The parthenogenetic all-female marbled crayfish is a novel research model and potent invader of freshwater ecosystems. It is a triploid descendant of the sexually reproducing slough crayfish, Procambarus fallax, but its taxonomic status has remained unsettled. By cross-breeding experiments and parentage analysis we show here that marbled crayfish and P. fallax are reproductively separated. Both...

Social behavior depends on sensory input from the visual, mechanical and olfactory systems. One important issue concerns the relative roles of each sensory modality in guiding behavior. The role of visual inputs has been examined by isolating visual stimuli from mechanical and chemosensory stimuli. In some studies (Bruski & Dunham, 1987: Delgado-Morales et al., 2004) visual inputs have been rem...

Abstract The future of the native European crayfish Austropotamobius pallipes depends on accurate conservation management. goal this paper is to attempt an investigation major ethical conflicts that can emerge in endangered threatened by invasive competitors, introduced diseases, and landscape alteration. To assess issue, we will employ Ethical Matrix, a version explicitly tailored for its use ...

-FO~ the incised, sand-bed streams of northcentral Mississippi, USA, fish predation is one plausible mechanism to explain both relatively low crayfish densities and differences in stream size occupied by various native crayfishes. I conducted two mesocosm experiments to test effects of a fish predator (channel catfish, Ictalurus punctahls) on the survival and size structure of native crayfishes...

The crayfish's lateral giant escape response, a relatively simple behavioral reaction, is readily modulated in certain situations. For example, when a crayfish is restrained, its lateral giant (LG) fibers--command neurons that mediate the escape response--are strongly inhibited (Krasne and Wine, 1975). Previous work (Glanzman and Krasne, 1983) had suggested that serotonin (5-HT) might mediate t...

Crayfish: Northern crayfish Orconectes virilis Louisiana crayfish Procambarus clarkii Water nymph crayfish Orconectes nais Rusty crayfish Orconectes rusticus Utah is inhabited by a single native crayfish known as the Pilose crayfish Pacifastacus (Hobbsastacus) gambelii. Its native range is in northern Utah’s Bear River, Weber River and Ogden River drainages and in the Raft River Mountain’s drai...

Submerged macrophytes enhance water transparency and aquatic biodiversity in shallow water ecosystems. Therefore, the return of submerged macrophytes is the target of many lake restoration projects. However, at present, north-western European aquatic ecosystems are increasingly invaded by omnivorous exotic crayfish. We hypothesize that invasive crayfish pose a novel constraint on the regenerati...

Crayfish are ecologically important in freshwater ecosystems, but few investigators have evaluated landscape patterns of their prevalence and abundance in temperate lakes. We report results of a crayfish survey for 100 lakes in the Puget Sound lowlands of Washington State (USA) serving as a census of the distributions of the signal crayfish Pacifastacus leniusculus and previously unknown popula...

The freshwater crayfish of the Aras Reservoir is an important economic fisheries resource of West Azarbaijan, Iran. This study was conducted to evaluate the prevalence of parasitic infestation of Crayfish seasonally in this area in 2010. Among 390 different sizes of Astacus leptodactylus which were examined,  a range of ectocommensals or ectosymbionts from a number of different phyla including ...