ORIGINAL PAPER The effect of target setting on conservation in Canada’s boreal: what is the right amount of area to protect? Yolanda F. Wiersma 1 • Darren J. H. Sleep 2 Received: 23 December 2016 / Revised: 26 October 2017 / Accepted: 4 November 2017 Ó Springer Science+Business Media B.V., part of Springer Nature 2017 Abstract Conservation of Canada’s boreal forest has been tied to various campaigns advocating specific area-based targets as part of a broader Systematic Conservation Planning (SCP) effort. Although target setting is an important component of SCP, it is known that the final outcomes of conservation plans are sensitive to the target chosen. There have been few systematic evaluations of how these outcomes change with targets. Here, we use distribution of terrestrial mammals in the Boreal Shield Ecozone of Canada to assess the effects of targets on conservation plans with individual sites that are predicted to be large enough to allow for species persistence. We examine three types of targets; percentage of landscape, percentage of umbrella species range, and minimum number of sites, to see how the final set (in terms of numbers of sites and percent of land) is affected and how well the final set represents the full suite of mammal species. We found a large discrepancy (164,000 km 2 ) in the land required to achieve minimal representation targets depending on the target used. The minimum number of sites target was most efficient and required only 1.25% of the ecozone, while the smallest percentage target that could capture all species was 10%. The use of an umbrella species (caribou, Rangifer tarandas) range was the least effective target, as several species could not be represented at any percentage of the umbrella species range. Thus, conservation planners working in the boreal should be mindful of the impacts their targets have on the final design. Keywords Conservation planning  Percent target  Biodiversity  Mammals  Species-at- risk  Effectiveness  Efficiency Communicated by David Hawksworth. & Darren J. H. Sleep dsleep@ncasi.org 1 Department of Biology, Memorial University, St. John’s, NL A1B 3X9, Canada 2 National Council for Air and Stream Improvement, Montreal, QC H3A 2R7, Canada 123 Biodivers Conserv DOI 10.1007/s10531-017-1461-2