Learn About The Amazing, Strange, and Unusual Synchronous Fireflies

Fireflies are truly one of the most fascinating creatures. Although they attack humans when aggressive, they are sometimes good too. There are multiple species of fireflies and one of the oddest ones are the Synchronous Fireflies. Due to their unique properties and particular ways of synchronizing, many people are surprised when they see these fireflies. Learn more about them below. 

What are Synchronous Fireflies?

Synchronous fireflies are one of the species of fireflies that have some unique synchronous characteristics. The flashing sequence between the male and female fireflies is quite fascinating. Each of these species has a specific pattern of flashing which helps the male identify the female and vice versa. It clearly shows that these fireflies are communicating in the form of synchronous light and this is what has surprised many scientists as well as tourists too. Synchronous fireflies produce a yellowish-green light while many others may have a blue or white light as well. 

The main difference between male and female synchronous fireflies is that males flash while flying while females flash when stationary, but only as a response to the males. Each year, these fireflies come up with a display of flashing to find their mate with their significant others synchronizing the flashing light patterns. 

Animated display of fireflies with a girl.

Description of Synchronous Fireflies

Synchronous Fireflies are rare but one can still find them in America. For those who don’t know why these fireflies flash, it is because of a phenomenon known as bioluminescence. As a matter of fact, fireflies are not the only creatures that produce light and there are many others as well such as jellyfish, glowworm beetles, and different types of fungi. 

Species like fireflies flash because there is a series of chemical reactions resulting in the emission of low or no heat. When luciferin, a chemical emitted from fireflies, combines with oxygen and the enzyme luciferase, light is produced in the back part of a firefly. This is considered a cold light. 

Forest having fireflies. 

One of the distinct features of a synchronous firefly is that males fly single and not in the form of groups up until a female firefly responds in the same flashing signal. As far as the timing of this flashing is concerned, it is just about 2 to 4 seconds for a male. After that, there is absolute darkness for the next 8 to 12 seconds. Within this time period, a female replies with a less bright flash along with a pulsed signal. According to biological experts, one reason why the dark period occurs is that the males are searching for the appropriate female responses without getting distracted from other males. 

Another reason is that sometimes the synchronous proposition of light may end because the body is not producing enough chemical reaction for a consistent and longer period of flashing pattern. Therefore, the flashing stops for some time. 

The Behavior of Synchronous Fireflies

What has surprised scientists for many years is the fact that these fireflies possess an immense intelligent quotient. With their flashing and choosing a partner, it shows that their DNA has some sort of decision-making instinct allowing them to choose the right partner for themselves. As a matter of fact, when females are choosing their mate, they don’t just choose the first one rather they evaluate the behavior of many males along with their flashing patterns before making the decision. The “ignorance” towards the first few males is quite apparent. What’s strange about it all is the fact that this shows quite human behavior. 

Besides, another unusual behavior of the synchronous fireflies is that during the early stages of mating and copulation, males try to separate the couple. The males try to separate the couple so that they can mate with the females. Sometimes, the males may be able to fulfill this separation and the mating process starts again. However, if the couple sticks together during stage 1 copulation and moves toward stage 2 copulation, the other unmated males fly away. They then search for new female partners. 

Hover here to find out more fun facts about fireflies – Fun Facts About Fireflies.

Animated display of fireflies.

The Display of Synchronous Fireflies

One of the best things about this entire scenario is the scenic view that begins when the males and females start to flash their lights. The little population of these fireflies can be found at Great Smoky Mountains National Park in Tennessee and North Carolina. Over the years, this place has become a great tourist spot for all nature lovers, and particularly firefly enthusiasts who want to see this display of nature. It is important to know that the mating display happens between May and June which makes it quite a rare sight. 

During the mating season, people come around on a trail in the Great Smoky Mountains National Park where males and females are flashing lights to find their perfect mate. To make it even better for the people, biological experts and scientists use a degree-day model which helps in evaluating the dates of “peak display”. This becomes truly one of the rarest and most spectacular sights for anyone to see. 

On the official website of Great Smoky Mountains National Park, you can find out different types of rules and regulations associated with watching the display of synchronous fireflies. Besides, the time schedules, lottery applications, and other guidelines regarding synchronous fireflies are also mentioned over there.

Display of synchronous fireflies in Pennsylvania, 2013

Planning Your Trip to View The Synchronous Fireflies

By now, many of you might be tempted to view this astonishing display of synchronous fireflies. However, getting into the Great Smoky Mountains National Park is not going to be easy particularly in the mating seasons. Visitors can be allowed vehicle parking confirmation or denied the vehicle parking confirmation depending upon the demand, first-come-first-serve, and other few parameters as well. If you are a “would-be ” visitor, you will have to park at Sugarlands visitor from where a trolley will take you to the viewing spot. 

Make sure that you don’t litter the park or destroy the natural habitat of these creatures. It is best to visit this during the weekdays instead of weekends. This is because, over the weekends, there can be as much as a 4-hour wait before any proper conveyance is arranged for the people. Besides, sometimes, it is so rushy on the weekend that a person may not be able to enjoy it fully. With increasing crowds, there are certain red flags raised as well which is why the park management has decided to implement a set of even strict policies.

One should plan their trip in accordance with the schedule provided by the management of the park. Keep your dates flexible because there can be any unforeseen events that could disrupt your visit. For example, the synchronous fireflies do not mate in the rainy season, or in other cases, if the temperature drops below 50 degrees Fahrenheit, the fireflies will not mate meaning that there will be no display by these fireflies. 

Be Careful With These Things

Certain things should be kept in mind before going to watch the fireflies. One of the main mistakes that many people make is that they use their phone’s flashlights to view the fireflies. Not only does this disrupt their mating but it also blocks your or others’ view. Keep in mind that the darker it is, the more easily you will be able to spot these fireflies and enjoy the spectacular view. 

Since it is dark at the Great Smoky Mountain Park, many people have to use flashlights for walking to the viewing spot. It is important to use a flashlight with a red filter or with red cellophane so that neither does it impact the eyes of others or affect the fireflies. Moreover, your flashlight must be pointed on the ground so you and others can see the walking area well. Once you do find the viewing spot, turn off the flashlight and enjoy the view. 

Keep the area clean and do not attempt to catch the fireflies. During their mating season, some of them can be wild as well. It is best to carry a bag along with you so you can keep all the garbage in it. 

Find out more about national parks of US here – Interesting Facts about USA National Parks


Synchronous fireflies are one of the most fascinating creatures on our planet. The unexplainable phenomenon of simultaneous flashing has surprised many scientists and tourists. Even today, many questions remain unanswered as long as the synchronous fireflies are concerned. We recommend that you have at least one trip to view these amazing creatures. If you are interested in learning about other strange creations in the world, read our article on Amazing, Strange, and Unusual Blue Animals.