The primary organizational units for this action plan are 'landscape features,' which are broadly defined as 'components of the overall landscape used by wildlife, differentiated by vegetative, geologic, hydrologic, and structural elements, which may occur at various scales.' Landscape features may be equivalent to ecosystems, they may incorporate multiple ecosystems, or they may be components of ecosystems, including isolated structures within a diverse matrix. Different landscape features are often divergent in scale and are not necessarily spatially exclusive; together they therefore provide the variety of characteristics, both structural and spatial, that are essential for wildlife. They include broad ecosystems such as prairies and ponds, as well as small-scale structural characteristics that species require, such as snags or gravel substrates (Fig. 1). Where landscape features overlap, they act as multiple variables that together describe a place on the landscape.

Figure 1. Example of spatial distribution of landscape features.
Click image for a larger version.

Landscape features provide a common denominator between existing classifications used by conservation partners in Michigan. Existing classifications include Natural Communities (Michigan Natural Features Inventory 2003), U.S. Environmental Protection Agency (USEPA) general wetland types (USEPA 2005a), River Valley Segments (Seelbach et al. 1997), and the multi-scaled vegetation inventory (Donovan et al. 2004) used by the Michigan Gap Analysis Project and the DNR's Integrated Forest Monitoring, Assessment and Prescription (IFMAP) system. The landscape features are not proposed as a new classification system, but as an organizing tool that can be used by any planner or manager to focus conservation efforts at a relevant spatial scale. They describe current, rather than potential or desired, conditions on the landscape, and as a result, include human-influenced systems that are used by wildlife, even if they do not represent the preferred habitat.

The use of existing classification systems was considered; however, no single system available at the time of action plan development was sufficient for the purposes of the document. Existing classification systems were either too fine or too coarse in scale, did not include heavily human-influenced systems that wildlife use (e.g., agricultural lands), or did not include key characteristics important to wildlife. Additionally, the action plan needed a coarse filter that could be applied in a similar manner for both aquatic and terrestrial systems, and no such classification system was available. Furthermore, one objective of this action plan is to provide location/distribution maps of habitats used by SGCN to build a knowledge base for all conservation partners in Michigan, and to provide easily measured metrics for long-term monitoring. Therefore, the organizational unit for the action plan must be as spatially explicit and comprehensive as possible. Few classification systems have currently been mapped for the entire State. Even though landscape features are not necessarily spatially exclusive, most can be individually mapped, and the conditions of many are routinely monitored as part of ongoing statewide inventories and assessments.

Throughout the action plan, use of the terms 'habitat' and 'habitat-type' is minimized, because these terms refer to the needs of specific species and may be confusing when used in a broader context. Instead, the term 'landscape feature' is used to identify components of the landscape used by wildlife, the conditions of which can be managed and monitored. The WAP identifies 43 terrestrial and 48 aquatic landscape features within broad categories (see Aquatic Landscape Features and Terrestrial Landscape Features for complete lists and descriptions).

Table 1. Basic landscape feature framework

The bulk of this document addresses each individual aquatic and terrestrial landscape feature within each lake basin or ecoregion, respectively, of the defined ecological frameworks. This information, in the Landscape Feature Summaries, will be most valuable to conservation partners working within a particular region or at a specific site, regardless of the ownership type or spatial extent of the area of focus. Each of these landscape feature summaries includes information on distribution, location, general condition and associated SGCN for a particular landscape feature in a particular region. Each summary identifies threats to the landscape feature and associated wildlife and recommends conservation actions to address those threats. Additionally, research and survey efforts needed to address gaps in knowledge are identified. Each summary also outlines the monitoring necessary to assess conditions and trends associated with each landscape feature and to evaluate the success of conservation actions.