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An observed predation of a federally endangered Percina rex (Roanoke Logperch), by an invasive Faxonius ozarkae (Ozark Crayfish), is detailed herein. We observed the predation on 11 August 2021 in the Roanoke River near downtown Roanoke, Roanoke County, VA. The crayfish had recently captured a sub-adult Roanoke Logperch and was dragging it under a cluster of cobbles. Upon observing this behavior, we retrieved the fish, positively identified it, and confirmed it as dead. The initial state of the Roanoke Logperch was nearly undamaged apart from indentations from the crayfish's chelae behind the operculum and near the caudal peduncle. Coloration of the Roanoke Logperch at time of observation indicated the fish had likely recently been captured. A camera was not readily available, so we returned the fish to the cobble cluster until a photograph could be captured. Upon returning approximately one-half hour later, coloration of the fish had begun to fade, and the ventral portion of the fish was partially consumed by the crayfish. Herein we discuss the significance of this observation and the gravity of the continued expansion for this invasive crayfish species, both within the confines of Virginia's waters as well as throughout the eastern United States.. [ABSTRACT FROM AUTHOR]

Data of the life history of Cambarus (Puncticambarus) theepiensis Loughman, Foltz, Garrison and Welsh, 2013 was collected monthly from May 2012 through April 2013 from two sites within the Twelve pole Creek watershed in southwestern West Virginia, USA. Mature females showed signs of glair development in early May. Egg extrusion was noted in early June, with first- through third-stage juveniles occurring from July to August, before becoming free-living juveniles in late August and September. Evidence for possible overwintering with young was found as a mature female with free-living juveniles was collected in early April. Mature female total carapace length (TCL) ranged from 29.7-52.4 mm. Support for the hypothesis that form change occurs in female cambarid crayfishes was found in female C. theepiensis. Form I males were collected throughout the year, but reached their highest densities in May through August. Size cohorts, determined through histograms, demonstrate six size cohorts existed between both streams, following appearance of young of the year (YOY) in late summer. Cambarus theepiensis appears to have life history characteristics similar to other Cambarus species, displaying K-selected life history traits. [ABSTRACT FROM AUTHOR]

A new method (baited lines) is described for the collection of burrowing crayfishes, where fishing hooks baited with earthworms and tied to monofilament leaders are used to lure crayfishes from their burrow entrances. We estimated capture rates using baited lines at four locations across West Virginia for a total of four crayfish taxa; the taxa studied were orange, blue, and blue/orange morphs of Cambarus dubius (Upland Burrowing Catfish), and C. thomai (Little Brown Mudbug). Baited-line capture rates were lowest for C. thomai (81%; n = 21 attempts) and highest for the orange morph of C. dubius (99%; n = 13 attempts). The pooled capture rate across all taxa was 91.5% (n = 50 attempts). Baited lines represent an environmentally nondestructive method to capture burrowing crayfishes without harm to individuals, and without disturbing burrows or the surrounding area. This novel method allows for repeat captures and long-term studies, providing a useful sampling method for ecological studies of burrowing crayfishes. [ABSTRACT FROM AUTHOR]

North America is home to some of the most diverse freshwater mussel fauna (Mollusca: Unionidae) in the world, with the majority of mussel diversity located in the southeastern United States. Unfortunately, mussels are one of most imperiled groups in the world and species are declining across the United States. Anthropogenic habitats may function as refugia for some mussel species; however, many of these habitats are ignored during studies. The False River of Louisiana is a unique system that has separated from the Mississippi River and is dependent on an artificial canal system to maintain water levels. The canal may act as refugia for mussels during climatic events, but it is unknown whether the system can sustain mussels. To obtain an understanding of the structure and health of mussels within this anthropogenic structure, we surveyed mussels and fish at 11 sites in a section of artificial canal connected to the False River. We analyzed the mussel assemblage with regard to life history strategies and compared fish presence to known fish host use of our various mussel species. We collected 388 individuals of 13 live mussel species, with 5 additional species located as shell material. The fish assemblage consisted of 22 species of which 15 were hosts for at least one member of the mussel assemblage. The mussel assemblage primarily consisted of opportunistic species and host generalists with a few dominant species. This is, to our knowledge, the first mussel peer-reviewed mussel data reported from any portion of the False River system and the mussel assemblage appears to follow predictable trends for flashy systems noted in other rivers. Our study highlights that the False River canal system is capable of sustaining mussels and indicates that anthropogenic structures should be incorporated into future survey efforts. [ABSTRACT FROM AUTHOR]