Publications

modeling predicts that redd trampling by cattle may contribute to population declines of native trout.	unrestricted livestock grazing can degrade aquatic ecosystems, and its effects on native vertebrate species are generally mediated by changes to physical habitat. recently, high estimated rates of cattle trampling on artificial redds within federal grazing allotments in southwestern montana, usa, has raised concern that direct mortality from trampling may contribute to imperilment of native westslope cutthroat trout (oncorhynchus clarkii lewisi). to explore the implications of cattle trampling, ...	2010	20597282
assessing time-integrated dissolved concentrations and predicting toxicity of metals during diel cycling in streams.	evaluating water quality and the health of aquatic organisms is challenging in systems with systematic diel (24 h) or less predictable runoff-induced changes in water composition. to advance our understanding of how to evaluate environmental health in these dynamic systems, field studies of diel cycling were conducted in two streams (silver bow creek and high ore creek) affected by historical mining activities in southwestern montana. a combination of sampling and modeling tools was used to asse ...	2012	22481055
long-term effects of a trophic cascade in a large lake ecosystem.	introductions or invasions of nonnative organisms can mediate major changes in the trophic structure of aquatic ecosystems. here we document multitrophic level impacts in a spatially extensive system that played out over more than a century. positive interactions among exotic vertebrate and invertebrate predators caused a substantial and abrupt shift in community composition resulting in a trophic cascade that extended to primary producers and to a nonaquatic species, the bald eagle. the opossum ...	2011	21199944
concentrations of metals in water, sediment, biofilm, benthic macroinvertebrates, and fish in the boulder river watershed, montana, and the role of colloids in metal uptake.	to characterize the partitioning of metals in a stream ecosystem, concentrations of trace metals including as, cd, cu, pb, and zn were measured in water, colloids, sediment, biofilm (also referred to as aufwuchs), macroinvertebrates, and fish collected from the boulder river watershed, montana. median concentrations of cd, cu, and zn in water throughout the watershed exceeded the u.s. epa acute and chronic criteria for protection of aquatic life. concentrations of as, cd, cu, pb, and zn in sedim ...	2007	17219028