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Full-Text Articles in Population Biology
Marine-Derived Nutrient Cycling In The St. Croix River, Maine, Betsy Barber
Marine-Derived Nutrient Cycling In The St. Croix River, Maine, Betsy Barber
Electronic Theses and Dissertations
Anadromous species can boost freshwater productivity through nutrient subsidies. Along the Maine coast of the northeast United States, several alewife populations are recovering after freshwater connectivity is restored. Iteroparity in this part of their range may reduce their role as nutrient subsidies. Stable isotope analysis was used to detect marine-derived nutrient input. Spatial and temporal trends were characterized in the St. Croix as a baseline before alewife recovery, and nutrient-diffusing substrates indicated nutrient co-limitation. A reference watershed was used to compare nutrient dynamics when alewives were present versus absent. Results indicated isotope shifts within particular functional feeding groups, but not …
Survival, Harvest, And Drumming Ecology Of Ruffed Grouse In Central Maine, Usa, Samantha Davis
Survival, Harvest, And Drumming Ecology Of Ruffed Grouse In Central Maine, Usa, Samantha Davis
Electronic Theses and Dissertations
Understanding population dynamics and how species interact with their environment are important components for conservation and management. Ruffed grouse (Bonasa umbellus) are a widely distributed and common game bird in North America and are a considered an important economic and cultural icon in Maine. Although they are a well-studied species, there has been little research focused on ruffed grouse population dynamics and habitat relationships in Maine. My thesis aims to improve this knowledge gap by focusing on research related to survival and harvest of ruffed grouse, as well as male ruffed grouse resource selection at breeding display sites. Ruffed grouse …
Measuring Fertilization In Populations Of Sea Scallop (Placopecten Magellanicus): Developing And Testing Methods In The Laboratory And Field, Skylar Bayer
Electronic Theses and Dissertations
Most marine organisms are broadcast spawners, releasing their sperm and eggs into the water column. Methods of measuring in situ fertilization have proven successful with a few model species, which are reviewed in my introductory chapter. However, many commercially exploited species, such as the sea scallop Placopecten magellanicus, have been neglected. Sea scallop populations have greatly increased from fishing closures, but the mechanism behind this response is uncertain, particularly in regard to fertilization. In this dissertation I developed a methodology of measuring fertilization success and spawning events of P. magellanicus, tested it in laboratory and field settings, and …