Geology topics

Research about Valley County, Idaho

Source-linked reports with geographic coverage including Valley County, Idaho.

3 recordsLinked to original sources

USGS2022

Drones and bathymetry show the importance of optimal water depth for nest placement within breeding colonies of Western and Clark’s grebes

Habitat selection involves a series of decisions that are arguably the most important decisions that animals make and these decisions occur at multiple hierarchical spatial scales. Colonial-nesting birds face a unique challenge when selecting a nest site because each bird’s choices are severely constrained by other birds within their breeding colony. Individuals must seek out optimum nesting locations within the constraint of the colony’s geographic location. We investigated how water depth and proximity to open water affected 4th-order nest-site selection of Western and Clark’s Grebes ( Aechmophorus occidentalis, Aechmophorus clarkii ), colonial nesting waterbirds that have declined in abundance across their range. We used an orthomosiac that we created from ~ 500 aerial drone images of a large breeding colony to construct a Resource Selection Function to describe microhabitat features that influence nest-site placement within the colony footprint. Grebes preferred to nest in portions of the colony with intermediate water depths (40-80 cm during nest construction) and they preferred to nest in portions of the colony furthest from open water. Understanding how individual birds make use of available microhabitat features within the footprint of their breeding colony can help inform conservation efforts of colonial-nesting birds, particularly for species that nest in wetland habitats whose water levels are managed for human use.

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USGS2020

Drones provide a better method to find nests and estimate nest survival for colonial waterbirds: A demonstration with Western Grebes

Drone use in wildlife biology has greatly increased as they become cheaper and easier to deploy in the field. In this paper we describe a less invasive method of using drones and exploring their limitations for studying colonial nesting waterbirds. Western Grebes, like most colonial nesting waterbirds, can be very sensitive to human interaction. Using a 3DR Solo quad copter equipped with a high-resolution digital camera we were able to effectively map and monitor a Western Grebe breeding colony throughout the nesting period with a series of 6 flights. We were able to use drone collected aerial imagery to model nest survival while minimizing disturbance to the birds. However, we were not able to deploy the drone at all of our study sites. Our ability to effectively deploy the drone was hindered by the environmental and vegetation characteristics of a site. Drone technology can be a useful tool, especially when studying a species sensitive to human interaction. However, there researchers should carefully consider their species and study site to evaluate if a drone is the proper tool to meet their objectives.

Idaho↗

USGS2017

Glacial sequence near McCall, Idaho: Weathering rinds, soil development, morphology, and other relative-age criteria

The sequence of glacial deposits near McCall, Idaho, previously assigned to the Pinedale and Bull Lake glaciations, contains deposits of four different ages. These ages are defined by multiple relative-age criteria, including weathering rinds, soil development, surface-rock weathering, morainal morphology, and loess stratigraphy. The thickness of weathering rinds on basaltic clasts is statistically representative and reproducible and can be used to estimate numerical ages. Following in order of decreasing relation to age are soil development, surface-rock weathering, and moraine morphology. The glacial deposits near McCall appear to correspond to times of high worldwide ice volume indicated by the marine oxygen-isotope record. Pilgrim Cove and McCall deposits, both assigned to the Pinedale glaciation, are late Wisconsin in age, perhaps 14,000 and 20,000 years, respectively. They represent a rare case in which deposits of Pinedale age can be separated by relative-age data. Timber Ridge deposits, assigned to the Bull Lake glaciation, have subdued, but well-preserved morainal morphology; relative-age data indicate that they are pre-Wisconsin in age, probably about 140,000–150,000 years old, although we cannot exclude an older age. Williams Creek deposits are clearly distinct from, and intermediate in age between, McCall and Timber Ridge deposits. Weathering rinds and the inferred ages of the other deposits suggest an early Wisconsin age for Williams Creek deposits.

Idaho↗