Publications

Across the western United States, introductions of non-native fish into historically fishless mountain lakes have impacted native biota. Understanding the impacts of fish introductions is essential for conservation in Olympic National Park, a Biosphere Reserve. We reconstructed fish plantings using records dating back to 1930, followed by environmental DNA (eDNA) surveys to estimate the...

Increasing application of acoustic telemetry for determining survival, migration and habitat use of fishes highlights the need to improve interpretation of tracks that end abruptly: when is fishing mortality, predation, or some other cause to be inferred? Significant technological advances have led to the development of tags that “sense” predation and can be used to infer information...

Novel stressors like climate change and biological invasions alter ecological communities, resulting in changes to ecosystem services and biodiversity (that is, ecological transformation). Most ecological transformation research focuses on plants, but animals are likely affected by and plausibly mediate the extent, impact, and pace of transformations. In western North America, where...

Background Detailed studies of foraging behavior are needed for scientific management of the endangered rusty-patched bumblebee (Bombus affinis) in the disjunct and ecologically differentiated habitats it presently occupies. Current knowledge gaps hinder recovery planning but are challenging to redress through direct observation of rare interactions in the field.Methods We used genetic...

The long-term viability of the iconic Joshua tree of the Mojave Desert is being evaluated. In 2022, we measured the abundance and heights of Joshua tree stems on 62 1000 m2 plots in the eastern Mojave Desert of California. The 2022 plots were represented by 33 plots in a population of western Joshua trees (Yucca brevifolia) and 29 plots in a population of eastern Joshua trees (Y...

Warming winter temperatures are driving range expansion of tropical, cold-sensitive mangroves into temperate ecosystems. Along the Atlantic coast of North America, the mangrove range limit is particularly sensitive to climate variability and historical data demonstrate that the mangrove-salt marsh ecotone on this coast has shifted recurrently during recent centuries. However, a...

Species status assessments require an understanding of underlying population dynamics and important drivers of species demography. Large-scale assessments can be difficult due to challenges collating data obtained through different methods and different sources at multiple scales. Integrated population models (IPMs) provide a unified framework to combine multiple data sources and jointly...

The FluOil tool was developed to help with planning and early response for oil spills in rivers where subsurface oil-sediment interactions result in the formation of oil-particle aggregates (OPA). The turbulence and variable velocity associated with water flowing within a natural stream channel creates the conditions needed for an oil slick to break up into small droplets and mix in the...

Stormwater runoff in urban areas introduces numerous anthropogenic chemicals into surrounding aquatic environments. One such chemical is 6PPD (N-(1,3-Dimethylbutyl)-N’-phenyl-p-phenylenediamine), the primary antidegradant responsible for protecting tire rubber from ozone-induced degradation and cracking. When exposed to ozone on the road surface 6PPD is transformed into the toxic...

Extensive mortalities of adult coho salmon (Oncorhynchus kisutch), often called “Urban Runoff Mortality Syndrome” (URMS), have been documented during the fall in creeks where water quality has been degraded by roadway runoff. The primary cause of mortality is 6PPD-quinone (6PPDQ; N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine quinone)–an ozone transformation product that forms on all...

We examined ‘ōpe‘ape‘a, or Hawaiian hoary bat (Lasiurus semotus; Chiroptera: Vespertilionidae), acoustic activity and surveyed potential roost trees at the Ford Island Chief Petty Officer’s (CPO) Bungalows Neighborhood of Pearl Harbor National Memorial (PERL) on the island of O‘ahu. We established four acoustic monitoring stations (PERL1–PERL4) that operated nightly to survey for ‘ōpe...

The hydrology of the Upper Mississippi and Illinois Rivers is a fundamental driver of ecosystem patterns and processes across a large portion of the United States. Quantitative hydrologic data for the main stems of these rivers underlie numerous scientific investigations, statistical models, and decision-making processes for local, State, and Federal agencies involved in the Upper...