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ABSTRACT 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., 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., 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., 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. [ABSTRACT FROM AUTHOR]

Although localized effects of individual dams on stream fish assemblages have been relatively well-studied, less is known about the effects of multiple dams within a stream network on fishes and the patterns that emerge when the combined effects of individual and multiple dams are viewed across entire river basins, ecoregions, and states. This study evaluated multiple stream network fragmentation metrics representing localized (e.g., distance-to-dams) and cumulative (e.g., total upstream reservoir storage) dam influences on streams in Michigan, Wisconsin, and Minnesota, developing an approach for identifying suitable fish indicators of dam effects. We used change point and correlation analyses to determine associations of stream fish catch per unit effort and various stream network fragmentation metrics with data from more than 2000 fish survey sites stratified by stream size, thermal regime, and ecoregion. Of the identified indicator species, predominantly warmwater, large river, and/or lentic species were positively associated with stream network fragmentation, whereas cold and coolwater lotic species were negatively associated with fragmentation. These results suggest a combination of downstream thermal effects and upstream influences from impoundments generated by dams. Variance partitioning analyses based on identified indicator species revealed greater upstream-dominated dam influences in headwaters than mid-sized streams, and a greater relative influence of dams vs. other non-dam anthropogenic influences in cold streams than warm streams. Overall, a combination of localized and cumulative fragmentation metrics, as well as upstream and downstream-oriented measures, were influential in indicator species responses, emphasizing the importance of selecting a diversity of fragmentation metrics when assessing effects of dams on stream fishes. Understanding multiple dam influences on stream fishes, including localized effects from individual dams and cumulative effects from all dams within a river basin, would provide useful information for a variety of management activities, including dam operation and dam removal prioritization. Dams significantly affect conservation and management options for stream fishes, with identification of multi-scale dam influences on fishes being critical to restoration and maintenance of aquatic biodiversity throughout the world. [ABSTRACT FROM AUTHOR]