Distribution, Abundance, and Habitat Associations of the Long-Billed Curlew in Southwestern North Dakota
Date of Award
Master of Science (MS)
Gathering information on North American bird populations calls for long-term monitoring programs covering extensive geographic region to provide basic information on distribution, habitat use and availability, abundance, and changes in abundance. Information regarding population size, distributions and trends is of critical importance to conservation planners, managers, and biologists concerned with widespread degradation of ecosystems, alteration and loss of habitats, and understanding the effective conservation of a species. In accordance with the recommended monitoring of bird populations, especially species of high conservation concern, I undertook a study of the long-billed curlew (Numenius americanus parvus; hereafter LBCU or curlew). The LBCU were once abundant over most of the shortgrass and mixed-grass prairie in the United States and Canada. In the mid- to late 19th century, LBCU numbers drastically declined due to the double combination of over-hunting prior to the Migratory Birds Convention Act, and extensive habitat loss from conversion of native prairie to monocrop agriculture.
The current lack of scientific knowledge regarding LBCU population sizes and distributions make it difficult to evaluate the current status of the population. This study looked at estimating abundance by conducting census route jrveys throughout the 2005 and 2006 field seasons. Habitat use was analyzed as identified breeding LBCU locations were complied with land cover data. This will provide wildlife managers information as to what the LBCU prefers for breeding habitat and to where they can help promote the safeguarding of this animal.
A conservative abundance estimate of 518 and 2,074 breeding LBCUs were found in 2005 and 2006, respectively. It was found that LBCUs prefer short-growth grr slands and areas with large amounts of wetland area. They tend to avoid extensively cultivated areas and areas of developed property.
The breeding biology, abundance estimate and relative importance of various habitats to LBCUs in North Dakota is provided here. Wildlife managers must evaluate these results and consider the possibility of labor-intensive efforts.
Ackerman, Daniel S., "Distribution, Abundance, and Habitat Associations of the Long-Billed Curlew in Southwestern North Dakota" (2007). Theses and Dissertations. 3022.