Aquatic

The Herpetological Research Team is using acoustic surveys and eDNA methods to evaluate the progress of invasive bullfrog removal and Oregon spotted frog recovery.

The Herpetological Research Team is recording audio in areas where American bullfrogs have invaded to learn more about where and when they are breeding and inform managers tasked with controlling their spread.

The Herpetological Research Team at the USGS Forest and Rangeland Ecosystem Science Center uses innovative tools to investigate the invasion and spread of American bullfrogs in Washington and Oregon and understand how bullfrogs are interacting with native amphibians.

The Issue: Streamflow permanence refers to the probability that a stream will lose surface flow (become a dry channel), as well as the timing, duration, and frequency of drying. Patterns of streamflow permanence drive important decisions regarding forest management and other land uses. The Colville National Forest Land and Resource Management Plan (2019), for example, specifies riparian management...

USGS researchers are working with the Monterey Bay Aquarium Research Institute to optimize autonomous, robotic samplers for detection of DNA fragments shed by biological threats (BT; invasive species, parasites, pathogens) in our nation’s waters. Finding DNA fragments (a method known as environmental DNA sampling) produced by an emerging BT in water is akin to finding a needle in a haystack—many...

Whether generalists or specialists, wildlife species use habitats based on their structural, compositional, and climatic characteristics. This use may vary with life stage, age, or physiological condition of the animal, as well as weather, season, food availability, need for cover or shelter, and other factors. Our research focuses on understanding the intrinsic and extrinsic factors that drive...

Increases in summer stream temperature as a result of human impacts and climate change may exceed the thermal tolerances of aquatic biota that are adapted to colder environments and climates. The combined effects of humans and climate change are of global concern across the range of coldwater aquatic organisms.

Water resources, riparian areas, and aquatic organisms are of critical importance in natural resource management. Yet, they are difficult to map, monitor, and understand in a spatially explicit and extensive manner as can be done more easily in terrestrial environments.

Restoration of aquatic ecosystems involves a broad spectrum of active and passive efforts. Passive efforts rely on natural recovery of ecosystems, such as land use practices that protect riparian zones and sources of wood and sediment that drive the geomorphic and associated biological functions in streams. Active efforts involve more direct intervention, usually applied to specific locations, to...

The Oregon spotted frog (Rana pretiosa) is a medium-sized anuran native to the northwestern United States. Body coloration ranges from brown or tan to brick red, usually overlaid with dark, ragged spots. Oregon spotted frogs can be distinguished from other native species by their relatively short hind legs, orange or red wash of color on underside of abdomen and legs, and upturned chartreuse eyes...

Mercury contamination is a serious issue that impacts both ecosystem and human health on a global scale. In its organic (methylmercury) form, mercury is highly bioaccumulative and is among the most toxic compounds commonly found in the environment. Mercury is a relatively distinctive contaminant in the sense that the risk of deleterious environmental effects is more strongly related to ecological...

The Pacific Northwest includes a patchwork of public lands managed by numerous state and federal agencies. Our research informs and supports these agencies as they conserve and manage native amphibian species, including pre- and post-treatment assessment, decision support, long-term monitoring, population translocation, and habitat restoration.