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Photo by Chris Lukhaup. Image may be subject to copyright.
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Cambarus longirostris Faxon, 1885

Longnose crayfish

Federal Protection: No US federal protection

State Protection: No Georgia state protection

Global Rank: G5Q

State Rank: S1

SWAP High Priority Species (SGCN): No

Element Occurrences (EOs) in Georgia: 4

Habitat Summary for element in Georgia: Riffle areas of streams under rocks


Description

The overall color of the Longnose Crayfish is light brown or olive to orangish-brown with no obvious markings. There are thin reddish bands at the rear of each abdominal segment. There is a single row of nearly indistinguishable tubercles along the mesial margin of the palm and there is gap between the fingers of the claws when the fingers are closed. There is a usually a tuft of hair-like setae at the base of the fixed finger of the claw. The areola is wide and the rostrum is fairly long and tapering with no marginal tubercles. The largest specimen reported from Georgia has a total body length of about 66 mm (2.6 in).

Similar Species

In most of the areas where Longnose Crayfish occurs, it is the only species whose claws show a large gap between the fingers when the fingers are closed. In tributaries to the Tennessee River in northwestern Georgia, it has been found with Tanback Crayfish (Cambarus girardianus) which also has the gaping claw characteristic. However, Tanback Crayfish has a striking pattern with a dark brown saddle behind the areola and a broad dark stripe down the center of the abdomen.

Habitat

The Longnose Crayfish is a stream dweller and is found beneath rocks in the fastest flowing areas of the streams it inhabits.

Diet

No studies of the Longnose Crayfish are known. Crayfishes are considered opportunistic omnivores and likely feed on live and decaying vegetation, aquatic insect larvae, small fishes, and dead animal matter.

Life History

Stream dwelling crayfishes typically hide during the day and come out at night to feed. Reproduction usually occurs during the spring and fall, but males in reproductive condition may be found at any time during the year. When female crayfish are ready to lay eggs, they usually find a secure hiding place and hence are rarely encountered. When the eggs are released, the female attaches them to her swimmerets and is said to be "in berry." Upon hatching, the juvenile crayfish are attached to the mother by a thread. After the juveniles molt for the second time, they are free of the mother, but stay close and will hold on to her for some time. Eventually they move off on their own. Crayfishes molt 6 or 7 times during their first year of life and most are probably able to reproduce by the end of that year. They molt once or twice a year for the remainder of their lives and live about 3 years. Males in reproductive condition have been collected in Georgia in April, October, and November. Three females carrying eggs were found in April and had between 42 and 53 eggs. The total length of the smallest breeding male from Georgia is about 42 mm (1.7 in) and the smallest female with eggs is 40 mm (1.6 in) in length (Hobbs 1981).

Survey Recommendations

Since this species is usually found in fast flowing water, it is most easily collected by holding a net perpendicular to the current downstream of a large rock, then lifting the rock and disturbing the substrate beneath it. If a crayfish is hiding underneath the rock, it will likely move into the net. Shocking downstream into a seine net with a backpack electroshocker or setting baited minnow traps overnight may also be effective.

Range

The Longnose Crayfish is found in the upper Tennessee River system in Georgia, North Carolina, Tennessee, and Virginia. In Georgia it is found in the Nottely River (Hiwassee River trib.), Lookout Creek (Tennessee River trib. in northwestern GA), and the headwaters of the Chattooga River (this may represent an introduction) (Hobbs 1981).

Threats

The small range of this species and the high development rates within that range are significant threats to the Longnose Crayfish. Residential growth can lead to an increase in stormwater runoff which may negatively alter water quality. Heavy sedimentation resulting from poor development and land management practices may cover substrates and other daytime hiding places on which crayfishes rely to avoid predation. The introduction of non-native crayfishes is a threat to all native crayfishes.

Georgia Conservation Status

Despite the narrow range of this species, it is thought to be stable in Georgia at this time. Much of the Georgia range is on US Forest Service property which is somewhat protected.

Conservation Management Recommendations

Conserving populations of the Longnose Crayfish will require general watershed level protection measures, including the protection of riparian zones, control of sediment and nutrient runoff from farms and construction sites, and limiting the amount of impervious cover (e.g., pavement) within occupied watersheds. Non-native crayfishes should never be used for bait; instead, anglers should use crayfishes collected from the river system where they will be fishing. Unused bait of any kind should not be released back into Georgia waters.

References

Hobbs, H.H., Jr. 1981. The crayfishes of Georgia. Smithsonian Contributions to Zoology 318:1–549.

Simmons, J.W. and S.J. Fraley. 2010. Distribution, status, and life-history observations of crayfishes in western North Carolina. Southeastern Naturalist 9 (Special Issue 3):79–126.

Taylor, C.A., G.A. Schuster, J.E. Cooper, R.J. DiStefano, A.G. Eversole, P. Hamr, H.H. Hobbs III, H.W. Robison, C.E. Skelton, and R.F. Thoma. 2007. A reassessment of the conservation status of crayfishes of the United States and Canada after 10+ years of increased awareness. Fisheries 32:372–389.

Authors of Account

Christopher E. Skelton

Date Compiled or Updated

C. Skelton, 2012: original account

C. Skelton, January 2019: general update of account.

6 October 2014. Photo by CE Williams. Image may be subject to copyright.