Integrating Soil Property Surveys and Soil Landscape Models in the Development of a Habitat Suitability Model for Dakota Skipper, a Threatened Butterfly Species

根据联邦濒危物种法案，达科他Skipper （Hesperia dacotae）是一种受威胁的蝴蝶物种。其分布局限于混交草草原生境，其分布范围已急剧减少。随着萨斯喀彻温省南部和曼尼托巴省混合草原栖息地的持续减少，达科他Skipper的丰度也被认为在下降，但在这一点上，关于栖息地的适宜性和可用性存在知识差距。根据之前在马尼托巴省和美国北部的调查，达科他Skipper栖息地的适宜性不仅仅是由可用的原生草原植被的存在与否控制的：似乎与其他环境变量有相互作用，包括选择土壤性质和达科他Skipper栖息地之间的一些相关证据。不幸的是，这些先前的研究并没有恰当地描述土壤、植被和达科他Skipper种群之间的关系。因此，本研究的具体目标是通过：a)评估达科他Skipper的存在与残余混合草地斑块中选择土壤性质之间的相关强度，b)预测土壤性质的分布，建立达科他Skipper栖息地的预测土壤景观模型。然后，这些信息可以与其他环境变量的调查相结合，以建立达科他跳鹬的栖息地适宜性模型，并建立一个建模框架，以基于类似的模型参数为处于危险中的无脊椎物种开发其他栖息地适宜性模型。

The Dakota Skipper (Hesperia dacotae) is a threatened butterfly species under the federal Species at Risk Act. Its distribution is limited to habitats of mixed-grass prairie, which has decreased dramatically in extent. As mixed-grass prairie habitat continues to decline across southern Saskatchewan and Manitoba, the abundance of Dakota Skipper is also presumed to be declining, but at this point, there is a knowledge gap pertaining to habitat suitability and availability. Based on previous surveys in Manitoba and the northern US, Dakota Skipper habitat suitability is controlled by more than just the presence/absence of available native prairie vegetation: there seems to be an interaction with other environmental variables, including some evidence of correlation between select soil properties and Dakota Skipper habitat. Unfortunately, these previous studies were not designed to properly characterize the relationship among soils, vegetation, and Dakota Skipper populations. Therefore, the specific objective for this proposal is to develop a predictive soil-landscape model for Dakota Skipper habitat by: a) evaluating the correlation strength between Dakota Skipper presence and select soil properties within remnant mixed-grass prairie patches and b) predicting the distribution of those soil properties. This information can then be integrated with surveys of other environmental variables to develop a habitat suitability model for Dakota Skippers and a modeling framework to developing additional habitat suitability models based on similar model parameters for invertebrate species at risk.