Doctoral Dissertation Research: Spatial and Temporal Configurations of Potential Distributions of Grassland Sparrows

博士论文研究：草原麻雀潜在分布的时空配置

• 批准号: 1131644
• 负责人: Townsend Peterson
• 金额: $ 1.17万
• 依托单位: University of Kansas Center for Research Inc
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-15 至 2013-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1131644&HistoricalAwards=false
• 关键词: Doctoral; Dissertation; Research; Spatial; Temporal

One problem that has vexed biogeographers and others interested in the distribution of different species is the difficulties that many species have in adapting when their habitats are changed by human activity or other forces. A related problem is the difficulty in monitoring the number and distribution of these species. One such species is Henslow's sparrow (Ammodramus henslowii), a grassland-nesting bird that is found in the central U.S. and nearby parts of Canada. This doctoral dissertation research project will take a multifaceted view of Henslow's sparrow distributional biology, focusing on improving understanding about how populations respond to broad-scale habitat changes and of the extent to which human activities affect the amount and distribution of its breeding habitat, particularly in Midwestern grasslands. Henslow's sparrows currently have a distribution that is patchy and local; although the limits of the species' range are perhaps well-known, existing surveys are largely confined to roads. Current information therefore may neither represent all available habitat, such as grasslands in airfields, military bases, and reclaimed surface mines, nor does it accurately estimate population trends. No detailed map of suitable habitat for the full breeding distribution currently is available. The doctoral student will use ecological niche models to produce a detailed distributional understanding by identifying key environmental variables and characterizing the amount of suitable breeding habitat and its spatiotemporal dynamics within a patch-matrix framework while taking into account landscape heterogeneity and habitat patch characteristics produced by year-to-year disturbance dynamics. Once these models have been validated through independent field surveys, year-to-year variation of the extent and arrangement of suitable patches will be analyzed. This analysis will provide insight and explanation for the broad-scale nomadic behavior documented in earlier studies of the breed. These models also will be used to evaluate how well current survey techniques function to sample Henslow's sparrow breeding habitat. The student will evaluate these models by summarizing the amount of suitable grasslands in patches immediately surrounding routes identified by the North American Breeding Bird Survey and by comparing it to the broader distribution of this habitat (produced by the niche models) and the proportion of habitat types within the landscape matrix (using land-cover maps).Henslow's sparrows have very specific nesting habitat requirements that make them relatively good indicators of healthy tallgrass prairie ecosystems. Like many other obligate grassland species, they have suffered severe habitat loss as a result of fragmentation and conversion of grasslands, a loss estimated to have exceeded 99 percent across North America. Unlike a few other species that adapted easily to these changes, Henslow's sparrows have not responded well across their breeding range, and they have exhibited significant population declines over the last century. Recent studies have shown that this species does not return consistently to patches of habitat from year to year, which makes management of their habitat more difficult. This project will make significant contributions to the assessment of Henslow's sparrow populations and trends. The project also will provide a test of the capability of current survey techniques to effectively survey rare species and spatially limited habitat types. The project also will facilitate evaluation of recommendations for habitat management that more effectively accommodate the nomadic behavior as well as the amount, distribution, arrangement, or disturbance dynamics of this habitat at landscape scales. The results of this project therefore will potentially affect how species like Henslow's sparrows are managed and will prompt reevaluation of population trend estimates or habitat availability for other, similar species. As a Doctoral Dissertation Research Improvement award, this award also will provide support to enable a promising student to establish a strong independent research career.

一个让生物地理学家和其他对不同物种分布感兴趣的问题是许多物种在人类活动或其他力量改变栖息地时遇到的困难。 一个相关的问题是监测这些物种的数量和分布的困难。 其中一种是Henslow的麻雀（Ammodramus Henslowii），这是一种在美国中部和加拿大附近发现的草地巢穴鸟。 该博士学位论文研究项目将对Henslow的麻雀分布生物学进行多方面的看法，重点是提高人们对种群如何对广泛栖息地的反应以及人类活动影响其繁殖栖息地的数量和分布的程度，尤其是在中西部草原的程度。 Henslow的麻雀目前的发行版本是斑点且本地的。尽管该物种范围的极限可能是众所周知的，但现有的调查主要局限于道路。因此，当前的信息不能代表所有可用的栖息地，例如机场，军事基地和回收地面地雷的草原，也不能准确估计人口趋势。 目前尚无适用栖息地的详细地图。 博士生将使用生态利基模型来通过识别关键的环境变量并表征合适的繁殖栖息地及其在贴片垫框架内的时空动态的数量来产生详细的分布理解，同时考虑了景观异质性和逐年生产的栖息地特征。 一旦通过独立的现场调查验证了这些模型，将分析合适贴片的程度和排列的年度变化。 该分析将为该品种早期研究中记录的广泛游牧行为提供见识和解释。 这些模型还将用于评估当前的调查技术在采样Henslow的麻雀育种栖息地的功能。 学生将通过汇总北美繁殖鸟调查确定的路线中的合适草原的数量来评估这些模型，并将其与该栖息地的更广泛的分布（由Niche模型产生）以及在景观中的栖息地中的栖息地类型的比例更广泛（使用陆地封口图）。生态系统。 像许多其他义务草地一样，由于草原的破碎和conversion依，它们遭受了严重的栖息地损失，估计北美的损失估计超过99％。 与其他一些容易适应这些变化的物种不同，Henslow的麻雀在其繁殖范围内的反应不佳，并且在上个世纪，它们的人口大幅下降。 最近的研究表明，该物种每年都不会始终如一地返回到栖息地的斑块，这使得对其栖息地的管理更加困难。 该项目将为评估Henslow的麻雀种群和趋势做出重大贡献。 该项目还将对当前调查技术有效调查稀有物种和空间有限的栖息地类型的能力进行测试。 该项目还将促进对栖息地管理的建议评估，以更有效地适应该栖息地的游牧行为以及该栖息地的数量，分布，布置或干扰动态。 因此，该项目的结果可能会影响亨斯洛（Henslow）的麻雀（Henslow）麻雀（Henslow's Sparrows）的管理方式，并会促使对其他类似物种的人口趋势估计或栖息地的可用性进行重新评估。 作为博士学位论文研究改进奖，该奖项还将提供支持，使有前途的学生能够建立强大的独立研究职业。