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Masters Theses

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Articles 61 - 90 of 254

Full-Text Articles in Animal Sciences

Quantifying Bat Detection Survey Methods And Activity Patterns, Tara C. Hohoff Jan 2016

Quantifying Bat Detection Survey Methods And Activity Patterns, Tara C. Hohoff

Masters Theses

Bats have an astonishing diversity and provide vital ecosystem services in an array of different niches. In North America, most species of bats are insectivores and tend to be frequently overlooked for their important ecosystem role providing insect control. As bat populations have declined in recent years, farmers, land managers, conservationists, and bat enthusiasts have wondered what we can do to protect our local bat populations. As a first step, we need to develop methods that more effectively survey for rare species of bats. By performing inefficient surveys, we are doing a disservice to our funding agencies providing misinformation that …


One Fish, Two Fish, Red Fish, Blue Fish: The Analysis Of The Specter Cell Cycle Mutant In Zebrafish, Tetiana Petrachkova Jun 2015

One Fish, Two Fish, Red Fish, Blue Fish: The Analysis Of The Specter Cell Cycle Mutant In Zebrafish, Tetiana Petrachkova

Masters Theses

Cell division is controlled by genes that regulate the cell cycle. Here we show that the zebrafish specter (spr) mutant is mutation in the cyclin B1 gene, a gene necessary for the G2 to M transition of the cell cycle.

The spr mutation mapped to the cyclin B1 gene. Sequencing showed a transition (C139→T) that caused a nonsense mutation in exon 2 of the cyclin B1 gene. In situ hybridization of cyclin B1 revealed that the mRNA is absent in the mutant embryo by gastrulation. We found that the earliest visible mutant phenotype was a darkening of the head caused …


Progressive Decline Of Testicular Function In Leptinreceptor Deficient Obese Mice, Jennifer Long May 2015

Progressive Decline Of Testicular Function In Leptinreceptor Deficient Obese Mice, Jennifer Long

Masters Theses

The incidence of obesity and metabolic syndrome among the human population is increasing, but the effects on male fertility are unresolved. Leptin insensitivity appears to show a consistent relationship between obesity and fertility problems in men. Genetically modified mice lacking the leptin hormone (ob/ob) or leptin receptor (db/db) are reported to be subfertile and/or infertile but there is only minimal information about testicular function (sperm and hormone production) and the progression of infertility. Therefore, this study was designed to investigate testicular function using a leptin-receptor-deficient obese mouse model (the POUND mouse; Charles River). Testicular sperm production is reduced in POUND …


Daily Activity Patterns In Three Migratory Bird Species At A Stopover Site On The Northern Coast Of The Gulf Of Mexico, Lynn Schofield Jan 2015

Daily Activity Patterns In Three Migratory Bird Species At A Stopover Site On The Northern Coast Of The Gulf Of Mexico, Lynn Schofield

Masters Theses

CHAPTER I: A Comparison of Diel Movement Patterns in Three Bird Species at a Stopover Site on the Northern Coast of the Gulf of Mexico

During migration, birds require stopover habitats where they stop en route to rest, refuel, and prepare for the next stage of their migration. For songbirds, many short movements made within a stopover habitat are known to be costlier than a single long migratory flight, as it takes a considerable amount of energy to initiate flight. This indicates that migrating birds should strive to balance the energy expenditure made in movement during stopover and energy gains …


Asian Carp Population Status And Reproductive Potential In Illinois River Tributaries, Clinton Wesley Morgeson Jan 2015

Asian Carp Population Status And Reproductive Potential In Illinois River Tributaries, Clinton Wesley Morgeson

Masters Theses

Large floodplain rivers are among the most complex natural systems characterized by exchange between the river and its floodplain. Information regarding fishes in main channel habitats is abundant, however much less understanding extends into their tributaries. Tributaries of large rivers provide critical habitats for main channel fishes, important for foraging, spawning, and refuge. In addition to native diversity, large rivers are host to multiple exotic species invasions, threatening biodiversity, ecosystem function, and habitat quality. Two notorious invaders are Silver Carp (Hypophthalmichthys molitrix) and Bighead Carp (H. nobilis), collectively Asian Carp, presenting an imminent threat of invasion …


Adaptive Significance Of Aberrant Chickadee Song In Illinois, Evan Andrew Glynn Jan 2015

Adaptive Significance Of Aberrant Chickadee Song In Illinois, Evan Andrew Glynn

Masters Theses

I studied the behavioral responses of Black-capped (Poecile atricapilus) and Carolina (P. carolinensis) chickadees to playback of Black-capped, Carolina, and aberrant chickadee songs throughout the state of Illinois. These two species are parapatrically distributed throughout the eastern United States, including Illinois. Some areas exist where the ranges of the two species overlap. Individuals in these contact zones often sing aberrant vocalizations. This study focused on the two parental vocalizations (i.e., Black-capped and Carolina song), and two of the most common aberrant vocalizations (the 'Greenville' and 'Vandalia' aberrant dialects), in an attempt to understand the adaptive significance of these aberrant songs. …


Metagenomic Analysis Of The Lacrimal Caruncle Region Of Canis Lupus Familiaris Using Miseq Technology, Seun A. Ikugbayigbe Jan 2015

Metagenomic Analysis Of The Lacrimal Caruncle Region Of Canis Lupus Familiaris Using Miseq Technology, Seun A. Ikugbayigbe

Masters Theses

The identification of ocular microbiota may allow early diagnosis and treatment strategies against eye diseases and disorders with canines. However, clinical microbial identification has been limited to cloning and conventional culture-based studies, which typically underestimate community diversity. In this report, lllumina MiSeq analysis of the 16S rRNA gene was used to examine the microbiome of the lacrimal caruncle region from five healthy dogs. The breeds sampled were a Golden Retriever (Dog A), a Weimaraner (Dog B), a Shih Tzu mix (Dog C), a Yorkie mix (Dog D), and a Dachshund (Dog E). MiSeq analysis revealed a total of 370 operational …


Trophic Interactions In A Semiaquatic Snake Community: Insights Into The Structure Of A Floodplain Food Web, Cynthia M. Carter Jan 2015

Trophic Interactions In A Semiaquatic Snake Community: Insights Into The Structure Of A Floodplain Food Web, Cynthia M. Carter

Masters Theses

Food webs provide a useful conceptual framework for evaluating the relationships that exist within ecological systems. Characterizing the interactions within these webs can improve our understanding of how communities are structured and what mechanisms stabilize them. Untangling these interactions can be an intractable problem in complex systems and insights gained from conventional methods are often accompanied by inherent sources of bias. This study used stable isotope analysis, an alternative to traditional methods, to investigate the roles and relative contributions of consumers at the top of a food web to community structure and stability. I compared the niche parameters of five …


Microglia Respond To Both Permanent And Temporary Deaferentation In The Adult Zebrafish Olfactory Bulb, Amanda K. Mckenna Apr 2014

Microglia Respond To Both Permanent And Temporary Deaferentation In The Adult Zebrafish Olfactory Bulb, Amanda K. Mckenna

Masters Theses

The major goal of this study was to investigate a microglial response following deafferentation in the adult zebrafish, Danio rerio, olfactory bulb. Microglia were identified in the olfactory bulb using the 4c4 antibody and phagocytic-dependent labeling (DiA). Microglia responded to both methods of deafferentation namely, permanent (cautery) and temporary (Triton X- 100). On one and three days following both permanent and temporary deafferentation there was a significant increase in microglia in the treated olfactory bulb. At five and seven days after permanent and temporary deafferentation there was no longer a significant difference between the treated and untreated olfactory bulbs, …


Salmonid Habitat Restoration On The Chocolay River, Michigan, Ross J. Crawford Apr 2014

Salmonid Habitat Restoration On The Chocolay River, Michigan, Ross J. Crawford

Masters Theses

This project seeks to improve salmonid habitat quality by improving riparian vegetation on the adjacent banks (from toe to terrace) on the Chocolay River in Michigan's Upper Peninsula. Quantities of large woody debris (LWD) were also analyzed to determine the heterogeneityof stream habitats, or channel roughness. Percentages of rock, gravel, sand, and silt were analyzed to determine spawning habitat quality. As the proportions of fines (


Demographics And Seasonal Diet Composition Of Shovelnose Sturgeon (Scaphirhynchus Platorynchus Rafinesque) In Wabash River, Vaskar Nepal Jan 2014

Demographics And Seasonal Diet Composition Of Shovelnose Sturgeon (Scaphirhynchus Platorynchus Rafinesque) In Wabash River, Vaskar Nepal

Masters Theses

Shovelnose sturgeon Schaphirhynchus platorynchus Rafinesque, one of the only sturgeon species that support a sustainable commercial harvest, are fished in a substantial caviar fishery in the lower Wabash River. However, ecological information on the population is sparse. In this thesis, I present information on the status and seasonal diet characteristics of the population. A 14-year long shovelnose sturgeon monitoring survey conducted by Illinois Department of Natural Resources shows that the population is in relatively good condition, faces low mortality rates, and has a high potential for recruitment. Study of the seasonal composition of diet suggests that shovelnose sturgeon generally get …


Aspects Of The Trophic Ecology Of An Invertivorous Snake Community, Meagan Amanda Thomas Jan 2014

Aspects Of The Trophic Ecology Of An Invertivorous Snake Community, Meagan Amanda Thomas

Masters Theses

Understanding the significance of trophic links has been of interest to ecologists for decades, likely because food web studies have the potential to reveal a considerable amount of information in the fields of ecosystem and community ecology. Despite the intrinsic benefits that come from elucidating food web structures, doing so is often problematic because of the complex and dynamic nature of ecological communities. The dietary ecology of small-bodied invertivorous snakes remains relatively understudied compared to other snake species. Many of these species are abundant throughout their range, making them ideal organisms for studying community-level questions. I employed a combination of …


Assessment Of Range, Habitat Use, And Diel Movement Of Flathead Catfish (Pylodictis Olivaris) In The Wabash River Using Ultrasonic Telemetry, Sarah Mary Huck Jan 2014

Assessment Of Range, Habitat Use, And Diel Movement Of Flathead Catfish (Pylodictis Olivaris) In The Wabash River Using Ultrasonic Telemetry, Sarah Mary Huck

Masters Theses

Flathead Catfish (Pylodictis olivaris) are one of the most targeted species for recreational and commercial fishing within the Mississippi River Basin. With heavy harvest pressure placed on many populations, proper management is crucial; however, the species range, habitat requirements, and diel movement patterns have rarely been investigated in free flowing rivers. Therefore, I used ultrasonic telemetry with active tracking to monitor movement and habitat use of 44 Flathead Catfish from August 2012 to December 2013 in the lower 280 km of the Wabash River. This system is ideal to evaluate broad and fine scale movement of Flathead Catfish …


Dietary Ecology Of An Actively-Foraging Snake Species: Coluber Constrictor Foxii, Corissa Pauline Lennon Jan 2013

Dietary Ecology Of An Actively-Foraging Snake Species: Coluber Constrictor Foxii, Corissa Pauline Lennon

Masters Theses

The trophic niche width of a species varies depending on the foraging strategy employed by the individuals within a population. Among reptiles, the niche breadth of many species of snakes is relatively understudied. Within this clade, the genus Coluber includes wide-ranging, actively foraging snakes that have been historically labeled as dietary generalists. The dietary information on Blue Racers (Coluber constrictor foxii) is limited, and little is known about ontogenetic or seasonal differences in the prey species consumed. Additionally, this information is available from gut and fecal content only. In addition to obtaining gut and fecal contents, I employed stable isotope …


Short-Term Responses Of Fish Assemblages To Habitat Restoration In A Small Midwestern Stream, John Leon West Jan 2013

Short-Term Responses Of Fish Assemblages To Habitat Restoration In A Small Midwestern Stream, John Leon West

Masters Theses

Recent efforts to restore stream habitat have become a common practice, yet evaluations of biotic responses to these practices are not as common. I evaluated fish assemblage response to restoration in a reach of Kickapoo Creek, a fourth order stream southwest of Charleston, Illinois. Restoration included 446 meters of bank stabilization, pool scouring keys, and the creation of two artificial riffles. To have a representation of pre-restoration fish assemblages, I sampled four stream reaches of Kickapoo Creek twice before construction of habitat restoration: two control reaches (upstream and downstream) and two restored reaches within a 0.5 km restoration stretch (upstream …


Demographics Of A Commercially Exploited Population Of Flathead Catfish (Pylodictis Olivaris) In The Wabash River, Cassi Jo Moody-Carpenter Jan 2013

Demographics Of A Commercially Exploited Population Of Flathead Catfish (Pylodictis Olivaris) In The Wabash River, Cassi Jo Moody-Carpenter

Masters Theses

Flathead catfish, Pylodictis olivaris, are a popular game and commercial fish in the Midwestern United States. In the lower 322 km of the Wabash River, flathead catfish are commercially and recreationally harvested by Illinois and Indiana fishers. Current management regulations are different between the two states; Illinois and Indiana have minimum length limits of 381 and 254 mm, respectively. Indiana has proposed changing their minimum length limit to 381 mm and allowing only one fish> 889 mm to be harvested per day. My study examined the current status of flathead catfish in the Wabash River to determine a standardized …


The Rise And Fall Of Kin Structure In The Neotropical, Family-Living Buff-Breasted Wren (Cantorchilus Leucotis) In Gamboa, Panama, Sarah C. Alessi Dec 2012

The Rise And Fall Of Kin Structure In The Neotropical, Family-Living Buff-Breasted Wren (Cantorchilus Leucotis) In Gamboa, Panama, Sarah C. Alessi

Masters Theses

Family-living species provide an exciting model to examine how natal dispersal and kin structure influence genetic structuring within local populations. Juvenile buff-breasted wrens (Cantorchilus leucotis) of both sexes delay dispersal and exhibit short-distance natal dispersal, which should lead to kin-structured populations in which relatives of both sexes occupy neighboring territories. Blood samples collected from juvenile and adult wrens in Gamboa, Panama were analyzed using microsatellite markers to determine whether related individuals are spatially clustered on neighboring territories, spatial clusters of relatives change over time, and if kin structure is sex-specific. Global and local spatial autocorrelation analyses detected genetic …


Fish Assemblages In Manistee River Tributaries: Longitudinal Distribution Analysis, Seasonal Variation, And Riparian Improvement Evaluation, Nicholas J. Gressick Jun 2009

Fish Assemblages In Manistee River Tributaries: Longitudinal Distribution Analysis, Seasonal Variation, And Riparian Improvement Evaluation, Nicholas J. Gressick

Masters Theses

Sedimentation affects both stream physical and biological integrity. Improperly designed stream passage accompanied with sedimentation and altered hydrology can impede fish passage and reduce fish assemblage integrity. The purpose of this study was to: 1) quantify impacts of poorly constructed road stream crossings and eroding banks on fish assemblages, and 2) assess these sites as sediment sources and connectivity breaks on entire fish assemblages and individual fish species. Electrofishing was conducted during spring and fall 2004 and 2005. A total of 29 electrofishing reaches were sampled which included 5 road-stream and streambank restoration sites. Sickle Creek (1st order) had reduced …


Community Response To Habitat Restoration In Sickle And Bear Creeks, With Emphasis On Mottled Sculpin In Sickle Creek, Jason Andrew Deboer Apr 2008

Community Response To Habitat Restoration In Sickle And Bear Creeks, With Emphasis On Mottled Sculpin In Sickle Creek, Jason Andrew Deboer

Masters Theses

Habitat restoration is employed by biologists and managers to improve the natural functionality and value of aquatic resources. Systems suffer impairment from many sources, including excessive fine sediment, which negatively affects substrate composition, channel morphology, aquatic invertebrate habitat, and fish reproduction and recruitment. Primary objectives included monitoring the biophysical response to sediment abatement in the Big Manistee River watershed. Secondary objectives included (1) placing the biophysical response to the restoration in the context of a much larger watershed plan, (2) quantifying seasonal mottled sculpin movement and habitat use in Sickle Creek for 1-year, and (3) determining habitat variables which may …


Colony Composition And Demographics Of Beavers In Illinois, Stanley T. Mctaggart Jan 2002

Colony Composition And Demographics Of Beavers In Illinois, Stanley T. Mctaggart

Masters Theses

Beavers (Castor canadensis) have been extensively studied throughout North America, but little research has been conducted on this species in Illinois and the Midwest. Beavers exhibit wide variations in colony composition and demographics over their broad geographic range, so regional research is important for sound management. The objectives of this study were to investigate the: (1) typical composition of beaver colonies in Illinois; (2) reproductive potential of female beavers in Illinois; (3) sex-age composition of beaver populations in Illinois; and (4) efficacy of night-vision surveys versus removal trapping for estimating colony size. This study was conducted during the 1999-00 and …


Mitochondrial Dna And Microsatellite Genetic Variation Of Dollar Sunfish (Lepomis Marginatus), Nancy A. Schable Jan 2002

Mitochondrial Dna And Microsatellite Genetic Variation Of Dollar Sunfish (Lepomis Marginatus), Nancy A. Schable

Masters Theses

Dollar sunfish (Lepomis marginatus) at the Savannah River Site were sampled from two radiocesium contaminated ponds with a history of thermal elevation and from reference ponds with no history of radioactive or thermal contamination. Fluorescent sequencing of a portion of the mitochondrial control region showed no genetic variation within or between populations. Centrarchidae microsatellite loci Lma 120 (6 alleles, N=124 from 5 populations), Lma 20 (10 alleles, N=37 from 3 populations) and Rb 7 (14 alleles. N=17 from 2 populations) were variable for dollar sunfish. An additional 9 microsatellite primer pairs were designed for dollar sunfish. Testing of the designed …


Aging Coyotes Using Dental Characteristics, Michelle Maher Jan 2002

Aging Coyotes Using Dental Characteristics, Michelle Maher

Masters Theses

The accepted methods of age determination in the coyote (Canis latrans) are either highly subjective and unquantifiable or expensive and require the extraction of the canine tooth. Since neither of these methods are ideal, their limitations have impeded research on this species. Therefore, it was my objective to (1) develop and test the accuracy and precision of a descriptive key based on tooth wear patterns on the lower canine tooth, (2) develop and test the reliability of multiple regression models for aging coyotes using measurements from extracted teeth, and (3) suggest criteria for improving the consistency of results …


Renesting - Female's Success After Nesting Failure And The Renesting Of The Dickcissel (Spiza Americana) At Prairie Ridge State Natural Area, Kevin L. Wentworth Jan 2001

Renesting - Female's Success After Nesting Failure And The Renesting Of The Dickcissel (Spiza Americana) At Prairie Ridge State Natural Area, Kevin L. Wentworth

Masters Theses

Renesting - Female's success after nesting failure. Many birds are unsuccessful in their first nesting attempt, so renesting is often a very important way for birds to increase their lifetime fitness and for populations to maintain stable numbers. I examined the importance of renesting and the factors that encourage or discourage a female from renesting and also the factors that affect the success of these renests. I also looked for patterns in renesting behavior (e.g., renesting interval, renesting distance, percentage of females that attempt renests, and the success of renests) of birds by comparing different studies. I used a total …


The Effect Of Predator Chemical Cues And Conspecific Alarm Signals Upon Behavior In Early And Late Developmental Stages Of American Toad (Bufo Americanus) Tadpoles, Carol Lynette Johnson Jan 2000

The Effect Of Predator Chemical Cues And Conspecific Alarm Signals Upon Behavior In Early And Late Developmental Stages Of American Toad (Bufo Americanus) Tadpoles, Carol Lynette Johnson

Masters Theses

The chemosensory capability and subsequent habitat choice of larval American toad (Bufo americanus) tadpoles were quantified using choice of refuge with both early and late developmental stages. Treatments were performed with two tadpole densities to ascertain the effect of social aggregations upon behavior. Bluegill (Lepomis macrochirus) and predaceous diving beetle larvae (Dytiscus sp.) predators were used to condition water. Conspecific tadpoles as well as Southern leopard frog (Rana sphenocephala) tadpoles were used to prepare treatment extracts.

Tadpole density (n=10 and n=20) had no significant effect upon the percentage of tadpoles seeking cover …


Patterns And Implications Of Aberrant Singing Behaviors Of Black-Capped (Poecile Atricapillus) And Carolina (Poecile Carolinensis) Chickadees In Illinois, Patrick Caesar Enstrom Jan 2000

Patterns And Implications Of Aberrant Singing Behaviors Of Black-Capped (Poecile Atricapillus) And Carolina (Poecile Carolinensis) Chickadees In Illinois, Patrick Caesar Enstrom

Masters Theses

I studied the singing behavior of the closely related Black-capped (Poecile atricapillus) and Carolina (Poecile carolinensis) Chickadees along their range interface in central Illinois. These sibling species are parapatrically distributed from the Appalachians through the Midwest to Kansas. Where their ranges do overlap, small hybrid zones form and chickadees in these areas frequently sing aberrant songs. The majority of the songs studied were recorded 17 April-16 July 1999 in fifteen counties throughout central Illinois. I measured 8 frequency and duration characteristics of the first two notes of songs that began with two whistled notes. The averages of these characteristics …


Effects Of Leafy Spurge (Euphorbia Esula) Infestation On Breeding Birds Of The Sheyenne National Grassland, Nd, Daniel M. Scheiman Jan 2000

Effects Of Leafy Spurge (Euphorbia Esula) Infestation On Breeding Birds Of The Sheyenne National Grassland, Nd, Daniel M. Scheiman

Masters Theses

Leafy spurge (Euphorbia esula) is an exotic invasive weed in the northern Great Plains. We examined the effects of leafy spurge infestation on densities and nest success of breeding birds in grasslands on the Sheyenne National Grassland (SNG), ND. We categorized spurge-infested grasslands into three levels of infestation, based on the area covered by spurge patches: (a) low (0-20%), (b) medium (20-60%) and, (c) high (> 60%). We surveyed 60 100-m radius circular plots (20 in each category), and searched for nests in three 16-ha plots (one in each category). There were no statistically significant differences in mean species richness …


The Role Of Bowfin, Amia Calva, In Multiple Species Management Plans, Benjamin Jacob Hausmann Jan 1998

The Role Of Bowfin, Amia Calva, In Multiple Species Management Plans, Benjamin Jacob Hausmann

Masters Theses

The major challenge to fisheries managers of the 21st century will be to maintain the diversity, not only of fishing opportunity, but also of traditionally non-game and economically unimportant species. With the relatively recent understanding of the importance of ecosystem level management, attention is being focused on native species that were often ignored or eradicated under past management practices. One such fish that has been largely ignored is the bowfin, Amia calva. Ecological data pertaining to bowfin natural history are limited and to date no attempt has been made to integrate bowfin into fisheries management decisions within the species native …


Habitat Selection, Reproductive Success, And Impaling Patterns Of A Migratory Population Of Loggerhead Shrikes, Jeffrey D. Esely Jr. Jan 1998

Habitat Selection, Reproductive Success, And Impaling Patterns Of A Migratory Population Of Loggerhead Shrikes, Jeffrey D. Esely Jr.

Masters Theses

I studied habitat selection and reproductive success of a migratory population of Loggerhead Shrikes (Lanius ludovicianus migrans) as well as the temporal and spatial patterns of impaling exhibited by this population during the nesting season. The selection of breeding habitat was investigated at different spatial scales. Thirty-eight (67%) of 57 nests were located in osage orange (Maclura pomifera) trees. Shrike territories (area ≤ 200 m from nest site) contained significantly more pasture, fenceline, and perch sites, but less com, alfalfa, and forest than random sites. At larger spatial scales, more grassland was detected within 300 m …


A Comparison Of Predation Rates On Real And Artificial Nests Of Grassland Birds, William B. Davison Jan 1998

A Comparison Of Predation Rates On Real And Artificial Nests Of Grassland Birds, William B. Davison

Masters Theses

I compared rates of predation between real and artificial nests of grassland birds in order to test the impact of nest type, nest position, and egg size on predation rates. I distributed wicker avicultural baskets and realistic grass nests baited with a clay egg and either northern bobwhite (Colinus virginianus) or house sparrow (Passer domesticus) eggs in four Conservation Reserve Program (CRP) grasslands in east-central Illinois. Nest success averaged 86.5% for 12 days of exposure for artificial nests. For real nests, nest success was markedly lower; averaging 39% over the entire nesting cycle and 59% during approximately 12 days of …


Heartworm And Lungworms In Illinois' Canids And Their Possible Effect On Coyote Condition And Reproduction, David G. Gregory Jan 1998

Heartworm And Lungworms In Illinois' Canids And Their Possible Effect On Coyote Condition And Reproduction, David G. Gregory

Masters Theses

This study focuses on the prevalence of heartworm and lungworms in Illinois' canid species, and the effect that they may have on condition (body weight, kidney fat, marrow fat) and reproduction (placental scars) on coyote populations. A total of 1,150 coyotes (Canis latrans), 2,269 domestic dogs, 47 red foxes (Vulpes vulpes), and 2 gray foxes (Urocyon cinereoargenteus) were examined. Prevalence of heartworms (Dirofilaria immitis) averaged 17.8% in coyotes, 3.0% in domestic dogs, 2.0% in red foxes, and 0% in gray foxes. Domestic dogs not receiving any type of prophylactic treatment had a higher prevalence (12.5%) of heartworms than dogs on …