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Clubshell and Northern Riffleshell Mussels

Draft Environmental Assessment - May 2008

Augmentation and Reintroduction Plan for the Clubshell (Pleurobema clava) and Northern Riffleshell (Epioblasma torulosa rangiana) in Illinois


Below is the Purpose and Need section of the Assessment. Click here for the complete 31-page Assessment (1.7MB).


1. Purpose and Need

1.1. Purpose: The purpose of this Environmental Assessment (EA) is to consider alternatives for augmenting existing populations of the clubshell (Pleurobema clava) and/or reintroducing the northern riffleshell (Epioblasma torulosa rangiana) to waters within their historic range in Illinois. Both species are federally listed as endangered.


Preparation of this EA is in response to a request for federal assistance under section 6(d) of the Endangered Species Act of 1973, as amended (Act). The purpose of the augmentation and reintroduction is to implement a recognized recovery action for these two listed mussel species.


1.2. Need: The U.S. Fish and Wildlife Service’s (USFWS) recovery plan for the clubshell and northern riffleshell identified a recovery objective of establishing viable populations, including as many subpopulations as possible to maintain genetic variability, of each species in ten separate drainages in order to downlist each species from endangered to threatened. The recovery plan identifies the presence of the clubshell in nine drainages and the northern riffleshell in only seven drainages. Although the species may be present, not all occurrences represent viable, reproducing populations. In order to establish these species in at least ten drainages and maintain population viability, it is necessary to augment existing populations and reintroduce these species within their historic range.


1.3. Decisions To Be Made: The USFWS’s Regional Director, Great Lakes/Big Rivers Region, will select one alternative or a combination of the alternatives analyzed in detail and will determine, based on the facts and recommendations contained herein, whether this EA is adequate to support a Finding of No Significant Impact (FONSI) decision, or whether an Environmental Impact Statement (EIS) will need to be prepared.


1.4. Background: The clubshell and northern riffleshell were once widespread throughout the Ohio River and Maumee River drainages, and the clubshell appears to have been quite common. Both species were listed as endangered, pursuant to the Act, on 22 February 1993 (Department of the Interior 1993). Reasons for declines of both species include siltation from runoff, pollutants such as pesticides and fertilizers, habitat alteration from dams and impoundments, in-stream sand and gravel mining, and invasive species such as zebra and quagga mussels (USFWS 1994).


The clubshell historically occurred in the Ohio River watershed in New York, Pennsylvania, West Virginia, Ohio, Indiana, Illinois, Kentucky, Tennessee and Alabama. The clubshell also occurred in the Lake Erie watershed in the Maumee River drainage in Michigan, Indiana and Ohio. Extant populations of the clubshell are found in West Branch St. Joseph River in Ohio and Michigan; Fish Creek in Ohio and Indiana; Tippecanoe River in Indiana; Green River in Kentucky; Little Darby Creek in Ohio; Elk River in West Virginia; Hackers Creek in West Virginia; Pymatuning Creek in Ohio; and Allegheny River, French Creek, Conneaut Outlet, Conneauttee Creek and LeBoeuf Creek in Pennsylvania (USFWS 1994). In Illinois, the clubshell existed in Vermilion River, including the mainstem and North, Middle and Salt Forks. The clubshell was believed to be extirpated from this river system (Cummings et al. 1998); however, a live clubshell was recently found in the Middle Branch of North Fork Vermilion River (Szafoni et al. 2000).


The northern riffleshell historically occurred in many of the same Ohio River watersheds in Pennsylvania, West Virginia, Ohio, Indiana, Illinois, Kentucky, Tennessee and Alabama. The riffleshell also was found in the Lake Erie drainage in Ohio and Indiana, but the riffleshell’s range extended farther north into the Detroit and St. Clair River watersheds in Michigan and Ontario, Canada. Extant populations of the northern riffleshell are found in Fish Creek in Ohio and Indiana; Green River in Kentucky; Big Darby Creek in Ohio; Elk River in West Virginia; and Allegheny River, French Creek and LeBoeuf Creek in Pennsylvania (USFWS 1994). Although the riffleshell occurred in Michigan in Black and Detroit Rivers as recently as the 1980s, it is likely extirpated from those waterways due to channelization activities and zebra mussel infestations (Badra 2004). Metcalfe-Smith et al. (2003) recently confirmed the presence of the riffleshell in East Branch Sydenham River in Ontario. In Illinois, sub-fossil shells have been collected from North Fork and Vermilion Rivers; however, the riffleshell has not been reported alive in Illinois in more than 70 years (Cummings et al. 1998). Of the remaining populations in the Ohio River watershed, the only reproducing population is in French Creek (Allegheny River drainage) in Pennsylvania (Watters, personal communication, 2005).


The recovery plan for these two species identified eight Priority 1 Recovery Tasks. In the last fourteen years since publication of the recovery plan, several of these tasks have been accomplished, and many are ongoing. For example, the USFWS’s Ohio River Ecosystem Team identified priority streams for watershed protection/restoration to benefit mussel fauna. The population status of clubshell and northern riffleshell continues to be monitored at existing sites. Other ongoing recovery tasks include participation in the regulatory compliance processes and enforcement of laws and regulations pertaining to the collection of mussel specimens. Some studies into the mussels’ life histories have been conducted, such as identification of fish hosts for the clubshell and riffleshell (O’Dee and Watters 2000). To address the conservation needs of freshwater mussels, the National Native Mussel Conservation Committee published a “National Strategy for the Conservation of Native Freshwater Mussels” (1998). Among its recommendations, the Committee identified a goal of developing, evaluating and using the technology to propagate and reintroduce juvenile mussels on a large scale.


Above is the Purpose and Need section of the Assessment. Click here for the complete 31-page Environmental Assessment (1.7MB).





Last updated: September 21, 2016