Climate change could threaten monarch mass migration | Mexico’s suitable monarch overwintering habitat could shift south as the climate changes in decades to come, researchers report in PLOS Climate.

>Climate change may threaten North America’s iconic mass monarch butterfly migration. 

>Every fall, millions of monarchs (*Danaus plexippus*) travel thousands of kilometers over North America as they leave their breeding grounds in Canada and the United States for wintering grounds in a [mountainous part of central Mexico](https://www.sciencenews.org/article/mexicos-forests-monarch-butterflies). The butterflies make the trek back north over multiple generations when temperatures warm in the spring and summer months, following the growth of milkweed (*Asclepias*), their preferred food source.

>But Mexico’s suitable monarch overwintering habitat could shift south as the climate changes in decades to come, researchers report February 25 in *PLOS Climate*. That could lengthen an already arduous journey and increase the energy required to make the trip.  

>That extra distance might push some individuals to stay in Mexico instead of continuing north, says Carolina Ureta, a biologist at the National Autonomous University of Mexico in Mexico City. “In this case, the species is not in danger because of climate change, but the migration might be.”  

[Read more here](https://www.sciencenews.org/article/monarch-butterfly-migration-climate) and the [research article here](https://journals.plos.org/climate/article?id=10.1371/journal.pclm.0000802&utm_source=pr&utm_medium=email&utm_campaign=plos006).