endemic to a single nation

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: (>2,500,000 square km (greater than 1,000,000 square miles)) Ranges along the Atlantic watersheds from Maine to Virginia. Although introduced to New Brunswick and parts of Quebec, some occurrences in Quebec are likely the result of an extension of its natural range along the Champlain and Memphremagog Lakes (Dube and Desroches, 2007). It as been introduced into western Europe (Hobbs 1989). Although first introduced into Europe in 1890 (Germany), secondary introductions have occurred throughout continental Europe in over 20 countries (not yet in the Iberian Peninsula) making it one of the most common crayfish there (Petrusek et al., 2006; Parvulescu et al., 2009; Holdich and Black, 2007; Baitchorov and Giginiak, 2009; Puky, 2009).

• Freshwater

Habitat Type: Freshwater

Comments: Prefers shallow bay areas of larger lakes (Hogger, 1988). It also inhabits clear streams that are 10100 m wide, with silt, cobble, gravel and sand substrates (Jezerinac 1995; Aiken 1965). This species has also been found in lakes (Aiken 1965). Individuals are often found in shallow depressions in pools and have rarely been captured where silt is absent from the substrate (Jezerinac 1995).

Non-Migrant: No. All populations of this species make significant seasonal migrations.

Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: No. No populations of this species make annual migrations of over 200 km.

Note: For many non-migratory species, occurrences are roughly equivalent to populations.

Estimated Number of Occurrences: > 300

Comments: In New Jersey, Francois (1959) cites it for Bergen, Burlington, Camden, Gloucester, hunterdon, Mercer, Monmouth, Morris, Passaic, Sussex, Sommerset, and Warren Cos.; as well as Philadelphia and Bucks Cos., Pennsylvania. Horowitz and Flinders (2004) found it to be uncommon (2 of 15 stations) in the Piedmont, Ridge and Valley and Highlands regions of New Jersey. It was recently documented in the vicinity of Plummers Island (bank of Potomac River), Montgomery Co., Maryland (Norden, 2008). In Maryland, it was historically the most abundant species but is currently present, but uncommon, in the Appalachian Plateau in tributaries to the North Branch Potomac River (possibly via dispersal through the low-gradient Chesapeake and Ohio Canal) and so is now uncommon west of the Piedmont, somewhat common but declining within the Piedmont (except where non-native crayfish species are absent), and common in the Coastal Plain (Killian et al., 2010). In New York's Hudson River drainage, Smith (1979) added Rennselaer Co. In southern New England, Smith (1981) documented it in the Pawcatuck (CT/RI), Thames (CT), Connecticut (MA/CT), and Housatonic (CT) River systems. Although there is question as to whether New England occurrences are native, Faxon (1914) cites occurrences in Massachusetts. Smith (2000) notes that in southern New England, native populations (if, indeed native) are confined to major south flowing river systems including the Housatonic River, Connecticut River (where it is common), and Thames River drainages; with less frequently encountered populations east of these drainages (probably introduced) and scattered populations known from the Merrimack River, Charles River, Narragansett Bay, Mount Hope Bay, and other coastal drainages (not the Hudson River drainage). Although introduced to New Brunswick and parts of Quebec, some occurrences in Quebec are likely the result of an extension of its natural range along the Champlain and Memphremagog Lakes (Dube and Desroches, 2007).

>1,000,000 individuals

Comments: This species is known to be abundant in sites of suitable habitat.

Canada

Rounded National Status Rank: N4 - Apparently Secure

United States

Rounded National Status Rank: N5 - Secure

Rounded Global Status Rank: G5 - Secure

Reasons: This species is widespread and common along North American Atlantic drainages but has been introduced widely to the rest of North America and across western Europe.

Intrinsic Vulnerability: Not intrinsically vulnerable

Environmental Specificity: Broad. Generalist or community with all key requirements common.

Global Short Term Trend: Increase of 10 to >25%

Comments: Although first introduced into Europe in 1890 (Germany), secondary introductions have occurred throughout continental Europe in over 20 countries (not yet in the Iberian Peninsula) making it one of the most common crayfish there (Parvulescu et al., 2009; Holdich and Black, 2007; Baitchorov and Giginiak, 2009; Puky, 2009). It is declining in Maryland within and west of the Piedmont at the expense of increased range expansion of Orconectes virilis (Kilian et al., 2010) and similar trends have been observed in southeastern Pennsylvania (Bouchard et al., 2007) and West Virginia (Jezerinac et al., 1995) where it is now believed extirpated (Swecker et al., 2010).

Global Long Term Trend: Increase of >25%

Comments: There are no known major threats to this species. Hybridization is known to have occurred between Orconectes limosus and Orconectes rusticus at a single locality in Massachusetts. The cause of this hybridization are not known, however, transplanting of species to new habitats or the inability to find conspecific mates due to habitat alteration are both possible (Smith, 1981). It is declining in Maryland within and west of the Piedmont at the expense of increased range expansion of Orconectes virilis (Kilian et al., 2010) and similar trends have been observed in southeastern Pennsylvania (Bouchard et al., 2007) and West Virginia (Jezerinac et al., 1995) where it is now believed extirpated (Swecker et al., 2010). However, this is not having a major impact on the global population of this species.

Global Protection: Unknown whether any occurrences are appropriately protected and managed