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Abstract: The presence of phenotypic behavioral correlations and their connection to fitness consequences of organisms have received considerable debate within the literature. Yet, little work has been carried out to connect any behavioral correlates found within a set of laboratory studies to natural behavior observed under complex environmental conditions. To help fill this gap, individual crayfish, collected from the same local population, completed five different behavioral assays in a laboratory setting in a random order. These data were used to reveal any possible correlations for behavioral scores across all of the laboratory tests. Subsequently, these same individuals were placed into the field and video recorded for 24 hr. A separate set of field behaviors, related to the laboratory assays, were quantified from the field videos. The normalized laboratory and field behaviors were used in three stepwise statistical analyses. First, normalized data were loaded into a PCA to generate a priori hypotheses on potential behavioral correlates. These hypotheses were subsequently tested using general multiple linear regression. Finally, structural equation modeling was performed to elucidate any behavioral modules from the laboratory assays that correlated with behavioral patterns present from the fieldwork. Three laboratory‐based behavioral modules were connected to three separate field assays: exploration–avoidance, bold–shy, and aggressiveness. Yet, some behaviors exhibited in the laboratory assays were uncorrelated with any behaviors found in the field and vice versa. Results from this study provide evidence that although many different behavioral correlates may exist within laboratory settings, these same modules may not translate directly into predicting behavior under natural settings. [ABSTRACT FROM AUTHOR]

Crayfish extract information from chemical stimuli during social interactions. Commercial fertilizers increase background ammonia concentrations which may interfere with chemical communication. Background pollution can disrupt perception of chemical stimuli in three ways: masking, sensory impairment, physiological impairment or in combination. We investigated whether exposure to ammonia alters agonistic behavior. Crayfish pairs exposed to 0.9 mg/L ammonia fought for a longer duration, while crayfish exposed to 9.0 mg/L ammonia fought for a shorter duration. Altering activity patterns of crayfish may alter crayfish populations leading to a nonproportional impact because of their importance to the structure and function of aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Morphological variation across environmental gradients can indicate an organismal phenotypic response to the surrounding environment. The interaction of body shape and water movement creates physical forces that can affect the ecology and evolution of benthic organisms in stream systems. Magnitude and frequency components of flow regimes have been linked to morphological variation in body shape of fish and macrophytes, but very few attempts have been made to evaluate similar relationships in stream insects. The aim of our study was to evaluate body-shape variation in large nymphs of an insect species and to test for a correlation with natural streamflow fluctuations in a regional geographic space. We sampled Acroneuria lycorias (Plecoptera: Perlidae) populations at 9 stream sites (8 systems) with an associated US Geological Survey stream gage. We calculated ecological flow statistics from daily discharge data, and we used 2-dimensional geometric morphometrics to describe variation in A. lycorias body shape. Multivariate analysis showed correlation of A. lycorias body shape with flow attributes. After correction for allometry, A. lycorias nymphs from streams with relatively high discharge and stable flow had an elongated streamlined body plan. Acroneuria lycorias nymphs from streams with relatively low discharge and flash flow had a short and wide (stout) body plan. Stream flows are under continuous natural and human-induced fluctuations, and our study provides information to help understand biological responses to hydrologic conditions. [ABSTRACT FROM AUTHOR]

Crayfish extract information from chemical stimuli during social interactions. Commercial fertilizers increase background ammonia concentrations which may interfere with chemical communication. Background pollution can disrupt perception of chemical stimuli in three ways: masking, sensory impairment, physiological impairment or in combination. We investigated whether exposure to ammonia alters agonistic behavior. Crayfish pairs exposed to 0.9 mg/L ammonia fought for a longer duration, while crayfish exposed to 9.0 mg/L ammonia fought for a shorter duration. Altering activity patterns of crayfish may alter crayfish populations leading to a nonproportional impact because of their importance to the structure and function of aquatic ecosystems.