Prioritizing Illinois Protected Lands | Stream Ecology Lab | Illinois Natural History Survey

Illinois Protected Lands include parks, wildlife areas, wilderness areas, wildlife refuges, recreation areas, nature reserves, historic sites, forests, and others that serve a wide variety of roles (e.g., hiking, hunting, nature study) and have various levels of permanence (e.g., 30-year easement, permanent easement, National Forest). Each type of protected land is designed to confer specific conservation benefits (e.g., conservation easement, wildlife refuge, city park) by considering site-specific Natural Community Types (NCTs) and Illinois Species in Greatest Conservation Need (SGCN). However, protected lands are growing increasingly isolated due to landscape modification and require dedicated stewardship to ensure conditions continue to meet site conservation goals and purposes. Efficient allocation of personnel and financial resources is critical for effective delivery of stewardship and conservation efforts within Illinois protected lands.

Map of Illinois showing vulnerability of INPC to anthropogenic disturbance by natural division (greatest magnitude). — Figure 1. Relative vulnerability of Illinois Nature Preserves Commission (INPC) sites within Natural Divisions. Vulnerability is quantified as the highest magnitude present across the threats at a site. All threat variables were rescaled on a 0-10 scale based on the percentile of their values at each site compared to all values for that threat across the state, 10 being all threat values that were greater than 90% of all other occurrences of that threat across the state, and 0 being the absence of the threat. These percentile-rescaled values were used to quantify the magnitude of the effect of each threat at a site.

Map of Illinois showing vulnerability of BSS to anthropogenic disturbance by EDU (greatest magnitude). — Figure 2. Relative vulnerability of Biologically Significant Stream (BSS) segments within Ecological Drainage Units. Vulnerability is quantified as the highest magnitude present across the threats at a segment. All threat variables were rescaled on a 0-10 scale based on the percentile of their values at each segment compared to all values for that threat across the state, 10 being all threat values that were greater than 90% of all other occurrences of that threat across the state, and 0 being the absence of the threat. These percentile-rescaled values were used to quantify the magnitude of each threat’s effect at a segment.

This project aims to prioritize Illinois Nature Preserves, Illinois Natural Area Inventory sites, and Biologically Significant Stream segments identified as Focus Areas within the Illinois Wildlife Action Plan Streams Campaign for protection and stewardship based on NCT quality and SGCN presence. Subnational conservation status ranks (S-ranks) will be developed for Illinois NCTs and SGCNs, and protected lands of interest will be prioritized based on their statewide rarity-weighted richness, biodiversity, and viability under anthropogenic disturbances. Project tools include priority-ranked species and natural communities, site lists, and maps of priority-ranked protected lands. Project output thereby identifies key aquatic and terrestrial locations for conservation work, provides common assessment standards for evaluating current statewide protection efforts, and informs conservation managers’ decision-making and efforts to meet regional conservation goals.

Map of Illinois showing INAI rarity weighted richness of S1 and S2 wildlife. — Figure 3. Illinois Natural Area Inventory (INAI) sites grouped from lowest to highest conservation priority by rarity-weighted richness of critically imperiled/imperiled (S1/S2) state-listed wildlife species and all additional fish and mussel SGCN. High-priority sites have the highest rarity-weighted richness values relative to all sites statewide.