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Full-Text Articles in Life Sciences

Did Predator Control Go To The Dogs? A 40-Year Retrospective, John M. Tomeček Jan 2019

Did Predator Control Go To The Dogs? A 40-Year Retrospective, John M. Tomeček

Human–Wildlife Interactions

In 1980, Green and Woodruff published an article entitled, “Is Predator Control Going to the Dogs?” At that time, the use of Livestock Guardian Dogs (hereafter LGDs) was a relatively new wildlife damage management tool in North America. Although this tool passed the test of time in its point of origin, early North American adopters stepped into a brave new world with little to guide them. In the modern world, knowledge of methods and means of wildlife damage management exists in written texts, films, and other guides. For LGDs, however, such materials did not exist 40 years ago. Over the ...


Predicting Black Bear Activity At Backcountry Campsites In Bryce Canyon National Park, Utah, Wesley G. Larson, Tom Smith Jan 2019

Predicting Black Bear Activity At Backcountry Campsites In Bryce Canyon National Park, Utah, Wesley G. Larson, Tom Smith

Human–Wildlife Interactions

Developing the capacity to predict black bear (Ursus americanus; bear) activity in a diversity of habitats will help conserve bear populations and their habitats and minimize human–bear conflicts. This capacity will be particularly important in areas that provide bear habitat and offer backcountry hiking and camping experiences. Bryce Canyon National Park (BRCA), located on the edge of the Paunsaugunt Plateau in southern Utah, USA, provides important bear habitat and offers visitors 12 backcountry campsites. To effectively manage these areas to minimize human–bear conflicts, park managers will need better information about black bear use of these campsites and other ...


Factors Influencing The Movement Of Livestock Guardian Dogs In The Edwards Plateau Of Texas: Implications For Efficacy, Behavior, And Territoriality, John M. Tomeček, Justin T. French, John W. Walker, Nova J. Silvy, Nicholas A. Bromen Jan 2019

Factors Influencing The Movement Of Livestock Guardian Dogs In The Edwards Plateau Of Texas: Implications For Efficacy, Behavior, And Territoriality, John M. Tomeček, Justin T. French, John W. Walker, Nova J. Silvy, Nicholas A. Bromen

Human–Wildlife Interactions

Livestock guardian dog (Canis lupus familiaris; LGD) breeds of domestic dog worldwide provide a degree of control over predation losses. The application of LGDs as a wildlife damage management tool evolved as a cultural practice in the Old World. In the 1970s, this tool emerged in North America. Despite several decades of science and application, gaps still exist in our knowledge regarding applications for LGDs. From February 2016 to November 2017, we deployed global positioning system transmitters on 4 LGDs on a 20-km2 ranch in Menard County, Texas, USA operated by Texas A&M AgriLife Research to investigate their ...


Spatial Relationships Between Livestock Guardian Dogs And Mesocarnivores In Central Texas, Nicholas A. Bromen, Justin T. French, John Walker, Nova J. Silvy, John M. Tomeček Jan 2019

Spatial Relationships Between Livestock Guardian Dogs And Mesocarnivores In Central Texas, Nicholas A. Bromen, Justin T. French, John Walker, Nova J. Silvy, John M. Tomeček

Human–Wildlife Interactions

The use of livestock guardian dogs (Canis lupus familiaris; LGDs) to deter predators from preying on domestic sheep (Ovis aries) and goat (Capra spp.) herds continues to increase across the United States. Most research regarding the efficacy of LGDs has been based on queries of rancher satisfaction with LGD performance, yet little is known regarding LGD influence on mesocarnivores, including those species against which they protect livestock. Here, we provide some preliminary observations regarding the effect of LGDs deployed with sheep and goat herds from May 2016 to April 2017 on the detected activity of mesocarnivores within occupied pastures on ...


Portable Electric Fencing For Bear Deterrence And Conservation, Tom S. Smith, Bryan Hopkins, John Gookin, Samantha Thompson Jan 2018

Portable Electric Fencing For Bear Deterrence And Conservation, Tom S. Smith, Bryan Hopkins, John Gookin, Samantha Thompson

Human–Wildlife Interactions

Although bear-inflicted (Ursus spp.) human fatalities are rare in North America, human injuries, property damage, and bear mortalities occur wherever bears and humans commingle. We investigated the efficacy of portable electric fencing systems for bear deterrence under a variety of environmental conditions in the lab and field. Our results showed that the bear deterrent systems we evaluated were effective in protecting humans, their food, and property from bears >99% of the time. Herein, we discuss the benefits of using electric fencing, reasons why fences sometimes fail, and provide guidance regarding the most effective implementation of the systems we evaluated. Lastly ...


Post-Release Activity And Habitat Selection Of Rehabilitated Black Bears, Patrick J. Myers, Julie K. Young Jan 2018

Post-Release Activity And Habitat Selection Of Rehabilitated Black Bears, Patrick J. Myers, Julie K. Young

Human–Wildlife Interactions

Despite the long history of wildlife rehabilitation and the abundance of empirical knowledge of the behavior and resource selection of wildlife species, rarely does research bridge these disciplines. Such investigations could be of value to wildlife managers and rehabilitators by revealing the suitability of the habitat at selected release sites, the wild activities, behavior, and fitness of the captive-reared individuals, and ultimately the efficacy of the rehabilitation process. Rehabilitated carnivores warrant specific attention, given that they are wide-ranging and may behave in ways that threaten human safety or interests. We investigated the behavior of orphan, rehabilitated black bear cubs (Ursus ...


Motivations And Satisfaction Of North Dakota Deer Hunters During A Temporal Decline In Deer Populations, Kristen E. Black, William F. Jensen, Robert Newman, Jason R. Boulanger Jan 2018

Motivations And Satisfaction Of North Dakota Deer Hunters During A Temporal Decline In Deer Populations, Kristen E. Black, William F. Jensen, Robert Newman, Jason R. Boulanger

Human–Wildlife Interactions

Achieving state wildlife agency biological goals for deer (Odocoileus spp.) management may often conflict with hunter desires. Concomitantly, better information is needed to optimize agency deer herd management goals with hunters’ social goals. In 2016, we surveyed 3,000 North Dakota, USA, resident deer hunters using a self-administered mail survey to gain a better understanding of motivations, satisfaction, and hunter demographics that may be used to inform hunter recruitment and retention (HRR) efforts during a period of reduced statewide deer populations. With deer-gun license availability strictly limited, we explored the possibility that some gun hunters may have been engaging in ...


Canid Vs. Canid: Insights Into Coyote-Dog Encounters From Social Media, Erin E. Boydston, Eric S. Abelson, Ari Kazanjian, Daniel T. Blumstein Jan 2018

Canid Vs. Canid: Insights Into Coyote-Dog Encounters From Social Media, Erin E. Boydston, Eric S. Abelson, Ari Kazanjian, Daniel T. Blumstein

Human–Wildlife Interactions

While the relationship between coyotes (Canis latrans) and house cats (Felis catus) may be characterized as one between predators and their prey, coyote interactions with domestic dogs (C. lupus familiaris) appear to be more varied and may include behaviors associated with canid sociality. While encounters between coyotes and dogs are difficult to observe, we capitalized on publically available video recordings of coyote-dog encounters to observe canid behaviors and examined 35 video clips downloaded from YouTube during fall 2014. We identified coyote-dog interactions that were playful, agonistic, or predatory; those that we could not clearly categorize were labeled as other/undetermined ...


Strike Hazard Posed By Columbids To Military Aircraft, Melanie R. Colón, Ashley M. Long Jan 2018

Strike Hazard Posed By Columbids To Military Aircraft, Melanie R. Colón, Ashley M. Long

Human–Wildlife Interactions

Wildlife-aircraft strikes threaten both human and animal safety and result in hundreds of millions of dollars per year in aircraft damage and lost flight hours. Large-bodied birds are especially hazardous to aircraft. However, given high-speed flight at low altitudes, military aircraft may be especially vulnerable to strikes and more susceptible to damage even when encountering small birds. We summarized all wildlife-aircraft strike records from Randolph Air Force Base (San Antonio, Texas) over a 25-year period and compared the number and cost of strikes across avian species and species groups. Because columbids (i.e., pigeons and doves) are among the most ...


Learning To Live With Wolves: Community-Based Conservation In The Blackfoot Valley Of Montana, Seth M. Wilson, Elizabeth H. Bradley, Gregory A. Neudecker Dec 2017

Learning To Live With Wolves: Community-Based Conservation In The Blackfoot Valley Of Montana, Seth M. Wilson, Elizabeth H. Bradley, Gregory A. Neudecker

Human–Wildlife Interactions

We built on the existing capacity of a nongovernmental organization called the Blackfoot Challenge to proactively address wolf (Canis lupus)-livestock conflicts in the Blackfoot Valley of Montana. Beginning in 2007, wolves started rapidly recolonizing the valley, raising concerns among livestock producers. We built on an existing program to mitigate conflicts associated with an expanding grizzly bear population and worked within the community to build a similar program to reduce wolf conflicts using an integrative, multi-method approach. Efforts to engage the community included one-on-one meetings, workshops, field tours, and regular group meetings as well as opportunities to participate in data ...


Humans As Prey: Coping With Large Carnivore Attacks Using A Predator-Prey Interaction Perspective, Vincenzo Penteriani, Giulia Bombieri, José María Fedriani, José Vicente López-Bao, Pedro José Garrote, Luca Francesco Russo, María Del Mar Delgado Sep 2017

Humans As Prey: Coping With Large Carnivore Attacks Using A Predator-Prey Interaction Perspective, Vincenzo Penteriani, Giulia Bombieri, José María Fedriani, José Vicente López-Bao, Pedro José Garrote, Luca Francesco Russo, María Del Mar Delgado

Human–Wildlife Interactions

The number of attacks on humans by large carnivores in North America is increasing. A better understanding the factors triggering such attacks is critical to mitigating the risk of future encounters in landscape where humans and large carnivore co-exist. Since 1955, of the 632 attacks on humans by large carnivores, 106 (17%) involved predation. We draw on concepts and empirical evidence from the Predator-Prey Interaction Theory to provide insights into how to reduce predatory attacks and, thus, improve human-large carnivore co-existence. Because large carnivore-caused mortality risks for humans are comparable to those shown by other mammal species in response to ...


Factors Influencing Relocation Success Of Utah Prairie Dog (Cynomys Parvidens), Rachel Curtis Dec 2012

Factors Influencing Relocation Success Of Utah Prairie Dog (Cynomys Parvidens), Rachel Curtis

All Graduate Theses and Dissertations

Utah prairie dogs (Cynomys parvidens) have been extirpated in 90% of their historical range. Because most of the population occurs on private land, this threatened species is continually in conflict with landowners. The Utah Division of Wildlife Resources has been relocating prairie dogs from private to public land since the 1970s, but relocations have been largely unsuccessful due to high mortality. Prairie dogs are highly social animals, but they are usually relocated without regard to their family group (coterie). I hypothesized that relocating Utah prairie dogs with their social structure intact may positively affect their survival rates and behavior. Utah ...


The Status Of Dwarfed Populations Of Short-Horned Lizards (Phrynosoma Hernandesi) And Great Plains Toads (Anaxyrus Cognatus) In The San Luis Valley, Colorado, Megan E. Lahti Dec 2010

The Status Of Dwarfed Populations Of Short-Horned Lizards (Phrynosoma Hernandesi) And Great Plains Toads (Anaxyrus Cognatus) In The San Luis Valley, Colorado, Megan E. Lahti

All Graduate Theses and Dissertations

The San Luis Valley is a large valley formation in Colorado surrounded on either side by mountain ranges exceeding 4,267 m. Within the Valley, two of the 14 amphibian and reptile species are dwarfed: the short-horned lizard (Phrynosoma hernandesi) and the Great Plains toad (Anaxyrus cognatus). Since its initial reporting in 1968 and confirmation in 1981, no research further investigating this dwarfism has been conducted. I collected morphological measurements to determine the extent and patterns of dwarfism of both species. I then investigated the genetics of both species using mitochondrial DNA to determine whether they are genetically distinct, their ...


Comparative Ecology Of Narrowly Sympatric Horned Lizards Under Variable Climatic Conditions, Kevin V. Young May 2010

Comparative Ecology Of Narrowly Sympatric Horned Lizards Under Variable Climatic Conditions, Kevin V. Young

All Graduate Theses and Dissertations

We studied the Flat-tailed Horned Lizard, Phrynosoma mcallii, and the Sonoran Horned Lizard, P. goodei, in an area of narrow sympatry near Yuma, Arizona, and found they overlapped broadly in use of available food resources, body size, and growth rates. We compared diet (Chapter 2), growth and reproduction (Chapter 3), and survivorship (Chapter 4) of P. mcallii and P. goodei during two years of drought followed by a year of higher-than-average rainfall. We predicted that P. mcallii would be more tolerant of drought conditions than its congener, since P. mcalliiis found only in an extremely arid region while P. goodei ...


A Conceptual Framework For Understanding Effects Of Wildlife Water Developments In The Western United States, Randy T. Larsen Dec 2008

A Conceptual Framework For Understanding Effects Of Wildlife Water Developments In The Western United States, Randy T. Larsen

All Graduate Theses and Dissertations

Free water can be a limiting factor to wildlife in arid regions of the world. In the western United States, management agencies have installed numerous, expensive wildlife water developments (e.g. catchments, guzzlers, wells) to: 1) increase the distribution or density of target species, 2) influence animal movements, and 3) mitigate for the loss of available free water. Despite over 50 years as an active management practice, water developments have become controversial for several species. We lack an integrated understanding of the ways free water influences animal populations. In particular, we have not meshed understanding of evolutionary adaptations that reduce ...


Garter Snake (Thamnophis) Natural History: Food Habits And Interspecific Aggression, Michael J. Edgehouse Dec 2008

Garter Snake (Thamnophis) Natural History: Food Habits And Interspecific Aggression, Michael J. Edgehouse

All Graduate Theses and Dissertations

Communication and recognition are closely intertwined and have been well documented in closely related species over the past several decades. These two types of behaviors often will aid in fostering or disrupting coexistence of similar species. Frequently, it is through different diet patterns that similar species will be able to coexist. This study uses data from 1972 through 2006 to demonstrate the diet of Thamnophis sirtalis, T. atratus, T. elegans, and T. couchii throughout their California range of sympatry with Taricha torosa. Additionally, an in depth examination of the diet of T. sirtalis, T. elegans, and T. atratus was conducted ...


Disturbance As Restoration In The Intermountain Sagebrush Steppe: Effects On Non Target Bird Species, Russell Edward Norvell Dec 2008

Disturbance As Restoration In The Intermountain Sagebrush Steppe: Effects On Non Target Bird Species, Russell Edward Norvell

All Graduate Theses and Dissertations

Changes in shrubsteppe passerine bird habitat associations in response to disturbance were investigated at multiple temporal and spatial scales. Spatial measures incorporated the effects of area at different ecological scales (nest site, territory, and landscape) to include ecologically meaningful extents. Temporal measures included seasonal and annual effects, and were designed to detect lagged responses should they occur. Local-to-landscape scale effects of mechanical restoration treatments on local extirpation and abundances of nine species indicated most were insensitive to changes in habitat quality, while abundance models showed only broad declines. Changing the availability of nesting habitat on both the attractiveness and quality ...


Vocalization In A Population Of Green-Tailed Towhees (Chlorura Chlorura), Timothy Andrus Burr May 1974

Vocalization In A Population Of Green-Tailed Towhees (Chlorura Chlorura), Timothy Andrus Burr

All Graduate Theses and Dissertations

Studies of vocalizations in a montane population of Green-Tailed Towhees were conducted during the summer months of 1971 and 1972 in Cache County, Utah. The song and call repertoiries of 10 breeding pairs were recorded and analyzed on a sound spectograph.

Males averaged 8.7 different song and 18.2 different not types. Song variation on the population level is high (58 different songs) but the sharing of these songs among the males is low (22.4) . Populational note structure is equally diverse but reveals a greater degree of sharing (75%).

Both males and females used three calss, the meow ...


Ecology Of Aroga Websteri Clarke In Curlew Valley, Utah-Idaho, Reed L. Kirkland May 1972

Ecology Of Aroga Websteri Clarke In Curlew Valley, Utah-Idaho, Reed L. Kirkland

All Graduate Theses and Dissertations

The ecology, life history, and population dynamics of the sagebrush defoliator, Aroga websteri Clarke, were studied in the field and laboratory. The defoliator has one generation a year at the Curlew Valley site. It overwintered in the egg stage and passed through five larval instars. Ten parasite species attacked the defoliator at the study site . Four species, Orgilus ferus, Phaeogenes sp., Spilochalcis leptis, and Apanteles cacoeciae, contributed over 75 percent of the total incidence of parasitism. Parasitism ranged from 20 to 76 percent in 1971, but only ranged from 6 to 29 percent in 1972. This decrease in total parasitism ...


The Effect Of Chromosomal Position On Dosage Compensation And Ontogenic Expression Of The V+ Gene In D. Melanogaster, Jack E. Tobler May 1971

The Effect Of Chromosomal Position On Dosage Compensation And Ontogenic Expression Of The V+ Gene In D. Melanogaster, Jack E. Tobler

All Graduate Theses and Dissertations

Two manifestations of gene regulation-- dosage compensation and ontogenic regulation--were examined in normally positioned and relocated v+ genotypes in Drosophila melanogaster to determine the role of gene position in these control functions. Enzyme assays, used as criteria of gene activity, were performed on various genotypes containing different doses of v+ in normal and relocated positions in male and female flies. The results indicate that although differently positioned v+ genes may specify different tryptophan pyrrolase activities, they still show dosage compensation. In each case, the enzyme activity associated with each gene, either on the X, Y, or third chromosome, is twice ...


The Effects Of Formaldehyde On The Frequency Of Reversion Of The White-Ivory Mutant Of Drosophila Melanogaster, Ruth Ellen D. Wood May 1970

The Effects Of Formaldehyde On The Frequency Of Reversion Of The White-Ivory Mutant Of Drosophila Melanogaster, Ruth Ellen D. Wood

All Graduate Theses and Dissertations

This study is an analysis of the effects of formaldehyde, a chemical which is both recombinogenic and mutagenic, on white-ivory (wi) a highly mutable allele of the white locus of Drosophila.

Formaldehyde is shown to significantly increase the reversion frequency of wi. The results of this investigation differ from earlier observations in three respects: (1) there is a positive correlation between RNA (ribonucleic acid) concentration and reversion frequency in the presence of formaldehyde, but reversion does not appear to be totally RNA dependent; (2) female germ cells are more sensitive than those of the male; and ( 3) a ...


Summer Distribution And Food Habits Of Microtus, James B. Monroe May 1969

Summer Distribution And Food Habits Of Microtus, James B. Monroe

All Graduate Theses and Dissertations

Field work for the study was conducted in Logan Canyon and the valley at the base of that canyon in Cache County, Utah, during the three summer months of both 1968 and 1969, Microtus pennsylvanicus, found only in the valley, inhabits wet marshy areas. Microtus longicaudus is found in mixed deciduous woods a long the Logan River in the canyon. Microtus richardsoni, which occurs only at the higher elevations, inhabits the subalpine meadows . Microtus montanus inhabits mesic grassy fields in both the valley and Logan Canyon and also inhabits a mixed deciduous woods and tall canary grass (Phalaris arundinacea) growing ...


Comparisons Of Phytoseiid Predator Population In Sprayed And Unsprayed Apple Orchards In Cache Valley, Utah, Yeboa A. Dodoo May 1968

Comparisons Of Phytoseiid Predator Population In Sprayed And Unsprayed Apple Orchards In Cache Valley, Utah, Yeboa A. Dodoo

All Graduate Theses and Dissertations

A comparative study of phytoseiid populations was made of two well- cultivated and regularly sprayed apple orchards with two unsprayed orchards in Cache Valley, northern Utah.

Two phytoseiid species, Typhlodromus mcgregori Chant and T. occidentalis Nesbitt were observed on the apple leaves, under the bark, and occasionally in the litter and soil. Amblyseius cucumeris (Oudemans) occurred in the soil and litter and occasionally under bark. T. mcgregori was dominant in the unsprayed orchards, and T. occidentalis in the sprayed.

Of the phytophagous mites, which served as food for the phytoseiids, the two-spotted mite, Tetranychus urticae Koch was dominant. Other phytophagous ...


A Description Of The Planarian Phagocata Crenophila, New Species, From Utah, Jerry H. Carpenter May 1968

A Description Of The Planarian Phagocata Crenophila, New Species, From Utah, Jerry H. Carpenter

All Graduate Theses and Dissertations

A new species of planaria in the genus Phagocata was found in several springs and spring-fed streams in Logan Canyon, Cache County, Utah. This species was named Phagocata crenophila because it greatly prefers to live in springs and it seems to be adapted behaviorally to this type of habitat. Serial sections and whole mounts were made by standard methods in order to study the anatomical features which are necessary for identification of planarians. The distinguishing features of this species are the following: testes ventral and extending from near the brain to near the posterior end, ejaculatory duct opening ventrally from ...


Feeding Ecology And Territorial Behavior Of The Yellow Warbler, Merrill J. Frydendall May 1967

Feeding Ecology And Territorial Behavior Of The Yellow Warbler, Merrill J. Frydendall

All Graduate Theses and Dissertations

A controversy dating from the appearance of Altum's book, Der Vogel und sein Leben, 1868 (Mayr, 1935) is that of the biological function or functions of the territorial behavior in birds. However, attention was not focused upon this problem until the advent of Howard's book, Territory in Bird Life, published in 1920. In a general review of the problem Hinde (1956) discussed several functions of the territory and presented evidence both for and against their importance. The more important of these presumed functions are; (1) limitation of population density; (2) facilitation of pair formation and maintenance of the ...


The Incidence And Life Cycle Of Eimeria Utahensis Sp. N. From Kangaroo Rats Of Northwestern Utah, John V. Ernst May 1967

The Incidence And Life Cycle Of Eimeria Utahensis Sp. N. From Kangaroo Rats Of Northwestern Utah, John V. Ernst

All Graduate Theses and Dissertations

A total of 176 kangaroo rats (151 Dipodontys ordii and 25 Q• microps) were captured in northwestern utah and examined for coccidia. Of these 176 rats, four Q• ordii (2.6%) and four Q• microps (16.0%) were infected with ~ utahensis, a new species of coccidia. Little seasonal difference was found in the infection rate of either species. The characteristics of the sporulated oocysts of this species were described. A sporocyst plug was reported for the first time in an eimerian oocyst.

Artificially excysted sporozoites were studied by various methods. Thirty living sporozoites averaged 22.5 p in length by ...


Life Cycles Of Three Species Of Eimeria From The Uinta Ground Squirrel, Spermophilus Armatus, Kenneth S. Todd Jr. May 1967

Life Cycles Of Three Species Of Eimeria From The Uinta Ground Squirrel, Spermophilus Armatus, Kenneth S. Todd Jr.

All Graduate Theses and Dissertations

A study of the conccidia of the Uinta ground squirrel, Spermophilus (Citellus) armatus, was undertaken to determine the incidence of coccidia in a population of these ground squirrels, the life cycle and pathogenicity of the coccidia, and the host specificity of certain of the species of coccidia found in this and five other species of ground squirrels (S. richardsoni, S. variegatus, S. lateralis, S. columbianus, and S. beecheyi).

Uinta ground squirrels were live trapped and their feces examined to determine the incidence of coccidian infection. Specimens of S. armatus were maintained in the laboratory and given a pure inoculum of ...


The Initiation Of Infection By Dna From Bacteriophage Lambda, Gerald D. Elseth May 1966

The Initiation Of Infection By Dna From Bacteriophage Lambda, Gerald D. Elseth

All Graduate Theses and Dissertations

Deoxyribonucleic acid isolated from bacteriophage lambda can infect Escherichia coli K12 in the presence of adsorbed helper phage (Kaiser and Hogness, 1960; Kaiser, 1962). The manner in which lambda DNA enters the cell and the possible role of helper phage in the penetration process is still not clear. Kinetic studies conducted in this laboratory during the initial stages of infection by lambda DNA demonstrate a requirement for helper function during the penetration of an infectious molecule. Further investigation into this problem is needed and was the major objective of this study.


A Study Of Aquatic Insects Of Logan River, Utah, Daood Salman Mutlag May 1955

A Study Of Aquatic Insects Of Logan River, Utah, Daood Salman Mutlag

All Graduate Theses and Dissertations

The author's main purpose is to discover and record what insects are present at different locations in the Logan River during the months of September, 1953, to June, 1954.


An Economic Study Of Rats (Genus Rattus) In Cache County, Utah, John Vincent Bruce May 1951

An Economic Study Of Rats (Genus Rattus) In Cache County, Utah, John Vincent Bruce

All Graduate Theses and Dissertations

The most destructive animals in the world are rats (Rattus sp.). The annual destruction caused by rats in the United States is not known. but it has been estimated to be $189,000,000, according to Silver (1942) of the United States Fish and Wildlife Service. Silver states that our nation’s farmers lose approximately $6,000,000 annually. Rats not only eat vast amounts of food meant for human and livestock consumption, but they contaminate and waste as much or more than they eat. Rats are able to gnaw into buildings, grain bins, and other places were food and ...