Written by Bailey Smith
The Monarch butterfly is without a doubt the most easily recognized butterfly species for the citizens of Ohio. Right now, between July 27th- August 4th, is the third annual International Monarch Monitoring Blitz! This citizen science event invites anyone from the United States, Canada, and Mexico to join the search for monarchs around their homes, parks, and green spaces. Participation in this event is simple, both for those who love a good search and for those that love butterflies. The mission of the Monarch Larval Monitoring Project (MLMP), “is to better understand the distribution and abundance of breeding monarchs and to use that knowledge to inform and inspire monarch conservation.”
The Monarch Larval Monitoring Project is interested in observing the life cycle of monarchs at each of their generations to better understand patterns in the monarch population. Monarchs are unique in that they undertake a long distance migration. The migration is made up of multiple generations of butterflies. Contrary to popular belief, monarchs that we see during Ohio summers will only live 2-5 weeks at a time. It is the monarchs that are reared in Ohio in the late summer and fall that will make the migration south all the way to fir forests that are located at high elevations in Mexico. These will live up to 9 months on average. There they will overwinter before they begin the way back to the north, laying eggs in increments by generation. Through this you can see how the lifecycle of the monarch is dependent on available habitat throughout the path of migration.
Monarchs are specialists. They MUST have milkweed as the host plant for their eggs and caterpillars. For each generation, the life cycle of a monarch butterfly starts as a tiny egg on the underside of a milkweed leaf. There the egg will reside for 3 to 5 days and just before the caterpillar emerges the egg will turn from a creamy white color to dark. The larval stage of their life cycle begins as the caterpillar emerges and begins to eat the milkweed’s leaves. One monarch caterpillar can eat up to an entire milkweed plant!
The larval stage consists of 5 subphases called instars. The first four instars will last 1 to 3 days each. During the first instar the tiny greenish gray caterpillar is difficult to spot. After molting, the second instar caterpillar can be seen more easily and the stripes become more evident. At the third instar, the caterpillar will drop from the leaf and curl into a tight ball if disturbed, and during the fourth instar caterpillars develop a distinct banding pattern. The fifth instar is the longest, lasting from 3 to 5 days, and the large caterpillar can be easily seen devouring the flowers and leaves of the milkweed plant.
The caterpillar then prepares to enter the pupa stage by starting to spin a silk mat from which the caterpillar will hang suspended in a J shape. The exoskeleton “skin” will split to reveal a completed green chrysalis adorned with jewel-like gold accents. Once the chrysalis is formed, this stage will last around 8 to 15 days. At the end of the pupa stage, the chrysalis will show the orange and black patterns of the wings developing inside. Soon the butterfly will emerge from the chrysalis where it will wait a few moments for its wings to dry before flying away to start its adult life. Adults can use many species of plants as a nectar source.
The population of monarch butterflies are at a decline due to habitat loss in many areas of their migration route, pesticide usage, and other limiting factors. On their wintering range, protection of the fir forests in the Michoacan state of Mexico, along with re-forestry efforts, has helped. Actions that we as a community can take to do our part along the monarch journey are to plant several native varieties of milkweed (such as swamp milkweed or common milkweed) in backyards and other green spaces to increase the availability for monarch eggs and larvae. We can also plant native plants that flower throughout the growing season to provide nectar sources for adult butterflies. You can even help by tagging butterflies in the north so that they can be spotted and recorded as they make their journey south in the fall!
Want to get involved? It is as easy as picking a patch of milkweed that you can monitor! To register as an individual volunteer or complete the online training visit the University of Minnesota Monarch Lab’s website. There you will be able to get detailed directions and information guides for better monarch identification. You will also be able to find datasheets for the specific activity you choose within the project, as well as an online data entry page. Participation in projects like the Monarch Larval Monitoring Project will provide you with a better understanding of wildlife in your area. For more information about the Monarch Larval Monitoring Project and the Blitz or to register to participate in your area visit: https://monarchlab.org/mlmp/
When participating in this project or just out enjoying the great outdoors; don’t forget to post your observations on iNaturalist. Online platforms like these make citizen science possible by making information more available to researchers and increases the data we have on different species!