Tag Archives: Oyamel Firs

Monarch Strong

On February 26th, 2016, our partners in Mexico released that their estimates of the overwintering monarch butterfly population has increased by 255%! This year, monarchs are inhabiting approximately 10 acres of oyamel fir forests, which is up from 2.8 acres last year. This is a great accomplishment for the iconic species, but more work is needed to restore the eastern monarch population to historic numbers.


Monarchs cling to each other in dense groups during the winter months. Photo Credit: Pablo Leautaud, Creative Commons (https://flic.kr/p/atiVia)

Best known for their extensive 2,000 mile migration, monarchs travel from southern Canada and the United States every fall to their overwintering home in the Monarch Butterfly Biosphere Reserve in Mexico. Here, the monarchs gather by the millions in oyamel fir trees where the weather is mild enough to survive the winter. This dense gathering also allows scientists to accurately estimate the monarch population, based on the total area they occupy. It is important to know the health of the monarch butterflies because they serve as an indicator for other pollinating insects. Pollinating insects are crucial to the success of our agricultural crops and native wildlife!


This monarch has been tagged for research to learn more about the monarch migration! Photo Credit: Monarch butterflies by Joanna Gilkeson/USFWS.

On their return flight to the United States and Canada in early spring, monarchs utilize native wildflower meadows and milkweed plants along the way. These areas allow monarchs to reproduce so the newest generations can continue north to their summer grounds. ¬†Milkweed is the monarch’s host plant, meaning they need these plants for survival. The Service has been diligently working to improve this monarch habitat and increase the overall population. Although we have made significant progress this past year, our job is not done! Help save the monarchs by reducing your use of pesticides and planting more milkweed and wildflowers!

Click here to learn more about how you can protect the monarch butterfly and other pollinators.