An inextricable link exists between dams and human development in the Pacific Northwest, but they can fragment rivers and reduce genetic connectivity for freshwater and anadromous fishes. Since the early-twentieth century, a series of hydropower and irrigation dams on the mainstem Klamath River, California, has fragmented migratory corridors and eliminated...
The combined effects of habitat loss, degradation, and fragmentation pose a serious threat to Earth's biodiversity, imperiling even relatively common species. 'Habitat' is necessarily a species-specific concept, and investigations of bird diversity relationships and subsequent efforts to prioritize conservation areas, are challenged by the difficulty of estimating complex habitat gradients...
The California Current Ecosystem (CCE) is a dynamic marine ecosystem from which many socioeconomically important fisheries species are harvested. In this thesis, a genotyping-by-sequencing (GBS) approach was used to examine genomic variation in an early life stage of the Dungeness crab (Cancer magister), which constitutes the most valuable single-species commercial...
The concept of the fundamental niche is frequently used in ecology to define the set of environmental conditions needed by a species to survive and reproduce (Hutchinson 1957). In contrast, the realized niche constitutes the locations where a species actually occurred, which is a function of both the environmental (abiotic)...
The distribution of mobile marine predators often reflects underlying dynamic ecological processes. The geographical focus of this PhD is the South Taranaki Bight (STB) of New Zealand, where wind-driven coastal upwelling generates productivity and prey to support a blue whale foraging ground. The STB is also New Zealand’s most industrial...
Foliar fungi – pathogens, endophytes, epiphytes – form taxonomically diverse communities that affect plant health and productivity. The composition of foliar fungal communities is variable at spatial scales both small (e.g., individual plants) and large (e.g., continents). However, few studies have focused on how environmental factors and host plant traits...
Understanding connectivity among exploited populations is critical to their sustainable management and long-term viability. In the marine environment, estimates of connectivity often rely on the use of genetic markers, as dispersal primarily occurs during a planktonic larval phase which is difficult to track using direct methods. In this thesis, we...
Reintroduction programs are increasingly being used to save animals from extinction and aid in their recovery. The California Condor (Gymnogyps californianus), one of the most endangered birds in the world, is a remarkable example of how reintroduction programs can help rapidly increase a species' population numbers and range following a...
Biological invasions pose one of the greatest threats to global biodiversity, but many naturalized invaders coexist with the native community. Community ecology theory provides a framework for understanding the mechanisms by which invaders might coexist with native species or exclude them from the community, thus informing management practices to maximize...
Herbs have been used for many centuries in diverse civilizations for the treatment of heart disease. Only a few natural supplements claim to have direct cardiovascular actions including hawthorn (Crataegus spp.) and berberine derived from the Berberidaceae family. Several different studies indicate important cardiovascular effects of hawthorn and berberine. For...