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B.M. Wrege

Publications and source records attributed to B.M. Wrege.

5 recordsLinked to original sources
USGS2011

Diel activity of Gulf of Mexico sturgeon in a northwest Florida bay

In this paper, we assess patterns in activity of Gulf of Mexico sturgeon Acipenser oxyrinchus desotoi over a 24-h period in the Pensacola bay system, Florida. Although seasonal migration of sturgeon is well documented, little information is available pertaining to daily variation in activity. We surgically implanted 58 Gulf sturgeon with acoustic transmitters in the Escambia (n=26), Yellow (n=8), Blackwater (n=12) and Choctawhatchee rivers (n=12) in June, July, September and October 2005. Gulf sturgeon location was monitored using an array of 56 fixed-station acoustic receivers. The relationship between frequency of Gulf sturgeon observations recorded on all acoustic receivers and time of day for all seasons combined indicated a strong diel activity pattern. Gulf sturgeon were frequently detected at night in all seasons with the exception of summer. Consecutive hourly observations indicated lateral movement of Gulf sturgeon between independent acoustic receivers on 15% of all observations of individuals. The use of an acoustic receiver array not only provides continuous data within a defined area, but also provides insight into nocturnal behavior of Gulf sturgeon not previously identified. ?? 2011 Blackwell Verlag, Berlin.

Journal of Applied Ichthyology↗
USGS2011

Seasonal distribution of Gulf of Mexico sturgeon in the pensacola bay system, Florida

Temporal and spatial distributions of Gulf of Mexico (Gulf) sturgeon Acipenser oxyrinchus desotoi were assessed in the Pensacola bay system, Florida, using stationary ultrasonic telemetry. Fifty‐eight Gulf sturgeon were tagged within the Escambia (n = 26), Yellow (n = 8), Blackwater (n = 12) and Choctawhatchee Rivers (n = 12) in June, July, September and October, 2005. Fifty‐four Gulf sturgeon were detected at least once during the study. Migration of sturgeon occurred throughout the bay system in fall, to various winter habitats in the Gulf of Mexico and Santa Rosa Sound. In spring, tagged sturgeon migrated back through the bay system to summer habitats in rivers. Based on the duration and number of detections, Gulf sturgeon primarily used the upper portions of East and Escambia Bays as migration routes in and out of all rivers during spring and summer and inhabited the lower portion of Pensacola Bay for longer durations in fall and winter. Specific areas within the Pensacola bay system were used in summer and winter that were not previously documented as essential sturgeon habitat. Areas in southeastern Pensacola Bay were heavily used during winter by a large portion of the population. Gulf sturgeon also exhibited long‐term winter residency in Santa Rosa Sound for two consecutive years. An area in northeastern Escambia Bay supported Gulf sturgeon during the summer, which was unexpected and can not be explained by the data from this study. However, the discovery that Gulf sturgeon remain in the bay during the summer has important ecological and management implications that need further investigation.

Florida↗
USGS1996

Application of geophysical methods to the delineation of paleochannels and missing confining units above the Castle Hayne aquifer at U.S. Marine Corps Air Station, Cherry Point, North Carolina

The U.S. Marine Corps Air Station, Cherry Point, North Carolina, is underlain by four freshwater-bearing aquifers--the surficial, Yorktown, and upper and lower Castle Hayne. The upper and lower Castle Hayne aquifers serve as the principal supply of freshwater for the Air Station. The potential for movement of contaminated water from the surficial aquifer downward to the water-supply aquifer is greatest in areas where clay confining units are missing. Missing confining units may indicate the presence of paleochannels filled with permeable material. Seismic-reflection techniques were successful in delinea- ting paleochannels of Quaternary and Tertiary age within unconsoli- dated sediments less than 180 feet deep at several locations. Continuous single-channel marine seismic-reflection profiling in the Neuse River was effective in delineating a large paleochannel complex consisting of at least two superimposed paleochannels within hydrogeologic units overlying the upper Castle Hayne aquifer. The complex was found immediately north of the Air Station and is thought to continue south beneath the Air Station. Shallow high-resolution land seismic-reflection techniques were used at the Air Station to delineate structures and correlate strati- graphy between the limestone of the upper Castle Hayne aquifer and the Yorktown confining unit. Three different land seismic-reflection techniques proved effective for the horizontal extrapolation of geo- logic features and identification of paleochannels at several locations. The northeastern margin of a large paleochannel was identified beneath the southern part of the Air Station. This feature strikes northwest to southeast and cuts through the Yorktown and upper Castle Hayne aquifer confining units.

North Carolina↗
USGS1986

Geohydrologic data along the Salt-Gila aqueduct of the central Arizona project in Maricopa and Pinal counties, Arizona

The U.S. Geological Survey, in cooperation with the U.S. Bureau of Reclamation, is conducting an investigation of land subsidence and earth fissures along the Salt-Gila aqueduct to identify hazard zones and to provide design data for the Central Arizona Project aqueducts. Thirty-three test holes were drilled along the Salt-Gila aqueduct of the Central Arizona Project in Maricopa and Pinal Counties. Included in the report are maps showing locations of test holes and vertical extensometer sites, records of test holes, and tables and graphs showing water-level measurements. (USGS)

Open-File Report↗