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Cooperative Research Units

Established in 1935 at Iowa State University, our mission is our hallmark: to work with University students to develop the conservation workforce, help decision-makers make complex conservation decisions, and provide technical assistance between natural resource agencies and universities. We support 43 units located in 41 States, at 44 host universities. Our Program Office is in Reston, Virginia.

Our website is currently undergoing a major update. Be sure to visit regularly for the latest enhancements.

News

Tight Lines: Evaluating Rainbow Trout Fishing in Oklahoma

Tight Lines: Evaluating Rainbow Trout Fishing in Oklahoma

Trees Act Their Size, Not Their Age

Trees Act Their Size, Not Their Age

Fishing in Nervous Waters: Using Science to Address Uncertainty in Steelhead Fisheries

Fishing in Nervous Waters: Using Science to Address Uncertainty in Steelhead Fisheries

Publications

Plasticity in the reproductive biology of Yellowstone cutthroat trout Oncorhynchus virginalis bouvieri in Yellowstone Lake following lake trout Salvelinus namaycush invasion Plasticity in the reproductive biology of Yellowstone cutthroat trout Oncorhynchus virginalis bouvieri in Yellowstone Lake following lake trout Salvelinus namaycush invasion

Yellowstone cutthroat trout Oncorhynchus virginalis bouvieri in Yellowstone Lake are the focus of intensive conservation efforts due to the threat of predation by invasive lake trout Salvelinus namaycush. Suppression gillnetting has reduced the abundance of predatory lake trout, and the Yellowstone cutthroat trout population is recovering. Long-term monitoring indicates the size...
Authors
Michelle A. Briggs, Molly A. Webb, Christopher S. Guy, Todd M. Koel

Igniting the transition from water quality to biological condition and ecological health Igniting the transition from water quality to biological condition and ecological health

Karr (1981), which introduced the index of biotic (or biological) integrity (IBI) has been cited more often (>4,500 times) than any other paper in Fisheries. In this essay, we reflect on the historical context of this seminal publication and its broad, continuing impact on the management of natural resources, especially freshwater ecosystems.
Authors
Paul L. Angermeier, James R. Karr, Chris O. Yoder, Robert M. Hughes

Moose survival and habitat‐associated risk of endoparasites Moose survival and habitat‐associated risk of endoparasites

Parasite-induced morbidity and mortality can alter the trajectories of incidental host populations. Yet, parasites rarely act in isolation and may be one of a multitude of biotic and abiotic stressors that collectively shape mortality risk in vertebrate populations. We quantified sources of mortality in a low-density population of moose (Alces alces) in New York State and investigated...
Authors
Jennifer A. Grauer, Jacqueline L. Frair, Krysten L. Schuler, Manigandan Lejeune, David W. Kramer, Angela K. Fuller

Science

Cooperative Research Unit Locations

To explore our Unit locations, please click the "Study Area" map icon on the right.
Cooperative Research Unit Locations

Cooperative Research Unit Locations

To explore our Unit locations, please click the "Study Area" map icon on the right.
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Where land meets sea: USGS science for resilient coastal habitats

USGS coastal science plays a critical role in supporting the effective, science-based management of coastal ecosystems, where the biodiversity of land and sea meet. It provides managers with the information they need to make sound decisions. Through cutting-edge research, predictive modeling, and decision-support tools, USGS empowers resource managers to make informed, science-based choices. From...
Where land meets sea: USGS science for resilient coastal habitats

Where land meets sea: USGS science for resilient coastal habitats

USGS coastal science plays a critical role in supporting the effective, science-based management of coastal ecosystems, where the biodiversity of land and sea meet. It provides managers with the information they need to make sound decisions. Through cutting-edge research, predictive modeling, and decision-support tools, USGS empowers resource managers to make informed, science-based choices. From...
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Invasive flathead catfish now top predators in Susquehanna River in Pennsylvania

New study suggests that smallmouth bass and channel catfish are changing what they eat to avoid having to compete with or being eaten by the invader
Invasive flathead catfish now top predators in Susquehanna River in Pennsylvania

Invasive flathead catfish now top predators in Susquehanna River in Pennsylvania

New study suggests that smallmouth bass and channel catfish are changing what they eat to avoid having to compete with or being eaten by the invader
Learn More

Multimedia

Dan Ashe, Simon Roosevelt, and Lowell Baier
Dan Ashe, Simon Roosevelt, and Lowell Baier
Dan Ashe, Simon Roosevelt, and Lowell Baier
Lowell Baier (left) and John Organ (right) pose for a picture.
Lowell Baier and John Organ
Lowell Baier and John Organ
Guadalupe Bass
Guadalupe Bass
Guadalupe Bass
Oxbow lake in Mississippi
Oxbow lake in Mississippi
Oxbow lake in Mississippi
Floodplain of the Lower Mississippi River
Floodplain of the Lower Mississippi River
Floodplain of the Lower Mississippi River
Researcher is tagging pronghorn fawn
Researcher is tagging pronghorn fawn in Oklahoma
Researcher is tagging pronghorn fawn in Oklahoma
 Ancient floodplain of the Lower Mississippi River, sometimes known as The Delta.
Ancient floodplain of the Lower Mississippi River, sometimes known as The Delta
Ancient floodplain of the Lower Mississippi River, sometimes known as The Delta
Stream in Arkansas
Stream in Arkansas
Stream in Arkansas
Red spruce forests, once widespread across the central and southern Appalachians, now persist only in scattered fragments on
Red spruce forests in central Appalachia
Red spruce forests in central Appalachia
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