by Liam Heneghan
1. Introduction
Chicago is the largest city in the US Midwest, and the third largest in the country, with a metropolitan population of 2.7 million people . The greater Metropolitan Statistical Area (MSA) to which Chicago belongs has a population of 9,461,105. The density within the city is 20 519/km2, which is more than fifty times denser than the state of Illinois as a whole. The radical and rapid transformation of the landscape that has occurred over the past century and a half in order to accommodate this burgeoning population might suggest that Chicago is not an especially promising place to undertake a large scale conservation effort. However, the region supports conservation effects that are recognized as significant at the local, national and international scale. That significant biodiversity protection occurs in Chicago is a consequence of the region’s climate and its evolutionary and ecological history, as well as being deriving from decisions instituted by the human population, both before and after settlement of the region by European and other non-indigenous populations (hereafter referred to as “settlement”), that resulted in either setting land aside from development or maintained the characteristic biodiversity of the area.
In this chapter 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 effects directed at Chicago’s biodiversity has importance locally and beyond. Our main focus in the chapter is the work of Chicago Wilderness, a regional biodiversity alliance commitment to protecting nature and enriching the lives of the residents of the area. Chicago Wilderness has for over a decade served to coordinate the efforts of a diverse group of institutions included federal, state, and local agencies; public land management agencies, conservation organizations; and scientific and cultural institutions. We describe the history and structure of the alliance and describe the four key initiatives of Chicago Wilderness, namely, 1. Restore the health of local nature, 2. Green infrastructure, 3. Combating climate change, and 4. The Leave No Child Inside program. Although Chicago Wilderness has received much positive attention over the past decade and its work has been recognized by planners, academics, and editorialists, and by the agencies that make up the alliance, the efforts have not been without controversy. We give examples of the controversies and indicate how the alliance has learned from them.
Chicago Wilderness has a commitment to using science and emerging knowledge as a foundation for its conservation work and this is reflected in the role of a Science Team, one of four specialist teams, in the alliance . The scientific investigations that are undertaken to provide a knowledge base for the work of Chicago Wilderness has drawn upon a wide variety of conservation paradigms (see the summary of projects below). For the purposes of this chapter we are especially interested in illustrating the use of resilience thinking as a lens through which to assess the work of the coalition. In particular, we argue that a resilience framework is useful for evaluating the growth, development and persistence of the institutional collaboration of Chicago Wilderness. Additionally, we show that resilience can inform future thinking about ecosystem management in the region. Finally we frame Chicago Wilderness as a social-ecological system, one where the intra- and inter-institutional interactions shape regional biodiversity, which in turn affects the people living in the Chicagoland area. The work of Chicago Wilderness can simultaneously benefit from this resilience framework, but in turn, because of the extensive nature of conservation efforts in the region, a case study of the region can contribute to refining the use of resilience as a lens for viewing the management of resources in metropolitan settings.
2. Conceptually framing a region – Resilience, adaptive management, and institutional analysis and development (IAD)
Resilience has been defined in a variety of ways in the ecological literature to designate different aspects of the behavior of systems (Gunderson 2000). One use of the term, the one we adopt in this chapter, is the amount of disturbance that a system can absorb without changing state (Holling 1973). This may be called ecological resilience and is distinguished from engineering resilience which measures the time required for a system to re-equilibrate after a disturbance. Gunderson (2000) notes a key distinction between these different forms of resilience: ecological resilience makes different assumptions regarding the existence of multiple stable states (stability domains). From the perspective of this assumption regarding possible multiple stable states for a given system a disturbance may facilitate a shift from one system condition to another – there may be no simple return to equilibrium. Recognizing that relatively few ecological factors influence the state of the system, these key variable are hypothesized to change the stability domains at a relatively slow rate (Gunderson 2000).
The state of a ecological system can be understand as emerging from the self-organizing properties of that system. An especially influential heuristic device for examining self-organization is the adaptive cycles (Holling 1992). The adaptive cycle describes changes in a system in terms of two systems properties: stored capital, and connectivity and system organization (Holling 1986). The cycle can be considered in four phases, an exploitative, conservation, destructive and reorganization phase. Classic accounts of ecological succession are discussed in terms of the exploitative and conservation phases, the former representing the early phase of restoration, the latter referred to a the “climax” phase in the classical ecological literature. However, as ecological succession proceeds system resilience is diminished and climax vegetation becomes susceptible to disturbances – fires, pest outbreaks and the like – that tip the system into a “creatively destructive” phase of the adaptive cycle. As the system reorganizes it is, from this perspective of this model, most vulnerable to shifts to shifts to new stable states (Gunderson 2000). This is because there the regulatory feedbacks that may typically maintain the system are looser than they otherwise would be.
Resource crises, for example biological invasion, changes in waterways as a result of eutrophication, may signal a shift from one regime to another. A key insight emerging from the resilience literature is that the “command and control” approach to resource management results in loss of systems resilience. In contrast to disciplinary perspectives that aim to limit uncertainty and maximize a particular output from systems (productivity from agricultural systems, for example) resilience models promotes an integrative and holistic approach, terms “adaptive management”. Gunderson (2000) argues that such management is adaptive in as much as it acknowledges uncertainty in a managed system. This called for a level of flexibility in management responses that more conservative management may not find acceptable. Management implemented adaptively can result in these actions can be regarded as treatments in an experimental sense creating opportunities to test ideas and evaluate these actions (Underwood 1995).
In order to manage adaptively the institutions charged with overseeing a system may benefit from an appropriate orientation towards learning and governance. Such attitudes are investigated under the term “social learning”.
3. Shaped by ice and fire: factors influencing the biodiversity of the Chicago Wilderness region
The landforms of the Chicago region were largely shaped by glaciation events acting on layers of sedimentary rock laid down in shallow seas. The most recent of these glaciations, the Wisconsin-episode, melted approximately 16,000 years ago and the debris of this event can be found throughout the Chicago region, though deposits from older glaciations occur south of Chicago. This glaciation produced a variety of topographical features still visible on the present-day landscape, including a suite of terminal moraines. The more prominent terminal moraines influenced both the accumulation of water in the landscape as the glaciers receded and still manifest themselves as a series of uplands, important for the development of the vegetation. Lake Michigan along with the other Great Lakes also formed in response to glaciers which over a period of hundreds of millennia advanced and retreated along the waterways. Initially, Lake Chicago was deeper and more extensive stretching out many miles beyond the present shores of the present day Lake Michigan of which Lake Chicago it was the progenitor. The advance and retreat of the ice deposited gravel, sand, silt, and clay and rocky debris throughout the region which influenced drainage. The composition of soils in the region and their drainage has had significant impacts on the development of the region’s biodiversity.
In addition to the influence of the relatively recent glacial history on Chicago’s landforms, the climate, of course, has also influenced the successional development of the region’s biodiversity. The climate of the region is a continental one with winters characterized by the periodic incursion of cold Arctic air and the occurrence of at least two or three major storm systems resulting in significant accumulation of snow. The average temperatures in January are typically below 0oC. Because of the relative flatness of the terrain wind chills effects can be significant. Summers are dominated by warm humid air originating from the Gulf of Mexico with summer temperatures in averaging above 27oC. Temperatures in all seasons are also influenced by the proximity of Lake Michigan, second largest of the Great Lakes (by volume), which produces a so-called lake effect, resulting in cooler temperature nearer the lake in summer and warmer breezes during the cold season provided that the lake is not frozen. Precipitation totals 86 cm a year on average, most of it falling as rain in the summer months (Greenberg 2002).
The combination of the influences of glacial history on topography and the recently developed soils along with the influences of climate and fire working on the regional pool of species has influenced the biodiversity of the region. There has been considerable attention paid to the reconstruction of the post-glacial history of Illinois (King 1981, Baker et al. 1989, Nelson et al. 2006). The initial tundra-like post glacial vegetation was briefly replaced by one dominated by spruce (Picea) which in turn was increasingly colonized by deciduous trees as the temperatures increased. Temperatures and precipitation vacillated for several thousand of years and vegetation responded with conifers and deciduous trees alternatively dominating. A landscape configuration familiar to contemporary observers, characterized by a patchwork of woodlands, prairie and wetlands emerged about 8500 BP although these patterns remained highly dynamic and spatially distinctive. In the Chicago region (northern Illinois) xeric oak-hickory forest dominated. In the last several centuries climate and vegetation have remained dynamic with the regions experiencing cooling and xeric trends alternating with warming and more humid one. In the years before the large-scale clearing of vegetation associated with the establishment and growth of Chicago there was a warming trend increasing the prevalence of deciduous vegetation.
The role of fire in determining the configuration of habitats across the landscape of Northeast Illinois and in the maintenance of disturbance dependent habitat has been contested among academic ecologists over the course of the 20th Century. Even by the time ecologist Edgar Nelson Transeau wrote of wrote on the factors influencing the origins, development and maintenance of the Midwestern prairies in the 1930s (Transeau 1935) he can outlines several competing hypotheses already extensively debated in the literature, for instance, prairies as “scars” persisting after the ecological conditions producing them had terminated but maintained by human intervention; prairies as persisting because of unfavorable soil conditions (“immature soils”); prairies as the “pyrogenic victory of Indians and pre-Indians” who maintained the prairies as pasture and hunting ground. To this list one can add the role of large grazers, especially bison, in maintaining prairie vegetation (Anderson 2006). Contemporary opinion is that the mixture of prairie, savanna, and forest vegetation in the Chicago region, the so-called “vegetation mosaic”, is influenced by interaction of both climate and fire (Anderson 2006). Research on the use of fire as a means of maintaining this mosaic has been prevalent since the 1960s and the use of prescribed fire remains contentious in the region.
4. “City of big shoulders”: the growth of Chicago and the transformation of natural landscapes.
The suitability of lands on the south-east of Lake Michigan for the growth of an urban center is attributable to many of the same reasons that influence the ecological communities of the region. The lake and waterways of the region provided an abundant supply of freshwater; the youthful post-glacial soils are fertile, and there is an abundant supply of accessible resources including significant supplies of timber [and ore] to the north in Wisconsin. The early colonization of the region by European settlers was influenced by the region’s location close to a continental divide. Historically, the location of continental divide providing portage between the Great Lakes and the Mississippi River put Chicago at an important crossroads. Furthermore, Chicago is roughly located midway between pole and equator (coordinates 41°52′55″N 87°37′40″W) and its continental climates ensure a relatively long and productive growing seasons. This combination of geographical advantages was decisive in the location of the city. Despite its many ecological benefits, historian William Cronon (1992) points out though that the precise location of the young city had numerous shortcomings related to the marshiness of the ground close to the lake, which necessitated the raising of the city in its early years to escape the water logging of the streets which were frequently flooded.
After its founding in 1832 the population growth of the city of Chicago was unprecedented. By 1890 it had become the third US city to have a population of 1,000,000 (cite). In 1900 it was the second most populous city in the US; only New York City was larger. After 1900 the growth slowed but by this time there had been a major transformation of landscapes of the region. The exceptional favorableness of the Midwest, climatically and edaphically, for agriculture combined with the rapid growth of the human population in the region from the mid-nineteenth century resulted in rapid transformation not only of lands proximate to the metropolitan areas but of entire biomes. Of the estimated 8.9 million hectares of prairie “originally” in Illinois 930 hectares remain – a decline of 99.9% (Steinauer and Collins 1996). In the space of less a century much of the natural landscape of the region had been ceded to domestic and industrial use in the city and to agriculture in the hinterlands. Around the turn of the century there was recognition that some of the natural heritage of the region should be retained.
Though not as influential perhaps as market planners (“moneymaker” planning) community planners in Chicago, public and private, dedicated to making Chicago a “good” place to live, had a determinative influence on the retention of open space in the young city and its hinterlands (Abbott 2004). The Plan of Chicago in 1909 (the so-called Burnham Plan), though commissioned by the Chicago commercial elite is the most widely known culmination of such early efforts to ensure “that the city may be made an efficient instrument for providing all its people with the best possible conditions of living” (from the Plan of Chicago quoted in Smith (2006). A central proposal of the plan was the “improvement” of the lake front by the creation of a shoreline parkway and the development of Grant Park, a large 1.29 km city park which had been largely undeveloped. The plan also envisions an outer park system, and made provisions for a system of widened streets and avenues. The majority of the open space set aside by planning efforts such as this was maintained as parks, often with formal gardens rather than maintaining representations of pre-settlement habitat.
More consequential for the conservation of the presettlement vegetation was the creation of a systems forest preserves and conservation districts in the early years of the twentieth century. There are 62,240 ha of land in this system in the counties that include and surround Chicago (Packard 2004). The purpose of this system as annunciated in 1913 act that created them has a explicit conservation focus; the land was to be acquired “for the purposes of protecting and preserving the flora, fauna and scenic beauties” and furthermore “to restore, restock, protect and preserve the natural forest and said lands together with their flora and fauna, as nearly as may be, in their natural state and condition, for the purposes of the education, pleasure, and recreation of the public.” Though Forest Preserves represent substantial tracts of land and serve a uniquely important role in regional conservation efforts, and though these lands contain examples of the original habits though very little is regarded as exceptional quality habitat remnants (Packard 2004). Land that was acquired and set aside a century of more ago has not been managed for the preservation of the biotic communities until relatively recently. Grazing, timber removal, fire suppression and other influences has resulted in a rapid shift of these landscapes from the ecological conditions at the time they were placed under protection. Although the communities of the region have been biotically dynamic since the end of the glaciation, the rate of change is probably unprecedented, which a consequent loss of many of the flora and fauna the preserves were established to protect. Contemporary conservation efforts in the region are focused on the lands described above, and since conservationists regard most of the land as being in poor ecological condition, management has been proposed to restore at least some of these lands to ecological conditions that allow for the persistence of species and communities of significance from the perspective of the maintenance of the natural heritage and of the ecosystem services associated with high quality systems.
5. Ecological communities of the Chicago Wilderness region and their conservation status
The Chicago Wilderness classification recognized seven difference terrestrial community types: forest, savanna, shrublands, prairie, wetland, cliff, and lakeshore communities (Council 1999). Each of these community types is finely subdivided. Several of these sub-communities are recognized by the Nature Conservancy as critically imperiled globally, reflecting their global rarity and conservation significance. These include dry-mesic, mesic, and wet-mesic fine-textured-soil savanna, dry-mesic fine-textured-soil shrublands, wet-mesic woodlands, and wet-mesic sand shrublands. Many other sub-communities, including many of the prairies are classified in the Nature Conservancy’s next most significant conservation category, that of imperiled globally. In addition to these endangered plant communities the region also hosts animal assemblages of some conservation significance – in fact most rare plant communities have bird, reptile, amphibian and invertebrate assemblages of concern. Additional there are several rare mammal species targeted for conservation, including Franklin’s ground squirrel, Poliocitellus franklinii.
Although there are extensive openlands throughout the Chicago Wilderness region, approximately over 120,000 hectares in total, representation of the rarer community types are scarce. The Illinois Natural Areas Inventory identified 10,400 acres land with significant natural characteristics throughout the entire state (White 1978). This represents just seven-hundredths of one percent of the total land and water area of Illinois (Consortium 2006).
A recent report on the state of the natural lands in the Chicago region, evaluated by expert panels, concluded that the majority of the remaining natural areas surrounding Chicago are not healthy (Consortium 2006). Reasonably well characterized stressors, for instance fragmentation associated with urban development, non-native species invasion, overabundant deer populations and modified hydrological conditions and fire suppression contribute to the expert determination that overall, the region’s natural communities and animal assemblages remain in a declining or threatened state of health.
6. A rationale for biodiversity conservation in the Chicago metropolitan area?
As stated above the rationale for establishing a system of Forest Preserves around Chicago in 1913 was “for the purposes of the education, pleasure, and recreation of the public.” Though the land was set aside because of the perceived inherent importance of the flora, fauna, and scenery, nevertheless there is an early recognition in the statute creating the Forest Preserves that many benefits to the human population of the urban area redounds from this protection of nature. The Chicago Wilderness Biodiversity Recovery Plan, a blueprint for contemporary conservation and restoration efforts, written more than eighty years later, echoes this important principle (Council 1999). The stated goal of the recovery plan “is to protect the natural communities of the Chicago region and to restore them to long-term viability, in order to enrich the quality of life of its citizens and to contribute to the preservation of global biodiversity.” To emphasize: the purpose of protecting and restoring articulated here is both for the well-being of the region’s human population, as well as being a effort on behalf of global conservation – for people and for the sake of nature. The recovery plan proceeds to present the case for the conservation and the proposed management of the regions biodiversity in both of these categories. Though industries based directly on the direct use of native species in Chicago Wilderness are presently non-existent, nevertheless the plan foresees that the economic value of genetic material from such sources may become more prevalent. The provisioning of ecosystem services is presented in the plan as a second major indirect value derived from nature. A final direct use value is discussed namely the recreational and aesthetic value of these lands. In addition to the values that accrue directly to people from the protection of nature, there is recognition, consistent with the goal of the recovery plan, of the intrinsic value of these systems, “the feelings of ethical obligation to protect other species from extinction, religious values associated with cherishing the Earth and its inhabitants…” Though the discussion of the values of biodiversity conservation described in the recovery plan is generic it does include some striking local examples of the types of ecosystem services derived from the protection of ecosystems. For example, it cites the cost of flooding on the Des Plaines River for local governments and property owners to be $20 million per annum and associates this cost with the loss of wetlands which would otherwise ameliorate some of this flooding. Similarly the loss of habitat arguably necessitates the Metropolitan Water Reclamation District’s multi-billion dollar construction of the Tunnel and Reservoir Plan (TARP), known as the Deep Tunnel, the proposed solution to flooding in the Chicago.
Though the recovery plan reiterates many of the well known arguments in favor of conserving biodiversity these statements are important in the following respects: 1. the recovery plan was a relative early adopter of “ecosystem services” as a valuable framework in which to promote large scale conservation efforts and 2. the distinction between the different motivations promoting conservation has led recently to research attempting to evaluate the trade-offs and synergies in using ecosystem services or species protection as a guide for management planning (see ULTRA-Ex, below).
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