We used double sampling to estimate densities of Rusty Blackbird (Euphagus carolinus) nests among boreal wetlands in Anchorage and Tanana Flats, Alaska, 2007–2008. We also assessed habitat selection by examining the number and location of nests relative to the availability of various wetland types. We rapidly surveyed 78 sample units for adult Rusty Blackbirds and intensively searched for nests in a subset of 55 units to determine actual numbers of nests. Rapid surveys detected 97% of the 75 nests when we restricted counts to pairs and lone females. They overestimated nest numbers by 17% when we included in the counts lone males, which sometimes made long flights within and between sample units. Nest densities in sampled wetlands averaged 2.2 and 3.4 nests km ² in Anchorage and Tanana Flats, respectively, surprisingly similar despite wetlands being rare in Anchorage. An abundance of wetlands made identifying important breeding habitats difficult on the Tanana Flats, where blackbirds used most wetland types in relation to their availability and avoided wetlands with low shrubs. Habitat selection was clearer in Anchorage, where ponds, lakes, and wetlands with emergent vegetation were positive predictors of nest abundance. In this area blackbirds also selected forested wetlands and avoided upland habitats for nest sites. An affinity for open water has been noted throughout the Rusty Blackbird's breeding range. Research is needed to understand whether this affinity is due to specialized food requirements and to assess whether this species is vulnerable to widespread drying of wetlands across boreal Alaska.