Breeding Ecology Op Great Horned Owls and Barred Owls in Relation to Nesting Interior Least Terns at Salt Plains National Wildlife Refuge, Oklahoma: 1995 and 1996

Abstract

Thesis chapters were written in manuscript format suitable for submission to scientific journals or professional publications. Chapter I of this thesis follows the journal format of The Southwestern Naturalist and Chapter II follows the format of Journal of Field Ornithology. Chapter III is written according to guidelines in Condor and Chapter IV is written for submission to the Bulletin of the Oklahoma Ornithological Society. The goal of research efforts in 1995 and 1996 was to document avian predator impact on endangered interior least terns nesting at Salt Plains National Wildlife Refuge. Chapter I describes baseline habitats and pair densities of sympatric barred owls and great horned owls at salt Plains National Wildlife Refuge, and suggests barred owl habitat needs exclude them from being predators of least terns. Chapter II describes site-specific nesting success and microhabitat use for least terns throughout the alkaline flat. Chapters III and IV were methodologically similar to Chapter II, but on sympatric nesting species: snowy plovers and American avocets/black-necked stilts, respectively. Ring-billed gulls were newly documented avian predators on snowy plovers eggs and chicks, and two diurnal great horned owl sightings occurred on the alkaline flat in 1995 during the Charadriiform nesting season.