Ecology and Evolutionary Biology Commons^™

Mercury Reduces Avian Reproductive Success And Imposes Selection: An Experimental Study With Adult- Or Lifetime-Exposure In Zebra Finch, Claire W. Varian-Ramos, John P. Swaddle, Daniel A. Cristol

Daniel Cristol

Mercury is a global pollutant that biomagnifies in food webs, placing wildlife at risk of reduced reproductive fitness and survival. Songbirds are the most diverse branch of the avian evolutionary tree; many are suffering persistent and serious population declines and we know that songbirds are frequently exposed to mercury pollution. Our objective was to determine the effects of environmentally relevant doses of mercury on reproductive success of songbirds exposed throughout their lives or only as adults. The two modes of exposure simulated philopatric species versus dispersive species, and are particularly relevant because of the heightened mercury-sensitivity of developing nervous systems. …

Reproductive Success Of Eastern Bluebirds (Siala Sialis) On Suburban Golf Courses, Kerri L. Cornell, Caitlin R. Kight, Ryan B. Burdge, Alex R. Gunderson, Joanna K. Hubbard, Allyson K. Jackson, Joshua E. Leclerc, Marie L. Pitts, John P. Swaddle, Daniel A. Cristol

Daniel Cristol

Understanding the role of green space in urban—suburban landscapes is becoming critical for bird conservation because of rampant habitat loss and conversion. Although not natural habitat, golf courses could play a role in bird conservation if they support breeding populations of some native species, yet scientists remain skeptical. In 2003–2009, we measured reproduction of Eastern Bluebirds (Siala sialis) in Virginia on golf courses and surrounding reference habitats, of the type that would have been present had golf courses not been developed on these sites (e.g., recreational parks, cemeteries, agriculture land, and college campus). We monitored >650 nest boxes …

Blood Mercury Levels Of Zebra Finches Are Heritable: Implications For The Evolution Of Mercury Resistance, Kenton A. Buck, Claire W. Varian-Ramos, Daniel A. Cristol, John P. Swaddle

Daniel Cristol

Mercury is a ubiquitous metal contaminant that negatively impacts reproduction of wildlife and has many other sub-lethal effects. Songbirds are sensitive bioindicators of mercury toxicity and may suffer population declines as a result of mercury pollution. Current predictions of mercury accumulation and biomagnification often overlook possible genetic variation in mercury uptake and elimination within species and the potential for evolution in affected populations. We conducted a study of dietary mercury exposure in a model songbird species, maintaining a breeding population of zebra finches (Taeniopygia guttata) on standardized diets ranging from 0.0–2.4 μg/g methylmercury. We applied a quantitative genetics …

A Sonic Net Excludes Birds From An Airfield: Implications For Reducing Bird Strike And Crop Losses, John P. Swaddle, Dana L. Moseley, Mark H. Hinders, Elizabeth P. Smith

John Swaddle

Collisions between birds and aircraft cause billions of dollars of damages annually to civil, commercial, and military aviation. Yet technology to reduce bird strike is not generally effective, especially over longer time periods. Previous information from our lab indicated that filling an area with acoustic noise, which masks important communication channels for birds, can displace European Starlings (Sturnus vulgaris) from food sources. Here we deployed a spatially controlled noise (termed a “sonic net”), designed to overlap with the frequency range of bird vocalizations, at an airfield. By conducting point counts, we monitored the presence of birds for four weeks before …

Acoustic Space Is Affected By Anthropogenic Habitat Features: Implications For Avian Vocal Communication, Caitlin R. Kight, Mark H. Hinders, John P. Swaddle

John Swaddle

Human-altered landscapes often include structural features, such as higher levels of impervious surface cover (ISC) and less vegetation, that are likely to affect the transmission of avian vocalizations. We investigated the relationships between human habitat modifications and signal transmission by measuring four acoustic parameters—persistence, reverberation, and signal-to-noise ratio (SNR) of broadcast tones, as well as absolute ambient noise level—in each of 39 avian breeding territories across an anthropogenic disturbance gradient. Using a geographic information system, we quantified the amounts of different habitat features (e.g., ISC, grass, trees) at each site; a principal component analysis was used to identify which of …

Blood Mercury Levels Of Zebra Finches Are Heritable: Implications For The Evolution Of Mercury Resistance, Kenton A. Buck, Claire W. Varian-Ramos, Daniel A. Cristol, John P. Swaddle

John Swaddle

Mercury is a ubiquitous metal contaminant that negatively impacts reproduction of wildlife and has many other sub-lethal effects. Songbirds are sensitive bioindicators of mercury toxicity and may suffer population declines as a result of mercury pollution. Current predictions of mercury accumulation and biomagnification often overlook possible genetic variation in mercury uptake and elimination within species and the potential for evolution in affected populations. We conducted a study of dietary mercury exposure in a model songbird species, maintaining a breeding population of zebra finches (Taeniopygia guttata) on standardized diets ranging from 0.0–2.4 μg/g methylmercury. We applied a quantitative genetics …

Reproductive Success Of Eastern Bluebirds (Siala Sialis) On Suburban Golf Courses, Kerri L. Cornell, Caitlin R. Kight, Ryan B. Burdge, Alex R. Gunderson, Joanna K. Hubbard, Allyson K. Jackson, Joshua E. Leclerc, Marie L. Pitts, John P. Swaddle, Daniel A. Cristol

John Swaddle

Understanding the role of green space in urban—suburban landscapes is becoming critical for bird conservation because of rampant habitat loss and conversion. Although not natural habitat, golf courses could play a role in bird conservation if they support breeding populations of some native species, yet scientists remain skeptical. In 2003–2009, we measured reproduction of Eastern Bluebirds (Siala sialis) in Virginia on golf courses and surrounding reference habitats, of the type that would have been present had golf courses not been developed on these sites (e.g., recreational parks, cemeteries, agriculture land, and college campus). We monitored >650 nest boxes …

Density, Abundance, And Habitat Associations Of The Inland Swamp Sparrow (Melospiza Georgiana Georgiana) In Iowa, Tyler Harms, Stephen Dinsmore

Tyler Harms

Wetlands continue to decline throughout North America and the Prairie Pothole Region, thus emphasizing the importance of understanding population trends and habitat associations of wetland species to ensure effective conservation and habitat management of those species. We estimated density and abundance and evaluated habitat associations of the Inland Swamp Sparrow (Melospiza georgiana georgiana) in Iowa. We conducted standardized distance sampling surveys for Swamp Sparrows and measured habitat characteristics at 307 wetlands in two regions of Iowa in 2009 and 2010. We used Program Distance to model detection probability and estimate region-specific breeding densities of Swamp Sparrows at Iowa …

Density And Abundance Of Secretive Marsh Birds In Iowa, Tyler Harms, Stephen Dinsmore

Tyler Harms

A decrease in wetland habitats throughout North America has caused a decline in populations of marsh birds. The objective of this study was to estimate population densities and abundances of secretive marsh birds in Iowa. Call-broadcast surveys were conducted in conjunction with distance sampling for eight species of marsh birds at wetlands in three regions of Iowa during 2009 and 2010. Regions were defined by observed microhabitat characteristics which also corresponded to physiographic regions. Region-specific density estimates were obtained using Program Distance for four species of marsh birds for which sufficient detections existed (Pied-billed Grebe [Podilymbus podiceps], Least …

Wintering Ecology Of Adult North American Ospreys, Brian E. Washburn, Charles J. Henny, Mark S. Martell, Richard O. Bierregaard, Brian S. Dorr, Thomas J. Olexa

Brian S Dorr

North American Ospreys (Pandion haliaetus) typically migrate long distances to their wintering grounds in the tropics. Beyond the general distribution of their wintering range (i.e., the Caribbean, South America, and Central America), very little is known about the wintering ecology of these birds. We used satellite telemetry to determine the duration of wintering period, to examine the characteristics of wintering areas used by Ospreys, and to quantify space use and activity patterns of wintering Ospreys. Adult Ospreys migrated to wintering sites and exhibited high wintering site fidelity among years. Overall, Ospreys wintered on river systems (50.6%) more than on lakes …

Geographic Segregation And Evidence Of Density-Dependent Changes In Sex Ratios In An Abundant Colonial Waterbird, Brian S. Dorr, Katie C. Hanson-Dorr, Travis L. Devault, Alban Guillaumet, Scott C. Barras

Brian S Dorr

Demographic information, such as geographic segregation of sexes and sex ratio data, is needed to develop, model and evaluate conservation and management strategies for wildlife. A variety of physiological, behavioral and environmental factors can influence segregation of sexes and sex ratios, many of which originate with density- dependent processes. Departure from 50:50 sex ratios of double-crested cormorants (Phalacrocorax auritus) collected during control efforts in breeding and wintering areas across their eastern range of the USA were evaluated using using a Z-test as well as Stouffer’s weighted Z-tests. In addition, a specifically-designed randomization test was used to evaluate density-dependent effects on …

Next-Generation Field Guides, Elizabeth J. Farnsworth, Miyoko Chu, W. John Kress, Amanda K. Neill, Jason H. Best, John Pickering, Robert D. Stevenson, Gregory W. Courtney, John K. Vandyk, Aaron M. Ellison

John K. VanDyk

To conserve species, we must first identify them. Field researchers, land managers, educators, and citizen scientists need up-to-date and accessible tools to identify organisms, organize data, and share observations. Emerging technologies complement traditional, book-form field guides by providing users with a wealth of multimedia data. We review technical innovations of next-generation field guides, including Web-based and stand-alone applications, interactive multiple-access keys, visual-recognition software adapted to identify organisms, species checklists that can be customized to particular sites, online communities in which people share species observations, and the use of crowdsourced data to refine machine-based identification algorithms. Next-generation field guides are user …

A Global Analysis Of The Impacts Of Urbanization On Bird And Plant Diversity Reveals Key Anthropogenic Drivers, Myla F.J. Aronson, Frank A. La Sorte, Charles H. Nilon, Madhusudan Katti, Mark A. Goddard, Christopher A. Lepczyk, Paige S. Warren, Nicholas S.G. Williams, Sarel Cilliers, Bruce Clarkson, Cynnamon Dobbs, Rebecca W. Dolan, Marcus Hedblom, Stefan Klotz, Jip Louwe Kooijmans, Ingolf Kühn, Ian Macgregor-Fors, Mark Mcdonnell, Ulla Mörtberg, Petr Pyšek, Stefan Siebert, Jessica Sushinsky, Peter Werner, Marten Winter

Rebecca W. Dolan

Urbanization contributes to the loss of the world's biodiversity and the homogenization of its biota. However, comparative studies of urban biodiversity leading to robust generalities of the status and drivers of biodiversity in cities at the global scale are lacking. Here, we compiled the largest global dataset to date of two diverse taxa in cities: birds (54 cities) and plants (110 cities). We found that the majority of urban bird and plant species are native in the world's cities. Few plants and birds are cosmopolitan, the most common beingColumba livia and Poa annua. The density of bird and plant species …

Habitat Characteristics Of Mexican Spotted Owls (Strix Occidentalis Lucida) In The Canyonlands Of Southern Utah, Leah Lewis

Leah R Lewis

I studied the habitat characteristics of Mexican Spotted Owls (Strix occidentalis lucida), a federally threatened species, in the canyonlands region of southern Utah. Vegetative and geologic features were measured within 10m wide belt plots at each current or historic nest/roost site. Based on our findings, past research, and species life history characteristics, I constructed a species distribution model (SDM) predicting Mexican Spotted Owl distribution in Utah for the Colorado Plateau region. The SDM was generated using the following inputs as important habitat variables: elevation, aspect, surface ratio, curvature, slope, geology, and vegetation. Program R was used for model development and …

Modeling Parasitism Rate And Parasitism Risk: An Illustration Using A Colonially Nesting Songbird, The Red-Winged Blackbird Agelaius Phoeniceus, Max Post Van Der Burg, Larkin A. Powell, Andrew J. Tyre

Andrew J Tyre

Ornithologists interested in the drivers of nest success and brood parasitism benefit from the development of new analytical approaches. One example is the development of so-called “log exposure” models for analyzing nest success. However, analyses of brood parasitism data have not kept pace with developments in nest success analyses. The standard approach uses logistic regression which does not account for multiple parasitism events, nor does it prevent bias from using observed proportions of parasitized nests. Likewise, logistic regression analyses do not capture fine scale temporal variation in parasitism. At first glance, it might be tempting to apply log exposure models …

Influence Of Latitude On The Winter Abundance Of Red-Tailed Hawks (Buteo Jamaicensis) And American Kestrels (Falco Sparverius) In Illinois, Given Harper, Anna Groves, Vic Berardi, Paul Sweet, Jance Sweet, Angelo P. Capparella

Given Harper

A Guide To The Tallgrass Prairies Of Eastern Nebraska And Adjacent States, Paul A. Johnsgard

Paul Johnsgard

Contents Part 1: Ecology of the Tallgrass Prairie Part 2: Plants of the Tallgrass Prairies: Checklist of Prairie & Grassland Plants of Nebraska; Relative Frequencies of Grasses, Spring Creek and Nine-mile Prairies; Twenty Most Abundant Fall Forbs, Spring Creek and Nine-mile Prairies; Typical Shrubs, Forbs, Grasses & Sedges of Eastern Nebraska Tallgrass Prairies; English: Latin Name Equivalents of 370 Tallgrass Prairie Plants; Latin: English Name Equivalents of 370 Tallgrass Prairie Plants Identification Keys to Some Common Nebraska Grassland Forbs Part 3: Animals of the Tallgrass Prairies Greater Prairie-chickens and Native Prairies; Seasonal Checklist of Nebraska Tallgrass Ecoregion Birds (Gage County); …

The Ivory-Billed Woodpecker In Mississippi?, Stephen J. Dinsmore

Stephen J Dinsmore

In April the environmental community received a real surprise--the Ivory-billed Woodpecker, long thought to be extinct, had apparently been rediscovered in Arkansas! As the news unfolded, the world learned that a team of researchers had been tracking at least one woodpecker, a lone male, for more than a year in the Cache River region of east-central Arkansas. The rediscovery of a bird presumed extinct for more than 60 years subsequently galvanized the environmental community and garnered much-needed support for the preservation of the Southeast's remaining old growth bottomland forests and endangered species recovery.

Waterfowl Abundance And Distribution In The Mississippi Delta, Stephen J. Dinsmore, Aaron T. Pearse, Richard M. Kaminski, Kenneth J. Reinecke

Stephen J Dinsmore

During mornings of empty skies, a duck hunter has plenty of time to ponder the question, "Where are all the ducks?" Invariable, the distraught hunter arrives at an unhappy conclusion: the ducks are not going to show up, so they must be elsewhere. The typical progression of an unsuccessful morning of hunting leads to multiple explanations as to why there weren't any ducks, such as mild winter temperatures in and north of Mississippi, not enough rain to attract ducks, too much rain and the ducks are scattered, the region doesn't have enough food to attract and hold ducks, the ducks …

Avian Prey-Dropping Behavior. I. The Effects Of Prey Characteristics And Prey Loss, Paul V. Switzer, Daniel A. Cristol

Paul V. Switzer

No abstract provided.

Crows Do Not Use Automobiles As Nutcrackers: Putting An Oft-Repeated Anecdote To The Test, Daniel A. Cristol, Paul V. Switzer, K L. Johnson, L S. Walke

Paul V. Switzer

No abstract provided.

Capsaicin Effects On Consumption Of Food By Cedar Waxwings And House Finches.­, Donald Norman, Russell Mason, Larry Clark

Larry Clark

Capsaicin effects on consumption of food by Cedar Waxwings and House Finches.­ Capsaicinoids (e.g., N-vanillyl-n-nonamide. norcapsaicin, nordihydrocapsaicin, capsaicin, dihydrocapsaicin, homocapsaicin, homodihydrocapsaicin; Hoffman 1983) are aromatic am­ ides and the pungent principles in Capsicum peppers. Although these substances are strong chemical irritants for most mammals (e.g.. Rozin et a!. 1979), the available data suggest that they are inoffensive to some birds. For example. European Starlings (Sturn us vulgaris) and Rock Doves (Columba Iivia) are unresponsive to these compounds, even when con­ centrations greatly exceed those which mammals avoid (Szolcsanyi et al. 1986; Mason et a!.. in press).

Thermal Constraints On Foraging Activity Of Adult Starlings, Larry Clark

Larry Clark

The operative temperature of the environment was estimated for starlings using hollow, unheated taxidermic mounts. On average, adults foraging in full sun were characterized by shorter foraging bouts than those adults foraging in full shade. Simultaneous observations of air temperature, operative temperature, and the foraging duration of adults indicated that air temperature was a poor predictor of the maximum length of a foraging bout. The operative temperature of the environment was not correlated to the maximum and mean length of foraging bouts for temperatures below 31.5 ~ C, but was negatively related to maximum and mean foraging duration for values …

Olfactory Discrimination Of Plant Volatiles By The European Starling, Larry Clark, J Russell Mason

Larry Clark

Passerine species that re-use nest sites often incorporate fresh green vegetation into their nests, a behaviour consistent with the possibility that some birds may use chemical properties of plants to counteract the selective potential of parasites and pathogens. We tested adult starlings (Sturnus vulgaris) for their physiological capacity and behavioural ability to detect and discriminate between volatiles emitted from plant material. Multi-unit electrophysiological recordings from olfactory nerves of adults indicated that strong responses were reliably elicited by volatiles from six plant species. After pairings of plant volatiles with gastro-intestinal malaise, birds exhibited conditioned avoidance in behavioural experiments, and made all …