| Summary: | University of Minnesota Ph.D. dissertation. December 2016. Major: Conservation Biology. Advisor: Francesca Cuthbert. 1 computer file (PDF); xi, 117 pages. Waterbird populations have declined around the world as a result of anthropogenic impacts from habitat loss and degradation, direct mortality, reproductive failure, and disturbance from humans and non-native and domestic animals. Specialist species are particularly at risk from changing environmental conditions and disturbances compared to generalist species. Plovers, lapwings, terns, and other waterbird species in the Order Charadriiformes nest on the ground, near water, and in exposed areas with little vegetative cover. As a result of their specialized breeding ecology and habitat requirements, nests of these species are therefore highly vulnerable to animal predation, flooding due to rainfall and hydrologic fluctuations, and disturbance from humans and domestic animals. Different social, economic, and political situations among world regions present distinct opportunities and challenges for implementing species conservation. In this study, I explore breeding ecology and conservation of threatened ground-nesting waterbirds in two different systems: 1) Piping Plovers Charadius melodus that breed on lakeshore beaches in the Great Lakes region of the United States, and 2) a community of six species, including River Tern Sterna aurantia, River Lapwing Vanellus duvaucelii, Great Thick-knee Esacus recurvirostris, Indian Thick-knee Burhinus indicus, Small Pratincole Glareola lactea, and Little Ringed Plover Charadrius dubius, that nest on river sand and gravel bars in the Mekong River basin in Cambodia. First, I examine factors affecting nest survival and renesting, and compare in situ and ex situ management scenarios to evaluate the potential efficacy of egg salvage as a means to augment the Great Lakes Piping Plover population. Second, I investigate factors affecting nest and chick survival of riverine birds in Cambodia, and evaluate the effectiveness of a direct payment nest protection program to improve reproductive success. Third, I examine factors affecting multi-scale habitat selection, and the consequences of habitat selection on reproductive success of riverine birds in Cambodia. This study provides valuable new information that will aid ongoing conservation efforts for threatened ground-nesting waterbirds such as the Piping Plover in North America and riverine birds in Southeast Asia. This work also has implications for conservation of threatened species more broadly.
|
|---|