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Articles 1021 - 1050 of 1349

Full-Text Articles in Aquaculture and Fisheries

Effects Of Moonlight And Daylight On Hydroacoustic Estimates Of Pelagic Fish Abundance, Chris Luecke, Wayne A. Wurtsbaugh Jan 1993

Effects Of Moonlight And Daylight On Hydroacoustic Estimates Of Pelagic Fish Abundance, Chris Luecke, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

To determine how moonlight and daylight affect hydroacoustic estimates of fish abundance, we used a dual-beam transducer and echo integration to survey pelagic fish (primarily Bonneville ciscoes Prosopium gemmifer) in Bear Lake, Utah and Idaho. During the new moon, the fish were dispersed (not schooling) below the thermocline, chiefly at the depths of 10–20 m. At full moon, they were dispersed but much closer to the bottom, where they were difficult to detect. Acoustic estimates offish density and biomass during full moons were approximately 50% of values derived during new moons. A diel survey during a new moon indicated that …


An Empirical Model Of Gastric Evacuation Rates For Fish And An Analysis Of Digestion In Piscivorous Brown Trout, E. He, Wayne A. Wurtsbaugh Jan 1993

An Empirical Model Of Gastric Evacuation Rates For Fish And An Analysis Of Digestion In Piscivorous Brown Trout, E. He, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

The gastric evacuation rates of brown trout Salmo trutta (0.9–1.6 kg) feeding on fingerling rainbow trout Oncorhynchus mykiss (3.5–7.6 g) were measured in the laboratory at five temperatures (4.5, 9.0, 14.0, 19.0, and 22.5°C). Instantaneous gut evacuation rates (Re) increased exponentially with temperature (T): Re = 0.053se^0.073T, r^2 = 0.98; they varyied from 7%sh^–1 at 4.5°C to 29%sh^–1 at 22.5°C. Linear regressions described the relationship between time and qualitative measures of fish digestion, thus allowing investigators to determine how long an ingested fish would be identifiable at different temperatures. An analysis of published evacuation rates (N = 121) of 22 …


Snake River Sockeye Salmon Habitat And Limnological Research, David Teuscher, Doug Taki, Wayne A. Wurtsbaugh Jan 1993

Snake River Sockeye Salmon Habitat And Limnological Research, David Teuscher, Doug Taki, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Historically, thousands of Snake River Sockeye salmon returned to the Sawtooth Valley to spawn. Evermann (1896) reported that the Sawtooth Valley Lakes were teeming with red fish. Bjornn (196~) estimated that 4,360 sockeye returned to Redfish Lake in 1955. These numbers no longer exist. In the 1980's, less than 50 Snake River sockeye salmon survived to spawn (Bowler 1990). Since 19-90, only 13 sockeye have returned. Because of recent declines, the Shoshone-Bannock Tribes (SBT) petitioned the National Marine Fisheries Service (NMFS-) to list Snake River sockeye as endangered. As a result, Snake River sockeye were listed and the Bonneville Power …


Inventory Of Rare Plant Species In The Pine Ridge Area Of Nebraska (Dawes And Sioux County, Nebraska), Michael I. Fritz, Joyce Philips Hardy, Steven B. Rolfsmeier Dec 1992

Inventory Of Rare Plant Species In The Pine Ridge Area Of Nebraska (Dawes And Sioux County, Nebraska), Michael I. Fritz, Joyce Philips Hardy, Steven B. Rolfsmeier

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

The purpose of this project was to conduct a systematic inventory of rare plant species on the Pine Ridge District of the Nebraska National Forest. The objective of the inventory was to locate rare plant occurrences and compile information on their location, status and any possible threats. Four areas within the Pine Ridge District were identified as priority areas for the inventory fieldwork. The four tracts included the Soldier Creek Wilderness Area, a tract encompassing the East and West Ash Creek drainages, a middle unit tract, and a tract which straddles U.S. Highway 385 and encompasses a number of timber …


Southern Nevada Effluent Wetlands: A Proposed Cooperative Venture Between The Bureau Of Reclamation & City Of Las Vegas, Bureau Of Reclamation Nov 1992

Southern Nevada Effluent Wetlands: A Proposed Cooperative Venture Between The Bureau Of Reclamation & City Of Las Vegas, Bureau Of Reclamation

Publications (WR)

Throughout North America there is a growing interest in constructed wetlands, both as relatively inexpensive, low-maintenance systems for removing nutrients from wastewater, and as a means of using municipal wastewater to enhance wildlife habitat and create public use opportunities. Because wetlands appear to have good potential as a component in the overall management of scarce water resources, the Bureau of Reclamation (Reclamation) has undertaken several cooperative research and demonstration projects to evaluate their effectiveness in a variety of local environments. While a number of projects have demonstrated that wetlands can be beneficially employed to improve water quality, few such projects …


The Influence Of Redd Distribution And Microhabitat Availability On The Distribution And Abundance Of Young-Of-The-Year Trout In The Green River, Utah, Michael J. Buntjer May 1992

The Influence Of Redd Distribution And Microhabitat Availability On The Distribution And Abundance Of Young-Of-The-Year Trout In The Green River, Utah, Michael J. Buntjer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Redd distribution, redd density, and physical habitat were used to explain the distribution and abundance of young-of-the-year (YOY) brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss) in the Green River, Utah. The importance of variables at both a microhabitat and macrohabitat scale were assessed using stepwise regression analysis. Availability of cover (rock and vegetation) and proximity to spawning sites were the most important variables used to explain the distribution and abundance of YOY brown trout and rainbow trout. In addition, YOY brown trout and rainbow trout occupied specific microhabitats and showed patterns of use for …


Sea-Surface Temperature Related Fisheries And Resource Markets, Jeffrey Michael Rasinski Jan 1992

Sea-Surface Temperature Related Fisheries And Resource Markets, Jeffrey Michael Rasinski

Marine Affairs Theses and Major Papers

This thesis addresses the potential application of sea-surface temperature (SST) data to economic resource markets. It considers the revolution in technology and the accessibility of timely, accurate SST observations for resource markets. Specifically, it addresses issues related to pelagic fisheries and the fish meal industry. The thesis presents a discussion and overview of the upwelling ecosystem of Peru and the Peruvian anchovy (Engraulis ringens) including quantitative analysis and forecasts for the fishery and fish meal prices. This analysis is used to demonstrate the commercial application and relationship between SST and related resource markets. The thesis establishes a bioeconomic statistical model …


Visual Feeding By Juvenile Bear Lake Sculpin, D. Neverman, Wayne A. Wurtsbaugh Jan 1992

Visual Feeding By Juvenile Bear Lake Sculpin, D. Neverman, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Young-of-the-year Bear Lake sculpin Cottus extensus feed throughout the day on benthic invertebrates and cease feeding at night when they migrate to the metalimnion. We investigated their reliance on vision by conducting feeding trials at different light levels in the laboratory. Feeding rate reached a maximum at intermediate light levels (near 10^16 photons sm^–2 ss^–1; approximately 1 lux) but decreased as light intensity increased beyond this range. At this maximum rate, the fish fed nine times faster than they were able to feed in the dark, showing that young Bear Lake sculpin rely heavily upon vision to feed. The light …


A Trophic Gradient Analysis Of Lake Powell During Spring Runnoff 1992, Wayne A. Wurtsbaugh, Clyde Lay, Darren Carlise, Corey Huxol, Craig Schaugaard, Beau Clements, David Beauchamp Jan 1992

A Trophic Gradient Analysis Of Lake Powell During Spring Runnoff 1992, Wayne A. Wurtsbaugh, Clyde Lay, Darren Carlise, Corey Huxol, Craig Schaugaard, Beau Clements, David Beauchamp

Watershed Sciences Faculty Publications

Between 26 April and 2 May 1992, students in a utah state university aquatic ecology class visited Lake Powell to do a study of trophic gradients of the reservoir. The main axis of the reservoir was surveyed, as well as less detailed analyses of Moki and Escalante Canyons. The work was conducted in collaboration with personnel from the u.s. Bureau of Reclamation headed by Bill Vernieu, and from the u.s. Geological Survey (Dick Marzolf). Some of their data appear in the physical-chemical section of this report.

Each student was responsible for compiling a report on one of the following specific …


Snake River Sockeye Salmon (Oncorhynchus Nerka) Habitat/Limnologic Research, Scott Spaulding, Wayne A. Wurtsbaugh, Shoshone-Bannock Tribe Jan 1992

Snake River Sockeye Salmon (Oncorhynchus Nerka) Habitat/Limnologic Research, Scott Spaulding, Wayne A. Wurtsbaugh, Shoshone-Bannock Tribe

Watershed Sciences Faculty Publications

This report outlines long-term planning and monitoring activities that occurred in 1991 and 1992 in the Stanley Basin Lakes of the upper Salmon River, Idaho for the purpose of sockeye salmon (Oncorhynchus nerka) recovery. Limnological monitoring and experimental sampling protocol, designed to establish a limnological baseline and to evaluate sockeye salmon production capability of the lakes, are present:ed. Also presented are recommended passage improvements for current fish passage barriers/impediments on migratory routes to the lakes. We initiated O. Nerka population evaluations for Redfish and Alturas lakes; this included population estimates of emerging kokanee fry entering each lake in the spring …


Lake Trout Spawning In Lake Tahoe: Egg Incubation In Deepwater Macrophyte Beds, D. A. Beauchamp, B. C. Allen, R. C. Richards, Wayne A. Wurtsbaugh, C. R. Goldman Jan 1992

Lake Trout Spawning In Lake Tahoe: Egg Incubation In Deepwater Macrophyte Beds, D. A. Beauchamp, B. C. Allen, R. C. Richards, Wayne A. Wurtsbaugh, C. R. Goldman

Watershed Sciences Faculty Publications

Although most populations of lake trout Salvelinus namaycush spawn over rocky shoals, use of these substrates by lake trout has not yet been found in Lake Tahoe. Large cobble substrate exists at depths less than 20 m, and steep, fractured, rocky substrate can be found in isolated areas from the surface down to at least 100 m, but no evidence of spawning activity in these areas has been found. Instead, at least a portion of the population spawns on deepwater mounds (40–60 m deep) over beds of the macrophyte Chara delicatula. This is the first known report of lake trout …


Population Status And Characteristics Of Macrhybopsis Gelida, Platygobio Gracilis And Rhinichthys Cataractae In The Missouri River Basin, Selena J. Werdon Jan 1992

Population Status And Characteristics Of Macrhybopsis Gelida, Platygobio Gracilis And Rhinichthys Cataractae In The Missouri River Basin, Selena J. Werdon

Electronic Theses and Dissertations

Few sturgeon chub (Macrhybopsis gelida: Cyprinidae) have been collected in the last decade, therefore their status, habitat selection and morphology were investigated at 172 previous collection sites. Data on two ecologically similar species, Platygobio gracilis and Rhinichthys cataractae, were also collected. Macrhvbopsis gelida were collected at 28 sites on the Powder River (n = 158) in Wyoming and Montana, and at one site on the Yellowstone River (n = 1) in Montana. Age-I, Age-II and Age-III M. gelida were collected. Specimens were 37 to 95 mm in total length. Macrhvbopsis gelida were ripe in mid-June, at water temperatures of 18.3-22. …


A Study Of The Summer Steelhead, Oncorhynchus Mykiss In Several Intermittent Tributaries Of The Satus Creek Basin, Washington, Joel Denney Hubble Jan 1992

A Study Of The Summer Steelhead, Oncorhynchus Mykiss In Several Intermittent Tributaries Of The Satus Creek Basin, Washington, Joel Denney Hubble

All Master's Theses

The summer steelhead, Oncorhynchus mykiss population was studied in three intermittent tributaries in the Satus Creek Basin. There was a strong tendency for post emergent fry, resulting from redds located in intermittent reaches to move downstream. However, survival to perennial flow conditions was very low. Steelhead production in Dry Creek appears to be lower than in Logy Creek, because of elevated water temperatures and minimal spring and summer stream flow.


State Of The Fisheries Report 1991, Fisheries Department Of Western Australia Dec 1991

State Of The Fisheries Report 1991, Fisheries Department Of Western Australia

Status Reports of the Fisheries and Aquatic Resources

The State of the Fisheries is published annually by the Fisheries Department as part of the statutory reporting process required under the Fisheries Act. This report covers developments and production in the State's fisheries up to the end of December 1991. Full details of the department's operations for this period are published separately in the department's annual reports for the financial years ending June 1991 and 1992. Figures provided in the tables are derived from catch returns completed by fishermen which are processed by the Australian Bureau of Statistics up to June 1991. Other information provided in the text comes …


Appendix To The Final Report Of The Rfac. Statistical Summary Of Public Responses To Key Issues., Recreational Fishing Advisory Committee Western Australia. May 1991

Appendix To The Final Report Of The Rfac. Statistical Summary Of Public Responses To Key Issues., Recreational Fishing Advisory Committee Western Australia.

Fisheries Management Papers

This paper has been published as a separate appendix to the final report of the Recreational Fishing Advisory Committee, and should be read in conjunction with it, and the Committee's discussion paper ("Final report of the Recreational Fishing Advisory Committee - Fisheries Management Paper No. 41 1991). The key issues that were identified in the discussion paper came up under the following headings: 5.1 Environment 5.2 Resource Sharing 5.3 Access for Fishing 5.4 Research 5.5 Management rules 5.6 Enforcement 5.7 Charter fishing 5.8 Funding and licensing 5.9 Community consultation 5.10 Public awareness and community education.


Is Rainbow Trout Condition Influenced By Invertebrate-Drift Density?, Randall B. Filbert May 1991

Is Rainbow Trout Condition Influenced By Invertebrate-Drift Density?, Randall B. Filbert

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Users of the Instream Flow Incremental Methodology CTFIM) commonly assume that there is a positive linear relationship between available habitat (WUA) and stream fish biomass. However, several studies have shown a lack cf correlation between WUA and biomass. Such poor relationships may occur if other factors limit fish abundance. Food availability is a potentially important factor limiting abundance of stream fishes and can affect blomass by influencing fish condition (individual weight). I collected rainbow trout (Oncorhynchus mykiss) exposed to different levels of invertebrate-drift density to determine if condition was greater where food was more abundant. I also examined …


Fisheries Research Report No 91 - A Synopsis Of The Biology And The Exploitation Of The Australasian Pilchard, Sardinops Neopilchardus (Steindachner) Part Ii: History Of Stock Assessment And Exploitation, W. J. Fletcher Mar 1991

Fisheries Research Report No 91 - A Synopsis Of The Biology And The Exploitation Of The Australasian Pilchard, Sardinops Neopilchardus (Steindachner) Part Ii: History Of Stock Assessment And Exploitation, W. J. Fletcher

Fisheries Research Reports

This report summarises the studies which have provided information on the population characteristics and exploitation of the pilchard, Sardinops neopilchardus in Australia and New Zealand. This review was undertaken to determine whether existing data could be used to assess the status of Western Australian or other stocks or, alternatively, what additional information was required.

The mean size of pilchards caught varies among locations but, in general, fish are between 140 and 160 mm LCF, corresponding to ages 2 - 5 years. The length-weight relationship also varies between locations

Attempts to initiate pilchard fisheries have been hampered by the lack of …


Mariculture Management For Pohnpei State, Federated States Of Micronesia, Kevin Brooks Foster Jan 1991

Mariculture Management For Pohnpei State, Federated States Of Micronesia, Kevin Brooks Foster

Marine Affairs Theses and Major Papers

The Marine Resources Division of Pohnpei State, Federated States of Micronesia is currently engaged in development activities that include the establishment of family scale mariculture projects for community members of remote villages and outer islands. The goal of this undertaking is to supplement subsistence and income generation ventures for community members through the wise use and exploitation of the marine environment. These aims may be jeopardized unless a management plan is devised that reflects the customary marine resource practices as embraced by islanders from each community. The intent of this thesis projects is to devise a mariculture management model that …


Prospects For Fisheries Development In West Africa, Steven K. Ireland Jan 1991

Prospects For Fisheries Development In West Africa, Steven K. Ireland

Marine Affairs Theses and Major Papers

The production of food is a primary concern for the countries of Africa. Marine fisheries can contribute toward alleviating undernutrition and provide employment opportunities in developing countries. In West Africa there are substantial marine fisheries resources but there is a need for development and improved management of these resources. Fisheries development efforts have thus far achieved limited success in the region. However, there is considerable potential for increasing the contribution of fisheries to economic development if the problems of fisheries development can be overcome.


Malaysia And The Law Of The Sea, Mohd Fadzil Shuhaimi Jan 1991

Malaysia And The Law Of The Sea, Mohd Fadzil Shuhaimi

Marine Affairs Theses and Major Papers

The new legal regime of the oceans has brought many changes in the Malacca Strait. The most recent one in the enactment of the Malaysian Exclusive Economic Zone Act 1984 as corollary to its proclamation on the Exclusive Economic Zone in 1980. A year later, the Fisheries Act 1985 was enacted by Malaysia as a result of increasing needs to address new issues in fisheries protection and management in the Malaysian fisheries waters. The conclusion of the 1982 United Nations Convention on the Law of the Sea, among other things, has improvised the concept of transit passage in the straits …


Predation Risk And The Importance Of Cover For Juvenile Rainbow Trout In Lentic Systems, R. A. Tabor, Wayne A. Wurtsbaugh Jan 1991

Predation Risk And The Importance Of Cover For Juvenile Rainbow Trout In Lentic Systems, R. A. Tabor, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Juvenile rainbow trout Oncorhynchus mykiss stocked in midelevation reservoirs in Utah inhabit shallow nearshore areas and are vulnerable to predation from piscivorous fish and birds. We determined the use and importance of nearshore habitats by (1) measuring habitat selection by, prey availability to, and feeding of juvenile rainbow trout in two reservoirs with populations of predators, and (2) measuring survival and growth rates in the presence and absence of cover in a pond experiment where adult brown trout Salmo trutta were predators. In the reservoirs juvenile rainbow trout (60–120 mm standard length) were abundant in complex inshore habitats but avoided …


Long Term Management Measures For The Cockburn Sound Restricted Entry Fisheries., P. Millington Dec 1990

Long Term Management Measures For The Cockburn Sound Restricted Entry Fisheries., P. Millington

Fisheries Management Papers

The objective of this management plan is to introduce rules which will ensure there is a real reduction in professional fishing units and fishing effort in the medium to long term. This reduction should enable a small professional fishery to co-exist with the recreational sector, supply fresh fish to the metropolitan area, ensuring there is no proliferation of "shamateur fishing" and providing a supply of recreational angling bait.


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 …


State Of The Fisheries Report 1990, Fisheries Department Of Western Australia Dec 1990

State Of The Fisheries Report 1990, Fisheries Department Of Western Australia

Status Reports of the Fisheries and Aquatic Resources

The State of the Fisheries is published annually by the Fisheries Department as part of the statutory reporting process required under the Fisheries Act. This report covers developments and production in the State's fisheries up to the end of December 1990. Full details of the department's operations for this period are published separately in the department's annual reports for the financial years ending June 1990 and 1991. Figures provided in the tables are derived from catch returns completed by fishermen which are processed by the Australian Bureau of Statistics up to June 1990. Other information provided in the text comes …


The Effects Of Two Polycyclic Aromatic Hydrocarbons Benzo[A]Pyrene And Naphthalene On Reproductive Success Embryological Development Larval Physiology And Mortality Of The Mud Crab Rhithropanopeus Harisii (Gould), Gregory V. White Oct 1990

The Effects Of Two Polycyclic Aromatic Hydrocarbons Benzo[A]Pyrene And Naphthalene On Reproductive Success Embryological Development Larval Physiology And Mortality Of The Mud Crab Rhithropanopeus Harisii (Gould), Gregory V. White

OES Theses and Dissertations

Polycyclic aromatic hydrocarbons (PAHs) such as naphthalene (Nap) and benzo[a]pyrene (B[a]P) are common in the water column and sediments of estuarine and coastal areas. The mud crab Rhithropanopeus harrisii was exposed to varying concentrations of Nap or B[a]P to determine the effects on reproductive success, embryological development, larval physiology and mortality. Nap and B[a]P decreased hatching success and prolonged embryological development. Both pollutants produced high abnormality frequencies for egg exposed larvae. Molt frequency and respiratory rates of larvae from non-exposed eggs were more chronically affected by these pollutants than were egg exposed larvae. The EC50 concentrations were determined for …


Future Policy For Charter Fishing Operations In Western Australia., P. Millington Sep 1990

Future Policy For Charter Fishing Operations In Western Australia., P. Millington

Fisheries Management Papers

About 40 boats in Western Australia gain some of their income from taking recreational fishing parties out on charter. Half of these charter boats are also licensed commercial fishing boats. There are few Fisheries Department controls over charter boat fishing at present. However, with increasing tourism and leisure time, there are sound reasons for the Minister for fisheries to tighten up the controls over charter boat fishing to prevent over-exploitation in some areas or on particular stocks.


State Of The Fisheries Report 1989, Fisheries Department Of Western Australia Jun 1990

State Of The Fisheries Report 1989, Fisheries Department Of Western Australia

Status Reports of the Fisheries and Aquatic Resources

The State of the Fisheries is published annually by the Fisheries Department as part of the statutory reporting process required under the Fisheries Act. This report covers developments and production in the State's fisheries up to the end of December 1989. Full details of the department's operations for this period are published separately in the department's annual reports for the financial years ending June 1989 and 1990. Figures provided in the tables are derived from catch returns completed by fishermen which are processed by the Australian Bureau of Statistics. Other information provided in the text comes from research programs conducted …


Fisheries Research Report No. 89 - Relationships Among Partial And Whole Lengths And Weights For Western Australian Pink Snapper Chrysophrys Auratus (Sparidae), M. J. Moran, C. Burton Jun 1990

Fisheries Research Report No. 89 - Relationships Among Partial And Whole Lengths And Weights For Western Australian Pink Snapper Chrysophrys Auratus (Sparidae), M. J. Moran, C. Burton

Fisheries Research Reports

Pink snapper, Chrysophrysauratus (Sparidae) is one of the major commercial and recreational fish in Western Australian inshore waters. This report presents a number of equations and conversion factors for management and scientific study of the species. Equations to calculate total lengths from partial lengths will facilitate enforcement of minimum legal lengths when snapper are landed in a "head-off" condition. For fisheries science purposes, there are equations to convert among total length, standard length and length to caudal fork; and to convert lengths and weights of processed fish to whole lengths and weights. Length-weight relationships are presented and compared with those …


Fisheries Research Report No 88 - A Synopsis Of The Biology And The Exploitation Of The Australiasian Pilchard, Sardinops Neopilchardus (Steindachner) Part 1: Biology, W. J. Fletcher May 1990

Fisheries Research Report No 88 - A Synopsis Of The Biology And The Exploitation Of The Australiasian Pilchard, Sardinops Neopilchardus (Steindachner) Part 1: Biology, W. J. Fletcher

Fisheries Research Reports

There have been a large number of studies which relate to the biology and exploitation of the Australian pilchard, Sardinops neopilchardus. Much of the data, however, are located in journals which are hard to obtain, or in unpublished reports, and theses. With the increase in catch of pil­chards, particularly in Western Australia, a collation of all the available knowledge pertaining to pilchards in Australia and New Zealand was desired to help with the planning of future research into the Western Australian stocks of this species. This report contains all the information located on the biology of Sardinops neopilchardus, a companion …


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 …