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University of Nebraska - Lincoln

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Articles 151 - 180 of 896

Full-Text Articles in Behavior and Ethology

Herons And Egrets, Michael D. Hoy Aug 2017

Herons And Egrets, Michael D. Hoy

Wildlife Damage Management Technical Series

Human-Wildlife Conflicts

Landscapes -- Herons and egrets commonly cause damage at aquaculture facilities and recreational fishing waters where fish are held at high densities. In one study, on average wading birds consumed from 4 to 24 golden shiners per day at minnow production facilities in Arkansas. Great blue herons and great egrets commonly feed at catfish production facilities in Mississippi. The tendency for herons and egrets to congregate in large feeding flocks often leads to extensive loss of fish at aquaculture facilities. Fish-eating birds also can have an impact on intensively managed sport fisheries. Damage occurs when herons and egrets …


Behavioral Plasticity Across Non-Social Contexts In Female Green Swordtails, Xiphophorus Helleri, Lindsey M. Coit May 2017

Behavioral Plasticity Across Non-Social Contexts In Female Green Swordtails, Xiphophorus Helleri, Lindsey M. Coit

School of Biological Sciences: Dissertations, Theses, and Student Research

Phenotypic plasticity is the ability of an individual to alter its phenotype in response to environmental change. Individuals that express plasticity in behavior can quickly respond to changes that occur in the environment. Therefore, individuals that exhibit behavioral plasticity can alter their behavioral expression to best match current environmental conditions. The degree and direction of behavioral plasticity may be influenced by variation in individual characteristics. Understanding how variation in individual traits affects behavioral plasticity, and, whether patterns of behavioral plasticity are consistent across behavioral contexts are important topics to explore as we try to better understand how plasticity evolves and …


Replicability And Reproducibility In Comparative Psychology, Jeffrey R. Stevens May 2017

Replicability And Reproducibility In Comparative Psychology, Jeffrey R. Stevens

Jeffrey Stevens Publications

Psychology faces a replication crisis. The Reproducibility Project: Psychology sought to replicate the effects of 100 psychology studies. Though 97% of the original studies produced statistically significant results, only 36% of the replication studies did so (Open Science Collaboration, 2015). This inability to replicate previously published results, however, is not limited to psychology (Ioannidis, 2005). Replication projects in medicine (Prinz et al., 2011) and behavioral economics (Camerer et al., 2016) resulted in replication rates of 25 and 61%, respectively, and analyses in genetics (Munafò, 2009) and neuroscience (Button et al., 2013) question the validity of studies in those fields. Science, …


Development Of Site Fidelity In The Nocturnal Amblypygid, Phrynus Marginemaculatus, Jacob M. Graving, Verner P. Bingman, Eileen Hebets, Daniel D. Wiegmann Apr 2017

Development Of Site Fidelity In The Nocturnal Amblypygid, Phrynus Marginemaculatus, Jacob M. Graving, Verner P. Bingman, Eileen Hebets, Daniel D. Wiegmann

Eileen Hebets Publications

Amblypygids are capable of navigation in the complex terrain of rainforests in near complete darkness. Path integration is unnecessary for successful homing, and the alternative mechanisms by which they navigate have yet to be elucidated. Here, our aims were to determine whether the amblypygid Phrynus marginemaculatus could be trained to reliably return to a target shelter in a laboratory arena—indicating goal recognition—and to document changes in behavior associated with the development of fidelity. We recorded nocturnal movements and space use by individuals over five nights in an arena in which subjects were provided with two shelters that differed in quality. …


The North American Whistling-Ducks, Pochards, And Stifftails, Paul A. Johnsgard Mar 2017

The North American Whistling-Ducks, Pochards, And Stifftails, Paul A. Johnsgard

Zea E-Books Collection

Although the 12 species representing three waterfowl tribes described in this volume are not closely related, they fortuitously provide an instructive example of adaptive evolutionary radiation within the much larger waterfowl lineage (the family Anatidae), especially as to their divergent morphologies, life histories, and social behaviors.

The whistling-ducks (Dendrocygna), with three known North American species, are notable for their permanent pair-bonds, extended biparental family care, and strong social cohesion. In contrast, males of the five typical pochards of North American diving ducks (Aythya) establish monogamous pair-bonds that are maintained only long enough to assure that the female’s eggs are fertilized. …


Blue Sucker Summer Utilization Distributions And Inter-Annual Fidelity To Summering Habitats, J. David Adams, Casey L. Bergthold, Justin D. Haas, Mark A. Pegg, Gerald E. Mestl Mar 2017

Blue Sucker Summer Utilization Distributions And Inter-Annual Fidelity To Summering Habitats, J. David Adams, Casey L. Bergthold, Justin D. Haas, Mark A. Pegg, Gerald E. Mestl

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Blue Sucker Cycleptus elongatus populations in the Missouri River are believed to be declining. The decline is most likely attributable to anthropogenic modifications including channelization and dam construction. We compared 2008 and 2009 summer use distribution (UD) for 21 blue suckers implanted with acoustic tags to better understand how blue suckers use the Missouri River. UDs are used to analyze space-use requirements based on the home range concept. The geometric mean 95% UD range was 1.9 river kilometers (RKM) in 2008 and 0.3 RKM in 2009, and differed statistically by year. The upper bound of the 2008 95% UD accounted …


Beavers, Jimmy D. Taylor, Greg K. Yarrow, James E. Miller Mar 2017

Beavers, Jimmy D. Taylor, Greg K. Yarrow, James E. Miller

Wildlife Damage Management Technical Series

The American beaver (Castor canadensis) (Figure 1) is known as an “ecosystem engineer” because of the benefits their dams provide to biological diversity and ecosystem function. It also is considered a “keystone species” because of its ability to transform its environment, creating new habitats upon which other species depend. Despite the many positive benefits beavers provide through foraging and dam building, beavers also create conflict with people when their activities cause damage. The authors of this publication acknowledge and appreciate the many positive benefits that beavers provide; however, the focus of this publication is to provide basic information on beaver …


Habitat Selection By The Northern Long-Eared Myotis (Myotis Septentrionalis) In The Midwestern United States: Life In A Shredded Farmscape, Jeremy A. White, Patricia Freeman, Cliff A. Lemen Jan 2017

Habitat Selection By The Northern Long-Eared Myotis (Myotis Septentrionalis) In The Midwestern United States: Life In A Shredded Farmscape, Jeremy A. White, Patricia Freeman, Cliff A. Lemen

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Populations of the Northern Long-Eared Myotis (Myotis septentrionalis) have declined dramatically in recent years in eastern North America due to white-nose syndrome. Although M. septentrionalis was once common in parts of eastern North America, few studies have examined habitat selection of this species in an agricultural landscape. We used acoustical methods to quantify bat activity and construct a habitat model of M. septentrionalis in an intensively farmed area in the Midwestern United States, where mortality from white-nose syndrome has not yet been observed. Our study confirms that M. septentrionalis prefers forest and avoids open habitats in this agricultural …


Cognition-Mediated Evolution Of Low-Quality Floral Nectars, Vladislav Nachev, Kai Petra Stich, Clemens Winter, Alan B. Bond, Alan Kamil, York Winter Jan 2017

Cognition-Mediated Evolution Of Low-Quality Floral Nectars, Vladislav Nachev, Kai Petra Stich, Clemens Winter, Alan B. Bond, Alan Kamil, York Winter

Alan Bond Publications

Plants pollinated by hummingbirds or bats produce dilute nectars even though these animals prefer more concentrated sugar solutions. This mismatch is an unsolved evolutionary paradox. Here we show that lower quality, or more dilute, nectars evolve when the strength of preferring larger quantities or higher qualities of nectar diminishes as magnitudes of the physical stimuli increase. In a virtual evolution experiment conducted in the tropical rainforest, bats visited computer-automated flowers with simulated genomes that evolved relatively dilute nectars. Simulations replicated this evolution only when value functions, which relate the physical stimuli to subjective sensations, were nonlinear. Selection also depended on …


Where Can Wolves Live And How Can We Live With Them?, L. David Mech Jan 2017

Where Can Wolves Live And How Can We Live With Them?, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

In the contiguous 48 United States, southern Canada, and in Europe, wolves (Canis lupus) have greatly increased and expanded their range during the past few decades.They are prolific, disperse long distances, readily recolonize new areas where humans allow them, and are difficult to control when populations become established.Because wolves originally lived nearly everywhere throughout North America and Eurasia, and food in the form of wild and domestic prey is abundant there, many conservation-minded people favor wolves inhabiting even more areas.On the other hand, wolves conflict in several ways with rural residents who prefer fewer wolves. This article discusses …


Review Of Bird Brain: An Exploration Of Avian Intelligence By Nathan Emery, Alan B. Bond Jan 2017

Review Of Bird Brain: An Exploration Of Avian Intelligence By Nathan Emery, Alan B. Bond

Avian Cognition Papers

Over the past 30 years, the study of bird behavior has been completely transformed by the ongoing revolution in cognitive psychology, opening up wholly new perspectives on the mental processes underlying such areas as foraging decisions, social intelligence, problem solving, memory encoding, and communication. Although these studies have contributed to a number of recent popular books, until now there has been no attempt to integrate avian cognition and recent findings in avian neuroanatomy and endocrinology into a single account that is attractive and accessible to a general readership. It is a steep challenge, but Nathan Emery has undertaken it in …


Neural Circuitry For Target Selection And Action Selection In Animal Behavior, Daizaburo Shizuka, Eileen Hebets, Kim L. Hoke Jan 2017

Neural Circuitry For Target Selection And Action Selection In Animal Behavior, Daizaburo Shizuka, Eileen Hebets, Kim L. Hoke

Papers in Behavior in Biological Sciences

Animal behaviorists have long strived for a comprehensive understanding of the proximate and ultimate causes of complex behavior, and we propose that recent advances in neurobiology can help reshape or clarify this behavior-oriented understanding. We begin with an overview of current views of neural circuit mechanisms that mediate target selection and action selection. In target selection, different stimuli compete for priority in sensory-motor process- ing. Action selection is the process by which multiple possible motor actions compete for priority in a manner which balances the needs of the animal with opportunities or threats in the environment. We next discuss spatial …


Increased Insertion Number Leads To Increased Sperm Transfer And Fertilization Success In A Nursery Web Spider, Alissa G. Anderson, Eileen Hebets Jan 2017

Increased Insertion Number Leads To Increased Sperm Transfer And Fertilization Success In A Nursery Web Spider, Alissa G. Anderson, Eileen Hebets

Eileen Hebets Publications

Across animals, a male's fitness is largely dictated by his ability to fertilize eggs; and there exists a plethora of male adaptations associated with increasing fertilization success. In the nursery web spider, Pisaurina mira, males restrain females prior to and during copulation by wrapping them with silk. Previous research demonstrates that copulatory silk wrapping reduces a male's chance of being sexually cannibalized and increases the number of sperm transfer opportunities (termed insertions) that a male can achieve within a mating. While avoiding cannibalism provides an obvious survival benefit to males, the impact of insertion number on male fitness remains …


Importance Of The Antenniform Legs, But Not Vision, For Homing By The Neotropical Whip Spider Paraphrynus Laevifrons, Verner P. Bingman, Jacob M. Graving, Eileen Hebets, Daniel D. Wiegmann Jan 2017

Importance Of The Antenniform Legs, But Not Vision, For Homing By The Neotropical Whip Spider Paraphrynus Laevifrons, Verner P. Bingman, Jacob M. Graving, Eileen Hebets, Daniel D. Wiegmann

Eileen Hebets Publications

Amblypygids, or whip spiders, are nocturnal, predatory arthropods that display a robust ability to navigate to their home refuge. Prior field observations and displacement studies in amblypygids demonstrated an ability to home from distances as far away as 10 m. In the current study, micro-transmitters were used to take morning position fixes of individual Paraphrynus laevifrons following an experimental displacement of 10 m from their home refuge. The intention was to assess the relative importance of vision compared with sensory input acquired from the antenniform legs for navigation as well as other aspects of their spatial behavior. Displaced individuals were …


Record Breaking Achievements By Spiders And The Scientists Who Study Them, Stefano Mammola, Peter Michalik, Eileen Hebets, Marco Isaia Jan 2017

Record Breaking Achievements By Spiders And The Scientists Who Study Them, Stefano Mammola, Peter Michalik, Eileen Hebets, Marco Isaia

Eileen Hebets Publications

Organismal biology has been steadily losing fashion in both formal education and scientific research. Simultaneous with this is an observable decrease in the connection between humans, their environment, and the organisms with which they share the planet. Nonetheless, we propose that organismal biology can facilitate scientific observation, discovery, research, and engagement, especially when the organisms of focus are ubiquitous and charismatic animals such as spiders. Despite being often feared, spiders are mysterious and intriguing, offering a useful foundation for the effective teaching and learning of scientific concepts and processes. In order to provide an entryway for teachers and students—as well …


Intertemporal Choice And Delayed Gratification, Jeffrey R. Stevens Jan 2017

Intertemporal Choice And Delayed Gratification, Jeffrey R. Stevens

Jeffrey Stevens Publications

A parasitoid wasp has deposited half of her eggs in a host. She now faces the choice between depositing her remaining eggs in the same host or searching for another. Continuing to deposit in the current host provides the immediate payoff of completing her reproductive duties, allowing her to move on to other activities such as foraging or searching for another mate. Searching for another host, in contrast, delays the payoffs of reproducing until a suitable host is found. This wasp faces an intertemporal choice—that is, a choice between options that involve payoffs available at different times (Read, 2004; Stevens, …


Sandhill And Whooping Cranes, Jeb Barzen, Ken Ballinger Jan 2017

Sandhill And Whooping Cranes, Jeb Barzen, Ken Ballinger

Wildlife Damage Management Technical Series

As sandhill crane populations continue to grow in the United States, so too does crop damage, property damage to homeowners, and the risk of crane collisions with aircraft. Whooping crane populations also continue to grow, but with a global population of about 500 individuals (as of 2017), damage is rare and problems often require different solutions due to the species’ endangered status. The behavioral characteristics and habitat needs of sandhill and whooping cranes set the stage for conflict between these birds and people. Recognizing behavioral differences between territorial and non-territorial cranes greatly improves the effectiveness of any management effort.

Human-Wildlife …


Wildlife At Airports, Travis L. Devault, Bradley F. Blackwell, Jerrold L. Belant, Michael J. Begier Jan 2017

Wildlife At Airports, Travis L. Devault, Bradley F. Blackwell, Jerrold L. Belant, Michael J. Begier

Wildlife Damage Management Technical Series

Collisions between aircraft and wildlife (wildlife strikes) are common occurrences across the developed world. Wildlife strikes are not only numerous, but also costly. Estimates suggest that wildlife strikes cost the civil aviation industry in the U.S. up to $625 million annually, and nearly 500 people have been killed in wildlife strikes worldwide. Most wildlife strikes occur in the airport environment: 72 percent of all strikes occur when the aircraft is ≤500 ft (152 m) above ground level, and 41 percent of strikes occur when the aircraft is on the ground during landing or takeoff. Thus, management efforts to reduce wildlife …


Phytophagous Insect Oviposition Shifts In Response To Probability Of Flower Abortion Owing To The Presence Of Basal Fruits, Shivani Jadeja, Brigitte Tenhumberg Jan 2017

Phytophagous Insect Oviposition Shifts In Response To Probability Of Flower Abortion Owing To The Presence Of Basal Fruits, Shivani Jadeja, Brigitte Tenhumberg

School of Biological Sciences: Faculty Publications

Phytophagous insects use a wide range of indicators or associated cues to avoid laying eggs in sites where offspring survival is low. For insects that lay eggs in flowers, these unsuitable sites may be created by the host plant’s resource allocation to flowers. In the sequentially flowering host plant, Yucca glauca, late-opening distal flowers are more likely to be aborted in the presence of already-initiated basal fruits because they are strong resource sinks. If flowers are aborted, all eggs of the phytophagous insect, Tegeticula yuccasella, within the flower die. We used the phytophagous insect T. yuccasella that lays …


A Serosurvey Of Diseases Of Free-Ranging Gray Wolves (Canis Lupus) In Minnesota, Usa, Michelle Carstensen, John H. Giudice, Erik C. Hildebrand, J. P. Dubey, John Erb, Dan Stark, John Hart, Shannon M. Barber-Meyer, L. David Mech, Steve K. Windels, Andrew J. Edwards Jan 2017

A Serosurvey Of Diseases Of Free-Ranging Gray Wolves (Canis Lupus) In Minnesota, Usa, Michelle Carstensen, John H. Giudice, Erik C. Hildebrand, J. P. Dubey, John Erb, Dan Stark, John Hart, Shannon M. Barber-Meyer, L. David Mech, Steve K. Windels, Andrew J. Edwards

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

We tested serum samples from 387 free-ranging wolves (Canis lupus) from 2007 to 2013 for exposure to eight canid pathogens to establish baseline data on disease prevalence and spatial distribution in Minnesota’s wolf population. We found high exposure to canine adenoviruses 1 and 2 (88% adults, 45% pups), canine parvovirus (82% adults, 24% pups), and Lyme disease (76% adults, 39% pups). Sixty-six percent of adults and 36% of pups exhibited exposure to the protozoan parasite Neospora caninum. Exposure to arboviruses was confirmed, including West Nile virus (37% adults, 18% pups) and eastern equine encephalitis (3% adults). Exposure rates …


Changes In Male Hunting Returns, Raymond B. Hames Dec 2016

Changes In Male Hunting Returns, Raymond B. Hames

Department of Anthropology: Faculty Publications

Research on changes in male hunting among hunter-gatherers addresses two important issues in early human evolution: the nature of the family and trade-offs in mating and parenting effort as well as the development of embodied capital. In the hunter-gatherer literature, there is a debate about the function of male hunting that has implications for understanding the role males play in the evolution of the pair bond. The traditional model argues that male hunting and other economic activities are forms of male provisioning or parenting effort designed to enhance a man’s fitness through his wife’s reproduction and the survivorship of their …


Distribution, Abundance, And Migration Timing Of Greater And Lesser Sandhill Cranes Wintering In The Sacramento–San Joaquin River Delta Region Of California, Gary L. Ivey, Bruce D. Dugger, Caroline P. Herziger, Michael L. Casazza, Joseph P. Fleskes Dec 2016

Distribution, Abundance, And Migration Timing Of Greater And Lesser Sandhill Cranes Wintering In The Sacramento–San Joaquin River Delta Region Of California, Gary L. Ivey, Bruce D. Dugger, Caroline P. Herziger, Michael L. Casazza, Joseph P. Fleskes

Proceedings of the North American Crane Workshop

The Sacramento-San Joaquin River Delta region of California (hereafter, Delta region) is an important wintering region for the Central Valley Population of greater sandhill cranes (Grus canadensis tabida) and lesser sandhill cranes (G. c. canadensis), but basic information about the ecology of these birds is lacking to design a biologically sound conservation strategy. During the winters of 2007-08 and 2008-09, we conducted roost counts, roadside surveys, aerial surveys, and tracked radio-marked birds to define the geographic area used by sandhill cranes in the Delta region, document migration chronology, and estimate subspecies-specific abundance. Radio-marked sandhill cranes arrived in our study area …


Sandhill Crane Roost Selection, Human Disturbance, And Forage Resources, Aaron T. Pearse, Gary L. Krapu, David A. Brandt Nov 2016

Sandhill Crane Roost Selection, Human Disturbance, And Forage Resources, Aaron T. Pearse, Gary L. Krapu, David A. Brandt

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Sites used for roosting represent a key habitat requirement for many species of birds because availability and quality of roost sites can influence individual fitness. Birds select roost sites based on numerous factors, requirements, and motivations, and selection of roosts can be dynamic in time and space because of various ecological and environmental influences. For sandhill cranes (Antigone canadensis) at their main spring staging area along the Platte River in south-central Nebraska, USA, past investigations of roosting cranes focuse donphysical channel characteristics related to perceived security as motivating roost distribution.We used 6,310 roost sites selected by 313 sandhill cranes over …


Monk Parakeets, Michael L. Avery, James R. Lindsay Nov 2016

Monk Parakeets, Michael L. Avery, James R. Lindsay

Wildlife Damage Management Technical Series

Since their introduction to the United States in the 1960s, monk parakeets (Myiopsitta monachus) have thrived (Figure 1). Until recently, annual Christmas Bird Count data have shown the population to be increasing exponentially. In the U.S., monk parakeets are an urban and suburban species with few natural predators, diseases or other factors limiting their population growth. They exploit backyard bird feeders and non-native ornamental plants for food. Monk parakeets often construct nests on man-made structures, such as electric utility facilities and cell phone towers. Because the birds build and maintain nests throughout the year, management of parakeet populations …


Inter- And Intra-Individual Variation In Predator-Related Behavioral Plasticity Expressed By Female Green Swordtails (Xiphophorus Hellerii), Rachael A. Disciullo Nov 2016

Inter- And Intra-Individual Variation In Predator-Related Behavioral Plasticity Expressed By Female Green Swordtails (Xiphophorus Hellerii), Rachael A. Disciullo

School of Biological Sciences: Dissertations, Theses, and Student Research

Phenotypic plasticity is the ability of one genotype to express multiple phenotypes under variable environments. Behavioral plasticity is a type of phenotypic plasticity in which individuals adjust behavior in response to changes in environment. Often, behavioral plasticity is studied at the level of the population, rather than at the level of the individual. Further, few studies have considered the effect of individual traits, such as size and age, on the expression of behavioral plasticity, or, how individual plasticity may be correlated across different contexts. In this study, we used female green swordtails (Xiphophorus hellerii) to test the effects …


Cedar Waxwings, Michael L. Avery, Anthony G. Duffiney Oct 2016

Cedar Waxwings, Michael L. Avery, Anthony G. Duffiney

Wildlife Damage Management Technical Series

Prevention and control of cedar waxwing (Bombycilla cedrorum) damage to small fruits such as blueberry, cherry, and strawberry is vexing to growers in many parts of the United States. Cedar waxwings (Figure 1) travel in flocks and descend in large numbers on berry crops, especially during winter and migration. In short feeding bouts, waxwings eat, peck, or knock substantial amounts of fruit from the plants. These frugivores are difficult to discourage once they become established at a given location. Harassment early and often using pyrotechnics or other sudden noisemakers can help prevent flocks from being established. The most effective preventative …


Polyandry In The Absence Of Fitness Benefits In A Species With Female-Biased Sexual Size Dimorphism, Marie Claire Chelini, Eileen A. Hebets Aug 2016

Polyandry In The Absence Of Fitness Benefits In A Species With Female-Biased Sexual Size Dimorphism, Marie Claire Chelini, Eileen A. Hebets

Eileen Hebets Publications

Most studies exploring the evolution of female mating systems focus on species in which females are either monandric (mate with a single male) or highly polyandric (mate with multiple males), but less is understood about variation in mating decisions within a species. How and why do females of a single species decide whether or not to copulate with additional mates? In this study we attempt to answer this question in the highly dimorphic crab spider, Mecaphesa celer, whose females may be either monandric or polyandric. We tested three hypotheses: (1) a female’s decision to remate is based on sequential mate …


Blackbirds, Richard A. Dolbeer, George M. Linz Aug 2016

Blackbirds, Richard A. Dolbeer, George M. Linz

Wildlife Damage Management Technical Series

The term blackbird loosely refers to a diverse group of about 10 species of North American birds that belong to the avian family Icteridae. The most common species include: Red-winged blackbird (Agelaius phoeniceus) Common grackle (Quiscalus quiscula) Great-tailed grackle (Quiscalus mexicanus) Brown-headed cowbird (Molothrus ater) Yellow-headed blackbird (Xanthocephalus xanthocephalus) Brewer’s blackbird (Euphagus cyanocephalus) Rusty blackbird (Euphagus carolinus) In addition to blackbirds, this family includes orioles, meadowlarks, and bobolinks.

Human-Wildlife Conflicts 1 Damage Identification 3 Management Methods 4 Economics 7 Species Overview 8 Legal Status 11 Glossary …


Double-Crested Cormorants, Brian S. Dorr, Kristi L. Sullivan, Paul D. Curtis, Richard Chipman, Russell D. Mccullough Aug 2016

Double-Crested Cormorants, Brian S. Dorr, Kristi L. Sullivan, Paul D. Curtis, Richard Chipman, Russell D. Mccullough

Wildlife Damage Management Technical Series

The history of conflict between double-crested cormorants (Figure 1) and human interest in fisheries is long and convoluted. Following a low point in the 1970s, populations of cormorants expanded in North America, as did concerns about impacts on fisheries. By the late 1990s, natural resource agencies in 27 states reported losses of free-ranging fish stocks to cormorants. Agencies in 10 states, ranging from the Southwest to the Northeast, considered cormorant predation to be of moderate to major concern to fishery management.

Overall, double-crested cormorants are not major consumers of commercial and sportfish species. However, exceptions have been recorded at specific …


Bird Dispersal Techniques, Thomas W. Seamans, Allen L. Gosser Aug 2016

Bird Dispersal Techniques, Thomas W. Seamans, Allen L. Gosser

Wildlife Damage Management Technical Series

Conflicts between humans and birds likely have existed since agricultural practices began. Paintings from ancient Greek, Egyptian, and Roman civilizations depict birds attacking crops. In Great Britain, recording of efforts at reducing bird damage began in the 1400s, with books on bird control written in the 1600s. Even so, the problem persists. Avian damage to crops remains an issue today, but we also are concerned with damage to homes, businesses, and aircraft, and the possibility of disease transmission from birds to humans or livestock. Successful dispersal techniques should capitalize on bird sensory capabilities. If birds cannot perceive the dispersal technique, …