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Articles 3001 - 3030 of 3147

Full-Text Articles in Animal Sciences

Effects Of Forage Availability On Voluntary Intake And Feeding Behavior Of Grazing Heifers, Anastasios S. Nastis May 1979

Effects Of Forage Availability On Voluntary Intake And Feeding Behavior Of Grazing Heifers, Anastasios S. Nastis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Forage intake by animals is an important factor in determining production of livestock products from rangelands. However, relatively little is known of effects of such forage variables as availability and distribution in space upon intake. Even less is known about how the grazing animal modifies its feeding tactics when confronted with diminishing or limited supplies of available forage and how such altered behavior may affect the animal's energetic cost for existence. Forage intake, body weight gain, grazing time and biting rate of Angus heifers was related to forage availability and plant height on semiarid crested wheatgrass rangeland during the late …


Interrelationships Between Benthic Macroinvertebrates And Habitat In A Mountain Stream, John M. Payne May 1979

Interrelationships Between Benthic Macroinvertebrates And Habitat In A Mountain Stream, John M. Payne

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A study to determine habitat differences of benthic macroinvertebrates was conducted on the upper Strawberry River, Utah. The investigation was part of a large scale project to determine minimum stream flow requirements for trout. The effects of time, habitat, depth and velocity on the distribution of benthic fauna were evaluated.

Samples of benthic invertebrates (146 total) were collected every 2 months at 8 stations on the river from November, 1975 through August, 1976. Representatives of 59 taxa were collected. Eight taxa comprised 90 percent of the mean annual community standing crop in numbers. Biomass was not dominated by any group …


Biology, Reproductive Potential And The Impact Of Fishing Pressure On The Bluegill Fishery Of Pelican Lake, Uintah County, Utah, Bob D. Burdick May 1979

Biology, Reproductive Potential And The Impact Of Fishing Pressure On The Bluegill Fishery Of Pelican Lake, Uintah County, Utah, Bob D. Burdick

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Certain aspects of the biology of two species of fish, bluegill (Lepomis macrochirus) and largemouth bass (Micropterus salmoides), and the assessment of fishing pressure upon the sport fishery of Pelican Lake, Uintah County, Utah, a 680 ha warmwater lake, were studied between April 1, 1976 and June 30, 1978. The growth rate of bluegills (sexes combined) was fairly rapid; the mean back-calculated total lengths from ages one through nine were 55, 112, 166, 194, 211, 229, 245, 256 and 259 mm. The growth of largemouth bass was 104, 194, 271, 316, 350, 405 and 416 mm …


Fisheries Report No. 37 - An Inventory Of The Marine Resources Of The Bunbury Marine Area And Geographe Bay, Michael H. Walker Jan 1979

Fisheries Report No. 37 - An Inventory Of The Marine Resources Of The Bunbury Marine Area And Geographe Bay, Michael H. Walker

Fisheries Research Reports

The marine resources of the Geographe Bay/Bunbury marine area were investigated using a variety of fishing gear i.e. set lines, set nets, trawls, ring nets, beach seines, hand lines, trolling lines, traps and light attraction at night. All the ftsh species caught were documented as to breeding state and food habits.

Commercial species encountered as adults during fishing operations were: bronze whaler, whiskery and gummy sharks, Westralian jewfish, Australian herring, skippy, flathead, oriental bonito, blue and sandy sprat, pilchard, mulloway, whiting, yellowtail scad, flounder, and leatherjacket and as juveniles were: skippy, yellowtail scad, tailor, southern sea garfish, pilchard, blue and …


Fisheries Report No 33 - The Western Rock Lobster Fishery 1975 - 1976, G. R. Morgan, E H. Barker Jan 1979

Fisheries Report No 33 - The Western Rock Lobster Fishery 1975 - 1976, G. R. Morgan, E H. Barker

Fisheries Research Reports

iTshe fishery for the western rock lobster Panultrus ecygnus one of the most important single fisheries in Australia and an important export earner for the State. The fishery is governed by a complex set of regulations which have been reviewed by Bowen (1971) and which are designed to limit the total effort to acceptable levels and to enforce a legal minimum size. It is thus important to constantly monitor the state of the fishery both to ensure that the effort is remaining within the accepted limits and that the regulations are adequately performing their function of maintaining reasonably stable catches. …


Fisheries Report No 34 - The Status Of The Salt-Water Crocodile In The Glenelg, Prince Regent And Ord River Systems, Kimberley, Western Australia, A. A. Burbidge, H. Messel Jan 1979

Fisheries Report No 34 - The Status Of The Salt-Water Crocodile In The Glenelg, Prince Regent And Ord River Systems, Kimberley, Western Australia, A. A. Burbidge, H. Messel

Fisheries Research Reports

Counts were made of Salt-water Crocodiles (Crocodylus porosus) in the estuarine portions of the Glenelg, Prince Regent and Ord River systems of the Kimberley Division, Western Australia. During the survey 581 crocodiles were seen, including 143 hatchlings. The number of non-hatchling crocodiles in present the Glenelg system is estimated to be 200 to 259, in the Prince Regent 190 to 246 and in the Ord 235 to 306 (95% confidence limits).

The number of non-hatchling crocodiles present in the six Kimberley river systems now counted is estimated to be between 957 and 1243 (95% confidence limits) and we believe that …


Fisheries Report No 38 - The Shark Bay Prawn Fishery (1970 - 1976), J. W. Penn, R. W. Stalker Jan 1979

Fisheries Report No 38 - The Shark Bay Prawn Fishery (1970 - 1976), J. W. Penn, R. W. Stalker

Fisheries Research Reports

The existence of prawn stocks in Shark Bay, Western Australia, has been known since 1904 when the sailing ketch "Rip" on charter to the Western Australian Government, trawled large quantities of prawns from the area between Bernier Island and the mainland, Gale (1905). Although the Fisheries research vessel "Lancelin" trawled potentially commercial quantities of prawns from Shark Bay in the early 1950's, it was not until 1962 that a regular fishery was begun.

Today the prawn stocks of Shark Bay support Western Australia's largest and most consistent prawn fishery, having an annual production currently exceeding 2 000 tonnes. The catch …


Erosion Risks With High Stocking Rates At Kojonup Trial, Department Of Agriculture, Western Australia Jan 1979

Erosion Risks With High Stocking Rates At Kojonup Trial, Department Of Agriculture, Western Australia

Journal of the Department of Agriculture, Western Australia, Series 4

A pasture grazing trial at Kojonup dramatically illustrated the effects of Cyclone Alby. Severe erosion was evident on the heavily stocked plots while the more lightly stocked plots showed little damage.


Niobrara-Missouri River Fishery Investigations, Larry W. Hesse, Gene Zeurlein, Roger Vancil, Leonard Koziol, Brad Newcomb, Leigh Ann Retelsdorf Jan 1979

Niobrara-Missouri River Fishery Investigations, Larry W. Hesse, Gene Zeurlein, Roger Vancil, Leonard Koziol, Brad Newcomb, Leigh Ann Retelsdorf

Nebraska Game and Parks Commission: Publications

The Niobrara River heads in the table lands of eastern Wyoming and flows 786 kilometers (km) eastward across Nebraska joining the Missouri River near the town of Niobrara, Nebraska. The Niobrara is the largest Missouri River tributary between the last two mainstem impoundments (Lake Francis Case and Lewis and Clark Lake). Fish movement up the Niobrara is prevented by Nebraska Public Power District's (NPPD's) Spencer Hydroelectric Dam, 63.3 km upstream from the river mouth. The lower reach of the river is turbid and carries a considerable load of sand, silt, and organic debris into the Missouri River. The mean annual …


Nebraska Rainbow Trout, Nebraska Game And Parks, G. Zeurlein, L. Hesse, J. Seeb, L. Wishard Jan 1979

Nebraska Rainbow Trout, Nebraska Game And Parks, G. Zeurlein, L. Hesse, J. Seeb, L. Wishard

Nebraska Game and Parks Commission: Publications

Chapter 1 Lethal and Preferred Temperatures of Lake McConaughy Rainbow Trout Versus Domestic Strain Rainbow Trout By R. Vancil, G. Zuerlein and L. Hesse

Chapter 2 A Nitrifying Filter-Cooling Condenser System for Total Water Re-use in Cold-Water Fish Holding or Rearing Applications By L. Hesse, G. Zuerlein and R. Vancil

Chapter 3 Biochemical Genetic Analysis of Two Strains of Nebraska Rainbow Trout By J. Seeb and L. Wishard

The self-sustaining rainbow trout population living in Lake Mcconaughy and the North Platte River tributaries is unique to the Great Plains region. The population spends most of its adult life in the …


Saving The State From Rabbits, Department Of Agriculture, Western Australia Jan 1979

Saving The State From Rabbits, Department Of Agriculture, Western Australia

Journal of the Department of Agriculture, Western Australia, Series 4

A thoughtful look at the rise and fall of rabbit populations in Western Astralia and the work done to achive the current levels.


Potential Use Of Hydroelectric Facilities For Manipulating The Fertility Of Lake Mead, Larry J. Paulson, John R. Baker, James E. Deacon Jan 1979

Potential Use Of Hydroelectric Facilities For Manipulating The Fertility Of Lake Mead, Larry J. Paulson, John R. Baker, James E. Deacon

Publications (WR)

Analysis of historical nutrient data for Lake Mead indicates that the fertility of the reservoir has decreased which may be the cause for a corresponding decline in the largemouth bass population. However, it appears that fertility can be manipulated by altering the operation of the dam. The depletion of nutrients in the euphotic zone by phytoplankton and subsequent accumulation in the hypolimnion during summer and fall provide a natural nutrient gradient from which water of varying fertility can be drawn for discharge. This combined with alterations in the depth or seasonal pattern of discharge can possibly be used to enhance …


The Maine Coast : Issues Considered, Maine Coastal Program Oct 1978

The Maine Coast : Issues Considered, Maine Coastal Program

Maine Collection

The Maine Coast : Issues Considered - A Report to the Governor by his Advisory Committee on Coastal Development and Conservation

Maine Coastal Program, Maine State Planning Office

Augusta, Maine (31 October 1978)

Contents: Introduction / Summary of Committee Recommendations / Fisheries / Port Development / Heavy Industry Siting / Travel and Tourism / Cumulative Impact of Development / Natural Resource Information Transfer


State Of The Fisheries Report 1977, Department Of Fisheries And Wildlife, Western Australia Sep 1978

State Of The Fisheries Report 1977, Department Of Fisheries And Wildlife, Western Australia

Status Reports of the Fisheries and Aquatic Resources

The total value of the fisheries of Western Australia is the highest of any of the States, and the Western Australian rock lobster fishery is the most valuable single fishery in Australia.


The Effect Of Selenium On The Toxicity Of Methyl Mercury In Medaka Embryos, Peter H. Krauth May 1978

The Effect Of Selenium On The Toxicity Of Methyl Mercury In Medaka Embryos, Peter H. Krauth

All-Inclusive List of Electronic Theses and Dissertations

The purpose of this research was to investigate the effect of selenium upon methyl mercury poisoning in Medaka fish (Oryzias latipes) embryos. Selenium has been shown to provide a protective mechanism against mercury poisoning in some adult animals. Three experiments were done. In the first, selenium and methyl mercury were put directly in the growing medium of the eggs. In the second experiment, selenium was included in the diet of the parent fish. In the third part, methyl mercury exposure was delayed three days. The results of the first experiment were quite dramatic and showed a significant difference when selenium …


A Discriminant Function Model Of Gray-Headed Junco Habitat, Andrew R. Grainger May 1978

A Discriminant Function Model Of Gray-Headed Junco Habitat, Andrew R. Grainger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This paper presents a description of gray-headed junco habitat in the form of a model based on discriminant function analysis. Junco nests were found by searching randomly located grids on a 7.8 km2 study area in central Utah. Vegetation data was gathered on 500 m2 circular plots surrounding nests and contrasted with similar data from searched grids where nests were not found. The model explains 28 percent of the between-groups variance and correctly classifies 68 percent of the plots.

Plant cover types are good predictors of areas where gray-headed juncos nest, while plant community type descriptions do not …


Physiological Response To Hooking Stress In Largemouth Bass (Micropterus Salmoides), A. Wayne Gustaveson May 1978

Physiological Response To Hooking Stress In Largemouth Bass (Micropterus Salmoides), A. Wayne Gustaveson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recent concern about large initial and delayed mortalities resulting from tournament angling for largemouth bass has indicated that it would be desirable to further evaluate the fate of fish that are released after being captured by angling. This study was designed to evaluate sublethal physiological disruptions caused by hooking stress after largemouth bass were played under standardized conditions (0-5 minutes) and to estimate the time needed for recovery of the homeostatic mechanisms (to 72 hours). Blood lactate was used as a measure of metabolic fatigue; plasma osmolality and chloride measurements were used to evaluate osmoregulatory disturbances and gill ion-exchange; and …


Population Dynamics And Net Production Of Brown Trout (Salmo Trutta) In Two Areas Of A High Gradient Mountain Stream, Jeffrey C. Gosse May 1978

Population Dynamics And Net Production Of Brown Trout (Salmo Trutta) In Two Areas Of A High Gradient Mountain Stream, Jeffrey C. Gosse

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Estimates of the brown trout (Salmo trutta) population were made in two areas of the Blacksmith Fork River, Cache County, Utah, from June 1972 to June 1973. Additional data were obtained on movement, growth, mortality, biomass, production, and yield.

Population density was highly variable in the area where habitat alterations had occurred, but was relatively uniform where the habitat was undisturbed. The brown trout exhibited little movement except during spawning season. Instantaneous growth and mortality rates are provided for each age group.

Mean annual biomass in the two areas was 12.0 and 10.2 grams per square meter and …


Adaptive Significance Of Lactate Dehydrogenase B2 Isozymes In Rainbow Trout, Salmo Gairdneri And A Biochemical Genetic Comparison Of Cutthroat Trout (Salmo Clarki) Populations, Gerald Thomas Klar May 1978

Adaptive Significance Of Lactate Dehydrogenase B2 Isozymes In Rainbow Trout, Salmo Gairdneri And A Biochemical Genetic Comparison Of Cutthroat Trout (Salmo Clarki) Populations, Gerald Thomas Klar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rainbow trout lactate dehydrogenase (LDH) B2' B2' , B2' B2" and B2" B2" phenotypes were tested under a variety of conditions for swimming endurance, oxygen consumption rates, and blood pH, pO2, and lactate. The B2" B2" phenotype exhibited a lower swimming endurance, under a limited oxygen supply, than the B2' B2' and B2' B2" phenotypes. Blood pH at fatigue did not differ among the LOH phenotypes that swam under low oxygen conditions (2 mg/1). …


Producing 20-Month Old Beef Steers Off Annual Pasture, K D. Greathead, D. J. Barker, W. J. Ryan Jan 1978

Producing 20-Month Old Beef Steers Off Annual Pasture, K D. Greathead, D. J. Barker, W. J. Ryan

Journal of the Department of Agriculture, Western Australia, Series 4

A recent Mt Barker experiment compared two systems of fodder conservation with continuous grazing, using two types of steers, at three stocking rates. Year-round performance, carcass composition, and resulting costs and returns per hectare were assessed.

Production per hectare was greatest from crossbred steers at the intermediate stocking rate with either type of fodder conservation.


Fisheries Report No 35 - Fish And Exploited Crustaceans Of The Swan-Canning Estuary, R C.J. Lenanton Jan 1978

Fisheries Report No 35 - Fish And Exploited Crustaceans Of The Swan-Canning Estuary, R C.J. Lenanton

Fisheries Research Reports

Fishes of the Swan-Canning estuarine system are typical of those found in other lower west coast estuarine systems of Western Australia. Species representing three families of elasmobranchs, several of which are commercially important, twenty families of teleosts, and two families of crustaceans (Table 1) commonly occur in this estuarine system. The many other species which occur less commonly in the Swan- Canning estuary are mostly members of the additional families listed in Table l.

The information contained in this document was made available for use by the authors of the following two publications : -

Forbes and Fitzkardinge (1977) Swan …


Fisheries Report No 32 - The Wildlife Of The Proposed Wandana Nature Reserve, Near Yuna, Western Australia, A. A. Burbidge, P. J. Fuller, A. Mccusker Jan 1978

Fisheries Report No 32 - The Wildlife Of The Proposed Wandana Nature Reserve, Near Yuna, Western Australia, A. A. Burbidge, P. J. Fuller, A. Mccusker

Fisheries Research Reports

Following a Cabinet endorsed recommendation by the Environmental Protection Authority in 1976 an area of vacant Crown land (the Wandana Area) north-east of Yuna, Western Australia, was examined during March and September, 1977.

The geology, soils and vegetation of the area are described and annotated lists of mammals, birds, reptiles and amphibians are presented. The area lies near or on the boundary of the South- Western and Eremaean Botanical Provinces and vegetation formations typical of both occur. The vertebrate fauna is a mixture of South-Western and Eyrean species and is especially rich in reptiles, 41 species being recorded. Comparisons between …


Fisheries Report No 36 - Utilization Of The Bunbury And Geographe Bay Marine Resource By Professional And Amateur Fishermen, Michael H. Walker Jan 1978

Fisheries Report No 36 - Utilization Of The Bunbury And Geographe Bay Marine Resource By Professional And Amateur Fishermen, Michael H. Walker

Fisheries Research Reports

Utilization of the Bunbury and Geographe Bay marine resource by professional and amateur fishermen was investigated by personal interview, distribution and analysis of research log sheets, and examination of commercial statistics for the area, published by the Australian Bureau of Statistics.

Total professional production for the years 1966/67 - 1974/75 for Geographe Bay varied between 225517 and 1218049 Kg (mean 497175) with a mean annual value to fishermen of $427708. Production for the Bunbury marine area varied between 157666 and 333810 Kg (mean 226526) with a mean value to fishermen of $311008. For the 1975/76 season the total production was …


Fish Of Lake Mead And Lake Mohave, Robert C. Allan, Dennis L. Roden Jan 1978

Fish Of Lake Mead And Lake Mohave, Robert C. Allan, Dennis L. Roden

Publications (WR)

This publication offers an in-depth study of the fish and other organisms that live in Lakes Mead and Mohave. The history and background of the two lakes is offered, as well as information about diseases, parasites, and unusual fish occurrences. Food sources, predation and competition are also discussed.


Fisheries Report No 30 - The Wildlife Of The Proposed Karroun Hill Nature Reserve, Western Australia, W. K. Youngson, N. L. Mckenzie Oct 1977

Fisheries Report No 30 - The Wildlife Of The Proposed Karroun Hill Nature Reserve, Western Australia, W. K. Youngson, N. L. Mckenzie

Fisheries Research Reports

Plants and vertebrate animals were recorded from a proposed 300 000 ha nature reserve centred on Karroun Hill in the goldfields of Western Australia (30°03'S; 118°02'E).

Plant communities are described in terms of their structurally important species and related to local physiography.

Fifteen native mammal species, sixty-four bird species, twenty-four reptile species and one amphibian were recorded. Annotated lists are presented. The wildlife reflects the transitional nature of the Coolgardie Botanical District. Both Eremean and South Western Province species were recorded.


State Of The Fisheries Report 1976, Department Of Fisheries And Wildlife, Western Australia Aug 1977

State Of The Fisheries Report 1976, Department Of Fisheries And Wildlife, Western Australia

Status Reports of the Fisheries and Aquatic Resources

The total value of the fisheries of Western Australia is the highest of any of the States, and the Western Australian rock lobster fishery is the most valuable single fishery in Australia.


Rodent Density And Species Composition In The Snake River Birds Of Prey Natural Area, Idaho, Jon R. Montan Jr. May 1977

Rodent Density And Species Composition In The Snake River Birds Of Prey Natural Area, Idaho, Jon R. Montan Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rodent densities were estimated in the major vegetation types of the Snake River Birds of Prey Natural Area in 1975 and 1976 by a combination of live-trapping and kill-trapping. Only deer mice (Peromyscus maniculatus) were numerous enough to permit reliable density estimates. Relative densities of other rodent species were indicated by kill-trap capture rates. Densities of deer mice correlated well (r = 0.99) with kill-trap capture rates. The use of kill-trapping in place of live-trapping in 1976 permitted extensive sampling throughout the 1930 km2 study area. Differences were found among the major vegetation and land-use types in …


Biological Manipulation Of Blackbrush (Coleogyne Ramosissima Torr.) By Browsing With Goats, Frederick D. Provenza May 1977

Biological Manipulation Of Blackbrush (Coleogyne Ramosissima Torr.) By Browsing With Goats, Frederick D. Provenza

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to provide data on responses of Angora goats and blackbrush (Coleogyne ramosissima) to a biological manipulation program. Blackbrush utilization levels averaged 30, 16, and 6 percent (545, 367, and 147 kg per hectare) for the heavily, moderately, and lightly browsed pastures, respectively; removal rates of 77, 38, and 19 percent (1164, 582, and 291 kg per hectare) were projected.

Statistically significant differences in body weight loss (P=0.052) were noted for goats browsing in different replications. Goats lost an average of 14 and 19 percent of body weight in replications one and two, …


Fisheries Report No 28 - The Western Rock Lobster Fishery 1974-1975, G. R. Morgan, E H. Barker Jan 1977

Fisheries Report No 28 - The Western Rock Lobster Fishery 1974-1975, G. R. Morgan, E H. Barker

Fisheries Research Reports

The fishery for the western rock lobster Panultrus eygnus is one of the most important single fisheries in Australia and an important export earner for the State. The fishery is governed by a complex set of regulations which have been reviewed by Bowen (1971) and which are designed to limit the total effort to acceptable levels and to enforce a legal minimum size. It is thus important to constantly monitor the state of the fishery both to ensure that the effort is remaining within the accepted limits and that the regulations are adequately performing their function of maintaining reasonably stable …


Fisheries Report No 20 - Trawl Caught Fish And Crustaceans From Cockburn Sound, J. W. Penn Jan 1977

Fisheries Report No 20 - Trawl Caught Fish And Crustaceans From Cockburn Sound, J. W. Penn

Fisheries Research Reports

Cockburn Sound is one of the few sheltered embayments near the Perth metropolitan area and as such has been subjected to increasing usage by both the general public and industry. Historically the Sound has been a major commercial fishing area from which much of the fresh fish for the metropolitan area has been caught. More recently, as well as providing a significant commercial catch, a major sport fishery has developed in the area.

The first commercial trawling operations in Cockburn Sound were undertaken in the early part of this century when horses were used to tow small nets on the …