New records for Eastern Mosquito Fern (Azolla cristata, Salviniaceae) in Canada
Keywords:Azolla cristata, Eastern Mosquito Fern, climate change, native biodiversity, pteridophyte, Frontenac Axis, Ontario, Quebec
We report a cluster of Eastern Mosquito Fern (Azolla cristata, Salviniaceae) populations in five watersheds within a 56-km2 area of Leeds and Grenville County, Ontario. Some of the recently discovered populations were immense, one containing over two million individuals in 2016. These eastern Ontario populations are persistent, having been observed in situ continuously for four years. One population was confirmed after an apparent absence of at least 30 years and another was reported as present (or at least recurring) for approximately 50 years. We observed that Canadian A. cristata is capable, at least experimentally, of overwinter dormancy and subsequent renewal. Azolla cristata in eastern Ontario and western Quebec appears to represent naturally (if sporadically) occurring populations, likely transported from adjacent northern New York populations by migratory waterfowl. These natural occurrences are expected to be more frequent as climate change continues to reduce environmental barriers to the northward establishment of this and other southern taxa.
Copyright for Canadian Field-Naturalist content is held by the Ottawa Field-Naturalists' Club, except for content published by employees of federal government departments, in which case the copyright is held by the Crown. In-copyright content available at the Biodiversity Heritage Library is available for re-use under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 (CC BY-NC-SA 4.0) licence. For usage of content at the BHL for purposes other than those allowed under this licence, contact us.
To request use of copyright material, please contact our editor, Dr. Dwayne Lepitzki: editor -at- canadianfieldnaturalist -dot- ca