Evenings in panhandle Florida produce a raucous din created by insects, amphibians and birds.
Anyone hearty enough to take an early evening walk in north Florida will experience a continuation of the frenetic activity and riotous sounds typical to summer in the south. The near deafening call of cicadas (Magicicada spp.) is part of the cacophony.
Once commonly identified as locusts in the region, their near-mechanical buzzing originates from the protection of foliage in trees and bushes during the day or twilight hours.
It is important to note cicadas are not the locust of infamy which shreds the green, lush landscapes and foretells famine. While locusts and cicadas are both insects, the similarities end there.
Local cicadas are often seen clinging to trees and branches, often obscured by leaves. At night their presence is confirmed by a chorus of loud calls for a mate.
These seldom seen or captured insects known for their boisterous, sometimes undulating, chorus do leave strategically placed souvenirs for the sharp-eyed observer. This discarded residue of their early life stages is a highly valued tool for many elementary age school children with a prank in mind.
The hard shell is harmless, but under the right conditions it does have a certain shock value appreciated by juvenile miscreants.
Their nymph stage skeletons are often seen on the trunks of trees, shrubs, stalks and even the siding of buildings. The opaque brown shells are abandoned when the cicada outgrows it and emerges to form a new exterior.
The process is similar for other insect species with an exoskeleton, as the protective shell has limited potential for growth and expansion. The rigid coating provides this creature with an armored surface to fend off the challenges of being small in a big, hungry world.
In some states further north cicadas are famous for their periodic appearance in colossal numbers, sometimes as many as 1.5 million per acre. For the first time since 1803 there is the rare emergence of both 13- and 17-year cicadas currently.
The 17-year cicada (Magicicada cassini) is emerging in states to the north. These cousins to the local species make their presence known by their tremendous numbers and near deafening nightly cacophony. By midsummer they will retreat until 2041.
These periodic swarms do not occur in Florida which has warmer weather and an environment far friendlier to the insects.
The 19 Florida cicada species fall into three groups based on overall size measured by the length of the forewings. They produce their songs with timbals, paired drum-like structures on the sides of the abdominal segments.
A muscle attached to the timbal plate causes the timbal ribs to pop inward and project outward when relaxed. Flexed rapidly, the cicada chorus can deliver hours of uninterrupted night music.
In Florida only males have timbals and the females are mute. Most sounds made by males are calling songs which serve to attract the silent females.
Cicada nymphs live in underground burrows where they feed on xylem sap from roots of grasses or woody plants. Because xylem sap is low in nutrients, complete nymph development takes several years to successfully mature.
All cicada species molt four times underground. When the cicada nymph is ready for its fifth and final molt, it makes its way to the soil’s surface. It climbs a short distance up a tree trunk or stem, anchors itself and molts for the last time, becoming an adult.
If male, the new cicada will add its contribution to the nightly festivities. If female, she will quietly wait for that special, one in a million, nocturnal crooner.
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