What would the world be like if our prettiest pollinators went extinct? A study published in the journal, Forest Ecology and Management, revealed that monarch butterflies (Danaus plexippus) may not have a suitable habitat to overwinter starting in 2030, meaning that the butterflies will not have anywhere to stay when they migrate for the winter.
The oyamel fir trees (Abies religiosa) in Mexico are the preferred tree for monarch butterflies to overwinter on, but climate change is rapidly reducing the trees’ niche. A possible solution to the trees’ decreasing niche lies in assisted migration of the trees to higher altitudes as the climate shifts over the next several decades.
In other words, the trees can be physically relocated 300 to 400 meters higher in altitude to compensate for the projected climate change in 2030.
Over 100 million monarch butterflies overwinter on the oyamel fir trees in the Trans-Mexican Volcanic Belt. Thus, the changing climate that endangers the trees in this area, also endangers the monarch butterflies that overwinter in those trees.
The oyamel fir trees’ niche is projected to decrease by 69.2% in the decade surrounding 2030, and by 2090 96.5% of the trees’ niche will have disappeared from the Trans-Mexican Volcanic Belt.
The assisted migration of the oyamel fir trees encompasses a few risks based on the study’s model. The study states that the trees have a risk of frost damage if they are moved too soon with the current climate, and many of the sites targeted for the assisted migration have poor soil quality.
In addition to those risks, the study explains that there is no guarantee that the monarch butterflies would accept the migration of the trees.
Despite these risks, the study concludes that assisted migration may be the best option, considering that in 2090 the projected climate (a 3.7˚C temperature increase and an 18.2% precipitation decrease) will no longer be suitable for the oyamel fir trees or the monarch butterflies at the current altitude.
Climate change affects ecosystems all over the world, but there is still time to protect the oyamel fir trees and the monarch butterflies from having their niches destroyed.