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An Analysis Of Stock Densities And Harvest Of The Cutthroat Trout Of The Snake River, Teton County, Wyoming, John W. Kiefling May 1972

An Analysis Of Stock Densities And Harvest Of The Cutthroat Trout Of The Snake River, Teton County, Wyoming, John W. Kiefling

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An intensive creel census and marking program was conducted in 1969 and 1970 to make possible population estimates and estimates of harvest of cutthroat trout in the Snake River in Teton County, Wyoming. Stock density determinations made in one of the five study areas provided an estimate of 400 and 992 cutthroat trout, eight inches or more in length, per mile of stream in 1969 and 1970 respectively.

Harvest data provide an estimate of 5,207 and 5,903 cutthroat trout harvested in 1969 and 1970 respectively. The harvest estimates obtained in this study are not comparable to those made in 1967 …


State Of The Fisheries Report 1970/1971, Department Of Fisheries And Fauna, Western Australia May 1972

State Of The Fisheries Report 1970/1971, Department Of Fisheries And Fauna, 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.


Reproduction And Hematology Of The Cache Elk Herd, Thomas B. Follis May 1972

Reproduction And Hematology Of The Cache Elk Herd, Thomas B. Follis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The initial three years of a 10-year reproductive study of elk involved three major phases. A fourth was added because of convenience. Objective 1 was to ascertain pregnancy rates in yearling and mature elk by rectal palpation, associate these rates with subsequent fall cow/calf ratios, and to test concurrently an ultrasonic fetal heart detector. Rectally observed anatomical changes in gravid uteri of cattle were directly applicable to elk. Ultrasonic detections of pregnancies in elk and deer were unsuccessful.

Pregnancy rates in the 1969-70 winter of 100 and 0 percent, respectively, for 19 adult and five yearling elk were associated with …


Population Biology Of The Black-Tailed Jackrabbit (Lepus Californicus) In Northern Utah, L. Charles Stoddart May 1972

Population Biology Of The Black-Tailed Jackrabbit (Lepus Californicus) In Northern Utah, L. Charles Stoddart

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Population biology of the black-tailed jackrabbit population on a 250-square-mile area in Curlew Valley, northern Utah, was studied from 1962-70. During this period the fall population density index increased from 40.0 in 1962, to 60.6 in 1963, decreased progressively to a low of 21.2 in 1967, then increased the following 3 years to a high of 185.0 in 1970.

Breeding was synchronous with four conception periods each year; in some years a fifth conception period was evident. The first conception period occurred about the last half of January; other periods followed at 40-day intervals indicating a 40-day gestation period and …


Some Aspects Of Conditioning Behavior In Rainbow Trout, Salmo Gairdneri, Reed E. Harris May 1972

Some Aspects Of Conditioning Behavior In Rainbow Trout, Salmo Gairdneri, Reed E. Harris

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Effects of exercise, social facilitation, and delayed conditioning after vi exercise on the learning behavior of 5 to 6-inch rainbow trout, Salmo gairdneri, was measured in a conditioned avoidance response apparatus. The conditioning schedule contained an intertrial interval between alternate presentations of conditioned (light) and unconditioned (shock) stimuli. This randomization eliminated learning losses found in a previous study. Mean percentage avoidance, the measurement of learning, did not decrease significantly during conditioning trials. Exercised fish learned avoidance better than did non-exercised fish. Mean percentage avoidance for fish exercised at 0.5 ft/sec was 66.3; at 1.0 ft/ sec, 1.5 ft/sec, and …


Methodological And Validation Study Of Seed Reserves In Desert Soils, David W. Goodall, Stuart Childs, Herman Wiebe Apr 1972

Methodological And Validation Study Of Seed Reserves In Desert Soils, David W. Goodall, Stuart Childs, Herman Wiebe

Memorandum

The development of a method for separating seeds from desert soils, and enumerating them, is described.

In the Great Basin desert, species differed greatly in their depth distribution, some having a peak at or just below the surface, while others were still abundant below 5 cm. Much higher seed densities were found beneath the canopies of shrubs and of tussock grasses than in the inter-spaces; no consistent differences were found, however, associated with the species of the canopy plant, or with distance from its center.

Tentative estimates are given of the seed population in the four validation sites in Curlew …


What’S Ahead In Predator Management, Maynard W. Cummings Mar 1972

What’S Ahead In Predator Management, Maynard W. Cummings

Vertebrate Pest Conference Proceedings: 5th (1972)

Editors note: Because of the great need for exchange of information concerning predator management, I have requested and received permission from the author to include in the Vertebrate Pest Conference Proceedings this paper presented at the Predator Ecology Symposium held in Orland, California, March 1, 1972.

There may not be many things about predators that everyone here agrees upon, but I do believe you all are certain that major changes are about to be made in their management. You all are aware of two recent proclamations of change, the President's Executive Order No. 11643 of February 8, 1972, and the …


Conference Participants, Fifth Vertebrate Pest Conference (1972) Mar 1972

Conference Participants, Fifth Vertebrate Pest Conference (1972)

Vertebrate Pest Conference Proceedings: 5th (1972)

The Fifth Vertebrate Pest Conference drew a registered attendance of 239 with an estimated additional 50-75 persons who attended portions of the conference but did not register. As in past conferences, the attendance was made up of individuals having varying interests in vertebrate pest problems from twenty two states plus the District of Columbia. Participants from Canada, Denmark, England, Germany, India and New Zealand contributed greatly to the success of the conference and provided further exchange of information on an international level.


Tolerance Shown By Rattus Rattus To An Anticoagulant Rodenticide, P. J. Deoras, G. C. Chaturvedi, N. E. Vad, D. M. Renapurkar Mar 1972

Tolerance Shown By Rattus Rattus To An Anticoagulant Rodenticide, P. J. Deoras, G. C. Chaturvedi, N. E. Vad, D. M. Renapurkar

Vertebrate Pest Conference Proceedings: 5th (1972)

Apart from using 0.005% concentration, the recommended field dose of 0.025% of the anticoagulant is used along with an alternate food for individual rats for a varying number of days. Those that had survived were taken as tolerant, provided they showed an mg/kg intake beyond the tolerance limit, survived a six days of feeding, exhibited bait-shyness and did not exhibit hemorrhage after death. In determining the criteria for tolerance to an anticoagulant by a rat, one should take into account four composite factors. These are, six days of even 0.025% feeding, bait-shyness when alternate food is given, higher mg/kg intake …


Contents, Committees, And Frontmatter Mar 1972

Contents, Committees, And Frontmatter

Vertebrate Pest Conference Proceedings: 5th (1972)

No abstract provided.


Status And Control Of Nutria In California, Frank Schitoskey Jr., James Evans, G. Keith Lavoie Mar 1972

Status And Control Of Nutria In California, Frank Schitoskey Jr., James Evans, G. Keith Lavoie

Vertebrate Pest Conference Proceedings: 5th (1972)

Although feral nutria (Myocastor coypus) have been present in California since the mid-1940's, they are quite scarce and at present are causing little or no agricultural damage. Present state regulations and pest detection activities will probably prevent them from becoming a serious economic pest. Should control ever become necessary, studies in other areas indicate that shooting, trapping, and baiting with zinc phosphide should be effective.


Muskrats In Central Europe And Their Control, Kurt Becker Mar 1972

Muskrats In Central Europe And Their Control, Kurt Becker

Vertebrate Pest Conference Proceedings: 5th (1972)

An account of the introduction of muskrats into Europe and their spread over the countries of Europe is presented. The reasons why the animal should be controlled are discussed. Legal regulations often do not keep up with the requirements and economic and political circumstances and frequently have encouraged the spread of muskrats. The use of traps alone does not solve the problem of their control. Therefore research is looking for suitable poisons and a good practice to apply them. At present this question cannot be answered satisfactorily.


The Need Of Surface Sprays For The Control Of Microtine Rodents, Mogens Lund Mar 1972

The Need Of Surface Sprays For The Control Of Microtine Rodents, Mogens Lund

Vertebrate Pest Conference Proceedings: 5th (1972)

Four Microtine species, the field vole (Microtus agrestis), the continental vole (Microtus arvalis), the water vole (Arvicola terrestris) arid the bank vole (Clethrionomys glareolus) are the most harmful rodents in forests, fields, orchards and gardens in Northern and Central Europe. Except for the latter they are all herbivorous, their food consisting to a very low degree of seeds and grain. As a consequence dry poison baits are not well accepted most of the year. The only economic and effective control method until now has been surface spraying with the chlorinated hydrocarbons endrin and toxaphene. As these chemicals are now black-listed …


Protecting Coniferous Seeds From Rodents, Andrew Radvanyi Mar 1972

Protecting Coniferous Seeds From Rodents, Andrew Radvanyi

Vertebrate Pest Conference Proceedings: 5th (1972)

For almost a half century now repeated failures in direct seeding operations on cutover forest lands in North America had been largely blamed on the unproven destruction of the seed supply by small mammals. In 1960, the Canadian Wildlife Service undertook a research project to ascertain the possible fate of white spruce seeds placed into the natural environment and the influence which small mammal populations may have upon such a seed supply. By equipping each seed with a microscopic radio-transmitter (radio isotopes), the seeds could be left in the field for up to one year and then recovered intact or …


Methodology For Measuring Taste And Odor Preference Of Rodents, R. D. Thompson, S. A. Shumake, R. W. Bullard Mar 1972

Methodology For Measuring Taste And Odor Preference Of Rodents, R. D. Thompson, S. A. Shumake, R. W. Bullard

Vertebrate Pest Conference Proceedings: 5th (1972)

Taste enhancers and olfactory attractants are needed to improve bait acceptance for rodent control, but most methods for evaluating preference for taste and odor stimuli are not suitable for screening large numbers of such compounds. This paper describes two automated preference testers designed for this purpose. The taste preference apparatus is based on the principle of the brief-exposure, foods-together technique, whereby the animal briefly samples each food alone, in alternate sequence, before the two foods are presented together, in alternate positions. The odor preference tester is based on an open-field maze, whereby the test animal samples each of four odor …


Barrier Fencing In Wildlife Management, William D. Fitzwater Mar 1972

Barrier Fencing In Wildlife Management, William D. Fitzwater

Vertebrate Pest Conference Proceedings: 5th (1972)

Barrier fences have been used to control animal and human depredations since ancient times. They have exerted considerable influence upon the culture of the "protected" areas even though protection was rarely complete. The following materials have been used in construction of fences: earth, vegetative materials, wire, electric shock, and synthetic materials. Fence designs must consider the size, strength, intelligence and/or instinct, and physical agility of the species to be repelled as well as the attraction of the crop or area for potential depredators. Against deer, the 8-foot upright, vertical overhanging, outrigger and sloping fences are more successful than electric fences. …


A Preference-Testing System For Evaluating Repellents For Black-Tailed Deer, Dan L. Campbell, Roger W. Bullard Mar 1972

A Preference-Testing System For Evaluating Repellents For Black-Tailed Deer, Dan L. Campbell, Roger W. Bullard

Vertebrate Pest Conference Proceedings: 5th (1972)

In a program to evaluate repellents for protecting Douglas-fir(Pseudotsuga menziesii) seedlings from browsing by black-tailed deer (Odocoileus hemionus columbianus), a preference-testing system was developed to supplement preliminary pen tests. The system uses an apparatus that presents individual test deer with a choice between two foods (usually feed pellets treated with a candidate repellent or a marginally palatable standard). The two foods are presented, in alternating positions, only long enough for the deer to make a choice; results are recorded in terms of percent choices made for the candidate repellents, or percent consumption. Tests thus far with a number of candidate …


Good Practice Statements−Developing Guidelines For The Safe And Efficient Use Of Pesticides, Harold S. Stein Jr. Mar 1972

Good Practice Statements−Developing Guidelines For The Safe And Efficient Use Of Pesticides, Harold S. Stein Jr.

Vertebrate Pest Conference Proceedings: 5th (1972)

Because pest control, vertebrate and invertebrate, is an applied science, a disciplined technology is mandatory. The National Pest Control Association, through its technical committees, is developing guidelines for the safe and efficient use of pesticides and for the execution of specific forms of pest control. These guidelines known as "Good Practice Statements" not only reveal a methodology utilizing the cooperative efforts and experiences of commercial pest control operators, representatives of the scientific community, and specialists from pertinent governmental regulatory agencies, but in them-selves as physical documents add to the total expertise of everyone connected with the problems and responsibilities of …


The Oregon Ground Squirrel In Northeastern California; Its Adaptation To A Changing Agricultural Environment, Loring White Mar 1972

The Oregon Ground Squirrel In Northeastern California; Its Adaptation To A Changing Agricultural Environment, Loring White

Vertebrate Pest Conference Proceedings: 5th (1972)

As early as 1918, populations of the Oregon ground squirrel [Citellus oregonus (Merriam)] were reported to be increasing in northeastern California, presumably because of “the extensive clearing of the sagebrush and seeding of these clearings to grain and hay." Populations of this locally important field rodent have continued to increase since that time with the further development of agriculture. Observations of the author during the past quarter of a century indicate that ground squirrels in the most intensively farmed areas are changing their habits; and may be evolving into an ecotype markedly dissimilar to that which existed in the pristine …


Zinc Phosphide−A New Look At An Old Rodenticide For Field Rodents, Glenn A. Hood Mar 1972

Zinc Phosphide−A New Look At An Old Rodenticide For Field Rodents, Glenn A. Hood

Vertebrate Pest Conference Proceedings: 5th (1972)

Of the many toxicants tested to control field rodents, compound 1080 (sodium monof1uoroacetate), strychnine alkaloid, and zinc phosphide are the only effective single-dose rodenticides currently available. Considering the federal requirements for use in food and feed crops, zinc phosphide is the toxicant most likely to be registered for field rodent control. It is generally well accepted by rodents, is relatively safe for nontarget species, and does not seriously contaminate the environment. It is already registered, with an established tolerance, for use in one food crop (Hawaiian sugarcane). The Bureau of Sport Fisheries and Wildlife is conducting research, some in cooperation …


Vertebrate Pests In New Zealand; Research And Control, J. Andrew Peters Mar 1972

Vertebrate Pests In New Zealand; Research And Control, J. Andrew Peters

Vertebrate Pest Conference Proceedings: 5th (1972)

New Zealand has been considered a classic among the world's natural laboratories where free-roaming wild mammals demand, and obtain, a rather overwhelming national attention. The enormous devastation by erosion processes is the consequence of intentionally introducing exotic species of mammals, for food, for sport and for fur. By its isolation in the Pacific, the flora of New Zealand evolved in the absence of a grazing and browsing fauna. There were no native mammals, save for the seals and two species of bats. The land has been the home of a most diverse fauna of flightless birds -kiwis, the giant moa, …


Experimental Population Suppression Of Richardson's Ground Squirrels (Spermophilus Richardsonii) In Alberta, Dale E. Alsager, Robert Yaremko Mar 1972

Experimental Population Suppression Of Richardson's Ground Squirrels (Spermophilus Richardsonii) In Alberta, Dale E. Alsager, Robert Yaremko

Vertebrate Pest Conference Proceedings: 5th (1972)

Richardson's Ground Squirrel is one of the most economically harmful rodents in east central Alberta. In an effort to develop an effective, safe, economical and practical method of long-term population control over large areas, experimental field testing was begun in 1970 to evaluate a variety of potential control techniques. Although tests with a machine bait applicator proved unsuccessful due to the unique soil structure, its potential in other areas of the province is discussed. Use of portable baiting stations is limited by the manufacturing and maintenance costs as well as the limited attractabi1ity of the stations. Attractabi1ity of the stations …


The Extension Trapper System In Kansas, F. Robert Henderson Mar 1972

The Extension Trapper System In Kansas, F. Robert Henderson

Vertebrate Pest Conference Proceedings: 5th (1972)

Kansas is unique because it is the only state that has an organized state-wide program that is administered through the State Cooperative Extension Service and where that program is the only form of a governmental predator program in the state. Missouri and the eastern part of South Dakota have Extension Trapper Systems administered through the state wildlife conservation departments. These states also pay bounties on predatory animals. Kansas does not. To fully appreciate the Kansas system, it is important to understand the agency that administers the program. Let us briefly review the Cooperative Extension Service, Created by the Smith-Lever Act …


Factors Relating To Alarm Stimuli In Bird Control, Gordon W. Boudreau Mar 1972

Factors Relating To Alarm Stimuli In Bird Control, Gordon W. Boudreau

Vertebrate Pest Conference Proceedings: 5th (1972)

I'm sure all of you have often heard of bird control methods which were successful in one place and failures elsewhere. Perhaps you have experienced these results yourself. Quite often, bird control apparatus or concepts are condemned as failures when actually other factors are responsible. Today, I shall explain some of the reasons these discrepancies occur. My observations, over a period of 15 years, reveal that birds' responses to alarm stimuli varies with environmental conditions, clocktime, physiological requirements, social structure, species, and other factors. All of the observations reported herein were made under natural conditions while researching methods to reduce …


Avian Thermoregulation And Its Significance In Starling Control, Robert G. Schwab, Vincent F. Schafer Mar 1972

Avian Thermoregulation And Its Significance In Starling Control, Robert G. Schwab, Vincent F. Schafer

Vertebrate Pest Conference Proceedings: 5th (1972)

The ability of birds and mammals to maintain a relatively stable internal body temperature while under a considerable range of ambient environmental temperatures results in distinct ecological and physiological advantages. A constant body temperature facili-tates the activity of homeothermic (warm-blooded) animals in cold environments because the many temperature-dependent physiological and biochemical processes of the body are un-impeded. Conversely, poikilothermic (cold-blooded) animals lack the ability for precise thermoregulation and can function at top physiological efficiency only when ambient environmental temperatures are within a rather narrow optimum range. Homeothermia is accomplished by a system of physiological feed-back mechanisms which maintain a thermal …


Efficacy Testing Of Vertebrate Pest Control Agents, Paul Ochs Mar 1972

Efficacy Testing Of Vertebrate Pest Control Agents, Paul Ochs

Vertebrate Pest Conference Proceedings: 5th (1972)

Justification for efficacy testing is provided under the present FIFRA, and the PR notice 70-15 requirements. In addition, the Pure Food and Drug Laws, the Delaney Amend-ment and other laws effect the requirements of registration of all economic poisons. Basic preliminary registration information such as toxicological data, chemistry data, must be provided on all chemicals proposed as economic poisons. Once the basic chemical and toxi-cological properties have been determined, the applicant must consider basic efficacy requirements. Efficacy requirements should consider the effects of particle size and shape, taste and odor, impurities, diluents, stickers and solvents, volatility, mode of action, and …


The Problem Of Anticoagulant Rodenticide Resistance In The United States, William B. Jackson, Dale E. Kaukeinen Mar 1972

The Problem Of Anticoagulant Rodenticide Resistance In The United States, William B. Jackson, Dale E. Kaukeinen

Vertebrate Pest Conference Proceedings: 5th (1972)

Resistance of commensal rodents to anticoagulant rodenticides is not a new phenomenon. Its confirmed presence in several areas of northern Europe is wel1-documented (Jackson 1969, 1972; Bentley 1969; Lund 1969). Not until 1971 was a similar situation with the Norway rat (Rattus norvegicus) to be demonstrated in the United States (Jackson et al. 1971). Because it represents an initial occurrence, the site and background observations will be described in some detail. The rural area involved around Cleveland School in Johnson County is 25 miles SE of Raleigh, N. C. and about five miles in diameter (fig. 1). The typical farm …


House Mouse Behavior And Its Significance To Control, W. D. Klimstra Mar 1972

House Mouse Behavior And Its Significance To Control, W. D. Klimstra

Vertebrate Pest Conference Proceedings: 5th (1972)

It seems explicitly evident that animal control practices must now, and especially in the future, emphasize fuller appreciation of the habits of each kind of animal. Further, this will require consideration be given to behavioral aspects as expressed by a population as a whole of a given species, as well as each individual animal within that population. Animals react with one another and with all characteristics of their environment; and, this in turn results in an identifiable reaction or behavior of each population as a unit of social organization. Although within broad limits some aspects of these responses, whether individual …


The Influence Of Attractants And Repellents On The Feeding Behaviour Of Rattus Norvegicus, J. O. Bull Mar 1972

The Influence Of Attractants And Repellents On The Feeding Behaviour Of Rattus Norvegicus, J. O. Bull

Vertebrate Pest Conference Proceedings: 5th (1972)

Poison baits are extensively used for commensal rodent control; considerable folk lore exists regarding the use of additives to induce rodents to come to and eat poison baits. This paper describes a rational evaluation of attractants and the influence of different odours in inducing Rattus norvegicus to feed at given locations. The influence of certain repellents was also examined. Tests consisted of attempts to induce rats to feed at non-preferred sites or to repel them from preferred sites. Place preference was the dominant factor in feeding by rats, and odours failed to influence feeding activity significantly.


Rat Reduction With Indigenous Methods, P. J. Deoras Mar 1972

Rat Reduction With Indigenous Methods, P. J. Deoras

Vertebrate Pest Conference Proceedings: 5th (1972)

Mujumdar (1968) has recorded that there are 566,000 villages in India as compared to 2699 towns, and that there is 322,460,000 acres of cultivable land and probably 500 million domestic rats in India. The food production target in 1968 in India was to be 110 million tons. National rodent committee 1967 mentioned of a loss of one million ton of food grains by rats alone. Deoras (1968) has mentioned that 3 common rats in Bombay were consuming 26 gm. of food grains per day, that is, about one ounce, while the quantum of cereal rations available per man in some …