Description
Synonymy- The listed names were selected from 13 synonyms listed by Hobbs and Jass (1988). Describers for the genus and species names are: Cambarus virilis; Orconectes virilis Penn 1950. Hagen 1871. There have been numerous misidentifications as F. rusticus (Bundy 1882; Faxon 1884; 1885; Underwood 1886; Harris 1903; Faxon 1914; Creaser 1932; Walters 1939). Genetic analysis indicates that 'F. virilis' is a complex consisting of several cryptic species and lineages, including previously described and synonymized species F. nais (Okalahoma) and F. quinebaugensis (Massachusetts). Specimens from Europe F . cf. virilis Europe represent a distinct clade of unknown North American origin (Filipova et al. 2009).
Potentially Misidentified Species - Faxonius rusticus (Rusty Crayfish) has been present in the PA Susquehanna drainage since the 1970s (Hobbs and Jass 1988) and has recently been reported in MD Potomac and Susquehanna tributaries (USGS Nonindigenous Aquatic Species Database 2007-2019; Kilian 2010).
Taxonomy
| Kingdom | Phylum | Class | Order | Family | Genus |
|---|---|---|---|---|---|
| Animalia | Crustacea | Malacostraca | Decapoda | Cambaridae | Faxonius |
Synonyms
Invasion History
Chesapeake Bay Status
| First Record | Population | Range | Introduction | Residency | Source Region | Native Region | Vectors |
|---|---|---|---|---|---|---|---|
| 1957 | Established | Expanding | Introduced | Regular Resident | North America | North America | Fisheries(Discarded Bait) |
History of Spread
Faxonius virilis (Virile Crayfish) is native to the Great Lakes, southern Arctic, and northern Mississippi drainages from northern AR, MS, and TN to Alberta-southeastern Quebec, with populations extending west in the Mississippi drainage to MT and CO (Hobbs 1989). Crocker (1979) considered its range through most of New England as being largely native, but Hobbs (1989) and Taylor et al. (1996) consider it at least partly introduced in this region. Faxonius virilis is probably introduced in the Hudson River valley (Smith 1979; Mills et al. 1997). Faxonius virilis was listed as being introduced in 6 states (with 8 more questionable) (Hobbs 1989), and in 16 states by Taylor et al. (1996). Among states with definite introductions are CA, AZ, PA, NJ, MD, VA, WV, and the District of Columbia (Hobbs 1989; Taylor et al. 1996). More recently, it has been collected in Piedmont areas of NC (Cooper et al. 1998) and eastern New Brunswick (McAlpine et al. 2007). F. virilis has also been introduced into Mexico and unsuccessfully into France and Sweden (Hobbs et al. 1989; Lowery and Holdich 1989). In 2004, it was discovered in ponds leading to the Lee River, North London, England (Ahern et al. 2008) and the Netherlands (Filipova et al. 2004) and is established and spreading in both countries.
Schwartz et al. (1963) have suggested that F. virilis was introduced into the Chesapeake and other Atlantic drainages as a result of shipments to Eastern markets from the Midwest (Faxon 1885), when crayfish were highly esteemed as food. However, its rapid spread since its first recorded collection in the 1950's suggest that its introduction into the Chesapeake drainage may have occurred later. Meredith and Schwartz (1960) suggested an introduction with discarded bait. Its rapid spread between Chesapeake river drainages is strongly suggestive of bait bucket transfers, but some natural dispersal among Upper Bay tributaries is likely (Norden, 1996; Kilian et al. 2010).
James River - In 1988-89, F. virilis was abundant in the Ridge and Valley (Mountain) region of the James at Eagle Rock (Botecourt County) VA (Mitchell and Smock 1991), but was not found at a Fall-Line site near Richmond. Occurrence in the James is not indicated by the range map given by Hobbs and Jass (1988). Although Mitchell and Smock do not discuss introduced status of F. virilis in the James, based on its history elsewhere, it is likely to spread downstream toward tidal waters.
Potomac River - In 1976, F. virilis was collected and apparently was abundant at Great Falls VA (Hamilton 1979). In 1977, it was collected in Broad Run, Loudon County VA, on the Piedmont, and in 1983 in Frederick County (Ridge and Valley Province) VA (United States National Museum of Natural History collections). It was found in WV Potomac tributaries (Jefferson and Berkeley Counties) in 1989 and has apparently replaced F. limosus there (Jezerinac et al. 1995). It was listed for Washington DC by Hobbs (1989), and so probably occurs in the Potomac estuary, although it was not found in MD Potomac tributaries close to tidal waters in recent (1989-2007) surveys. Faxonius virilis is widespread in Piedmont tributaries of the Potomac ((Maryland Biological Stream Survey, Maryland Department of Natural Resources, 1989-2007, Kilian et al. 2010)
Patuxent River - By 1976, F. virilis was present in upper Patuxent (Lee 1976), although it had not been found in the Patuxent drainage by Meredith and Schwartz (1960). It now occurs throughout the freshwater Patuxent (Norden 1995). Kilian et al. (2010) note one occurrence near the head of tide of the Patuxent, but many in the Fall Line and Piedmont regions of the river.
Upper Bay drainages - In 1957, Faxonius virilis was first collected in the Patapsco River, Patapsco State Forest MD (=Patapsco Valley State Park), Howard County (United States National Museum of Natural History collections). By 1960 it was found at 5 sites in the Patapsco drainage (Meredith and Schwartz 1960), and by 1961, it was found throughout the drainage, including tidal waters below Elkridge (Schwartz et al. 1963). By 1966, it was found in the drainage of the Gunpowder River above Prettyboy Dam, but not below the dam at that time. It was also found in a temporary pond 1.5 miles from Curtis Creek near Baltimore Harbour, suggesting that dispersal had occurred through the Bay (Odell and Grimm 1966). In recent surveys (1989-2007), it was widespread in the Patuxent, Gunpowder, and Bush river systems (Killian et al. 2010).
Eastern Shore - Faxonius virilis occurs in the tributaries of the upper Delmarva Peninsula, but the extent of its range is not known (Norden 1995) It was not reported in eastern shore tributaries by Kilian et al. (2010).
History References - Cooper et al. 1998; Crocker 1979; Faxon 1885; Hamilton 1979; Hobbs 1989; Hobbs and Jass 1988; Hobbs et al. 1989; Jezerinac et al. 1995; Lee 1976; Lowery and Holdich 1989; Meredith and Schwartz 1960; Mills et al. 1997; Odell and Grimm 1966; Norden 1995 personal communication; Schwartz et al. 1963; Smith 1979; Taylor et al. 1996; United States National Museum of Natural History collections
Invasion Comments
Ecology
Environmental Tolerances
| For Survival | For Reproduction | |||
|---|---|---|---|---|
| Minimum | Maximum | Minimum | Maximum | |
| Temperature (ºC) | 0.0 | 39.0 | 10.0 | |
| Salinity (‰) | 0.0 | 14.0 | 0.0 | |
| Oxygen | hypoxic | |||
| pH | 5.0000000000 | 9.5000000000 | ||
| Salinity Range | fresh-oligo |
Age and Growth
| Male | Female | |
|---|---|---|
| Minimum Adult Size (mm) | 26.0 | 27.0 |
| Typical Adult Size (mm) | 34.5 | 33.6 |
| Maximum Adult Size (mm) | 59.0 | 60.0 |
| Maximum Longevity (yrs) | 3.0 | 3.0 |
| Typical Longevity (yrs | 1.5 | 1.5 |
Reproduction
| Start | Peak | End | |
|---|---|---|---|
| Reproductive Season | |||
| Typical Number of Young Per Reproductive Event |
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| Sexuality Mode(s) | |||
| Mode(s) of Asexual Reproduction |
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| Fertilization Type(s) | |||
| More than One Reproduction Event per Year |
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| Reproductive Startegy | |||
| Egg/Seed Form |
Impacts
Economic Impacts in Chesapeake Bay
Faxonius virilis(Virile Crayfish) is commonly used for bait, but it is too small for human consumption. Since it replaced a native species with similar habits, its effects on fisheries are hard to determine.
Economic Impacts Outside of Chesapeake Bay
'In North America, crayfish of the genus Faxonius have, at present, only minor economic importance. They are harvested for biological supply houses to be sold for research and teaching purposes. Only a small quantity is sold for human consumption, mainly in the state of Wisconsin' (Momot 1989).
References- Momot 1989
Ecological Impacts on Chesapeake Native Species
Faxonius virilis (Virile Crayfish) are now apparently widespread in the Chesapeake bay watershed, but little current information is available on their current distribution or impacts on native biota in the estuary.
Competition- The spread of Faxonius virilis was accompanied by the displacement of Faxonius limosus (Spinycheek Crayfish, Coastal Plains River Crayfish) and Cambarus bartonii (Appalachian Brook Crayfish) in the Patapsco and other rivers (Schwartz et al. 1963). Its displacement of these species is believed to be due to wider environmental tolerances, larger size, and more aggressive behavior (Bovberg 1970; Odell and Grimm 1966; Schwartz et al. 1963). Faxonius limosus is now probably imperiled in Maryland (but not yet officially listed) (Norden 1995 personal communication), and has been suggested as a Federal endangered species, largely because of its displacement by F. virilis and F. rusticus (Rusty Crayfish) in much of its range (Jezerinac et al. 1995). In the late 1950s, F. limosus was found in 62% of Piedmont MD stream locations surveyed, while F virilis was found in 8% (Meredith and Schwartz 1960). In 1989-2007, F. limosus had decreased to 11% of locations, while F. virilis was found in 46% of the locations sampled. The two species co-occurred in only 1% of locations (Kilian et al. 2010). This species has apparently been extirpated from the Potomac drainages of WV (Swecker et al. 2010).
Differences in feeding behavior between F. virilis and native species, including C. bartoni, F. limosus, and others, have not been studied, so it's not clear that the F. virilis invasion has resulted in changes in predation, herbivory, etc. for Chesapeake Bay biota.
References - Bovberg 1970; Jezerinac et al. 1995; Norden 1995 personal communication; Odell and Grimm 1966; Schwartz et al. 1963;
Ecological Impacts on Other Chesapeake Non-Native Species
Faxonius virilis (Virile Crayfish) are now apparently widespread in the Chesapeake bay watershed, but little current information is available on their current distribution or impacts on introduced biota,
Predation - An introduced snail Bithynia tentaculata (Faucet Snail, mud Bithynia), found in the Potomac, is one of the more vulnerable species to crayfish predation. However, rates and species preferences for predation did not differ between the native F. limosus (Spinycheek Crayfish) and F. virilis (Hamilton 1979).
References- Hamilton 1979