Monarch Butterfly Facts, Migration & Climate Change
December 3, 2015.
Monarch butterflies are truly amazing!
They weigh a fraction of an ounce and fly an astonishing 1,500 miles each spring through storms, clouds and predators to grace the summer fields of the United States and Canada.
They’re also worth saving.
They’re numbers are declining and we need to do something about it fast. In fact, they’re another example of why we need to be reducing our carbon footprint – every day.
The Monarch butterfly, with its bright orange/yellow colors and elegant black trimmed, white-spotted wings, has been until recently a familiar sight in fields and yards all across North America. However, over the last decade their numbers have been dramatically declining, and there are a number of possible reasons including:
- The loss of milkweed – the only plant that Monarchs lay their eggs on, and monarch caterpillars depend on it to grow and develop. Milkweed plants are disappearing due to both population expansion and adverse land management. Drought conditions linked to climate change - especially in California - have further reduced milkweed abundance.
- The use Insecticides and herbicides. These are used to control insects and weeds in areas ranging from large agricultural fields to household lawns. These chemicals may be poisoning monarchs and other invertebrates.
- The decline of overwintering habitat. In California this is happening due to community expansion and development. In Mexico overwintering sites are diminishing due to excessive logging.
- The impact of climate change on local environments. Scientists have recently discovered that counter intuitively, it is the 'chill' of their winter habitat that ‘orients’ them to fly north in the spring. Overwintering in the warmer conditions forecast for the future could insufficiently reset their internal compass.
We speak of overwintering habitats because one of the unique things about all Monarchs is that in the late summer and fall, they migrate to warmer places. In the west they fly to forested over-wintering sites along the California coast. East of the Rockies, they begin moving south in August in what is in some cases is an astonishing 1500 mile journey to very specific mountain forests of Mexico.
There are plenty of things we can do to improve the environment for Monarchs--from planting milkweed to joining in the citizen science that helps us better monitor their health and understand their use of habitats.
At ClimateStore, we’re keen on helping all species in the face of climate change and hope you are too.
Wondering how you can help? Check out these great organizations who are helping monarchs.
- The Monarch Joint Venture A partnership to conserve Monarch migration
- Xerces Society for Invertebrate Conservation
- MonarchNet.org - The North American network of monarch butterfly monitoring programs
And there's good news too - it turns out you can help Monarchs from your home by simply starting to live more sustainably - by conserving energy, saving water and getting others engaged in low carbon living. Better living for a better world.