Isotope mapping sheds rare light into migratory routes, natal origins of monarch butterflies

Pre-COVID-19 pandemic, University of Ottawa biology student Megan Reich enjoyed the road trip of a lifetime, crisscrossing the east coast of the United States in search of a specific thrill: Milkweed.

source https://phys.org/news/2021-09-isotope-rare-migratory-routes-natal.html