Publications

Blue Sucker Cycleptus elongatus is a state-listed threatened species in Texas and is considered vulnerable throughout its range. Once considered a single, wide-ranging species, blue suckers are now recognized as a complex of closely related, but genetically and morphologically distinct species within the genus Cycleptus, including an undescribed species within the Rio Grande Basin...

The five most common species of Pacific salmon, Rainbow Trout (steelhead) Oncorhynchus spp., and Atlantic Salmon Salmo salar intermingle in the North Pacific Ocean and its freshwater tributaries. Efficient morphological methods for distinguishing among these species are sometimes limited by condition of the specimen (degraded or missing morphology), life history stage, or training of the...

Although development and urbanization are typically believed to have negative impacts on carnivoran species, some species can successfully navigate an urban matrix. Sympatric carnivorans compete for limited resources in urban areas, likely with system-specific impacts to their distributions and activity patterns. We used automatically triggered wildlife cameras to assess the local...

Decades of fire suppression, logging, and overgrazing have led to increased densities of small diameter trees which have been associated with decreases in biodiversity, reduced habitat quality for wildlife species, degraded foraging conditions for ungulates, and more frequent and severe wildfires. In response, land managers are implementing forest restoration treatments using prescribed...

Accurate age estimates are critical for understanding life histories of fishes and developing management strategies for fish populations. However, validation of age estimates requires known-age fish, which are often lacking. We used known-age (ages 1–25) muskellunge (Esox masquinongy) to determine the precision and accuracy of age estimates from fin rays. We also determined whether fin...

Natural resource managers are increasingly faced with threats to managed ecosystems that are largely outside of their control. Examples include land development, climate change, invasive species, and emerging infectious diseases. All of these are characterized by large uncertainties in timing, magnitude, and effects on species. In many cases, the conservation of species will only be...

Aquatic organisms have adapted over evolutionary time-scales to hydrologic variability represented by the natural flow regime of rivers and streams in their unimpaired state. Rapid landscape change coupled with growing human demand for water have altered natural flow regimes of many rivers and streams on a global scale. Climate non-stationarity is expected to further intensify hydrologic

We evaluated relationships among hydrogeomorphology, vegetation structure and composition, and avian communities among three subreaches of the San Acacia Reach of the Middle Rio Grande (MRG) River of New Mexico. The subreaches varied in degradation, with Subreach 1 being severely entrenched and hydrologically disconnected, Subreach 2 being the least impacted, and Subreach 3 being...

Little is known about prey use by the orangebelly darter, Etheostoma radiosum, and what is known has been described from relatively large river systems. We examined prey use by orangebelly darters from first- and second-order tributaries in the Lower Mountain Fork River of southeastern Oklahoma. Adult darters (n = 141) were captured from five tributaries in 2015, and stomach contents...

Burbot (Lota lota: Gadidae) is a difficult species to manage effectively due to its preference for deep‐water habitats and under‐ice spawning behaviour, resulting in a poor understanding of its reproductive activity. However, the use of acoustic signalling by burbot as part of their mating system has recently been described and this behaviour may provide a means of investigating...

Geographic distributions are a basic component of a species’ ecology, and predicting distributions is a fundamental task of conservation and resource management. Reliable prediction depends on identification of appropriate scales of effect for environmental data, and scale-optimization techniques are thus desirable to identify optimal scales for predictor variables. Recent statistical...

Researchers and managers are often interested in monitoring the underlying state of a population (e.g., abundance), yet error in the observation process might mask underlying changes due to imperfect detection, availability for sampling, and heterogeneity in abundance. Additional heterogeneity can be introduced into a monitoring program when male-based surveys are used as an index for...