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Carter R. Gilbert

Publications and source records attributed to Carter R. Gilbert.

7 recordsLinked to original sources
USGS2005

Prey vulnerability to peacock cichlids and largemouth bass based on predator gape and prey body depth

The interaction of prey fish body depth and predator gape size may produce prey assemblages dominated by invulnerable prey and excessive prey-to-predator biomass ratios. Peacock cichlids (Cichla ocellaris) were stocked into southeast Florida canals to consume excess prey fish biomass, particularly spotted tilapia (Tilapia mariae). The ecomorphologically similar largemouth bass (Micropterus salmoides) was already present in the canals. We present relations of length-specific gape size for peacock cichlids and largemouth bass. Both predators have broadly overlapping gape size, but largemouth bass ?126 mm total length have slightly larger gape sizes than peacock cichlids of the same length. Also, we experimentally tested the predictions of maximum prey size for peacock cichlids and determined that a simple method of measuring gape size used for largemouth bass also is appropriate for peacock cichlids. Lastly, we determined relations of body depth and length of prey species to investigate relative vulnerability. Using a simple predator-prey model and length frequencies of predators and bluegill (Lepomis macrochirus), redear sunfish (Lepomis microlophus), and spotted tilapia prey, we documented that much of the prey biomass in southeast Florida canals is unavailable for largemouth bass and peacock cichlid predation.

Florida↗
USGS1967

Floods on White Rock Creek at Dallas, Texas in 1962 and 1964

This atlas presents data pertaining to the regimen of flooding along White Rock Creek and its tributaries, Spanky Branch, Floyd Branch, and Cottonwood Creek at Dallas, Texas. The map and flood data were prepared to aid those concerned with, and responsible for, the safe and yet extensive use of the floodplain along White Rock Creek and its tributaries. The flood map is shown in two parts—A, north half, and B, south half. The map shows areas inundated by the flood of September 21, 1964, along White Rock Creek and Spanky Branch and by the flood of October 8, 1962, along Cottonwood Creek and Floyd Branch. The flood of September 21, 1964, is known to be the greatest since at least 1886 on White Rock Creek upstream from the Texas and Pacific Railroad (mile 6.6). Downstream from the Texas and Pacific Railroad, White Rock Creek has been subject to inundation from backwater from the Trinity River. The greatest known flood on Trinity River occurred May 25, 1908. Because of extensive flood-control works built since 1908 in the upper Trinity River basin, the degree of flooding resulting from a storm of the magnitude of the 1908 catastrophe probably would be substantially different today. No backwater from Trinity River occurred during the flood of September 21, 1964. The greatest flood since at least 1892 on Cottonwood Creek and Floyd Branch occurred June 14, 1949. The storm of October 8, 1962, caused flood heights at Forest Lane to be comparable to those of June 14, 1949, on Cottonwood Creek and about 1 foot lower on Floyd Branch. The greatest flood since at least 1917 on Spanky Branch was that of September 21, 1964. Greater floods than those delineated are possible.

Texas↗
USGS1965

Base-flow studies Nueces River, Texas quantity and quality, November 23-25, 1964

An investigation was made by the U.S. Geological Survey, under a cooperative agreement with the Texas Water Development Board, to determine the changes in quantity and chemical quality of the base flow of the Nueces River in a 52.2-mile reach beginning at U.S. Highway 90 and extending to the crossing of Farm Road 1025 north of Crystal City. Knowledge of the changes in quantity and chemical quality of base flow is necessary for any evaluation of the effectiveness of the river channel in conveying water released from potential upstream reservoirs. The investigation was made November 23-25, 1964, during a period when evaporation and transpiration were small and the discharge past the stream-gaging station, Nueces River below Uvalde, was constant. Floods of September 1964 contributed considerably to the recharge of the alluvium in the reach investigated, resulting in a higher than average base flow.

Texas↗