their accumulated biomass and nutrient load out of Chesapeake Bay -- the loss of eels has increased nutrient loads in the basin and reduced them in the open ocean where they are more appreciated."

“Although the Chesapeake Bay and tributaries support a large portion of the coastal eel population, eels have been essentially extirpated from the largest Chesapeake tributary, the Susquehanna River. The Susquehanna River basin comprises 43% of the Chesapeake Bay watershed. Construction of Conowingo Dam in 1928 effectively closed the river to upstream migration of elvers at river mile 10. Before mainstem dams were constructed, the annual harvest of silver eels in the Susquehanna River was nearly one million pounds. There is currently no commercial harvest (closed fishery in Pennsylvania) and very few fish (resulting from Pennsylvania Fish & Boat Commission stockings in the early 1980s) are taken by anglers above the dam. The Maryland Biological Stream Survey (MBSS) collects data in freshwater drainages of Maryland. Eel captures in this survey were collected for the Susquehanna River and tributaries in the vicinity of Conowingo Dam. This data reflects the fact that the dam blocks the upstream migration of eels. By extrapolating densities of eels captured in Maryland the MBSS survey estimated that there would be over 11 million eels in the Susquehanna watershed if their migration was not blocked by dams.”

This trend appears to be coastwide. Over-harvest and dam construction are serious threats (ASMFC 2000). Eels are harvested as glass eels, elvers, yellow eels and silver eels to support regional and European food markets, domestic troll line bait, and as small bait eels for domestic sport fisheries. Glass eels and elvers are harvested for culture to marketable size in Asia and have been sold for up to $600 per pound on the international market. Factors that contribute to the impacts of over-harvest include: American eels mature slowly, requiring 7 to 30+ years to attain sexual maturity; glass eels aggregate seasonally to migrate; yellow eel harvest is cumulative over multiple years, on the same

12 year class; and all eel fishing mortality is pre-spawning mortality. (ASMFC 2000).

We believe that the evidence provided below shows that all §4 factors are acting in concert to cause the American Eel’s steep decline in the United States, and therefore merits the species’ protection under the ESA.

II. Criteria For Endangered Species Act Listing

A. The Present Or Threatened Destruction, Modification Or Curtailment Of the Species’ Habitat and Range

1) Loss of Habitat or Range

The FWS estimated in its 2007 Final Determination that the available coastline from Maine to Texas is 29,612 km and stated that this broad range should provide the American Eel with a generous buffer against adverse conditions. That conclusion directly conflicts with evidence showing significant anthropogenic changes to the eel’s range which have reduced habitat in some places by nearly 100 percent.

For instance, states from New York to Virginia have experienced stream habitat reduced by 88 percent, and habitat from North Carolina to Florida reduced by 77 percent.4 Likewise, drainages in the Gulf of Mexico notwithstanding the Mississippi River Basin have seen significant habitat and population reductions.5 In the Mid- Atlantic, the American Eel has been nearly extirpated from its historically most productive habitat – the Susquehanna River Basin - due to upstream and downstream dam obstructions. The loss of this portion of range represents a significant gap in the range of the taxon because the Susquehanna River Basin comprises 43% of the Chesapeake Bay watershed that at one time was ideal American Eel habitat.

The loss of the American Eel’s range generally is dramatic, but is especially a cause for concern in the context of maturation, migration and reproduction. As discussed supra female American Eels spend most of their lives in freshwater habitat in tributaries to the Atlantic seaboard. Safe and efficient access to and from these freshwater habitats is critical to the survival of the American Eel. Minkinnen notes in his 2010 Final Report documenting American Eel presence at Conowingo Dam (the first and largest dam on the Susquehanna River just 10 miles upstream from the Bay proper) that “Susquehanna fish passage facilities were designed and sized to pass adult shad and herring and are not effective in passing juvenile eels upriver.”6 It is thus logical and empirically supported that with nearly nonexistent eel passage upstream on the Susquehanna, the vast Susquehanna River Basin habitat is de facto host to a rapidly declining, negative growth American Eel population separated physically from other eel habitat.

4 Atlantic States Marine Fisheries Commission Atlantic Coast Diadromous Fish Habitat: A Review of Utilization, Threats, Recommendations for Conservation, and Research Needs; Habitat Management Series #9 January 2009; Chapter 10. 5 NatureServe, 2004. Downloadable animal database. NatureServe Central Databases. Available from: http://www.natureserve.org/explorer/servlet/NatureServe?sourceTemplate=tabular_report.wmt&loadTemplate=species_RptCo mprehensive.wmt&selectedReport=RptComprehensive.wmt&summaryView=tabular_report.wmt&elKey=102540&paging=ho me&save=true&startIndex=1&nextStartIndex=1&reset=false&offPageSelectedElKey=102540&offPageSelectedElType=speci es&offPageYesNo=true&post_processes=&radiobutton=radiobutton&selectedIndexes=102540. 6 Minkkinen, Steve and Ian Park, “American Eel sampling at Conowingo Dam 2010,” Maryland Fishery Resources Office, 1- 15-2011. 13

During adult female eels’ downstream migration out of the Susquehanna watershed, it can be safely assumed from studies on other dams that Conowingo Dam and the other major hydroelectric dams upriver of Conowingo have a substantial and cumulative mortality rate. Studies on other dams in the U.S. and Canada have shown turbine mortality rates of the 3-foot female adult eels to be approximately 40 to 50%. If this is the base mortality rate for Conowingo, as well as Safe Harbor, York Haven and Holtwood Dams upriver, the cumulative mortality rates for downstream silver eels equals 78 to 88%. If over decades – as this is the life span of freshwater American Eel - we combine these survival rates for females passing all three dams we arrive at a sad figure of approximately 12 to 22% survival. When taken in combination with the lack of any upstream passage for new generations of elvers science unambiguously shows the collapse of a distinct portion of the American Eel population that once accounted for 25% of the fish biomass of the Susquehanna River Basin.

Estuarine river systems like the Susquehanna are the sole migratory pathways for female American Eels to gain access to their requisite habitats. Yet current anthropogenic changes to historical habitat has dramatically limited the amount of habitat available and disproportionately eliminated larger, more fecund females from arriving at the Sargasso Sea to spawn. Thus, losing a substantive portion of habitat like the Susquehanna River Basin, combined with the dramatic loss of riverine habitat along the Atlantic Seaboard, equates to reduced eel productivity and abundance. Although it is possible for eels to remain in saltwater habitats research has shown that behavior to be extremely rare, especially for females. Marine populations are at best small and represent an unquantified and unreliable basis for conserving and reviving the American Eel population.

B. Overutilization For Commercial, Recreational, Scientific Or Eduational Purposes

1) Commercial

The American Eel is commercially harvested in all stages of its life except larval stage. They are likewise harvested in all of their habitats: freshwater lakes and rivers, estuaries, Atlantic Ocean and Gulf of Mexico. Commercial eel fisheries are found in nearly every seaboard state from Maine to the Gulf of Mexico, as well as in several inland states excepting Alabama, Mississippi and Pennsylvania. Eels have been largely extirpated from the Mississippi and Susquehanna River Basin’s although they were once plentiful throughout these drainages.7

The American Eel is over-utilized across the species’ range in the United States. ASMFC (2000) states: “Harvest pressure and habitat loss … are the primary causes of decline in abundance of American Eel.” In addition to these causes 4 unique and critical factors contribute to adversely affecting eel populations: (1) American eel maturation is slow requiring at minimum 7 years and often 20+ years to attain sexual maturity; (2) glass eel aggregate seasonally to migrate; (3) yellow eel harvest is a cumulative stress, over multiple years, on the same year class; (4) all eel mortality is pre-spawning

7 MacGregor, R., A. Matthers, P. Thompson, J.M. Casselman, J.M. Dettermers, S. LaPan. T.C. Pratt, and B. Allen (2008), Declines of American Eel in North America: Complexities Associated with Bi-national Management. American Fisheries Society Symposium 62. 14 mortality. Id. Indeed, Pennsylvania only allows recreational take of eel because there is no substantive population left within its borders due to the near extirpation of the Susquehanna River Basin population as discussed supra.

The ASMFC’s 2008 Addendum II discusses the precipitous decline of the American Eel.8 That addendum notably posits that landings of yellow and silver eel in 2007 totaled 834,500 pounds, with New Jersey and Delaware each reported landings over 100,000 pounds of eel and Maryland reported landings over 300,000 pounds in 2007. Combined, these three states accounted for 73% of the coastwide commercial landings. Massachusetts, Pennsylvania, Georgia, Florida, and the District of Columbia were granted de minimis status for the 2007 commercial fishing year. De minimis status is approved if a member states’ commercial landings of yellow and silver eel for the previous year are less than 1% of the coast-wide landings for the same year. The ASFMC’s records readily show that the Commission has failed to undertake any protective measures within its authority to conserve remaining eels along the Atlantic seaboard. This failure is especially glaring in light of evidence showing dramatic range- wide declines for over a decade.

2) Recreational

The ASFMC’s American Eel reports discuss recreational harvest of American eel. According to those records domestic consumption of eel is low although foreign markets exist and are profitable. However, there is also a commercial fishery for eels that are used and sold as bait for sport fishing. Similarly, some recreational fisherman may catch eels as their own bait.

Much of the above data is new and was not available during the pendency and creation of the 2007 Final Determination. This information clearly documents the range- wide decline of American eel population without substantive data corroborating a different conclusion. The aforementioned information is substantial and, in conjunction with information already in the Service’s possession, should merit a 12-month status review.

C. Disease or Predation

1) The Swim Bladder Parasite A. Crassisus Is A Threat Which, Acting In Concert With Other Factors, Will Bring The American Eel Population Perilously Close to Extinction

The nematode, A. crassus, is native to Asia and is commonly found in Japanese eels, where it appears to cause little harm (Nagawasa et al. 1994). The parasite’s short life cycle, coupled with its high fecundity, ability to tolerate a wide range of salinities, and use multiple paratenic hosts to complete its lifecycle, makes it a highly successful invasive colonizer (Kennedy and Fitch 1990; Kirk 2003; Kennedy 2007). The first documented case of A. crassus in the United States occurred the mid-1990s in a Texas aquaculture facility and in wild eels in Winyah Bay, South Carolina (Fries 1996). Since then, it has been detected in almost all of the states along the Atlantic seaboard,

8 Atlantic States Marine Fisheries Commission, ADDENDUM II TO THE FISHERY MANAGEMENT PLAN FOR AMERICNA EEL, Approved October 23, 2008. 15 including Maine, Massachusetts, Rhode Island, Connecticut, New York, New Jersey, Delaware (John Clark, Delaware Department of Natural Resources and Environmental Control, personal communication), Maryland, Virginia, North Carolina, South Carolina, and Florida (Barse and Secor 1999; Barse et al. 2001; Moser et al. 2001; Geer 2003; Morrison and Secor 2003; Rulifson et al. 2004; Sokolowski and Dove 2006; Machut and Limburg 2008; Aieta and Oliveira In Prep). Reported infection rates in the United States range from 0 to 100% (Sokolowski and Dove 2006; Aieta and Oliveira In Prep). The parasite was also recently identified in New Brunswick and Nova Scotia, Canada, with the northernmost part of its range being documented as Cape Breton Island, Nova Scotia (Aieta and Oliveira In Prep).

The parasite is detrimental to the eel’s swim bladder and reported effects of the nematode include enlarged abdomens, swim bladder rupture, dilation of the blood vessels in the swim bladder, thickened swim bladder wall, skin ulcers in the abdomen, a red and swollen anus, secondary bacterial infections, decreased swimming ability, and mass mortality (van Banning and Haenen 1990, Molnár et al. 1991; Molnár et al. 1993; Molnár 1994; Ooi et al. 1996; Würtz et al. 1996; Nimeth et al. 2000; Würtz and Taraschewski 2000; Crean et al. 2003; Lefebvre et al. 2004; Gollock et al. 2005a; Sokolowski and Dove 2006). Recent research by Palstra et al. (2007a,b) also indicates that eels severely infected by A. crassus are unlikely to reach the spawning grounds. Sures and Knopf (2004) specifically noted the underappreciated threat A. crassus poses to eels on either side of the Atlantic. Their concern was rooted in the finding that this parasite inhibits the ability of eels to reach spawning grounds in the Sargasso Sea. A decrease in recruitment may occur if fewer eels are arriving at the spawning grounds, and this could lead to a further decrease in the eel population (Barse and Secor 1999; Palstra et al. 2007).

Furthermore, experiments conducted by Gollock et al. (2005) tested and proved the hypotheses that infected eels are more vulnerable to mortality when exposed to hypoxic conditions, and that an increased oxygen demand due to parasitism alters their physiological response to hypoxic stress. Although these experiments occurred on European Eels, the close relation and life histories to American Eels can be reasonably extrapolated to the American Eel. Similarly, experiments by Paistra et al. (2007a) tested and proved the hypothesis that parasitism by A. crassus can lead to failure of migrating eels to reach spawning grounds, and compromise the ability of those eels that do reach spawning grounds to reproduce. Those findings essentially showed that eels with high parasite levels or damaged swim bladders simply do not have the endurance or ability to complete a spawning migration, possessing less fat for egg or sperm production and less energy for the journey and avoiding predation.

Additional studies show that A. crassus infection inhibits vertical swimming ability of eels, and thus cannot travel at the varying depths necessary to migration. Chow et al. (2009). Another discovery concerns the tremendous energetic investment that eels make in reproductive tissues and how parasitic infection limits fat stores and thus fecundity. Chow et al. (2009); Belpaire et al. (2009). The cumulative effects of this parasite in combination with threats from hydroelectric, contaminants and low fat stores further lowers the ability of American Eels to successfully reach their spawning grounds and reproduce.

In its 2007 Final Determination the Service noted that it remains cautious of the implications of A. crassus due to the limited information it possessed documenting 16 reduced glass eel recruitment or like population level indicators showing probability of decline. The new information presented here posits the cumulative effects of A. crassus parasitism and other factors will lead to lost density in spawning areas that eels will be increasingly unable to reproduce. This “Allee effect” will further decrease species productivity and move the species that much closer to extinction (Allee 1931). This same biological mechanism was recently invoked in the extinction risk of the polar bear. (Molnar et al. 2008).

D. Inadequacy Of Existing Regulatory Mechanisms

There is a distinct dearth of planning for conservation of the American Eel in the United States. The Status of Fishery Resources of the Northeastern U.S. NEFSC – Resource Evaluation and Assessment Division Dec 20069 Report anticipates a stock assessment that has never occurred. Likewise, the U.S. Fish and Wildlife Service Strategic Plan Fiscal Year 2007 to 2011 Region 5 provides extremely limited discussion of eel conservation without offering any substantive plan or means for measuring the effectiveness of fish passage restoration efforts.

NMFS also gives short shrift to the American Eel in its recent and important policy document: Our Living Oceans: Habitat, Status of the Habitat of U.S. Living Marine Reosurces. Policymakers’ Summary (NMFS 2009). That report briefly outlines habitat impacts from dams and water withdrawals but fails to discuss the American Eel, the only catadromous fish in the United States. While the benefits of dam removal to eels and other fish are well documented (Conyngham et al, 2006), there remains a distinct lack of coordinated, systematic efforts to remediate the threat of dams to eels.

1) ASMFC Regulation Has Failed To Protect The American Eel From Decline

ASFMC’s mission is “[t]o promote the better utilization of the fisheries, marine, shell and anadromous, of the Atlantic seaboard by the development of a joint program for the promotion and protection of such fisheries, and by the prevention of physical waste of the fisheries from any cause.” Interestingly, ASFMC’s statement of ‘vision’ it to promote “[h]ealthy, self-sustaining populations for all Atlantic coast fish species or successful restoration well in progress by the year 2015.” Yet in practice the agency performs a consumptive mission allocating and organizing fishing stock and has repeatedly denied indicators of American Eel decline.

For example, it is well documented that freshwater habitat for the American Eel has been adversely modified by anthropogenic actions, yet the ASFMC has yet to take affirmative steps to stem eel mortality and decline, stating that “much of American Eel habitat has not been quantified,” and always qualifying indicators of decline by reiterating that “American Eels are habitat generalists, and therefore may be somewhat resilient to impacts on habitat availability.”10 These conclusory statements are unsupported by the vast majority of scientific data concerning the American Eel, are misleading, and inaccurate.

Even within the limited, but absolute, purview of the ASMFC in managing the Atlantic American Eel fishery ASFMC’s regulations and reporting have proven

9 http://www.nefsc.noaa.gov/sos/spsyn/op/eel/index.html 10 ASFMC 2009, Present Conditions of Habitat and Habitat Areas of Particular Concern for American Eel. 17 inadequate to address eel harvest. The Monterey Bay Aquarium reported in 2007 (Halpin 2007) that [e]xport data from the U.S. underscores the unreliability of capture data for eels…Looking only at fresh and frozen eels, exports have exceeded reported landings by as much as 949 percent.” Compounding such problematic accounting is the perpetual classification of the American Eel stock as “unknown.” While the ASFMC states it does not possess data of eel stock on one hand, it later concurs in its 2005 Stock Assessment Peer Review Panel Report that yellow eel abundance was at an historic low, which is an amazing conclusion when evidence shows eel decline by several orders of magnitude in a panmictic population. It is untenable for the organization tasked with tracking, managing and restoring the American Eel to continue to oversee silver eel harvests that are necessary to replenish stocks. For this very reason the ASFMC should defer to the management of the eel under the ESA to prevent this species from becoming endangered in the reasonably foreseeable future.

2) International Experts On The American Eel Agree That Inadequate Regulatory Mechanisms Exist To Protect The Species

Bi-national experts on the American Eel concur that existing regulatory efforts have failed to halt the decline of the eel: “Management actions aimed at protecting American Eel and European Eel have largely been unsuccessful in halting declines and rebuilding stocks as, until recently, actions have not been well coordinated at the appropriate scale in recognition of the unique life cycle of these species.” MacGregor et al. (2008).

MacGregor et al. (2008) describes the primary reasons the FWS failed to list the eel under the ESA in 2007, and offers a telling summation in favor of listing distinct population segments of the American eel, if not the entire species:

In the meantime, the FWS has determined that listing American eel as threatened or endangered is not warranted (Federal Register 2007). The finding was constrained by the need to demonstrate that American eel is in danger of extirpation within a significant component of its range, or likely to become an endangered species within the foreseeable future. Because of a lack of scientific information relation to population-level status of American eel and the best genetic information that the species is panmictic, the FWS concluded that range- wide persistence of American eel was not in doubt. The finding appeared to rely heavily on information suggesting that some American eel complete their life cycle in marine environments and on two short-term data series relating to glass eel abundance. The finding placed less emphasis on longer-term data series that illustrated declining trends in abundance of yellow and silver American eel. Unlike the Species at Risk in Canada, the ESA does not provide for designation and protection measure for species of special concern.

It is not within the scope of this paper to comment substantially on the official designation of American eel under species at risk legislation; however, we are compelled to comment that (1) numerous data series suggest American eel is in decline in significant components of its range, (2) substantial habitat has been lost, (3) numerous and significant sources of anthropogenic mortalities exist for American eel, and (4) American eel is semelparous with late onset maturity, particularly for the northern, more fecund segment of the population. Numerous threats have been identified, and their cumulative effects were not addresses in

18 detail within the 12-month finding, but they apparently have been substantial. The precipitous (99%) loss of recruitment to Lake Ontario and the Susquehanna river, the major declines in silver American eel landings in Quebec fisheries, the fact that yellow American eel are at or near historic lows within the ASFMC jurisdictions, and the 50% decline in the Chesapeake Bay VIMS index all point to significant cause for concern, regardless of designation as a species at risk. The lack of designation under the ESA should not be perceived as a reason for inaction. Waiting to take appropriate action until a species is threatened with extinction is not in the best interests of agencies, ecosystems, or stakeholders. Strong, coordinated management actions are required to reverse the decline of the American eel, actions that include habitat as well as fisheries management. Managers must also be mindful of the parallels between the experiences managing European eel and those of American eel.

Top scientists within the eel community agree the American Eel and other eel species face a substantial risk of endangerment and extinction. The 2003 Quebec Declaration of Concern states that the steep decline in eel populations - along the lines of 1% of major juvenile resources - endangers the immediate future of the species and requires immediate precautionary action. American Fisheries Society (2009). Likewise, the Addendum II to the ASFMC’s eel management plan “recommend[s] stronger regulatory language to improve upstream and downstream passage of American Eel to state and federal agencies” in light of the FWS 2007 Final Determination that listing the American Eel was not warranted. However, there are currently no regulatory mechanisms in place within the United States that adequately protect the American eel from extinction.

3) The United States Fish and Wildlife Service (FWS)

Section 18 of the Federal Power Act11 (“FPA”) grants the FWS legal authority to require the licensees of private hydroelectric facilities to provide safe and efficient upstream and downstream passage for American Eels in the historic range of the species. However, the FWS has declined to exercise its authority to conserve remaining American Eels of the Atlantic seaboard. Indeed, the FWS’ 2007 Final Determination deduced from scant and circumstantial evidence that listing the eel was not warranted.

4) The National Marine Fisheries Service (NMFS)

The FPA also grants NMFS legal authority to require the licensees of private hydroelectric facilities to provide safe and efficient upstream and downstream passage for American Eels in the historic range of the species. However, NMFS has declined to exercise its authority to conserve remaining American Eels of the Atlantic seaboard.

5) The Federal Energy Regulatory Commission (FERC)

Pursuant to the FPS, FERC has the legal authority to require licensees of private hydroelectric facilities to provide safe and efficient upstream and downstream passage for American Eels in the historic range of the species. However, FERC has declined to exercise its authority to conserve remaining American Eels of the Atlantic seaboard.

11 16 U.S.C. § 797(e). 19

For example, FERC is currently in the middle of a 5 year relicensing process for the Conowingo hydropower facility, the first of 4 hydroelectric facilities on the lower Susquehanna River, located approximately 10 miles north of the Susquehanna River’s terminus at the Chesapeake Bay. The current licensee seeking relicensing is Exelon Corporation. The current license for the Conowingo Project was issued on August 14, 1980 and expires on September 1, 2014. Exelon has applied for license renewal using the FERC’s Integrated Licensing Process (“ILP”). As part of the ILP, Exelon previously filed its Pre-Application Document (“PAD”) and Notice of Intent (“NOI”) (March 12, 2009), Proposed Study Plan (“PSP”) (August 24, 2009), Revised Study Plan (“RSP”) (December 22, 2009), and Study Progress Report (October 19, 2010).

On February 4, 2010, FERC issued a Final Study Plan Determination for the Conowingo Project. That determination required Exelon to conduct Biological and Engineering Studies of American Eel. The objectives of the study are to: 1) summarize available scientific and commercial information regarding the American eel; 2) identify suspected factors affecting American eel abundance; 3) describe the spatial distribution and size characteristics of American eels in the Conowingo tailrace; 4) examine the engineering feasibility and costs of upstream and downstream passage options, including consideration of potential fallback of eels after exiting an upstream passage device; (5) examine the potential impact of upstream and downstream passage of American eels on the Susquehanna River; (6) assess the cumulative impacts to the biodiversity the Susquehanna River ecosystem of upstream and downstream passage of American eel; and (7) if deemed beneficial to American eel abundance, identify potential locations for an upstream eel passage facility at Conowingo Dam.12

While FERC has asked Exelon to complete studies documenting eel presence below Conowingo Dam, it has not affirmatively required any modification of hydropower facility operation for better upstream or downstream passage, nor is that action a prospect that has been discussed in any stakeholder meeting in the past 2 years. In fact, FERC has not even required Exelon to adhere to the study report timetable concerning eels in any manner assuring adequate participation with stakeholders of the relicensing process. Likewise, the few reports Exelon has filed with FERC provide circumstantial, incomplete assessments solely concerning eel upstream migration, and then in a most abbreviated fashion. This particular relicensing scenario demonstrates the de facto policy of FERC in declining to exercise its authority to conserve remaining populations of American Eel.

6) The United States Environmental Protection Agency (EPA)

Pursuant to the federal Clean Water Act,13 the EPA has the legal authority to require the licensees of private hydroelectric dams to provide safe and efficient upstream and downstream passage for American Eels at hydroelectric facilities to allow these waters to meet their designated uses for fishing and habitat for aquatic species as required under the CWA. Further, the CWA provides the authority to regulate the disposition of ballast water. Thus far EPA has declined to exercise this legal authority to conserve remaining American Eels of the Atlantic seaboard.

12 Biological and Engineering Studies of American Eel at Conowingo Project, RSP 3.3, Conowingo Hydroelectric Project, FERC Project Number 405, February 2011. 13 16 U.S.C. § 797(e). 20

7) The Spread of A. Crassus is Due To Inadequate Regulation Of Ship Ballast Water Discharge

During the 2004 FWS sponsored workshop numerous panelists and authors pointed out that ballast water of ships is the most likely vector by which the rapid spread of this parasite occurs. This hypothesis is consistent with observations that busy deep water ports receiving empty ships, and therefore carrying ballast water, had some of the highest rates of parasitic infection, while such prevalence was either low or did not occur at some coastal locations with little or not shipping traffic (Morrison and Secor 2003; Rockwell et al. 2009). In infested areas, the frequency of infected eels, and the average number of A. crassus within their swim bladders, has been increasing (FWS Workshop 2004; Machut and Limburg 2008). A 2005 report by the Congressional Research Service (Buck 2005) documented extensively the inadequacy of regulations controlling invasive species transported in ballast water. The ongoing threat of parasites carried in ballast water of ships was not mentioned in the 2007 Final Determination to not list the American Eel.

8) Atlantic States Marine Fisheries Commission (ASMFC)

The Magnunson-Stevens Fisheries Conservation Act gives the ASFMC the legal authority to limit or prohibit the harvest of American Eel along the Atlantic seaboard of the United States. To date, ASFMC has declined to exercise such authority. On March 10, 2004 the American Eel Management Board of ASFMC issued a press release recommending the protection of American Eels under the ESA. That statement noted the worldwide decline of eel populations and American eel populations on the Atlantic coast in particular, as well as recommended that the FWS and NMFS consider the American Eel as a candidate for listing as a Distinct Population Segment under the ESA, as well as consider listing the entire coastwide stock under the ESA. ASFMC has not reduced or prohibited the ongoing harvest of all life stage so American Eel from waters of the Atlantic seaboard even with this statement.

E. Other Natural Or Manmade Factors Affecting Its Continued Existence

a. Anthropogenic Impacts on the American Eel

i. Upstream Passage at Dams

Female American Eels spend the majority of their lives in freshwater habitat along the Atlantic coast prior to returning to the Sargasso Sea to spawn. Safe and efficient access for juvenile eels to their freshwater habitat is essential to the survival of the American Eel. Coastal river systems along the Atlantic seaboard are the sole migratory pathways for female American eel to gain access to their required freshwater habitat.

ASFMC (2000) states:

By region, the potential habitat loss [for American Eel] is greatest (91 percent) in the North Atlantic region (Maine to Connecticut) where stream access is estimated to have been reduced from 111,482 kilometers to 10,349 kilometers of stream length. Stream habitat in the Mid Atlantic region (New York through 21 Virginia) is estimated to have been reduced from 199,312 km to 24,534 km of unobstructed stream length (88 percent loss). The stream habitat in the South Atlantic region (North Carolina to Florida) is estimated to have decreased from 246,001 km to 55,872 km of unobstructed stream access, a 77 percent loss.

The Maryland Department of Natural Resources, MBSS Newsletter March 1999, Volume 6, Number 1 states:

The most dramatic example of the decline of American Eel abundance is dam construction of the Susquehanna River. Prior to the completion of Conowingo and three other mainstem dams in the 1920s, eels were common throughout the Susquehanna basin and were popular with anglers. To estimate the number of eels lost as a result of construction of Conowingo Dam, we used MBSS data on American eels from the Lower Susquehanna River Basin and extrapolated it to the rest of the basin above the dam. Our best conservative guess is that there are on the order of 11 million fewer eels in the Susquehanna basin today than in the 1920s.

The magnitude of this loss is corroborated by the decline in the eel weir fishery in the Pennsylvania portion of the Susquehanna River. Before the mainstem dams were constructed, the annual harvest of eels in the river was nearly 1 million pounds. Since then, the annual harvest has been zero. Given the longevity of eels ins streams (up to 20 years or more) and their large size, the loss of this species from streams above Conowingo Dam represents a significant ecosystem-level impact.

ii. Downstream Passage at Dams

Female American Eels spend anywhere from 10 to 50 years in freshwater habitat along the Atlantic seaboard prior to returning to the Sargasso Sea to spawn and die. Safe and efficient access for maturing females from their freshwater habitat to the Atlantic Ocean is essential for continuance of the species. Coastal river systems along the Atlantic seaboard are the sole migratory pathways for female American Eels to gain access to their oceanic spawning grounds.

Records of severe kills of female American Eels by hydro facility turbines is pervasive. The corporate history of S.D. Warren Paper Company describes sever kills of female American Eels at the company’s dam at Ammoncongin Fall on the Presumpscot River, Maine during since the 1880s. “When warm weather came, the water would be full of eels and eels are fish with tough hides. The blades of the water wheels would not chew them up and there are frequent entries in the record stating the water supply has failed and the mill was down, because eels had stopped the wheels.” Hydroelectric dams located on the coastal watersheds of the Atlantic seaboard are a major source of mortality for female American Eels as they migrate from freshwater to the Sargasso Sea to spawn and die. Of 15,570 dams blocking American Eel habitat in the United States, Busch et al. (1998) reported that 1,100 of these dams are used for hydroelectric power. Few of those dams provide safe passage for migrating female American Eel. Thus, downstream passage by females at these dams occurs via the project turbines, which results in the death of a disturbingly large percentage of migrating eels. Recent studies of downstream female eel migration on the Shenandoah River showed roughly 47%

22 mortality, all via turbines.14 Indeed, this figure likely underestimates downstream mortality in relation to other locations because the Shenandoah’s dams utilize shut-off periods to facilitate downstream migration; yet even with those calculated downstream shut-off periods mortality was 47%!

ASFMC (2000) recognizes this serious issue in stating “[d]ownstream passage to the American eel’s historic habitat is just as important as successful upstream access. Therefore, turbine induced mortality during downstream passage needs to be resolved since it impacts prespawning adult silver eel.” Similarly, the FWS has documented large kills of migrating female American Eels at the Holyoke Dam, he lowermost hydroelectric facility on the Connecticut River.15

Without a doubt hydroelectric dam turbines inflict disproportionately large fatalities on downstream eel migrations. Mortality may be 50% or more for some types of turbines, with 80-100% being injured (Haro et al. 2003). This is of particular importance because the largest eels migrating downstream will be caught in turbines. Upstream passage past dams is difficult at best. Accordingly, few eels live upstream of dams, while those that do successfully migrate upstream of dams grow larger than those downstream. This is due to more competition for food and space downstream of dams. The larger eels upstream of dams are also disproportionately female. The larger the eel, the more fecund. Thus we are left with larger, more fecund females above dams that are more likely to be killed in downstream migrations by turbines and fail to spawn, and therefore those fatalities have a disproportionately negative effect on species recruitment.

iii. New Science Supports The Conclusion That The Effects Of Global Warming On Oceanic Conditions Have Contributed To The Decline Of The American Eel

Several authors and sources not previously considered by FWS in support of the 2007 Final Determination posit that changes in oceanic conditions are currently contributing to the dramatic decline of anguillid eels worldwide. (ICES 2006; IPCC 2007; Bonhommeau et al. 2008; Tsukamoto 2009). The primary means by which these changes are taking place include sea surface temperature changes that affect depth of the mixed layer which in turn disrupt the primary productivity in eel spawning areas, as well as changes in latitude of the 22.5 degree Celsius isotherm that affects the northern extent of eel spawning area and the transport and survival of leptocephali.

Some scientists reported changes in the sea surface temperature in the Sargasso Sea and its effect of European Eels. These changes included shifts in the winds in the northern Sargasso Sea, reducing southward Ekman transports and larval retention in the Sargasso Sea gyre. Such changes could also affect recruitment of the American Eel because of the proximity of its spawning area to the at of the European Eel in the southern Sargasso Sea, and similarities in the early migration pathways of both species out of the Sargasso Sea (Tsukamoto 2009). Likewise, increased temperature negatively affects cross-shelf transport of eels and the condition and size of eels upon their arrival at coasts (Wuenschel and Able 2008).

14 Welsh, Stuart A., David R. Smith, Sheila Eyler, Jennifer l. Zimmerman, Mary T. Mandt, “Migration of Silver-Phase and Yellow-Phase American Eels in Relation to Hydroelectric Dams on the Shenanhoah River, Phase I- Final Report (June 2009). 15 Novemeber 12, 2004 Petition from Timothy A. Watts and Dougless H. Watts, requesting that the FWS and NMFS list the American Eel as an endangered species under the Endangered Species Act. 23

Until recently scant attention has been paid to the influence of changing ocean conditions contributing to the decline of eels. Bonhommeau et al. (2008) analyzed the relationships between oceanic conditions in eel spawning areas and glass eel recruitment success of three species of Anguilla: A. Anguilla, A. rostrata, and A. japonica. Those reports state that since the 1970s global warming appears to have quickened the decline of these species due to regime changes that decreased primary productivity and thus eel recruitment.

Donner et al. (2005) conducted climate models based on historical temperature data and simulations for the 1870-2000 period and stated that “observed warming in the region is unlikely to be due to unforced climate variability alone.” Under different scenarios of future greenhouse gas emissions the authors show that temperature rise would affect coral and primary productivity of the mass coral bleaching in the Eastern Caribbean, and that these effects are expected even after stabilization of atmospheric carbon dioxide levels, thus complicating long term survival of the American Eel.

Worldwide decline in freshwater anguillid population recruitment began almost simultaneously in the 1980s. Among other factors studies show oceanic changes as the most likely factor driving this trend (Bonhommeau et al. 2008; Friendland et al. 2007). While the American Eel has experienced climate shifts previously and survived for millions of years, it has never faced the rapid, cumulative effects of anthropogenically- exacerbated environmental climate change (IPCC 2007), in combination with other anthropogenic environmental changes. These changes include: loss of habitat due to dams blocking migration, morbidity and mortality resulting from low stream pH (Jessop 2000; Velez-Espino and Koops 2009), mortality and injury in hydroelectric turbines when mature eels migrate downstream, commercial and recreational fishing harvests, contaminants ranging from mercury to PCBs (Ashley et al. 2007), and an invasive swim bladder nematode infestation (A. crassus) that disrupts swim bladder function and decreases eel resiliency during migration to spawning in the Sargasso Sea.

The American Eel’s resiliency and notable evolutionary history is inadequate to survive the cumulative effects of these simultaneous threats.

iv. Toxic Contaminants

ASFMC (2000) states:

American eel are benthic, long-lived and lipid rich. Therefore, American eel can accumulate high concentrations of contaminants, potentially causing an increased incidence of disease and reproductive impairments as is found in other fish species (Couillard et al. 1997). An analysis of the contaminants in migrating silver eel in the St. Lawrence River showed that the highest concentrations of chemicals were in the gonads. Concentrations of PCB and DDT were found to be 17 percent and 28 percent higher in the gonads than in the carcasses. The chemical levels in the eggs could exceed the thresholds for toxicity for larvae. Also, since the migrating females are not feeding, the chemical levels in the eggs could be even higher at hatching, increasing the likelihood of toxicity to the larvae (Hodson et al. 1994).

Due to Mercury, PCB and other contamination in the Susquehanna River, the

24 Pennsylvania Dept. of Environmental Protection in 2010 and 2011 issued a general, statewide fish consumption advisory. (PA Fish & Boat Commission 2010, 2011). The high number of coal-fired power plants in the Susquehanna River Basin in particular, and the Eastern seaboard generally, produce elevated levels of mercury in waterways. Mercury and other contaminants pose a threat to eels that must be taken into consideration.

III. Alternatively, Should American Eel Populations Along the Atlantic Seaboard Be Deemed Ineligible For Protection Under The ESA The Service Should List the Susquehanna River Basin American Eel As A Distinct Population Segment, Or List An Upper Atlantic Distinct Population Segment Including Mid- Atlantic and New England Populations

Distinct Vertebrate Population Segment (DPS)

Section 3(16) of the ESA defines “species” to include “any subspecies of fish or wildlife or plants, and any distinct population segment of any species of vertebrate fish or wildlife which interbreeds when mature” (16 U.S.C. 1532 (16)). Under the joint DPS policy of the Service and National Marine Fisheries Service (61 FR 4722; February 7, 1996), three elements are considered in the decision concerning the establishment and classification of a possible DPS. These are applied similarly for additions to or removal from the List of Endangered and Threatened Wildlife. These elements include:

(1) The discreteness of a population in relation to the remainder of the species to which it belongs; (2) The significance of the population segment to the species to which it belongs; and (3) The population segment's conservation status in relation to the Act's standards for listing, delisting, or reclassification (i.e., Is the population segment, when treated as if it were a species, endangered or threatened?).

Under the DPS Policy, a determination must first be made whether the population qualifies as a DPS; a finding that the population is both is required: (1) Discrete in relation to the remainder of the species to which it belongs; and (2) biologically and ecologically significant to the species to which it belongs. If the population meets the first two criteria under the DPS policy, then proceed to the third element in the process, which is to evaluate the population segment's conservation status in relation to the Act's standards for listing as an endangered or threatened species.

Discreteness

Under the DPS Policy, a population segment of a vertebrate taxon may be considered discrete if it satisfies either one of the following conditions:

(1) It is markedly separated from other populations of the same taxon as a consequence of physical, physiological, ecological, or behavioral factors. Quantitative measures of genetic or morphological discontinuity may provide evidence of this separation.

(2) It is delimited by international governmental boundaries within which differences in control of exploitation, management of habitat, conservation status, or regulatory

25 mechanisms exist that are significant in light of section 4(a)(1)(D) of the Act.

Markedly Separated From Other Populations of the Taxon

Under the first test of discreteness in DPS policy, a population segment may be considered discrete if it is “markedly separated from other populations of the same taxon as a consequence of physical, physiological, ecological, or behavioral factors. Quantitative measures of genetic or morphological discontinuity may provide evidence of this separation.'' Although absolute separation is not required under DPS Policy, the use of the term “markedly'' in the Policy indicates that the separation must be strikingly noticeable or conspicuous.

The important question with regard to discreteness under the DPS policy for the instant circumstance is whether or not the American Eel population of the Susquehanna River Basin is markedly separated from other populations of American Eel. The Susquehanna River Basin population could be found to be markedly physically separated if the distance between any part of that population and any other population is greater than the distance the eel is believed to be able to travel across areas without suitable habitat (i.e., non-aquatic landscape).

Available data shows that while American Eel are capable of brief overland travel the vast majority of their life is necessarily spent in aquatic environs. Indeed, all documented travel of American Eel occur in riverine, estuarine or marine environs. McGrath et al. (2003a) found that American eel in the upper portion of the St. Lawrence River migrated downstream from the end of June to the beginning of October, and that the primary migration in the lower estuarine portion of the river occurred in October. Slightly south, Winn et al. (1975) documented American eel migrating in Rhode Island from September through November. American Eel can survive out of water so long as their skin is moist, and this may contribute to their ability to surmount stream obstructions including dams and falls that block migration of other species (Bigelow and Schroeder 1953, Ross 1991).

The Susquehanna River Basin possesses hundreds of tributaries ranging from ephemeral streams to the main branch of the Susquehanna River. The Susquehanna River Basin is separated from the Delaware River Basin to the East, and the Ohio River Basin to the West, by virtue of distinct mountainous ranges with notable elevation gains for the Mid-Atlantic. These elevations thus create the respective watersheds noted above, or, in the words of John Wesley Powell, those “areas of land, a bounded hydrologic system, within which all living things are inextricably linked by their common water course.” This researcher failed to find any documented travel of American Eel through significant terrestrial landscapes lacking wetlands, small streams, springs, or like freshwater environs, and a distinct dearth of any such substantive overland travel that would be required to move between the Susquehanna Basin and Delaware or Ohio River Basins.

Similarly, a study of the main watercourses of the Susquehanna River Basin such as the West Branch of the Susquehanna failed to define any intervening habitat that could provide for regular movement of eel populations from basin to basin. Those main tributaries and their respective first and second order tributaries pose significant barriers to any regular eel movement. Firstly, due to the barriers to eel upstream migration from the Chesapeake arising from three hydroelectric facilities on the Lower 26 Susquehanna River. Secondly, eels confront the logistical issues of travel along the not inconsiderable length of tributaries while subject to predation, mortality and disease, and finally, eels face the logistical issue of surmounting watershed divides in the form of terrestrial elevation without discrete waterways to facilitate movement and maintain the necessary biological moisture critical to the American eel. Based on all of these factors, as well as data correlating the dramatic collapse of the Susquehanna River Basin eel fishery and population generally, we believe the remaining Susquehanna River Basin population of the American Eel can be classified as discrete under the DPS Policy by virtue of its physical separation from other populations.

Significance

If discreteness is satisfied, the next consideration is the population’s biological and ecological significance to the taxon to which it belongs in light of Congressional guidance that the authority to list DPSs be used “sparingly'' while encouraging the conservation of genetic diversity. To evaluate whether a discrete vertebrate population may be significant to the taxon to which it belongs, it is appropriate to consider available scientific evidence of the population segment's importance to the taxon to which it belongs. Because precise circumstances are likely to vary considerably from case to case, the DPS policy does not describe all the classes of information that might be used in determining the biological and ecological importance of a discrete population. However, the DPS policy describes four possible classes of information that provide evidence of a population segment's biological and ecological importance to the taxon to which it belongs.

As specified in the DPS policy (61 FR 4722), consideration of the population segment's significance may include, but is not limited to the following:

(1) Persistence of the discrete population segment in an ecological setting unusual or unique for the taxon, (2) Evidence that loss of the discrete population segment would result in a significant gap in the range of a taxon, (3) Evidence that the discrete population segment represents the only surviving natural occurrence of a taxon that may be more abundant elsewhere as an introduced population outside its historical range, or (4) Evidence that the discrete population segment differs markedly from other populations of the species in its genetic characteristics.

A population segment needs to satisfy only one of these criteria to be considered significant. Furthermore, the list of criteria is not exhaustive; other criteria may be used as appropriate. For the reasons noted below we believe that loss of American Eel populations of the Susquehanna River Basin, or alternately American Eel populations of the Upper Atlantic (Mid-Atlantic and New England historical ranges), would result in a significant gap in the range of the American Eel.

Evidence that Loss of the Discrete Population Segment Would Result in a Significant Gap in the Range of a Taxon

The Susquehanna River basin comprises 43% of the Chesapeake Bay watershed. Construction of Conowingo Dam in 1928 effectively closed the river to upstream

27 migration of elvers at river mile 10, those dams alone effectively ensuring the loss of at least 40% of the American Eel’s historic territory in the Chesapeake Bay. The loss of this portion of range represents a significant gap in the range of the taxon because the Susquehanna River Basin comprises 43% of the Chesapeake Bay watershed susceptible to American Eel habitation.

Studies on other dams in the U.S. and Canada have shown turbine mortality rates of the 3-foot female adult eels to be approximately 40 to 50%. If this is the base mortality rate for Conowingo, as well as Safe Harbor and Holtwood Dams upriver, the cumulative mortality rates for downstream silver eels equals 78 to 88%. If over decades – as this is the life span of freshwater American Eel - we combine these survival rates for females passing all three dams we arrive at a sad figure of approximately 12 to 22% survival. When taken in combination with the lack of any upstream passage for new generations of elvers science unambiguously shows the collapse of a distinct portion of the American Eel population in a territory encompassing the majority of Mid-Atlantic waterways.

Likewise, on the regional scale Mid-Atlantic states have experienced stream habitat reduction by 88 percent.16 Recent research by Richkus and Whalen (1999, 2000) has shown a decrease in yellow and silver eels in Ontario, Quebec, New York and Virginia. For example, during the 31-day peak migration period in 2004, the mean number of American eel passing through the Moses-Saunders Hydroelectric Dam at Cornwall, Ontario, decreased from previous estimates of over 27,000 individuals per day to 274 individuals per day (Casselman In press). By region, the potential habitat loss was greatest (91%) in the North Atlantic region (Maine to Connecticut) where stream access is estimated to have been reduced from 111,482 kilometers to 10,349 unobstructed kilometers of stream length. Stream habitat in the Mid Atlantic region (New York through Virginia) is estimated to have been reduced from 199,312 km to 24,534 km of unobstructed stream length (88% loss).17

In the assessment of the Atlantic Coast watersheds, the St. Lawrence River - Lake Ontario watershed was included. However, data were incomplete because only the United States’ side of the Lake Ontario basin was assessed. Construction of the Moses Saunders Dam (1954-58) impeded upstream and downstream migration on the St. Lawrence River, restricting access by migratory fish from the Atlantic Ocean to Lake Ontario and the Finger Lakes system. In 1974, an eel ladder was constructed, which probably reduced the effects of the lack of upstream passage at the Moses Saunders Dam. The number of American eel ascending the ladder has decreased dramatically in recent years. While a number of American eel have utilized the Saunders eel ladder, an assessment of the percent passed to the total number of eel in the system has not been conducted. It is unknown whether the number currently passed is sufficient to sustain the Saint Lawrence River/Lake Ontario stock. In the U.S. portion of the watershed, 455 dams result in 24,693 km of stream habitat lost or restricted from a total of 30,085 km (82% loss) to migratory fish originating in or having Lake Ontario as their destination. Since dams on the St. Lawrence River hinder fish movement through the St. Lawrence River to and from the Atlantic Ocean, the total kilometers of stream access lost or restricted in the Lake Ontario and St. Lawrence River watershed is actually much larger.

16 Atlantic States Marine Fisheries Commission Atlantic Coast Diadromous Fish Habitat: A Review of Utilization, Threats, Recommendations for Conservation, and Research Needs; Habitat Management Series #9 January 2009; Chapter 10. 17 ASMFC Interstate Fishery Management Plan for American Eel, 2000, p. 38. 28 The loss of the New England, and without a doubt the Susquehanna River Basin American Eel population, would represent a significant gap in the range of the species. The loss of 91% of the New England population’s habitat and 88% of the Mid-Atlantic’s habitat canot be taken as anything other than a significant gap in the range of the American Eel. Moreover, neither of these populations alone, nor the two combined as an Upper Atlantic, are peripheral populations. The magnitude of the loss of these upper ranges is further enhanced by the aforementioned data corroborating the importance of Northern, upstream female silver eels who live longer lives in freshwater habitat and who represent the most fecund – and thus most important to population recruitment – of the Atlantic populations of American Eel. Taken together, this data presents proof that the loss of the Susquehanna River Basin population alone represents a significant gap in the range of the taxon, while the loss of the Upper Atlantic population range in even a part of its totality (a trend corroborated by the best available science) indicates sufficient indicia confirming a significant gap in the range of the American Eel.

The American Eel population of the Susquehanna River Basin is both discrete and significant. Likewise, we believe the Upper Atlantic (Mid-Atlantic and New England) portion of the American Eel population is both discrete and significant. Further, both the Susquehanna River Basin population of the American Eel and the Upper Atlantic segment of the American Eel are likely to become endangered species within the foreseeable future throughout a significant portion of its range. For these reasons the Service should list optimally list an Upper Atlantic Distinct Population Segment of the American Eel as threatened under the ESA. Alternatively, for the reasons enunciated above the Service should create and list a Susquehanna River Basin Distinct Population Segment as threatened under the ESA.

IV. Conclusion

The American Eel is truly unique in that it spawns only once in its life in the Sargasso Sea. During its life the American Eel is harvested at nearly every life stage, and the eel suffers from the loss of nearly 90% of its historic range due to anthropogenic activity. The remaining habitat is severely degraded and still harbors numerous significant threats in the form of hydroelectric turbine mortality during downstream spawning migration. If the eel manages to survive all the aforementioned threats it is still subject to infection by the parasite A. crassus which can kill before it makes its way to the Sargasso Sea and is able to spawn.

Agencies with the authority to halt and mitigate eel mortality have universally not exercised those powers. Indeed, in the face of all the documented threats and specie decline the Service previously declined to protect the American Eel under the ESA. The new information presented in these comments, and the novel arguments presented, demonstrate the continued decline of this specie throughout a significant portion of its range and thus the American Eel, or alternatively one of the aforementioned Distinct Population Segments, merits listing as threatened under the ESA.

Respectfully submitted,

/s/ Michael Helfrich /s/ Guy Alsentzer Lower Susquehanna RIVERKEEPER® Director, Stewards of the Lower Susquehanna

29

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