The Plight of Florida’s Monarch Butterflies

For the last few years, I have been able to participate in South Florida seasonal butterfly counts led by entomologist Dr. Marc Minno. During this research, where we trek through marl prairies, roadways, forest and swamps, I am always excited to see one of the iconic orange and black butterflies and perhaps one of the best known, the monarch. In recent butterfly surveys in Southwest Florida, we have seen representatives of many species of butterflies. In our survey, we saw twenty different ones represented. The issue is the quantity of these beautiful beings is declining and we only saw one monarch during the whole day.

Monarchs provide creative inspiration for many. There are movies made about them, like Flight of the Butterflies. In 2012, Barbara Kingsolver wrote a book called Flight Behavior. Legislation was introduced to make the monarch butterfly the national insect of the United States, although it failed.

There have been scientific studies on this species as well. The International Space Station hatched some on board in 2009. They were also the first to have their genome sequenced which provided data on their migration.

I had the chance to interview my friend, Dr. Marc Minno, about monarchs and I became very concerned. Although there are studies, popular books and media surrounding them, there is an issue here. Florida is very important when it comes to monarchs but there is limited support for them in the state. Dr. Minno said, “Florida is a very special place because we have the only natural population of resident monarchs in the entire USA. Yet very little study of monarchs is being done in Florida because funding agencies have concentrated on the Midwestern states. We need to do better in Florida!” 

Since the death of noted ecologist and entomologist Lincoln Brower in 2018, very little research has been done on monarchs in Florida. For over six years Brower studied monarch butterfly conservation. In the 1980s he assisted conservation groups in Mexico. There is some limited hope, but things need to be better to increase numbers. There has been some tagging and tracking research being done by Nick Bodven and associates in Fort Myers for several years now. The Florida wildflower license plate was changed to incorporate a monarch butterfly. Sales dollars raised support all pollinators in the state.

In addition to our resident Florida monarchs, we also have migratory ones that come here in the spring and leave in the fall. All the migrating monarchs traveling east of the Appalachian Mountains pass through our state. Many gather at St. Marks Wildlife Refuge on the Gulf Coast where they have a festival celebrating them in October. 

Monarchs are native throughout tropical and temperate areas of North America, South America, and the Caribbean. North American monarchs are unique as they are the only ones that migrate.

Now for a little more information about these beauties before a more stark reality. In addition to enjoying their vibrant colors, monarchs are symbolic to some as signs of transformation, hope and rebirth. They represent endurance, strength or even evolution and a sign of spiritual change. In Mexico, the Day of the Dead or Día de los Muertos, occurs upon the butterfly’s migration to Mexico. The butterflies are believed to hold the souls of the deceased.

The origin of the butterfly’s name is attributed to King William the III of England who was known as the Prince of Orange, which is the monarch’s primary color. 

In different regions butterflies can also be called Milkweed, Common Tiger, Wanderer, and Black-veined Brown Butterflies. Males are slightly larger than females and have a black spot on a vein on each hindwing. The spots have pheromones in them that attract mates. Females are often darker and have wider veins on their wings.

Distinctive patterns and colors alert predators that they are poisonous and that they do not taste good. The milkweed plants they feed on as caterpillars arms them with poisons called cardenolides that are used as a defense against predators. After the caterpillar becomes a butterfly, the toxins move to other parts of their body such as the wings or abdomen. 

Like all butterflies, these creatures have a four-phase life cycle from egg to butterfly. Eggs can develop into butterflies in as little as a month. As they grow from egg to butterfly, they are susceptible to disease, weather, predation and parasites. In Florida there is a major cause for concern for parasites. Less than 10% of eggs or caterpillars become butterflies.

Scientists have not figured out how these butterflies can find the same overwintering sites in Mexico. How do they navigate on their journeys? The sun is used to keep them on course with an internal magnetic compass to help them on cloudy days. In late summer and fall, monarchs start their flights south across most of North America.

Now for the dire facts. Monarchs are at great risk. In 1990, the U.S. population of monarchs was thought to have declined by at least ninety percent. Brower and others proposed that they be listed as Endangered by the U.S. Fish and Wildlife Service. In 2022, the International Union for conservation of nature added the migrating monarchs to a “red list” of threatened species. This means that they are categorized as endangered and are two steps from extinction.

The decline of milkweed is a major reason for the population decline. Milkweed is the only plant where Monarchs lay their eggs. It used to be seen growing around farms, but it has been removed with the use of pesticides and increased mowing.

Climate change impacts these insects also as they are very sensitive to both weather and temperature changes. It may alter when they reproduce or know when to migrate. They also might die with big changes in temperature.

The latest research seems to indicate that monarch breeding still may be okay, but that the adults are not making it to the overwintering sites in Mexico. U.S. Fish and Wildlife and associated agencies like National Fish and Wildlife Foundation have spent millions on planting milkweeds in the Midwest to combat issues. These agencies have largely ignored Florida.

There have been larger scale efforts to better manage the land for pollinators, protect habitat, replenish milkweed, raise awareness and do more research to get a better understanding of these beautiful creatures. Some of the activities are beneficial and some have questionable results.

One group, the citizen volunteer supported Monarch Watch program, tracks fall migration of the monarch. It is a nonprofit based in Kansas that provides education, conservation, and research on monarchs. They offer citizens milkweed plants for their Monarch Waystations at a nominal fee.

Public concern has driven people to plant native milkweeds in their areas. Nonnative milkweed is being planted in butterfly gardens. This could create new locations where the butterflies might overwinter that would stop migration from the Gulf Coast areas. It could also increase the presence of the scary Ophryocystis elektroscirrha parasite (OE). The OE parasite is usually of low occurrence except in southern Florida where there are mostly resident monarchs.

Sanctuaries have been created in Mexico to limit habitat destruction. These sites draw tourists but also have been shown to have a negative effect on survival.

The media publishes many headlines surrounding the decline of monarchs. People are told to grow as many of these insects from their homes and to release them. Some entomologists think that this may lead to genetic issues and disease spread. This might encourage the spread of the OE parasite into the wild and limit migration due to lower health levels of home raised butterflies.

There is some hope. In 2022, The International Union for Conservation of Nature added the migratory monarch butterfly to its red list of endangered species. The US Department of Agriculture initiated a “SAFE” program that pays farmers to not farm specific land.

Agriculture companies are being asked to not use land or pesticides to encourage monarch breeding. There are some government agencies encouraging roadside and power line pollinator habitat creations. This is a double edge sword as roadways create a lot of monarch deaths. However, any additional habitat is better than none.

The creation of “monarch waystations” and butterfly gardens may help if the right types of milkweeds are planted.

More focus and money needs to be spent on Florida monarchs if we want their populations to thrive and increase. I would love to report back on seeing many monarchs during our next butterfly count you and share the happiness!

There are several good resources where you can find more information on monarchs including the National Audubon Society Field Guide to North American Butterflies. For Florida specific books, there is the popular Florida Butterfly Gardening by Marc C. Minno and Maria Minno as well as Florida butterfly caterpillars and their host plants, also by Dr. Minno.

There are ways that Floridians can help save monarchs. By purchasing the Florida State Wildflower license, which features a large monarch, funds are given for research, education and planting. The National Wildlife Federation has state affiliates that offer resources, tagging programs and support for legislative solutions to aid these beautiful creatures.