Population Biology Commons^™

Uncommon/Rare Avian Species Decline And Extirpation In Nested Assemblages Of Northeastern Illinois Wetlands, James M. Mcaley

All Capstone Projects

Baisa found that avian assemblages are highly nested in palustrine emergent wetlands in northeastern Illinois. He measured nestedness by constructing a binary matrix of species presence and absence across sites. Nestedness was also quantified using the Mann-Whitney U-test in his study.

The goal of this project was to sample the wetlands as Baisa had done in his study. By doing so, we will have 2 sampling events, approximately 10 years apart. Nestedness of the wetland communities will be checked, and data compared to that of Baisa. Emergent wetlands in northeastern Illinois were found by Baisa to contain highly nested avian …

Harpy Eagle (Harpia Harpyja) Conservation: Juvenile Behavior And Diet At A Nest Near Pijibasal, Darien, Hannah Rodgers

Independent Study Project (ISP) Collection

The Harpy Eagle (Harpia harpyja), the largest and most powerful bird of prey in the Americas, is declining throughout its range in Neotropical forests. Hunting and deforestation threaten populations in the most important remaining eagle habitat in Central America, the Darien province of Panama. These eagles may have the longest postfledging juvenile dependency of any raptor, though juvenile behavior during this period is poorly studied. This study monitored an 11-month-old juvenile for 7 days at a nest near the indigenous community of Pijibasal in order to study behavior and diet. Researchers recorded the juvenile’s location and behavior, studied prey remains …

Population And Morphological Changes In American Kestrels Through Space And Time, Teresa E. Ely

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

A once common raptor, the American kestrel (Falco sparverius) has experienced population declines in the last two decades throughout North America. Many hypotheses exist about the decline, including mortality from West Nile virus, rodenticide poisoning, climate change, an increase in predators, and core habitat loss or degradation, which could influence food availability. Food availability is key to raptor survival and reproduction, and changes in food availability throughout the year can have lifelong effects on size and body condition. Here we examine how morphology, specifically mass and wing chord, has changed at seven migration sites throughout North America as …

Avifaunal Community Composition In A Tropical Forest Corridor: A Case Study From The Atherton Tableland, North Queensland, Don Jones

Independent Study Project (ISP) Collection

Bird communities in tropical forest ecosystems are highly threatened by habitat loss and fragmentation. Replanted corridors connecting isolated forest remnants are a popular method of ameliorating certain negative impacts of habitat fragmentation. Such linkages can theoretically facilitate greater dispersal, increase gene flow, and reduce the risk of local extinctions in forest birds. However, relatively few studies have examined the utilization of reforested corridors by birds, and little hard data exists to support claims that this type of resource and time intensive project is the best use of often scarce funding for conservation. This study examined the avifaunal community present in …

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 …

Swans: Their Biology And Natural History, Paul A. Johnsgard

Zea E-Books Collection

The seven species of swans of the world are an easily and universally recognized group of waterfowl, which have historically played important roles in the folklore, myths and legends in many of the world’s cultures. Among the largest of all flying birds, they have also almost universally been used as symbols of royalty, grace and beauty, and largely for these reasons swans have only rarely been considered acceptable as targets for sport hunting. Swans occur on all the continents except Africa, although most species are associated with the temperate and arctic zones of North America and Eurasia. Among birds, swans …

Impacts Of Man-Made Structures On Avian Community Metrics In 4 State Parks In Northwestern Arkansas, R. D. Keith, B. Grooms, R. E. Urbanek

Journal of the Arkansas Academy of Science

Avian community metrics often differ between areas with no human disturbance and areas with high levels of human disturbance. However, the relationships between avian community metrics and smaller-scale disturbances are not as clear. Our goal was to investigate if avian abundance, richness, evenness, and diversity differed in areas with and without small-scale human developments. We used fixed-radius 50-m avian point counts to compare points which contained a man-made structure (n = 47), such as a picnic area, road, or campsite to those that did not contain a man-made structure (n = 181) at 4 state parks in Arkansas during 18 …