Bioluminescent Wonders in Michigan

by Emma Kull, MNA Communications Intern

Fireflies are a well-known member of the beetle family that live all across the United States. Including the estimated 170 species in North America, there are over 2,000 species of fireflies worldwide on every continent except Antarctica. Their wondrous bioluminescence is a special sight to behold, admired by children and adults alike. Michiganders may recall summertime memories of running around their backyard with joy searching for these creatures, waiting for the next tiny glow to illuminate the night. As it turns out, that unique glow is not just a feature of the adult firefly: the firefly eggs and larvae can glow too!

Firefly adult beetle at MNA’s Clifford R. and Calla C. Burr Memorial Nature Sanctuary. Photo by Angie Adamec.

Fireflies begin their lives as small eggs, sometimes clustered together with up to 100 other eggs. These firefly eggs can be found in moist soil or vegetation during the summer where they develop for about a month. For some species of firefly, these eggs will emit a dim glow.

As the summer turns to fall, the firefly eggs transition to their next stage of life and become larvae. They live as larvae throughout the fall, feeding on insects, worms, and snails. As the winter approaches in Michigan, they survive the cold temperatures by burrowing into the ground where they stay dormant for several months. The larvae then emerge from the ground in spring. Firefly larvae, much like they did as eggs, can produce light. However, unlike firefly eggs and adults, which may or may not emit light, all species of firefly larvae glow. Hence, they are often referred to as ‘glowworms’ in this stage of their lives. The naturally occurring chemicals in firefly larvae give them a bitter taste, making them undesirable as prey. Thus, some scientists believe glowworms are bioluminescent to warn potential predators of their bad taste. The beauty of the glowworm is only magnified by the rarity of actually encountering one, as they are more difficult to stumble upon compared to the adult fireflies that dance through the night sky.

Firefly larvae emit a bioluminescent light to warn potential predators of their unsavory taste. Photo by Alexandra Karelian via Adobe Stock, @karelian –

The glowworms pupate later in the spring and emerge as adult fireflies, on average, a few weeks after pupation. Once fireflies have reached their adult stage, they only live for a few weeks to a month. Therefore, a firefly’s main goal is to reproduce within that short lifespan. As adults, some fireflies produce light and others do not. Those that do typically only illuminate for mating proposes, yet they have also been observed to do so for other reasons, like defending territory. The male firefly will fly around, flashing a specific light pattern to attract a mate. The female will then flash her own signal, indicating her interest in that male. Adult fireflies that do not produce light instead use pheromones to find mates and reproduce.

As many have never had the chance to see a firefly in a pre-adult stage, it may be surprising to discover that fireflies begin glowing so early. Those who have witnessed one are certainly lucky!

Interacting Safely with Michigan Wildlife

by Jayli Husband, MNA Communications Intern

Michigan is filled with many interesting landscapes such as lakes, forests, marshes, prairies, as well as a popular destination for sand dunes and beaches. With this diversity of natural areas to explore, there are many different species that can be spotted throughout Michigan. With spring in full bloom throughout the state, it is important to be conscious of the native wildlife that may soon be emerging within our forests and neighborhoods and how to properly interact with them. Each spring, there are a number of wildlife encounters throughout Michigan that should be taken with caution.

As temperatures rise, reptiles such as snakes will become more prevalent because they hibernate during the cooler months. After a snake has been clearly seen, it is important to keep a safe distance so that the snake does not feel threatened, this way, they will not react. Snakes will most often avoid humans, in fact, 17 of 18 Michigan snake species are harmless to people. However, if you happen to encounter the Eastern massasauga rattlesnake (Michigan’s only venomous snake), it is best to back away, and if it is staying in a community setting such as a park or backyard have it removed by a professional.

Eastern Massasauga Rattlesnake photo by Zach Pacana.

Unfortunately, the Eastern Massasauga Rattlesnake is now a threatened species because of the loss of habitat, thus, it is important to report any sightings to help conservation and DNR tracking efforts in Michigan. Snakes are very important in their ecosystem; they maintain balance in by eating pests such as mice and rats, and are also important prey for hawks, and other larger carnivores.

In addition to reptiles and amphibians popping back up, coyotes are also a common sight in the spring throughout Michigan. Coyotes can be spotted throughout the year, but it is important to know how to handle monitoring them due to increased activity during mating season. Like many animals, coyotes tend to avoid humans, but it is important to keep watch on small pets and make sure that they are supervised when outdoors if a coyote is spotted nearby. Additionally, coyotes have a great sense of smell, so it is helpful to keep food or smelly garbage contained when it is placed outdoors. To prevent a coyote from moving closer, they can often be deterred by scaring them through loud noises and aggressive hand waving. Coyotes are important for ecosystems as well because they are a keystone species. As a keystone species, coyotes help control the populations of prey species such as rabbits, rodents, deer, snakes, and many more animals which regulates the ecosystem.

Similarly, if a black bear is nearby, it is best to move and give the bear space or scare it off by making loud noises and looking as big as possible. Additionally, according to the Michigan Department of Natural Resources (MIDNR), people should follow the S.M.A.R.T. guidelines with black bears:

  • Stand your ground
  • Make loud noises
    • Always provide a clear escape route for the bear
    • Rarely do bears attack, but fight back if they do
    • Treat bears with respect and observe from a distance.
A black bear with several cubs. Photo by Thomas Wiensch

Black bears are the only bear species that reside in Michigan and only roam in hardwood and conifer forests. Overall, they tend to avoid humans like most animals, but it is best to take caution. Like snakes, bears also appear in the warmer months due to hibernation during cooler months. Bears also play an important role in the environment; like coyotes, bears help maintain the population of their prey including deer, elk, insects, and plants. Uniquely, because bears eat lots of berries, their scat turns into the perfect fertilizer for plants and bushes!

Any direct encounter with these animals are pretty rare. Keep in mind that biting insects such as ticks and mosquitoes pose a more serious threat when out and about this summer. Take common sense precautions with long pants, long sleeves, and repellant while enjoying any lucky wildlife sightings.

It is so important to maintain healthy relationships our wildlife because each animal helps maintain balance in the ecosystem. You can report wildlife sightings to the MIDNR using the Eyes in the Field website, where you can select a category and report your observation. And you can help protect natural areas for all of Michigan’s many species by supporting the Michigan Nature Association.