Most cicadas need air temperatures of at least 22 to 25°C (roughly the low-to-mid 70s°F) before they will sing at all, and their songs grow louder and faster as the mercury climbs from there. The precise threshold shifts from species to species, but the underlying reason is consistent: the muscles that produce a cicada’s call are temperature-sensitive, and they simply cannot fire fast enough in cool air. That relationship between heat and song runs deeper than a simple on-off switch, shaping everything from the rhythm of individual calls to the time of day entire populations choose to chorus.
Why the Singing Muscles Need Warmth
A male cicada sings by rapidly buckling a pair of ribbed membranes called timbals on the sides of its abdomen. Each buckling-and-recovery cycle produces a click, and hundreds of clicks per second fuse into the buzzing drone you hear from a treetop. The speed of that cycle depends almost entirely on how warm the timbal muscles are. In laboratory studies, the twitch rise time of timbal muscles drops and tension production climbs as muscle temperature increases, with performance improving all the way up to about 40°C. The muscles must be elevated well above cool resting temperatures before a cicada can produce a normal calling song at all.1PubMed. Timbal muscle physiology in the endothermic cicada Tibicen winnemanna (Homoptera: Cicadidae)
This is not a subtle effect. When researchers raised chamber temperatures around three European cicada species, syllable rates increased by 44 to 75 percent at the highest temperatures compared to the lowest. The timbal apparatus also recovered from each deformation faster in warmer conditions, which is what allows the click rate to climb.2Journal of Comparative Physiology A. Temperature dependence of cicada songs (Homoptera, Cicadoidea) In practical terms, if you could slow-motion film a cicada’s timbal at 25°C and again at 35°C, the warmer insect would be buckling its membranes dramatically faster, and the resulting song would sound higher-pitched and more continuous.
The Minimum Temperature to Start Calling
Among the best-documented thresholds, three species of European Tibicina cicadas require a minimum ambient temperature of 22 to 24°C before they will call. Below that range, males sit silent even in broad daylight. Once air temperature crosses that threshold, calling begins, and sound power rises in step with further warming.3Physiological Entomology. Ambient temperature and sound power of cicada calling songs (Hemiptera: Cicadidae: Tibicina) The songs do not just switch on at a fixed volume; they ramp up. A cicada calling at 28°C is measurably quieter than the same individual calling at 34°C.
That 22 to 24°C minimum is not a universal rule for all cicadas, though. Different species have carved out their own thermal comfort zones. Research on Mediterranean cicada communities found that fitness-relevant activities, including singing, are fine-tuned to a species-specific temperature optimum, and that these different optima help coexisting species partition the same habitat without drowning each other out.4Wiley Online Library (Physiological Entomology). Ecophysiological responses to climate change in cicadas One species might peak at midday heat while another calls most actively in the cooler morning or late afternoon. Temperature is, in a sense, a scheduling tool that prevents acoustic chaos.
How Songs Change as Temperatures Rise
Once a cicada is warm enough to sing, further heating changes the character of the song, not just its volume. The syllable rate speeds up, individual syllables shorten, and the overall pulse pattern becomes more compressed. In the three species tested in controlled warming experiments, the fastest syllable rates were recorded at the highest chamber temperatures, with increases of 45 to 84 extra syllables per second depending on the species.2Journal of Comparative Physiology A. Temperature dependence of cicada songs (Homoptera, Cicadoidea) For anyone who has noticed that the summer buzz sounds somehow more frantic on the hottest afternoons, this is the reason.
The relationship between temperature and sound power follows the same upward curve. Louder songs travel farther, which means males calling in peak heat reach more potential mates than males calling in marginal warmth. This creates a strong incentive to sing at the hottest part of the day, as long as the heat does not become lethal.3Physiological Entomology. Ambient temperature and sound power of cicada calling songs (Hemiptera: Cicadidae: Tibicina)
That said, the link between body temperature and specific call parameters is not always tight at the individual level. In the common European cicada Cicada orni, field recordings showed that while body temperature was behaviorally regulated to the range needed for calling, the variation in call parameters between different individuals was greater than the variation caused by temperature shifts within one individual. The population sounds warmer on a hot day because more males are singing and singing louder, but each male’s personal call signature may not shift as dramatically as the overall chorus suggests.5European Journal of Entomology. Thermoregulation and the influence of body temperature on calling song parameters in Cicada orni (Hemiptera: Cicadidae)
Cicadas That Generate Their Own Heat
Most cicadas are ectotherms: they rely on the sun and surrounding air to warm their flight muscles and timbal muscles to working temperature. But a handful of species cheat. Certain African platypleurine cicadas are endothermic, meaning they generate body heat internally before and during singing. Field measurements show these animals actively regulate their body temperature through endogenous heat production, and researchers have observed a unique warm-up behavior in which the abdomen pulses in a telescoping rhythm as the insect raises its internal temperature.6PubMed. Hot-blooded singers: endothermy facilitates crepuscular signaling in African platypleurine cicadas (Hemiptera: Cicadidae: Platypleura spp.)
This ability to self-heat opens up a time slot that ectothermic cicadas cannot use: dusk and dawn, when ambient temperatures have dropped below the threshold most species require. By warming their own muscles, crepuscular (twilight-active) cicadas can call when the acoustic landscape is quieter and competition for a mate’s attention is lower. It is an energetically expensive strategy, but the payoff is a near-monopoly on the evening soundscape.
Endothermy in cicadas mirrors what some large moths and bees do with their flight muscles, and it underlines just how powerful the link between temperature and singing is. If ambient heat were merely convenient rather than essential, no cicada would waste metabolic energy manufacturing its own. The fact that some lineages evolved internal heating specifically to extend their calling window tells you that temperature is the gating factor for cicada song.
Surviving the Heat at the Other Extreme
If warmth is so beneficial for singing, you might expect cicadas to thrive endlessly in scorching deserts. Some do, but they face the opposite problem: overheating. The desert cicada Diceroprocta apache, found in the American Southwest, routinely calls in ambient temperatures above 40°C. To avoid cooking, it uses an evaporative cooling system that would be the envy of any engineer. While feeding on plant xylem sap, the cicada pushes water through pores on its thorax and abdomen, and the evaporation of that water can hold its body temperature as much as 5°C below the surrounding air temperature when the air reaches 42°C.7Journal of Experimental Biology. Evaporative Cooling in the Desert Cicada: Thermal Efficiency and Water/Metabolic Costs
The cooling kicks in at a remarkably precise trigger point. Detailed measurements of cuticular water loss show that active water extrusion begins at 39.2 to 39.3°C in both males and females. Below that point, the cuticle is relatively waterproof. Above it, water floods the surface in irregular bursts from specialized large pores on the back and abdomen.8Journal of Experimental Biology. Regional Differences in Cuticular Permeability in the Desert Cicada Diceroprocta Apache: Implications for Evaporative Cooling If the cicada runs low on sap or the heat becomes too extreme for evaporative cooling to keep pace, it must stop singing and retreat to a cooler microclimate. The lethal body temperature is not far above the activation threshold, so the margin for error is thin.
The desert cicada’s strategy neatly illustrates the thermal corridor cicadas operate in. Below roughly 22 to 25°C, the muscles cannot fire fast enough to produce a proper song. Above about 40 to 42°C, the body overheats unless active cooling is possible. The singing window is the range in between, and different species have evolved different ways to stretch it at one end or the other.
Behavioral Thermoregulation and Daily Timing
Even species that cannot generate internal heat or sweat through their cuticle still manage their body temperature carefully. Behavioral thermoregulation, a phrase that really just means picking the right spot to sit, is widespread in cicadas. Males position themselves in sun or shade, orient their bodies to absorb or deflect solar radiation, and shift perching height on tree trunks over the course of a day. Studies on Cicada orni confirmed that individuals actively regulate body temperature through these behavioral mechanisms, keeping themselves within the range needed for calling.5European Journal of Entomology. Thermoregulation and the influence of body temperature on calling song parameters in Cicada orni (Hemiptera: Cicadidae) Tibicina species have been observed to do the same.3Physiological Entomology. Ambient temperature and sound power of cicada calling songs (Hemiptera: Cicadidae: Tibicina)
This explains the daily rhythm many people notice: silence in the cool morning, a rising chorus through late morning as the sun heats the canopy, peak volume in the early-to-mid afternoon, and a gradual tapering as evening temperatures fall. On overcast or unusually cool days, the chorus may be thin or absent entirely, even during midsummer. If you have ever noticed that a cloudy summer afternoon feels eerily quiet compared to a sunny one at the same calendar date, that is almost certainly a temperature effect on the local cicada population. The insects are still there; their muscles are just too cool to perform.
In tropical and subtropical regions where nighttime temperatures stay above the calling threshold, some species sing well after dark. Temperate-zone cicadas, by contrast, almost always fall silent once the sun goes down, because air temperatures drop below the minimum they need. The exceptions tend to be urban areas, where pavement and buildings retain heat and may keep local air temperatures a few degrees above surrounding countryside well into the night.
Species Stacking and Acoustic Partitioning
When multiple cicada species share the same habitat, they often sort themselves by temperature preference in a way that prevents their songs from overlapping too badly. One species might call only above 30°C, peaking at midday, while a second calls at 24 to 28°C and dominates the morning chorus. A third might be an endothermic dusk specialist. The result is a shifting acoustic landscape where different voices fade in and out as temperature rises and falls through the day. This temperature-driven partitioning is well documented in Mediterranean cicada communities, where species-specific thermal optima help explain which species calls when.4Wiley Online Library (Physiological Entomology). Ecophysiological responses to climate change in cicadas
Climate change adds a wrinkle to this system. As average temperatures rise, the windows shift. A species that previously dominated a particular time slot may find its optimal window expanding, potentially overlapping with a neighbor’s. Or a species near the upper end of its thermal tolerance may find that peak afternoon temperatures now push past the comfort zone, compressing its calling time. Researchers have flagged this as a concern for cicada diversity in warming climates, since the acoustic partitioning that keeps species reproductively isolated depends on those temperature windows staying relatively stable.
What Periodical Cicadas Need
If you live in eastern North America, the cicadas you are most likely to notice are the periodical species, the ones that emerge in enormous synchronized broods every 13 or 17 years. These Magicicada species follow the same general temperature rules. Males do not start chorusing until conditions are warm enough, and during a cool, rainy emergence week the timing can be noticeably delayed compared to a warm one. Because periodical cicadas emerge in spring rather than midsummer, they encounter a wider range of daily temperatures than most annual cicadas do, and their calling activity tracks the sun closely. A warm afternoon in late May can produce deafening choruses, while a cool morning the following day leaves the same trees quiet.
Periodical cicadas tend to call at somewhat lower ambient temperatures than many tropical or desert species, which makes sense given their spring-emergence lifestyle. But the muscle physiology is the same: warmth speeds the timbal, cold slows it. If you are hoping to experience one of those legendary mass choruses, pick a sunny afternoon when temperatures are well into the 20s°C (upper 70s to 80s°F). A drizzly 15°C day will be a disappointment.
How Hydration Intersects with Temperature
Temperature is the primary driver of cicada song, but water availability plays a supporting role that is easy to overlook. The desert cicada’s evaporative cooling system depends entirely on access to xylem sap. If the host plant is drought-stressed and sap pressure drops, the cicada loses its coolant supply and must stop singing or risk lethal overheating. The extent and duration of evaporative cooling depend on the cicada’s hydration state and the rate of water flux through its cuticular pores.7Journal of Experimental Biology. Evaporative Cooling in the Desert Cicada: Thermal Efficiency and Water/Metabolic Costs
Even in non-desert species, xylem feeding is the norm, and a well-hydrated cicada can afford to sit in direct sun longer, which keeps its muscles warmer and its song stronger. Drought conditions can reduce chorus intensity even when temperatures are favorable, because males must spend more time feeding and less time calling, or because dehydrated individuals retreat to shade sooner. The interaction between heat and water helps explain why the loudest cicada summers tend to be both warm and at least moderately wet. A baking-hot drought may actually suppress calling in some habitats, even though temperature alone would seem ideal.
Practical Observations for Listeners
If you want to predict when cicadas will be singing in your area, a cheap outdoor thermometer is surprisingly useful. As a rough guide across common North American and European species, expect silence below about 21 to 22°C and increasing volume above 25°C. Peak intensity usually coincides with the hottest part of the afternoon, between roughly 1:00 and 4:00 p.m. On days that stay below the threshold, even during the active season, the silence can be startling.
Wind matters too, not because it changes the temperature directly but because it cools the cicada’s body by convection, effectively lowering its muscle temperature even when air temperature is adequate. A breezy 26°C day may produce less singing than a still 24°C day, which can be confusing if you are watching a thermometer alone. The animal’s body temperature, not the weather station’s reading, is what counts, and wind widens the gap between the two.
Altitude and microclimate also shift the picture. Cicadas on a sun-baked south-facing wall can be calling vigorously while a population in nearby forest shade stays quiet, even though both locations would register a similar air temperature on a weather map. The insect is responding to its immediate thermal environment: the sun hitting its body, the radiated heat from bark or stone, and the local air flow around its perch. Understanding this helps explain why one backyard can roar with cicadas while another a block away is relatively calm.