Monarch migration mystery solved by Canadian researchersThe Canadian Press: A new Canadian study has apparently solved a mystery involving the migration habits of one of North America's most recognizable insects and may aid conservation efforts.
Scientists have been trying to understand why monarch butterflies east of the Appalachians showed up later in the year than those found west of the mountain range, which runs roughly from Atlantic Canada to Alabama. Researchers from the University of Guelph and Environment Canada have proved monarch butterflies migrate eastward over the Appalachians as they repopulate.
The butterflies recolonize 'multigenerationally,' meaning the generation that winters in Mexico flies northward, laying eggs west of the Appalachians, which then hatch into butterflies that head toward the eastern coast of the U.S. The finding is unusual because most recolonization patterns follow a more simple south to north pattern...
The monarch... is already famous for its long annual migration to Mexico. With this latest information scientists now know the insect's journey is even more spectacular than originally thought. Weighing only a few grams, the delicate butterfly battles harsh conditions to make it to the other side of the Appalachians. Researchers were able to make the discovery by analysing wing tissue and tracing the butterflies to their birthplaces...
Aside from solving a migration mystery, the study is significant because it will allow conservation efforts to be more effective... The study suggests the most productive monarch populations are in the Great Lakes and the mid-western United States... [Nathan] Miller.. one of two researchers who collected the samples... said monarch butterflies are surprisingly hard to catch. 'They are actually pretty fast and they're very aware of people.'
