Documenting bird and bat migration is challenging because migration activity is typically sporadic in nature and nocturnal movements are difficult to observe. The FWS uses avian radar to monitor the timing, duration, and activity patterns of bird and bat migrations along the shorelines of the Great Lakes (http://www.fws.gov/radar/). In fall 2015 and spring 2016, radar units were deployed in northern Michigan along Lake Huron.
Sound (sonar or acoustic)
Changes in sandbar geometry were mapped using historcal and recent aerial imagery to quantify the extent of sandbar encroachment into the water intake structure of the pumping plant for the Buford-Trenton Irrigation District, Williams County, North Dakota. Nine sets of aerial imagery spanning over 60 years and rectified plats from the original 1893 U.S. Geological Survey (USGS) data were used to study changes in the Missouri River extent and course.
Sound navigation and ranging (sonar) data were coupled with historical topographic data to map the extent and volume of silt collected behind the Heart Butte Dam reservoir in southwestern North Dakota. An elevation raster of the land surface submerged beneath the dam was created using sonar with 1–foot (0.3-m) depth intervals collected by the North Dakota Game & Fish Department. To depict the landscape before the dam was created, pre-dam contour and river lines were derived from a historical topographic map obtained from the U.S.
One problem with using divers or remotely operated vehicles to perform underwater inspections of hydraulic structures is that frequently-encountered conditions of poor visibility increase the inspection time and reduce the inspection quality. Commercially available scanning sonar systems can be used to overcome this limitation because sonar works in even highly turbid water to produce detailed images of underwater infrastructure. Scanning sonar can also collect survey-grade bathymetry and three-dimensional (3D) point clouds of underwater features.
Documenting bird and bat migration is challenging because of the typically sporadic nature of migration activity and the difficulty of observing nocturnal movements.
The Water Resources Division of the Region 6 FWS generated elevation data for the creation of a storage-capacity curve for MacFarlane Reservoir, which supplies water to the Arapaho National Wildlife Refuge (ANWR) located in north central Colorado. The reservoir was originally built in 1915, repaired and reconstructed in 1962, and purchased by the FWS in 1993; the reservoir provides nesting and migration habitat for several bird species and is a water source for habitat creation and management at the refuge.
Bat fatalities at wind turbines peak during low wind conditions and primarily involve tree-roosting bats. To investigate the reason for this pattern, USGS researchers and colleagues used thermal surveillance cameras, near-infrared video, acoustic detectors, and radar to monitor bat behavior at a wind farm in Indiana from July to October 2012. During periods of low wind, more bats approached turbines than during periods of high wind. As wind speeds increased, bats more frequently approached turbines from a downwind direction, but only when turbine blades were not turning.
USGS scientists at the Great Lakes Science Center in Michigan are using acoustic telemetry to describe the movements of fish in the St. Clair-Detroit River system on the border between Michigan and Ontario, Canada. This research will be used to support Great Lakes fishery managers in restoring native species, such as lake sturgeon, and controlling exotic species, such as sea lamprey.
The five Laurentian Great Lakes of Superior, Michigan, Huron, Erie and Ontario provide a variety of services to the millions of people that live in the basin. Yet the sheer size of the lakes challenges lake managers’ understanding of how these ecosystems function. USGS scientists at the Great Lakes Science Center in Michigan are combining multiple remote sensing technologies to better understand these vast resources.
A team of scientists from the USGS Upper Midwest Environmental Science Center in La Crosse, Wisconsin, is studying ways to control and deplete aquatic invasive species in the Upper Mississippi River System (UMRS). One study site included a select backwater on the Marseilles Pool in the Illinois River. Split-beam hydroacoustic (stationary and mobile, 200-kHz transducers), side-scan sonar imagery, and bathymetry data were collected and integrated to evaluate fish abundance and distributions in specific areas before, during, and after integrated pest management tools were applied to deplete