An Assessment of the Geographic Distribution and Status of a Rare Dragonfly, Rhionaeschna mutata, at the Northwestern Edge of Its Range

Abstract

Rhionaeschna mutata (Hagen) (Spatterdock Darner) is a rare North American dragonfly, most widely distributed in the eastern US. In 2009, a reproductive population was found in 2 ponds in eastern Minnesota, establishing a substantial northwestern range expansion. We assessed the geographic distribution of the Spatterdock Darner in the region to inform conservation planning for this species. Using previously defined habitat criteria, we identified potential reproductive ponds in the ecoregion with GIS. In 2015 and 2016, we used multiple methods to survey 25 ponds for Spatterdock Darner nymphs, adults, and exuviae. We found no Spatterdock Darners in the region, despite intensive survey efforts targeted at ponds that met the habitat criteria. The Spatterdock Darner may be present in this water-rich region, but was undetected by our efforts, or a local extirpation may have occurred, possibly linked to recent fish colonization in one of the original reproductive ponds.