Prêmios de Apresentação por Alunos

O AFO tem o orgulho de reconhecer as melhores apresentações dos alunos em nossas reuniões anuais. Para ser considerado para um prêmio de apresentação, veja os critérios listados no site da reunião a cada ano.

 Award Winners:

*em breve*

Congratulations to the following students who received presentation awards at the 2013 AFO meeting at Archbold Biological Station in Venus, Florida.

Best Oral Presentations

BLAKE JONES, University of Memphis, “Stress response correlates  with learned antipredator behavior in free-living Florida Scrub-Jays (Aphelocoma coerulescens).”

Blake Jones

The extent to which animals learn and retain information about predators, and the mechanisms that mediate these processes, remain largely unexplored. Corticosterone (CORT), the avian glucocorticoid, is released in response to stressful stimuli, including perception of a predator. Elevated CORT facilitates physiological and behavioral changes over the short-term that can enhance survival and, over the long-term, can a/ect memory function. 0us, CORT is a likely candidate to mediate learned antipredator behavior. Florida Scrub-Jays (FSJ) exhibit intraspeci.c variation of stress induced plasma CORT levels, which are repeatable within individuals. We used the FSJ as a model to test two hypotheses: 1) FSJs have the capacity to learn antipredator behavior and 2) CORT responsiveness is predictive of antipredator behavior. We developed a model to test for, and compare CORT responsiveness to, learned antipredator behavior in free-living FSJs. Compared to control birds, Individuals who were previously exposed to an arti.cial novel “predator” displayed longer flight initiation distances (FID) and alarm called more frequently in response to the novel “predator.” Also, CORT responsiveness was positively correlated with FID. These data indicate FSJs can learn to associate a novel “predator” stimulus as a threat after a single exposure, and that stress physiology is related to this cognitive process.

MARJORIE LIBERATI , Ohio State University (Co-author: Dr. Robert Gates), “Habitat selection and nesting ecology of Northern Bobwhite in Ohio.”

Mauri Liberati

Local abundance of breeding Northern Bobwhites (Colinus virginianus) has increased with grasslands created through the Conservation Reserve Program but positive range-wide population growth has not occurred. Ohio’s bobwhite population experienced a 90% population decline after severe winters in 1976–1977 and 1977–1978 and populations continued at a 76% decline during 1984–2004. Radio-marked adult bobwhites were monitored during the breeding season (1 May –30 Sep, 2010–2011) on four private-lands study sites located in southwest Ohio. Eighty-six percent of nests (n = 52) were located in grassland habitats. Nest success was 27.9% and daily nest survival (96.9%) was not in2uenced by nesting habitat, nest initiation date, year, or study site. Row crop was the most abundant habitat type (41%) within breeding season home range areas, but was generally avoided. Early successional (ES) woody habitat (e.g., fencerows and ditches) was the most highly selected habitat type at all spatial scales. Grassland habitat was th e next most selected habitat type. Selection of forest and ES woody habitats diminished at study sites where these habitats had mature canopies and poorly developed understories. Future bobwhite management strategies should focus on providing more ES woody cover within landscapes because it can provide year-round bene.ts. Continuing to providing grassland habitat for bobwhites during the breeding season should not be abandoned due to its lower selection ranking because it provides important nesting habitat. Providing proximate ES woody cover near grasslands would enhance breeding habitat quality for bobwhites in Ohio and other areas of the Midwestern United States.

 Best Poster Presentation

MOLLY GRACE, University of Central Florida (Co-author: Dr. Rindy Anderson), “Songbirds’ acoustically complex notes may facilitate communication in noisy urban areas.”

Molly GraceIn an increasingly urban world, noise pollution creates communication challenges for wildlife. Loud, low-frequency traffic noise can mask songbird vocalizations, and populations of some urban songbird species have shifted the frequency of their vocalizations upward in response, which is energetically costly. However, acoustically complex notes have a quasi-harmonic frequency structure that may make them resistant to masking, suggesting that species that use them could be more successful in areas with high levels of traffic noise. Based on this idea, we hypothesized that complex notes are not produced at higher frequencies in response to traffic noise. We recorded Carolina Chickadees (Poecile carolinensis), whose calls feature complex ‘D’ notes, along a traffic noise gradient in Durham and Orange Counties, North Carolina, USA. There was no correlation between the frequency of ‘D’ notes and the level of noise in which they were recorded, implying that a frequency shift is not required for complex notes to be communicated in noise. Understanding how complex notes are affected by traffic noise will increase our ability to predict how the expansion of noisy areas may impact songbird community composition in the future.

Congratulations to the following students who received presentation awards at the 2012 NAOC meeting in Vancouver, B.C., Canada.

Best Oral Presentation
LEONARDO CALLE, M.S. Candidate, Florida Atlantic University (Advisor: Dr. Dale Gawlick), “Predicted changes in foraging habitat of the Little Blue Heron.”

Leonardo CalleWading birds are restricted to feeding in shallow water because of their leg-length constraint, making them sensitive to small changes in water depth. In coastal systems, this sensitivity is pronounced because tidal fluctuations control both the spatial and temporal extent of available foraging habitat. Our objective was to determine the risk of the Little Blue Heron (Egretta caerulea) to sea level rise within the boundaries of the Great White Heron National Wildlife Refuge, in the Florida Keys, USA. Our approach to the problem was to develop a tide-driven simulation model to estimate foraging habitat availability (FHA). The FHA model incorporated fine-scale information on water depths used by the Little Blue Heron, predicted changes in habitat availability from the Sea Level Rise and Accretion Model, under 3 sea level rise scenarios. We validated the model’s ability to predict available foraging habitat using locations of foraging Little Blue Herons (N=509) observed during 14 surveys (Dec 2010–Jul 2011). Parameters to which the model was most sensitive were foraging water depth window, tide height, and the time of low tide, respectively. The model performed moderately well (78% correct classification using survey-specific FHA estimates) to very well (94% correct classification using mean annual FHA estimates) at predicting available foraging habitat. The majority (57%) of Little Blue Herons foraged at areas with tide-specific FHA values of >7 hectare-minutes. Under all three sea level rise scenarios daily foraging habitat declined, with the most severe declines occurring between 2050 and 2075. Our results may be liberal because we excluded mangrove islands as foraging habitat. We suspect that as mangrove habitats become inundated for longer periods of time they will become suitable foraging areas, if they are not already. The fine temporal scale of the FHA model (from a single-tide to ays, months) makes it potentially useful for addressing short- and longterm stressors to multiple wading bird species resulting from human disturbance or sea level rise. However, the sensitivity of the model to very small changes in tide height underscore the importance of having improved estimates of sea level rise at the local level.

Best Poster Presentation
KATHARINE BATDORF, M.S. Candidate, The Ohio State University (Advisors: Paul Rodewald & Stephen Matthews), “Are all birds moving poleward? Understanding distributional shifts in Ohio’s breeding birds.”

Kate BatdorfResearch on the effects of environmental changes on avian distributions is essential in predicting, managing, and conserving bird populations. Several recent studies have reported poleward shifts in bird distributions which are likely associated with a warming climate. However, only a few such studies have used fine-scaled regional data such as that generated by Breeding Bird Atlas projects, only one of which is from North America (New York State). The American Midwest presents different species assemblages and landscapes relative to these previous studies. Our study provides an opportunity to test whether poleward trends in avian distributions observed in other regions transcend these ecological differences. We used detailed grid-based data collected during two Ohio Breeding Bird Atlas projects (1982–1987, 2006–2011) to quantify changes in latitudinal extent, center of occurrence, and occupancy in 94 species within Ohio over ~25 years. Individual species demonstrated dramatic latitudinal changes in their distributions, with the centers of occurrence of 53% of species examined shifting north or south by more than 10km. Despite these results, our analyses did not show a significant poleward shift in distributions across species, although, on average, northern extent and center of occurrence of southerly species did shift north by 4.6km and 8.6km, respectively (p>0.10). Additionally, we found evidence of southward shifts in northerly species, with southern extents and center of occurrence shifting on average 19.6km and 6.5km south, respectively (p<0.05). Although northerly and southerly species did not differ significantly in occupancy changes, we found that for southerly species, the change in occupancy was positively associated with the proximity of a species’ distributional range boundary to our study area (p<0.05). This suggests that species along the northern periphery of their range gained more blocks than species for which Ohio is more central in their distribution. Poleward shifts in avian distributions may be more difficult to detect in our study because additional factors such as land cover change may affect distributions more strongly on this finer scale or within Ohio‘s largely human-utilized landscape. Our future analyses will attempt to partition variance in both climate and land cover change to elucidate environmental determinants of the changes we observed in Ohio‘s breeding bird distributions.

A copy of Kate’s poster can be viewed HERE.

Congratulations to the following students who received presentation awards at the 2011 AFO/COS/WOS meeting in Kearney, Nebraska.

Best Oral Presentation
CARA JOOS , Ph.D. Candidate, Division of Biological Sciences, University of Missouri, Columbia, MO (Advisor: Dr. John Faaborg), “Settlement order and productivity of Bell’s Vireo (Vireo bellii bellii).”

Cara JoosAssessing habitat quality is important in population studies because habitat quality influences the fitness of its occupants. We need a better understanding of the factors that influence fitness in order to make informed habitat management decisions. The ideal despotic distribution model hypothesizes that individuals select high quality territories first. This selection pattern should result in increased fitness of earlier arriving individuals, therefore territory settlement order will predict fitness of occupants. Cara and her co-authors estimated fitness as “productivity,” measured as total number of chicks fledged per territory and then tested if territory settlement date, the date the first egg was laid, whether males were philopatric or not, or Brown-headed Cowbird (Molothrus ater) abundance predicted productivity in a population of individually marked Bell’s Vireos (Vireo bellii bellii) in central Missouri. Prior to the arrival of vireos on their breeding grounds, Cara systematically searched territories for newly arriving males and noted the band combinations of returning occupants and color-banding as many new territory owners as possible. Next, she located and monitored nests to record the date that first eggs were laid and the number of chicks fledged. She also conducted point counts to estimate cowbird abundance. Cara found that both early arrival and nest initiation to be important predictors of productivity. Productivity declined with settlement date and first egg date but settlement date may be the more important of the two. For example, if two territories have the same first egg date, the one that was settled earlier will have higher productivity. Cara’s findings support the ideal despotic distribution model in which settlement order predicts fitness. Thus, if territory quality is a function of habitat features Cara’s results will allow us to better define high quality Bell’s Vireo habitat and allow land managers to make informed management decisions.

Best Poster Presentation
J. RYAN SHIPLEY, Oklahoma Biological Survey, University of Oklahoma, Norman, OK (Advisor: Dr. Jeff Kelly), “Why is there a gap in the breeding range of the Painted Bunting?”

Ryan Shipley

Explaining the factors that influence a bird species’ breeding range is an enduring problem in ornithology. Ryan’s research focused on trying to explain the breeding range of the Painted Bunting (Passerina ciris) a small Neotropical migrant songbird that occurs in two disjunct breeding populations in the United States. The larger population occurs primarily in the states of Texas, Oklahoma, and Arkansas whereas a smaller population exists along the Atlantic coast in North Carolina, South Carolina, and Georgia. Although landscapes vary greatly between these two regions, no obvious climatological or geographic features exclude Painted Buntings from occupying the gap between them. To investigate explanations for the disjunction of these breeding populations, Ryan and his co-authors at the Oklahoma Biological Survey used species distribution modeling to determine if the bioclimatic envelope derived from breeding location data would occupy the region where the species is currently absent. In addition, they used winter presence data to delineate regions with suitable conditions on the breeding ground during spring arrival and examined historical origins of this gap in the breeding range by modeling current distribution variables onto two Last Glacial Maximum (ca. 21,000 years ago) paleoclimate models. The results suggest that (a) a bioclimatic explanation does not explain the gap between the current breeding distributions and (b) the species exhibits niche tracking within these breeding regions. In addition, the paleoclimate distribution reconstructions suggest that the species’ migratory distance was historically shorter than it is at present, and that two, or possibly three populations may have previously existed in western Mexico, the Yucatan Peninsula, and southern Florida. These different glacial refugia may help explain the differences in molting schedules and migratory behavior seen in the two present breeding populations.

Congratulations to the following students who received presentation awards at the 2010 AFO meeting in Ogden, Utah.

Best Oral Presentations (2 awards)
JASON M. TOWNSEND, Ph.D. Candidate, State University of New York College of Environmental Science and Forestry (Advisor: Dr. James Gibbs), “Catharus thrushes as bioindicators of mercury hotpots: from the Catskills to the Caribbean.”

Jason Townsend

Jason’s research documented mercury bioaccumulation in a densely forested watershed of the Catskill Mountains, NY. Mercury is a potent neurotoxin that accumulates in the environment as a result of global atmospheric pollution. While many studies have documented mercury accumulation in aquatic ecosystems, little is known about mercury cycling in strictly terrestrial ecosystems. Jason’s study showed that mercury accumulation in the soil and leaf litter increased with elevation in this watershed. Thrushes of the genus Catharus, which are arrayed along this elevational gradient, also showed increased blood mercury content with increasing elevation. High elevation Bicknell’s Thrushes (C. bicknelli) and Swainson’s Thrushes (C. ustulatus) showed significantly greater blood mercury levels than did lower elevation congeners, Hermit Thrush (C. guttatus) and Veery (C. fuscescens). This finding could have particularly important health and conservation implications for Bicknell’s Thrush, which is generally restricted to forests above 1000 m in the northeastern United States. Furthermore, blood mercury levels in all species declined with season, indicating that early-season thrushes either carry mercury from their winter grounds or consume a diet higher in mercury during the early part of the breeding season (May–June 15). An additional analysis of mercury in Bicknell’s Thrushes wintering on Hispaniola showed the highest blood mercury levels of any birds in this study and also wide, site-specific variance, potentially reflecting local pollution patterns.

LINDA LAIT, M.S. Candidate, University of Lethbridge (Advisor: Dr. Theresa Burg), “The population structure and postglacial expansion of the Boreal Chickadee (Poecile hudsonicus).”

Linda LaitExplaining the geographic distribution of birds is an enduring pursuit in ornithology. Linda’s research examines the geographic distribution of Boreal Chickadees across northern North America. During the last glacial period, much of North America was covered by large ice sheets. Throughout this time, both fauna and flora survived in ice-free regions known as refugia. Two large refugia were known to have existed in North America—one south of the ice sheets, and one in Beringia (western Alaska). A number of smaller, disputed refugia may have also been present on both the east and west coasts of Canada. Many studies have looked at how mountain ranges and large bodies of water can act as barriers to gene flow. Obstacles such as these may have impacted the recolonization following the melting of the ice sheets, and may still play a role in limiting dispersal. The Boreal Chickadee (Poecile hudsonicus) is a small songbird that resides in the boreal forests of Canada and the northern United States. Linda used mitochondrial DNA from both field and museum samples covering all of the chickadee’s range to study the postglacial expansion of this species, and how physical barriers may affect the population structure. The mitochondrial DNA showed a general east/west split in the populations; the British Columbia/ Alberta/Alaska populations forming a ‘western haplogroup’ while the Newfoundland/Nova Scotia/ New Brunswick/Quebec populations form an ‘eastern haplogroup’. The Rocky Mountains do not appear to have acted as a barrier to dispersal in this species. Interestingly, both Alaska and Newfoundland were found to be distinct from all other populations. Microsatellite data supports Newfoundland as a distinct population, with little variation seen within the mainland populations.

Best Poster Presentation
CHRISTOPHER J. W. MCCLURE, Ph.D. Candidate, Auburn University (Advisor: Dr. Geoffery E. Hill), “Interpreting Breeding Bird Survey data in the face of climate change.”

Christopher McClureMost bird monitoring programs rest on an assumption that bird species are not becoming harder (or easier) to detect as years go by. One can imagine that if a species is growing progressively quieter each time a survey is conducted, fewer individuals will be detected with each survey. This trend in fewer individuals being detected could then be misinterpreted as a population decline. Such a systematic change in bird detectability – the probability of detecting a bird, given that it is present – seemed unlikely until recently. Studies have shown that many bird species are breeding and migrating earlier, presumably due to climate change. Because bird song rate is tied to breeding stage, a progressively earlier breeding date could potentially shift the timing of peak song rate, thus causing birds to be progressively harder (or easier) to detect during survey dates each year. To address this issue, Chris and his co-authors first had to determine how bird detectability changes within a single breeding season. They used audio recordings within their study site in Tuskegee National Forest, AL to examine seasonal changes in the detectabilities of 31 species during the breeding season of 2008. Next, they calculated the effect of a one-week shift in breeding activity by shifting the timing of peak detectability one week later and determining the effect of that shift on the detectability of each species during the month of June and then tested whether changes in detectability were correlated with population trends reported using Breeding Bird Survey data within the state of Alabama. Chris’s results indicated that migrant species show greater variation in detectability than year-round residents within a breeding season. Therefore a shift in breeding date should cause migrant detectability to decline more sharply during fixed survey dates than resident detectability. However, their assumed annual changes in detectability were not correlated with the population trends reported by Breeding Bird Survey data within the state of Alabama. Chris and his co-authors concluded that the Breeding Bird Survey is a useful index of bird populations.

Best Undergraduate Poster Presentation
LUIS E. VARGAS, Universidad de Costa Rica (Advisor: Dr. Gerardo Ávalos), “Forest structure and territory size relationship in the neotropical understory insectivore White-breasted Wood-wren”

Luis VargasOrnithologists have long been interested in the factors that affect territory size in birds. The Neotropical terrestrial insectivore Henicorhina leucosticta (Troglodytidae) maintains long-term territories through vocalizations and forages among leaf litter trapped in the understory vegetation and ground litter. As part of a Research Experience for Undergraduates project, Luis, a 2008 graduate of the Universidad de Costa Rica, studied the relationship between forest structure and H. leucosticta territory size in La Selva Biological Station, Costa Rica, during the non-breeding season in 2009. Forest structure was measured by assessing canopy openness and leaf area index (LAI) using hemispherical photography. Territory size was estimated with playbacks using local conspecific vocalizations. Luis and his co-authors found that territory size decreased as median LAI within a territory increased. Since LAI indicates the foliage area over the respective area of ground, territories with higher LAI are more likely to have greater leaf fall and leaf litter accumulation over the understory plants. The leaves trapped over the understory plants, the ‘areal leaf litter’, provide an important reservoir of arthropods available to understory insectivorous birds. Moreover, H. leucosticta frequently searches for nest materials within the areal leaf litter. Therefore, the long-term capacity of a given territory to supply enough arthropod prey and nest material is of great importance and likely to affect territory size, with larger territories found where there is relatively lower LAI, and consequently lower supply of food and nest materials. Within the context of the ‘structural cues hypothesis’, which proposes that birds adjust territory size using habitat structure as a predictor of prey abundance within a given site, Luis suggests that greater LAI in tropical rainforests can be used to infer higher arthropod abundance or more potential prey microhabitats for H. leucosticta, as well as other insectivorous birds with similar foraging behavior. Luis is currently in the process of applying to graduate school where he intends to study animal communication.

Congratulations to the following students who received presentation awards from AFO at the joint meeting of the AFO and the Wilson Ornithological Society in Pittsburgh, Pennsylvania.

Best Oral Presentations (3 awards)
ALEJANDRO RICO-GUEVERA, Ph.D. Candidate, University of Connecticut (Advisor: Dr. Margaret Rubega), “Evolutionary insights about the bill structure of nectivores”

Alejandro Rico-GueveraAlejandro’s research is focused on the evolutionary ecology of nectar-feeding birds. He is especially interested in both the morphological and ecological adaptations of nectivores and integrates the morphological study of museum specimens with performance experiments to test the functional significance of various traits. The research project he presented at the AFO meeting was aimed at examining the link between feeding mechanisms and social systems of nectivores. Studying arthropod foraging in hummingbirds with Gary Stiles, he decided to closely study hummingbird bills and found a puzzling set of hidden bill traits and hypothesized how those traits could be involved in feeding performance and social organization. Encouraged by his advisor, Margaret Rubega, Alejandro expanded his survey to all specialized nectivorous birds and found evolutionary convergences not previously reported. Features that improved feeding efficiency included structures finely tuned by physical laws in the nectar extraction process (e.g., forward projecting serrations, flexible tomia, and internal projections). Other traits, related to social systems, are sexually dimorphic backward serrations, bill tip daggers and hooks that Alejandro hypothesized were used as weapons by males during fights for resources. In short, nectivory in birds seems to favor the evolution of novel traits by coupling bill and tongue morphology to affect high nectar extraction efficiency, while dominance interactions over resources seems to favor the evolution of weapons in males.

JASON HILL, Ph.D. candidate, Pennsylvania State University (Advisor: Dr. Duane Diefenbach), “Post-fledging movement, behavior, and habitat use of adult Saltmarsh Sharp-tailed Sparrows”

Jason HillThe behavior of birds during the post-fledging period is largely mysterious. Jason studied the postfledging movement and habitat use of adult female Saltmarsh Sharptailed Sparrows (Ammodramus caudacutus) in Connecticut. This globally red-listed species occurs only in salt marshes along the Atlantic coast of the U.S., and is highly unusual in a number of regards. Both males and females are non-territorial and males provide absolutely no parental care—females do it all. Salt marshes are highly productive ecosystems, which allow females to raise 3-5 young per brood. Tidal flooding often accounts for greater than 50% of nest loss for this ground-nesting species. To study the behavior and habitat use of females, Jason radio-tracked female sparrows during the post-fledging period when they were providing care to fledglings that cannot fly for the first week or so. He also sampled vegetation where he daily flushed females and also in random locations within each female’s home range. Females, on average, used ~ 0.5 ha of space during this time. They used areas of the marsh quite unlike what they use for nesting habitat. Nests are generally placed in areas of relatively high ground towards the center of the marsh. Jason thinks that this strategy may minimize nest losses from flooding and nest predation by mammals such as raccoons and house cats patrolling the edge of the marsh. During the post-fledging period, however, females moved towards the edge of the marsh and were strongly associated with artificial ditches and natural channels. At low tide these water features generally empty out exposing mud that is likely to be a highly productive foraging area. In addition, these water features often have very tall vegetation (e.g., Spartina alterniflora) growing in them that may provide cover for the fledglings. Moving towards the edge of the marsh may also reduce drowning risks for fledglings before they are able to fly. These findings demonstrate the importance of using a broader view when describing and protecting a species’ “breeding” habitat. Female Saltmarsh Sharp-tailed Sparrows use a very different habitat during the nesting and post-fledging periods. Management and conservation strategies should recognize this broader view of “breeding” habitat to ensure the long-term survival of this species.

SARAH KINGSTON, Ph.D. candidate, University of Maryland and National Museum of Natural History (Advisor: Dr. William Fagan), “Genome–wide levels of introgression and divergence across Mexican Towhee hybrid zones”

Sarah KingstonSarah is interested in the evolutionary importance of introgression of genes across species boundaries and the interaction of hybridization with available habitat. To study this problem, Sarah’s research focuses on hybrid zones between two towhee species, the Spotted Towhee (Pipilo maculatus) and Collared Towhee (Pipilo ocai), in montane habitat in Mexico. These two species hybridize in two main areas: the Teziutlán and Transvolcanic gradients. The towhee system is a unique and interesting one to address questions about the evolutionary importance of introgression. A unique characteristic of the towhees in Mexico is an intersection of the two different hybrid areas and an area just south of the peak of hybridization, where each parental species exists in sympatry, but shows little evidence of interbreeding. This special area of sympatry offers an opportunity to contrast the habitats associated with hybridization and lack of hybridization. Much of the morphological variation across the hybrid gradients has been quantified, but a broad genome survey has not been completed. Sarah used a genomic approach to assess the prevalence of introgression in these towhee hybrid zones. Multi-locus analyses revealed not only a genetic differentiation between parental types, but also the divergence of populations within the areas of hybridization. Sarah also found evidence of bi-directional introgression across the species boundary which indicates that this boundary is porous to a portion of the genome. Finally, Sarah’s research with towhees suggests that the exchange of genes between species may be an important factor along the evolutionary trajectory of species.

Best Poster Presentation
KRISTEN M. LEAR, Undergraduate, Ohio Wesleyan University (Advisor: Dr. Jed Burtt), “Netting Methods Influence Age Distribution in Samples of Cliff Swallows.”

Kristen LearThe way in which an organism is captured may affect the subset of the population sampled. When sampling birds such as Cliff Swallows (Petrochelidon pyrrhonota), mist netting is often the preferred method of capture. Because the birds must fly into the net, the sample population could be biased for traits associated with such flights. Kristen and her collaborators set out to determine whether their netting method influenced the subset of the population they captured. They set up mist nets at the opening of the culverts within which Cliff Swallows establish large nesting colonies. To determine if netting methods influenced the identity of birds captured they either allowed Cliff Swallows to voluntarily fly into nets as they exited the culverts or actively flushed them into nets. Flushing involved walking through a colony and driving the birds into the net. Flushing may eliminate the potentially skewed results given by voluntary capture. Data collected from 3 sites, using a summed sample size of 3,062 birds, found that flushed birds tended to be older than birds that made voluntary flights into the nets. Kristen’s results show that the method of netting can give a skewed perspective of a population’s age structure and that researchers who use mist nets should keep this in mind when asking questions about population dynamics.

Competition was stiff for the student presentation awards at the joint meeting of the AFO and the Wilson Ornithological Society in Mobile, Alabama in April 2008. Congratulations to the following students who stood out and received presentation awards from AFO.

Best Oral Presentations (3 awards)
MEGAN FITZPATRICK, Undergraduate, Albion College (Advisors: Douglas W. White and E. Dale Kennedy), “The Effects of Thermal Environment on Incubation Behavior in House Wrens (Troglodytes aedon)”

MIKAELA G. HOWIE, M.S. degree candidate, William and Mary College (Advisor: Dr. Dan Cristol), “The infiltration of aquatic mercury into a terrestrial ecosystem”
RYAN BURDGE, M.S. degree candidate, William and Mary College (Advisor: Dr. Dan Cristol), “Eastern Bluebirds on golf courses: nestling pesticide exposure and diet”
Best Poster Presentation:

ERIK JOHNSON, Ph.D. candidate, Louisiana State University (Advisor: Dr. Phil Stouffer), “Ectoparasites affect bird condition in neotropical forest fragments”;
2007: Outstanding student presentation awards were presented for the first time ever at the 2007 annual meeting of the AFO at the University of Maine in Orono. Students received a two-year memberships in the AFO. In addition, Wiley-Blackwell Publishing Co., W.H. Freeman Publishing Co., Sinauer Publishing Co., Oxford University Press and Princeton University Press all donated prizes (books) for students. The AFO is most grateful to these companies. Student presentation awards will now be a regular and prominent feature of annual AFO meetings.

Best Oral Presentations
SUSAN B. SMITH, University of Rhode Island, “Influence of diet and food availability on fuel use and storage in songbirds during autumn migration in Rhode Island”

ANDREA TOWNSEND, Cornell University, “A test of the genetic benefits hypothesis for extra-pair paternity in the American Crow”
Best Oral Presentations – Honorable Mention:

BRENT HORTON, University of Maine, “Corticosterone as a factor in parental behavior in male White-throated Sparrows”
JASON TOWNSEND, SUNY-ESF, Syracuse, “Bicknell’s Thrush overwinter ecology in the Dominican Republic”
Best Poster Presentation:

JULIA MACKENZIE, Anglia Ruskin University in Cambridge, UK, “Impact of non-native flora on breeding success of Blue and Great Tits”