Field Notes


February 10, 2023

Cicadas are large insects with long and unique life cycles. These fascinating insects are found on every continent except Antarctica. Michigan hosts ten species. Living 2-17 years (depending on the species), nearly all their life is spent underground feeding on tree root sap. Their life cycle begins with hatching from eggs laid on trees and shrubs. They then migrate underground in a larval state where they turn into nymphs, and after years, they emerge for a short period above ground to molt their nymph stage exoskeleton, (which are fairly easy to spot) and become adults.

As mature insects, they are strong flyers and spend much of their time high in tree canopies, so despite hearing them regularly, they aren’t seen often. The adult stage lasts a month or two, during which time cicadas use their songs to attract a mate, breed and lay eggs for the next generation.

Late summer in Michigan wouldn’t be the same without the buzzy song of the cicada. That ubiquitous and sometimes noisy sound (cicadas make the loudest noise of any insect) is so synonymous with dog days of summer that some are actually called dog day cicadas! These species are quite common in Michigan and are known as annual cicadas. Despite a 2-5 year life cycle, annual cicadas don’t emerge in synchrony (like the 17-year periodical cicadas), so we hear and see them annually.

Enjoy the symphony!


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