We summarize the factors that shaped the biodiversity of Chicago and its hinterland and point out the conservation significance of these ecological systems, addressing why conservation of Chicago’s biodiversity has importance locally and beyond. We highlight Chicago Wilderness (CW), a regional biodiversity conservation alliance committed to protecting nature and enriching the lives of the region’s residents. Chicago Wilderness, with over 250 institutional members, has for over a decade coordinated the efforts of diverse institutions, including federal, state, and local agencies, public land-management agencies, conservation organizations, and scientific and cultural institutions. Chicago Wilderness is committed to using science and emerging knowledge as a foundation for its conservation work. CW has several specialist teams that promote an interdisciplinary approach to conservation; we focus on the work of the CW Science Team, the one team with a research mission. The scientific investigations that are undertaken to provide a knowledge base for the work of Chicago Wilderness have drawn upon a wide variety of conservation paradigms, including that of resilience thinking, which we illustrate in a series of case studies.

From the time of its charter in 1832 the population of the City of Chicago grew explosively and the landscapes of the region were largely transformed both by the expanding physical footprint of the city and by the extensive development of agriculture in the hinterlands. This transformation was at the expense of highly biodiverse ecosystems that had been inhabited by populations of indigenous peoples who had themselves been agents in the historical development of the region’s biota. As a consequence of both public and private community planning early in the history of the city, the region retained substantial open space in the city itself and its hinterlands. In this chapter we describe the factors that determined the structure of the biota of Chicago and review recent large-scale attempts to manage the biodiversity of the region. We discuss recent biodiversity conservation strategies mainly through the lens of Chicago Wilderness, a regional biodiversity conservation alliance that emerged over a decade ago and that now has more than 260 institutional members. These members represent federal, state, and local agencies, public land-management agencies, conservation organizations, and scientific and cultural institutions. Despite the progress we show that the footprint of the city continues to grow and that there is significant work to be done even on questions of the basic natural history of the Chicago area.