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Tree Canopy Cover Influences Habitat Use Of Breeding Birds At Jack Mountain Wildlife Management Area, Kaleigh Thomas

Honors Theses

Across the United States, bird populations have declined due to habitat loss. To better understand habitat use by birds, researchers observed populations at Jack Mountain Wildlife Management Area in southwest Arkansas. Students at Ouachita Baptist University surveyed 94 point count locations to estimate species diversity (total number of species observed) and species abundance (total number of individuals observed). At each point, students recorded the percentage of tree canopy cover, ground cover, midstory cover, and shrub cover. These variables were used as explanatory variables in multiple regression analyses to determine which variables were influential in explaining variation in species diversity and …

Migration-Associated Variation In Blood Parasitism, Body Condition, And Stress In Gambel’S White-Crowned Sparrows (Zonotrichia Leucophrys Gambelii), Julianna Deibel

Scripps Senior Theses

Migration is a widespread behavior in animals which both causes and is motivated by fluctuations in nutrient availability. Migration is ecologically important, as it connects areas of differing primary productivities and carries pathogens over distance. The relationship between migration and disease is complex, sensitive to anthropogenic disturbance, and influenced by ecological cycles as well as host, vector and parasite life cycles. Four central migration-infection mechanisms have been proposed: migratory susceptibility, migratory exposure, migratory escape, and migratory culling. These mechanisms may yield increased or decreased infection post-migration, based on migration’s physiological tax and the concentration of pathogens along migratory pathways.

To …

Investigating Birds As Dispersal Vectors Of Litylenchus Crenatae Subsp. Mccannii (Anguinidae), The Nematode Associated With Beech Leaf Disease, Spencer Rock Parkinson

Graduate Theses, Dissertations, and Problem Reports

Beech leaf disease (BLD) is an emerging forest pathogen primarily affecting American beech (Fagus grandifolia, Ehrh.) in North America and has been attributed to tree mortality of sapling sized trees within five to seven years of infection. Symptoms typically occur in regenerating American beech thickets sprouting from roots of trees killed by beech bark disease. Scientists first observed BLD in Ohio in 2012 and currently has spread to 15 states in the USA and one Canadian province. The nematode Litylenchus crenatae subsp. mccannii (Lcm) is highly associated with BLD symptoms, interveinal chlorosis and defoliation of leaves, and is currently …