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Full-Text Articles in Environmental Indicators and Impact Assessment

Methods For Caculating The Chesapeake Bay Benthic Index Of Biotic Integrity, Roberto J. Llansó, Daniel M. Dauer Jan 2002

Methods For Caculating The Chesapeake Bay Benthic Index Of Biotic Integrity, Roberto J. Llansó, Daniel M. Dauer

Benthic Applications

The Chesapeake Bay benthic index of biotic integrity (B-IBI) was developed to assess benthic community health and environmental quality in Chesapeake Bay. The B-IBI evaluates the ecological condition of a sample by comparing values of key benthic community attributes (“metrics”) to reference values expected under non-degraded conditions in similar habitat types. It is therefore a measure of deviation from reference conditions.

The B-IBI is used by the Chesapeake Bay Benthic Monitoring Program, which is conducted by the Maryland Department of Natural Resources (MD DNR) and by the Virginia Department of Environmental Quality (VA DEQ). The program contains two primary elements: …


Benthic Biological Monitoring Program Of The Elizabeth River Watershed (2000), Daniel M. Dauer Jul 2001

Benthic Biological Monitoring Program Of The Elizabeth River Watershed (2000), Daniel M. Dauer

Elizabeth River Reports

Executive Summary

A study of the macrobenthic communities of the Elizabeth River watershed was initiated in summer 1999. This report presents the data from the second year of sampling in 2000. The three objectives of the Benthic Biological Monitoring Program of the Elizabeth River watershed are: (1) To characterize the health of the tidal waters of the Elizabeth River watershed as indicated by the structure of the benthic communities. ( 2) To conduct trend analyses on long-term data at 14 fixed-point stations to relate temporal trends in the benthic communities to changes in water and/or sediment quality. Trend analyses will …


Casco Bay Watershed Wetlands Characterization, State Planning Office May 2001

Casco Bay Watershed Wetlands Characterization, State Planning Office

Maine Collection

Casco Bay Watershed Wetlands Characterization

State of Maine Executive Department - State Planning Office

Augusta, Maine, May 2001

Contents: Abstract / Background / Getting Started / Designing the System / The Characterization / The Prioritization / Results / Cautions / Significance of the Approach / Literature Cited / Figure 1 - Biophysical Regions of Maine / Appendix A: Steering Committee Members / Appendix B: Field Verification Form / Appendix C: Contacts


Land Use Patterns In Relation To Lake Water Quality In The Lake George And Oaks Pond Watersheds, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College Jan 2001

Land Use Patterns In Relation To Lake Water Quality In The Lake George And Oaks Pond Watersheds, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College

Colby College Watershed Study: Other Area Studies

There has always been an inexplicable wonder associated with the beauty of Maine lakes. In addition to their aesthetic value, lakes and ponds provide important habitats for aquatic and terrestrial wildlife. The attraction of the lake's natural beauty, however, can increase recreational pressures that may lead to human induced eutrophication. Lake George and Oaks Pond were chosen as the Colby Environmental Assessment Team's (CEAT) study sites due to the concern about potential human induced eutrophication of both water bodies. Lake George and Oaks Pond are situated in southern Somerset County, Maine, and experience heavy recreational and developmental uses. Neither water …


Benthic Biological Monitoring Program Of The Elizabeth River Watershed (1999), Daniel M. Dauer Jul 2000

Benthic Biological Monitoring Program Of The Elizabeth River Watershed (1999), Daniel M. Dauer

Elizabeth River Reports

Executive Summary

A study of the macrobenthic communities of the Elizabeth River watershed was conducted in summer 1999. The three objectives of the Benthic Biological Monitoring Program of the Elizabeth River watershed are: (1) To characterize the health of regional areas of the tidal waters of the Elizabeth River watershed Chesapeake Bay as indicated by the structure of the benthic communities. These characterizations are based upon application of benthic restoration goals and the Benthic Index of Biotic Integrity (BIBI) developed for the Chesapeake Bay to five primary strata - the Mainstem of the river, the Lafayette River, the Southern Branch, …


Degradation In The Brockman River And Ellen Brook Catchments, Western Australia, Brian Lloyd Jul 2000

Degradation In The Brockman River And Ellen Brook Catchments, Western Australia, Brian Lloyd

Natural resources published reports

An eight day survey of degradation in the Ellen Brook and Brockman River catchments revealed several areas of concern. Key concerns are:

Erosion and sedimentation

Various forms of erosion were observed during the survey that would cumulatively have an effect on the quality of both the Ellen Brook and the Brockman Rivers, and ultimately the Swan River. Erosion resulted from many situations including landholder management, subdivision design and infrastructure maintenance. Raising awareness as to consequences of erosion and sedimentation, along with remedial techniques and best management practices is recommended for the various levels of stakeholders.

Eutrophication

Eutrophication has been established …


Land Use Patterns In Relation To Lake Water Quality In The Lake Wesserunsett Watershed, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College Jan 2000

Land Use Patterns In Relation To Lake Water Quality In The Lake Wesserunsett Watershed, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College

Colby College Watershed Study: Other Area Studies

The Colby Environmental Assessment Team (CEAT) engaged in an extensive data collection and analysis effort from September to December of 2000 to produce a comprehensive evaluation of the ecological health of the Lake Wesserunsett ecosystem. CEAT examined several factors related to lake water quality, including land use within the watershed, the impacts of residential and commercial development, and physical and chemical measurements of the lake itself. Lake water quality was the primary focus of the study due to its predictive value regarding overall watershed function and viability. The accumulation of nutrients in a lake due to surface runoff and erosion …


Interagency Lake Mead And Las Vegas Wash Monitoring Program: Standard Operating Procedures Manual, Bureau Of Reclamation, City Of Henderson Water Reclamation Facility, City Of Las Vegas Water Pollution Control Facility, Clark County Sanitation District, Nevada, Southern Nevada Water Authority Oct 1998

Interagency Lake Mead And Las Vegas Wash Monitoring Program: Standard Operating Procedures Manual, Bureau Of Reclamation, City Of Henderson Water Reclamation Facility, City Of Las Vegas Water Pollution Control Facility, Clark County Sanitation District, Nevada, Southern Nevada Water Authority

Publications (WR)

A number of agencies sample Lake Mead and the Las Vegas Wash on a routine basis at several locations. In order to share and properly interpret the data, the Bureau of Reclamation, Southern Nevada Water Authority and the three Wastewater Treatment Facilities (City of Las Vegas, Clark County Sanitation District and City of Henderson) formed a committee to examine sampling and analytical protocols and to share information with the goal of maximizing the data quality. The group first met in April 1997. It was agreed that an effort should be made to discuss and compare specific sampling and analytical techniques …


An Inventory And Condition Survey Of The Sandstone-Yalgoo-Paynes Find Area, Western Australia, A L. Payne, A M E Van Vreeswyk, K A. Leighton, H J. Pringle, P Hennig Jan 1998

An Inventory And Condition Survey Of The Sandstone-Yalgoo-Paynes Find Area, Western Australia, A L. Payne, A M E Van Vreeswyk, K A. Leighton, H J. Pringle, P Hennig

Technical Bulletins

The inventory and condition survey of the Sandstone-Yalgoo-Paynes Find area, undertaken by the Department of Agriculture and Food, Western Australia (DAFWA) between 1992 and 1993, describes and maps the natural resources of the region’s pastoral leasehold land. This survey report provides a baseline record of the existence and condition of the area’s natural resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The area surveyed covers about …


Environmental Stress Effects On Vigor, Mortality, And Growth In Northern Hardwood Forests Along A Pollution-Climate Gradient, Neil W. Macdonald, John A. Witter, David R. Reed, Andrew J. Burton, Kurt S. Pregitzer, Hal O. Liechty Jan 1998

Environmental Stress Effects On Vigor, Mortality, And Growth In Northern Hardwood Forests Along A Pollution-Climate Gradient, Neil W. Macdonald, John A. Witter, David R. Reed, Andrew J. Burton, Kurt S. Pregitzer, Hal O. Liechty

Peer Reviewed Publications

Concern exists over the effects of interacting environmental stresses on the ecological integrity of temperate forests. Coincidence of sensitivity to drought, increasing occurrence of defoliation, and elevated pollutant deposition has produced speculation that northern hardwood forests may be susceptible to the increased climatic stresses projected for the Great Lakes region. The objective of our study was to examine relationships among environmental stress factors, vigor, mortality, and growth in northern hardwood forests located along a pollution-climate gradient in the Great Lakes region. Between 1987 and 1993, we quantified climatic variables, pollutant deposition, insect defoliation, and tree vigor and growth at five …


1080 Operational Procedures Manual - Second Edition, Agriculture Western Australia Jan 1998

1080 Operational Procedures Manual - Second Edition, Agriculture Western Australia

Biosecurity published reports

Sodium fluoroacetate (1080) is an extremely toxic substance which can be a danger to humans if handled incorrectly. At the same time 1080 is the most effective and efficient poison for the control of Western Australia's main vertebrate pest species including rabbits, wild dogs and foxes. One of the main reasons for its usefulness in Western Australia is that many native animals have a high tolerance to it and so may not be affected by baiting.

Industry Resource Protection Program (IRPP) This program, part of Agriculture Western Australia, supports feral animal control carried out by its staff and community groups. …


Las Vegas Wash Water Quality Monitoring Program: 1996 Report Of Findings, Richard A. Roline, James J. Sartoris, U.S. Bureau Of Reclamation, U.S. Geological Survey Apr 1997

Las Vegas Wash Water Quality Monitoring Program: 1996 Report Of Findings, Richard A. Roline, James J. Sartoris, U.S. Bureau Of Reclamation, U.S. Geological Survey

Publications (WR)

Las Vegas Wash, a natural wash east of the city of Las Vegas, Nevada, carries stormwater, groundwater drainage, and sewage effluent from three sewage treatment plants to Lake Mead. The Wash provides nearly the only surface water outlet for the entire 2,193 mi2 of Las Vegas Valley. A drainage area of 1,586 mi2 contributes directly to the Wash through surface flow which is channeled to Las Vegas Bay of Lake Mead, while drainage of the remaining 607 mi2 is presumably subsurface and may drain toward Las Vegas Wash.

In the 1930's and 1940's, sewage treatment plants were …


The Influence Of The Wastewater Drainage From The Las Vegas Valley On The Limnology Of Boulder Basin, Lake Mead, Nevada-Arizona, James F. Labounty, Michael J. Horn, Bureau Of Reclamation Jan 1997

The Influence Of The Wastewater Drainage From The Las Vegas Valley On The Limnology Of Boulder Basin, Lake Mead, Nevada-Arizona, James F. Labounty, Michael J. Horn, Bureau Of Reclamation

Publications (WR)

Lake Mead, Colorado River, Arizona-Nevada, is one of the most heavily used reservoirs in the western United States, providing abundant recreational opportunities as well as downstream domestic and agricultural water for over 22 million users. Based on average nutrient levels and productivity, Lake Mead is classified as mildly mesotrophic. The interflow of the Colorado River dominates the limnology of much of the 106 km-long reservoir, and may still be identified at Hoover Dam under certain conditions. The lower basin of Lake Mead ending at Hoover Dam is known as Boulder Basin and is near the Las Vegas metropolitan area. Las …


Land Use Patterns In Relation To Lake Water Quality In The Messalonskee Lake Watershed, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College Jan 1997

Land Use Patterns In Relation To Lake Water Quality In The Messalonskee Lake Watershed, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College

Colby College Watershed Study: Other Area Studies

The main purpose of this study is to assess the current land use patterns and their influences on the water quality of Messalonskee Lake, including the biotic and abiotic parameters which are involved. More specifically, four main objectives were proposed. First, was to calculate the water budget and flushing rate for Messalonskee Lake. Second, was to determine the influence of current and historical land use patterns on lake water quality. Third, was to utilize gathered information to construct a phosphorus model, which will enable future water quality predictions to be made. Our fourth and final objective was to make recommendations …


Report Of Significant Findings--Las Vegas Bay/Boulder Basin Investigations, James F. Labounty, Michael Horn, Bureau Of Reclamation Apr 1996

Report Of Significant Findings--Las Vegas Bay/Boulder Basin Investigations, James F. Labounty, Michael Horn, Bureau Of Reclamation

Publications (WR)

Field sampling was carried out between 0830 and 1500 beginning at the confluence of Las Vegas Wash and the Inner Las Vegas Bay. Ten (10) locations were sampled, each in a similar manner. Locations of sampling stations are in line from the Wash-Bay confluence to a point midway between Saddle and Black Islands. In addition, sampling was done at a location midway between Sentinel Island and the base of Fortification Hill, and at the buoy line in front of Hoover Dam. Sampling stations are labeled from LV01, at Wash-Bay confluence, to LV17 at Hoover Dam. A significant data collection point …


Final Environmental Impact Statement For The Bal'diyaka Interpretive Center At Gregory Point On The Oregon Coast In Coos County, Joseph A. Maser Jan 1996

Final Environmental Impact Statement For The Bal'diyaka Interpretive Center At Gregory Point On The Oregon Coast In Coos County, Joseph A. Maser

Environmental Science and Management Faculty Publications and Presentations

The Confederated Tribes of Coos, Lower Umpqua and Siuslaw Indians, in partnership with the Coos Bay District of the Bureau of Land Management (BLM) are proposing to construct and operate an interpretive center near or on the South Coast of Oregon, near Coos Bay. The Bal'diyaka Interpretive Center is envisioned to contain a 51,000 square foot main building, a recreated coastal Indian village, an ethnobotanical interpretive trail, vehicular circulation and parking, and utilities infrastructure.

This Environmental Impact Statement analyzes four alternatives for this proposed interpretive center. The proposed action of the BLM would locate the Bal'diyaka Interpretive Center on Gregory …


Synthetic Organic Compounds: Las Vegas Wash And Lake Mead, National Water Quality Assessment Program (Nawqa): Nevada Basin And Range Jan 1996

Synthetic Organic Compounds: Las Vegas Wash And Lake Mead, National Water Quality Assessment Program (Nawqa): Nevada Basin And Range

Publications (WR)

The Nevada Basin and Range (NVBR) study unit of the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program is investigating the status of, trends in, and factors affecting water quality in the Las Vegas area. A principal objective of the investigation is to assess the effects of urbanization on the quality of area water resources. Las Vegas Wash is the surface-water outlet for the Las Vegas area. The wash transports stormwater runoff, shallow ground-water discharge, and tertiary-treated sewage effluent from the Las Vegas area to Las Vegas Bay of Lake Mead on the Colorado River. Most of the flow—about 96 …


Nutrient Limitation In A Southwestern Desert Reservoir: Eutrophication Of Las Vegas Bay, Lake Mead, Nevada, Davine M. Lieberman Sep 1995

Nutrient Limitation In A Southwestern Desert Reservoir: Eutrophication Of Las Vegas Bay, Lake Mead, Nevada, Davine M. Lieberman

Publications (WR)

Algal bioassay tests were conducted with Selenastrum capricornutum and natural algae on inner Las Vegas Bay, Lake Mead, Nevada, from December 1992 through September 1993, to identify any nutrient limitation in an area of the reservoir that has experienced problems associated with severe nutrient enrichment. Three areas were sampled based on a gradient of water quality conditions that existed in Las Vegas Bay (LVB). Disodium ethylenedinitrilotetraacetate (EDTA) significantly stimulated algal growth compared to non-EDTA treatment. Algal bioassays indicated that phosphorus (P) was the primary limiting nutrient at all stations for most of the test dates. Chl a response with EDTA …


Baseline Water Quality Data Inventory And Analysis: Lake Mead National Recreation Area, Volume Ii Of Ii, National Park Service Dec 1994

Baseline Water Quality Data Inventory And Analysis: Lake Mead National Recreation Area, Volume Ii Of Ii, National Park Service

Publications (WR)

This document presents the results of surface-water-quality data retrievals for Lake Mead National Recreation Area (LAME) from five of the United States Environmental Protection Agency's (EPA) national databases: (1) Storage and Retrieval (STORET) database management system; (2) River Reach File (RF3); (3) Industrial Facilities Discharge (IFD); (4) Drinking Water Supplies (DRINKS); and (5) Flow Gages (GAGES). This document is one product resulting from a cooperative contractual endeavor between the National Park Service's Servicewide Inventory and Monitoring Program, the National Park Service's Water Resources Division (WRD), and Horizon Systems Corporation to retrieve, format, and analyze water quality data for all units …


Baseline Water Quality Data Inventory And Analysis: Lake Mead National Recreation Area, Volume I Of Ii, National Park Service Dec 1994

Baseline Water Quality Data Inventory And Analysis: Lake Mead National Recreation Area, Volume I Of Ii, National Park Service

Publications (WR)

This document presents the results of surface-water-quality data retrievals for Lake Mead National Recreation Area (LAME) from five of the United States Environmental Protection Agency's (EPA) national databases: (1) Storage and Retrieval (STORET) database management system; (2) River Reach File (RF3); (3) Industrial Facilities Discharge (IFD); (4) Drinking Water Supplies (DRINKS); and (5) Flow Gages (GAGES). This document is one product resulting from a cooperative contractual endeavor between the National Park Service's Servicewide Inventory and Monitoring Program, the National Park Service's Water Resources Division (WRD), and Horizon Systems Corporation to retrieve, format, and analyze water quality data for all units …


An Inventory And Condition Survey Of The Murchison River Catchment, Western Australia, Peter James Curry, A L. Payne, K A. Leighton, P Hennig, D A. Blood Jan 1994

An Inventory And Condition Survey Of The Murchison River Catchment, Western Australia, Peter James Curry, A L. Payne, K A. Leighton, P Hennig, D A. Blood

Technical Bulletins

The inventory and condition survey of the Murchison River catchment and surrounds, undertaken by the Department of Agriculture between 1985 and 1988, describes and maps the natural resources of the region’s pastoral leasehold land. This survey report provides a baseline record of the existence and condition of the natural area’s resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The area surveyed by field work during 1985-88 …


An Inventory And Condition Survey Of Rangelands In The North-Eastern Goldfields, Western Australia, H J. Pringle, S A. Gilligan, A M E Van Vreeswyk Jan 1994

An Inventory And Condition Survey Of Rangelands In The North-Eastern Goldfields, Western Australia, H J. Pringle, S A. Gilligan, A M E Van Vreeswyk

Technical Bulletins

The inventory and condition survey of the north-eastern Goldfields, undertaken by the Department of Agriculture and Food, Western Australia (DAFWA) between 1988 and 1990, describes and maps the natural resources of the region’s pastoral leasehold land. This survey report provides a baseline record of the existence and condition of the natural area’s resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The area surveyed covers about 100 …


Identification Of Tire Leachate Toxicants And A Risk Assessment Of Water Quality Effects Using Tire Reefs In Canals, S. M. Nelson, G. Mueller, D. C. Hemphill, U.S. Bureau Of Reclamation Jan 1994

Identification Of Tire Leachate Toxicants And A Risk Assessment Of Water Quality Effects Using Tire Reefs In Canals, S. M. Nelson, G. Mueller, D. C. Hemphill, U.S. Bureau Of Reclamation

Publications (WR)

Cover is an important component of aquatic habitat and fisheries management. Fisheries biologists often try to improve habitats through the addition of natural and artificial material to improve cover diversity and complexity. Habitat-improvement programs range from submerging used Christmas trees to more complex programs using sophisticated artificial habitat modules. Used automobile tires have been employed in the large scale construction of reefs and fish attractors in marine environments and to a lesser extent in freshwater and have been recognized as a durable, inexpensive and long-lasting material which benefits fishery communities.

Recent studies by the U.S. Bureau of Reclamation have quantified …


A Review Of Plant Introductions To The Kimberley 1955 To 1987, R Mccartney Nov 1991

A Review Of Plant Introductions To The Kimberley 1955 To 1987, R Mccartney

Grain and other field crops published reports

This report summarizes the work done by the Department of Agriculture, Western Australia, in the west and north Kimberley in introducing plant species during 1955-1987.

For the purposes of this repor1the following areas are defined thus:

• West Kimberley- lies between latitude 17°5 and 19°5 and longitude 121°E and 127°E, with an extension to the north of 1° between 121°E and I 24°20'E. The area is 118,000 km".

• North Kimberley - lies north of latitude 17°5 and between longitude 124°20'E and 127°30'E. The area is 85,000 km'.

• East Kimberley-lies north of latitude 19°5 and between longitude 127°30'E and …


The Identification, Distribution, And Status Of The Threatened Dismal Swamp Shrew (Sorex Longirostris Fisheri), Thomas M. Padgett Oct 1991

The Identification, Distribution, And Status Of The Threatened Dismal Swamp Shrew (Sorex Longirostris Fisheri), Thomas M. Padgett

Biological Sciences Theses & Dissertations

Southeastern shrews (Sorex longirostris) were trapped throughout southeastern Virginia and northeastern North Carolina to determine if any morphological characters could

be identified that would aid in the identification and distribution of the threatened subspecies Sorex l._ fisheri, endemic to the Great Dismal Swamp, the more upland nominate subspecies Sorex l. longirostris, and possible intergrades between the two subspecies. Animals were classified a priori into three groups, based on their location of capture. Animals collected from the Great Dismal Swamp National Wildlife Refuge (GDSNWR) and associated bottomland habitats were designated as "fisheri", animals collected farthest from the Swamp as "longirostris", and …


Community Structure Of The Macrobenthos In Back Bay, Virginia, Michael F. Lane Oct 1991

Community Structure Of The Macrobenthos In Back Bay, Virginia, Michael F. Lane

Biological Sciences Theses & Dissertations

A study of the subtidal macrobenthos in Back Bay, Virginia was conducted to examine community structure in relation to sedimentary and water quality characteristics. Samples were collected in August and November of 1987 and February and May of 1988 at ten stations.

Three site groups and three temporal groups were identified by cluster analyses of species abundance. Species composition between site groups was relatively homogeneous and eight species accounted for most of the variation between site groups. A comparison of plots of the biological and physical data in discriminant space suggested that variations in the biological data between site groups …


Littoral And Limnetic Zooplankton Communities In Lake Mead, Nevada-Arizona, Usa, Patrick J. Sollberger, Larry J. Paulson Jan 1991

Littoral And Limnetic Zooplankton Communities In Lake Mead, Nevada-Arizona, Usa, Patrick J. Sollberger, Larry J. Paulson

Publications (WR)

Zooplankton were collected from adjacent littoral and limnetic sites in Lake Mead, Nevada-Arizona, USA. Limnetic species dominated both littoral and limnetic zooplankton communities; littoral species rarely exceeded 2% of monthly total zooplankton densities. Low species richness of littoral taxa and high similarity in species composition between littoral and limnetic habitats appeared to result from uniform horizontal physical and chemical environments, due to horizontal mixing, and from the absence aquatic macrophytes. Significant differences in spatial distribution occurred in phytoplankton biomass, total zooplankton density, and fish "abundances; highest concentrations of these factors occurred nearest an inflow high in nutrients and progressively declined …


Lake Mead Nutrient Enhancement Project, Peter D. Vaux, Larry J. Paulson, Nevada Department Of Wildlife, National Oceanic And Atmospheric Administration Dec 1990

Lake Mead Nutrient Enhancement Project, Peter D. Vaux, Larry J. Paulson, Nevada Department Of Wildlife, National Oceanic And Atmospheric Administration

Publications (WR)

The Lake Mead Fertilization Project is a research program designed to investigate the potential for using large-scale artificial fertilization to enhance the game fisheries of this reservoir through an increase in the population of threadfin shad, the system's primary forage species. A substantial decline in the population of largemouth bass, together with poor condition of adult striped bass, are the two major issues affecting the Lake Mead game fisheries. Both issues have been hypothesized to be a result of an inadequate amount of forage in the reservoir. Previous studies have in turn suggested that a major factor limiting the shad …


Enhancement And Monitoring Of The Procambarus Clarkii Population In Lake Mead, Mikell Beth Hager May 1990

Enhancement And Monitoring Of The Procambarus Clarkii Population In Lake Mead, Mikell Beth Hager

Publications (WR)

Procambarus clarkii are found in extremely low numbers throughout Lake Mead, AZ-NV. The crayfish are an important dietary component for game fish. Enhancement of the crayfish population would broaden the fishery forage base. Crayfish were stocked and monitored in a study cove on Saddle Island to determine if the Procambarus clarkii population could be enhanced. A trapping survey of the area after the following reproductive season yielded low numbers of crayfish. A comparison of pre-stocking and post-stocking catch per trap day (CPTD) values revealed no significant increase in the population. Procambarus clarkii growth is limited by environmental factors in Lake …


A Resource Inventory And Impact Analysis Of Great Bog And The Horse Point Delta/Esker System, Problems In Environmental Science Course (Biology 493), Colby College, Biologists Organized For Ecosystem Assessment, Colby College Jan 1990

A Resource Inventory And Impact Analysis Of Great Bog And The Horse Point Delta/Esker System, Problems In Environmental Science Course (Biology 493), Colby College, Biologists Organized For Ecosystem Assessment, Colby College

Colby College Watershed Study: Other Area Studies

In May of 1990, Tilcon-Maine, Inc. submitted an application to mine gravel on the east side of Horse Point Road on Horse Point in the Town of Belgrade. The project site covers 46 acres and the proposed excavation covers 16 acres. An estimated 740,000 cubic yards of material will be removed over a period of six or seven years (Pfister, pers. comm.). According to Tilcon (Timson et al., 1990) the maximum depth of the pit will be 78 feet and the bottom of the pit will be a minimum of 6 feet above the water table. At the present time …