Riverine connectivity, upstream influences, and multi-taxa representation in a conservation area network for the fishes of Michigan, USA PETER C. ESSELMAN a, *, MINAKO EDGAR b , JASON BRECK b , ELIZABETH M. HAY-CHMIELEWSKI c and LIZHU WANG d a Department of Zoology, Michigan State University, 288 Farm Ln, Room 203, East Lansing, MI 48824, USA b Institute for Social Research, 330 Packard St, Ann Arbor, MI 48109, USA c Michigan Department of Natural Resources, 26000 West Eight Mile Rd, Southfield, MI 48034 d International Joint Commission, P.O. Box 32869, Detroit, MI 48232 ABSTRACT 1. Fisheries resource conservation is a national priority in the USA because of the high economic and social value of fish to society. Landscape spatial planning to identify focal areas for conservation of fishes is an important step to targeted site-level interventions to protect or restore fish habitats, because it can provide a strategic approach to guide conservation efforts. Computerized spatial planning algorithms that identify networks of sites that meet user- specified targets for species representation indicate locations with favourable conditions for fish protection. 2. Here a commonly used systematic planning software, Marxan, was employed with previously published fish range and human disturbance predictions to define a network of conservation focal areas for rivers in Michigan. This network focused on large-bodied species, small-bodied species, species of greatest conservation need (SGCN), and all species together. 3. Depending on the scenario, the networks identified comprised between 14 and 20% of Michigan stream length in over 1700 focal areas ranging from 6 to 8 km in average length. Mean focal area sizes were much larger for the Upper Peninsula than the Lower Peninsula. Approximately 35% of the focal areas defined flowed through already protected lands, but less than 5% had upstream catchments that were secure within protected areas. There was a 45% overlap in the focal areas selected for the large- and small-bodied fish and SGCN. 4. The rivers defined may serve as appropriate core areas for fish conservation. Resultant maps show locations with a high natural potential to conserve all of Michigan’s native fish species, and can serve as a reference point for regionalization of comprehensive state-wide planning efforts for fish conservation. It is recommended that this study is followed up with additional planning steps to define complementary conservation zones for protecting the functionality of ecosystems to support fishes, and to forward methods for incorporating spatial metapopulation dynamics into the planning process. Copyright # 2012 John Wiley & Sons, Ltd. Received 28 November 2011; Revised 26 May 2012; Accepted 23 July 2012 KEY WORDS: river; stream; biodiversity; protected areas; conservation evaluation; fish INTRODUCTION Fisheries resource protection is a national priority in the USA because of the high economic and social value of fishes to society. Nonetheless, many US fish species are depleted or locally extirpated in portions of their ranges owing to human activities that damage habitats, facilitate non-indigenous *Correspondence to: P.C. Esselman, Department of Zoology, Michigan State University, 288 Farm Ln, Room 203, East Lansing, MI 48824, USA. E-mail: pce@msu.edu Copyright # 2012 John Wiley & Sons, Ltd. AQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS Aquatic Conserv: Mar. Freshw. Ecosyst. 23:7–22 (2013) Published online 1 October 2012 in Wiley Online Library (wileyonlinelibrary.com). DOI: 10.1002/aqc.2279