RUI/Collaborative Research: MSB-ECA: Mice-o-scapes: Using isotopes to understand the effect of climate and landscape change on small mammal ecology over the past 100 years

Climate, vegetation, and land-use change have had a dramatic impact on environments and species ecology across the United States over the past 100 years. Understanding these impacts is necessary for guiding future conservation and management decisions, and for developing indicators to assess ecosystem health. While much work has focused on the response of ecosystems to these changes on local or regional scales, many questions remain as to how climate and landscape changes will affect ecosystems at a continental scale. Small mammals, such as rodents, represent a significant proportion of the mammalian species in North America, and are bellweathers of ecosystem change. Small mammals record many aspects of their diet and environment in their tissues via stable isotopes, but key questions remain about the spatial scale represented by small-mammal isotopes and the aspects of the environment that they record.

This work will fill a major gap in our understanding of the climatic and environmental controls on stable isotopes recorded by small mammals at a continental scale. Specifically, we will combine biogeochemistry and modeling techniques using modern specimens obtained from the National Ecological Observatory Network (NEON) combined with historical specimens from natural history museums. We will determine how the isotopic composition of small mammals varies in relation to continental-scale climate and vegetation gradients and create mice-o-scapes?isotope landscape models predicting the stable isotopic composition of small-mammal hair across the United States. These landscape models will allow us to better understand the spatial scales and environmental variables recorded by small mammals, as well as differences in diet among species. We will then use historical small-mammal specimens obtained from various museum collections to assess how small mammals have responded to environmental change from the late 19th century to the present. We will target four different regions of the United States that have undergone dramatic but different forms of land-use change over the past 100 years, including urbanization, agricultural expansion, deforestation, and grassland-rangeland transition. This project emphasizes the importance of integrating museum collections as archives of ecological change with the NEON network, while helping to establish the careers of the young female research team and increasing research opportunities for underrepresented minorities at a Hispanic-serving institution.