Periodical Cicadas Research Articles

Predation-driven geographical isolation of broods in periodical cicadas

Periodical cicadas are remarkable for their incredibly long, prime-numbered life cycles and almost perfectly synchronized mass emergence. Synchronized emergence is a generally localized event, referred to as a “brood”. Broods are separated in space and time, or parapatric; adjacent broods emerge on different schedules, whereas some cicadas emerge off schedule, called stragglers. Straggling can potentially erode brood boundaries; thus, the mechanism allowing broods to maintain nonoverlapping distributions is highly puzzling. Here, we propose that predation may allow broods to exclude each other. Our model and numerical simulations show that predation could act as an important factor for maintaining the nonoverlapping distributions. The proposed mechanism is most effective in the vicinity of the critical strength of predation, beyond which the population is doomed to extinction. An increase in predation intensity increases resistance to settlement of a minority brood, while suppressing the main brood population.

Technology and Interspecies Musical Practice

This case study on the work of interspecies musician David Rothenberg explores how engaging with the songs and rhythms of other species continues to challenge his musical practice and aesthetic. Technology, science and art come together in an artistic and research practice, which is grounded in the belief that technologies can bring us closer to nature. The article outlines how Umwelt theory, enactive music cognition, biosemiotics and the phenomenology of human-technology relations are engaged in the perception and creation of musical experiences. It also looks at how interdisciplinary research practices that traverse zoomusicology, the visual and performing arts, and data visualisation contribute to interspecies music theory and practice. The article concludes by presenting four interspecies auditory dispositives as a guide to how knowledge, tools and practice are entangled in concrete examples from Rothenberg’s musical collaborations with nightingales, humpback whales, periodical cicadas and pond life.

Dietary flexibility of insectivorous bats, Eptesicus fuscus and Myotis lucifugus, during Magicicada spp. Brood X emergence

Emergence of periodical cicadas, Magicicada spp. Davis, 1925, presents an ideal opportunity to study dietary flexibility and selective feeding behavior of bats. It is known that a wide array of taxa prey upon Magicicada spp., but few bat species have been documented to consume them. When larger than typical prey items, such as periodical cicadas, become abundant for a short time frame, insectivorous bats may exhibit alteration in dietary selection that provides insight into capacity and conditions for feeding. Evidence of Magicicada spp. consumption was detected in guano via polymerase chain reaction (PCR) and physical detection in both Eptesicus fuscus (Palisot de Beauvois, 1796) and Myotis lucifugus (Le Conte, 1831), two bat species of different sizes and with different dietary profiles. The consumption of these larger prey items, when they are locally abundant, supports a display of opportunistic behavior and diet flexibility in these two bat species.

Activity responses of a mammal community to a 17-year cicada emergence event

Abstract During a limited period in the summer of 2021, 17-year cicada species (Magicicada cassini, M. septendecula, M. septendecim) represented a large pulse of easily accessible food unique to forest ecosystems in the eastern United States. Using trail cameras and acoustic recorders, we tested whether the activity levels of 8 mammal species in northwestern Indiana shifted in response to spatial and temporal variation in cicada densities from 18 May to 20 June 2021. Cicada densities varied temporally and spatially across all study sites. Most mammal species with sufficient data showed no response to cicada emergence, including 2 tree squirrel species, Peromyscus mice, Eastern Chipmunks (Tamias striatus), and 2 species of bats. Raccoons (Procyon lotor), likely cicada predators, showed a quadratic or more complex activity response to cicada abundance, indicating a potential saturation point at densities near 1 cicada per m2. Surprisingly, White-tailed Deer (Odocoileus virginianus) activity decreased to almost 0 at the same cicada densities when we expected no change in activity. While size or accessibility may exclude cicadas as prey for small and volant mammals, our results suggest predation and satiation by Raccoons. In contrast, deer may be avoiding areas of cicada abundance due to other stimuli, such as high noise output, which may decrease their ability to detect predators.

Can periodical cicadas contribute to urban greening?

The potential fertilization effect of the decomposition of periodical cicadas on plant growth has been often discussed, but little quantified. I demonstrated this effect in an urban context by examining the effect of decomposing cicada carcasses and commercial lawn fertilizer on the growth of lawn grass in an 80-day greenhouse experiment. Deposition of cicada carcasses benefited aboveground growth of several lawn grasses in a dose-dependent manner, as did lawn fertilizer addition. The effect of cicadas at high levels of deposition was similar to that of the application of lawn fertilizer at half recommended rates. Notable increases in plant height and greenness were also observed in grasses given either treatment indicating the decomposition of cicadas can benefit growth in ways similar to lawn fertilizer, at least during the season following emergence.

The complete genome sequences of two species of seventeen-year cicadas: Magicicada septendecim and Magicicada septendecula.

The genus Magicicada (Hemiptera: Cicadidae) includes the periodical cicadas of Eastern North America. Spending the majority of their long lives underground, the adult cicadas emerge every 13 or 17 years to spend 4-6 weeks as adult to mate. We present the whole genome sequences of two species of 17-year cicadas, Magicicada septendecim and Magicicada septendecula. The reads were assembled by a de novo method followed by alignments to related species. Annotation was performed by GeneMark-ES. The raw and assembled data is available via NCBI Short Read Archive and Assembly databases.

The effect of sex and mating opportunity on ecological immunity in Brood X cicadas

Seventeen-year periodical cicadas represent an extreme life history, with individuals spending 17 years as juveniles and less than 45 days as adults. The implications of this life history on investment in immunity are unknown. Using monofilament implants, we examined sex differences in melanization and encapsulation-based immunity in Brood X Magicicada septendecim and M. cassini periodical cicadas. In many insects, females devote more effort to immunity than males which allows females additional time to lay eggs before death. In 17-year cicadas, the functional difference in lifespan between males and females is trivial as compared to their total lifespan. However, we found that in both species, adult females had better immunity (encapsulation response) than males. In both species, male immunity (melanization and encapsulation) declined as they aged, as did female encapsulation. However, female immunity (melanization) either did not decline or improved with age. We conclude that although male immunosenescence resembles that of shorter-lived insects, for females, melanization-based immunity is preserved as they age, potentially due to their unique life history. We also examined whether being housed in mixed-sex versus single-sex enclosures affected immunity but did not find an effect of reproductive opportunity on either melanization or encapsulation in males or females of either species. This is the first study to assay melanization or encapsulation in a cicada, so our results provide a first look at sex- and age-based immunity in this group.

How do cicadas emerge together? Thermophysical aspects of their collective decision-making.

Periodical cicadas exhibit life cycles with durations of 13 or 17 years, and it is now accepted that large prime cycles arose to avoid synchrony with predators. Less well explored is how, in the face of intrinsic biological and environmental noise, insects within a brood emerge together in large successive swarms from underground during springtime warming. Here, we consider the decision-making process of underground cicadas experiencing random, spatially correlated thermal microclimates such as those in nature. Introducing short-range communication between insects leads to an Ising model of consensus building with a quenched, spatially correlated random magnetic field and annealed site dilution, which displays the kinds of collective swarms seen in nature. These results highlight the need for fieldwork to quantify the spatial fluctuations in thermal microclimates and their relationship to the spatiotemporal dynamics of swarm emergence.

Variation in Avian Predation Pressure as a Driver for the Diversification of Periodical Cicada Broods.

AbstractPeriodical cicadas live 13 or 17 years underground as nymphs, then emerge in synchrony as adults to reproduce. Developmentally synchronized populations called broods rarely coexist, with one dominant brood locally excluding those that emerge in off years. Twelve modern 17-year cicada broods are believed to have descended from only three ancestral broods following the last glaciation. The mechanisms by which these daughter broods overcame exclusion by the ancestral brood to synchronously emerge in a different year, however, are elusive. Here, we demonstrate that temporal variation in the population density of generalist predators can allow intermittent opportunities for new broods to invade, even though a single brood remains dominant most of the time. We show that this mechanism is consistent, in terms of the type and frequency of brood replacements, with the distribution of periodical cicada broods throughout North America today. Although we investigate one particularly charismatic case study, the mechanisms involved (competitive exclusion, Allee effects, trait variation, predation, and temporal variability) are ubiquitous and could contribute to patterns of species diversity in a range of systems.

Chromosome-Level Genome Assembly and Annotation of a Periodical Cicada Species: Magicicada septendecula.

We present a high-quality assembly and annotation of the periodical cicada species, Magicicada septendecula (Hemiptera: Auchenorrhyncha: Cicadidae). Periodical cicadas have a significant ecological impact, serving as a food source for many mammals, reptiles, and birds. Magicicada are well known for their massive emergences of 1 to 3 species that appear in different locations in the eastern United States nearly every year. These year classes ("broods") emerge dependably every 13 or 17 yr in a given location. Recently, it has become clear that 4-yr early or late emergences of a sizeable portion of a population are an important part of the history of brood formation; however, the biological mechanisms by which they track the passage of time remain a mystery. Using PacBio HiFi reads in conjunction with Hi-C proximity ligation data, we have assembled and annotated the first whole genome for a periodical cicada, an important resource for future phylogenetic and comparative genomic analysis. This also represents the first quality genome assembly and annotation for the Hemipteran superfamily Cicadoidea. With a scaffold N50 of 518.9 Mb and a complete BUSCO score of 96.7%, we are confident that this assembly will serve as a vital resource toward uncovering the genomic basis of periodical cicadas' long, synchronized life cycles and will provide a robust framework for further investigations into these insects.

The forest, the cicadas and the holey fluxes: Periodical cicada impacts on soil respiration depends on tree mycorrhizal type.

The emergence of billions of periodical cicadas affects plant and animal communities profoundly, yet little is known about cicada impacts on soil carbon fluxes. We investigated the effects of Brood X cicadas (Magicicada septendecim, M. cassinii and M. septendeculain) on soil CO2 fluxes (RS ) in three Indiana forests. We hypothesized RS would be sensitive to emergence hole density, with the greatest effects occurring in soils with the lowest ambient fluxes. In support of our hypothesis, RS increased with increasing hole density and greater effects were observed near AM-associating trees (which expressed lower ambient fluxes) than near EcM-associating trees. Additionally, RS from emergence holes increased the temperature sensitivity (Q10 ) of RS by 13%, elevating the Q10 of ecosystem respiration. Brood X cicadas increased annual RS by ca. 2.5%, translating to an additional 717 Gg of CO2 across forested areas. As such, periodical cicadas can have substantial effects on soil processes and biogeochemistry.

Stability and optimal control for an age-structured model of periodical cicadas

Stability and optimal control for an age-structured model of periodical cicadas

Periodical Cicadas and the Abundance of Time

The life cycle of periodical cicadas, like the scientists who have studied them, is characterized by periods of long waiting punctuated with spectacular bouts of activity. In remarkable synchrony, every thirteen or seventeen years—depending on the species and the locatio —billions of nymphs crawl from the ground and embark on a relatively short adult life span of three to four weeks. This paper traces three pulses in the scientific study of periodical cicadas, as researchers sought to determine the geographical range of the broods, the number and biological identity of the species found in each brood, and the relationship between the individual and the swarm. Together these threads of research highlight the historical significance of mass collaboration in the scientific study of these charismatic animals and the surprisingly entangled affective relations between human and insect.

Long-term monitoring and analysis of Brood X cicada activity by distributed fiber optic sensing technology.

Brood X is the largest of the 15 broods of periodical cicadas, and individuals from this brood emerged across the Eastern United States in spring 2021. Using distributed acoustic sensing (DAS) technology, the activity of Brood X cicadas was monitored in their natural environment in Princeton, NJ. Critical information regarding their acoustic signatures and activity level is collected and analyzed using standard outdoor-grade telecommunication fiber cables. We believe these results have the potential to be a quantitative baseline for regional Brood X activity and pave the way for more detailed monitoring of insect populations to combat global insect decline. We also show that it is possible to transform readily available fiber optic networks into environmental sensors with no additional installation costs. To our knowledge, this is the first reported use case of a distributed fiber optic sensing system for entomological sciences and environmental studies.

Periodical cicadas disrupt trophic dynamics through community-level shifts in avian foraging.

Once every 13 or 17 years within eastern North American deciduous forests, billions of periodical cicadas concurrently emerge from the soil and briefly satiate a diverse array of naive consumers, offering a rare opportunity to assess the cascading impacts of an ecosystem-wide resource pulse on a complex food web. We quantified the effects of the 2021 Brood X emergence and report that more than 80 bird species opportunistically switched their foraging to include cicadas, releasing herbivorous insects from predation and essentially doubling both caterpillar densities and accumulated herbivory levels on host oak trees. These short-lived but massive emergence events help us to understand how resource pulses can rewire interaction webs and disrupt energy flows in ecosystems, with potentially long-lasting effects.

Periodical cicadas (Magicicada spp.): Predator satiation, or too much of a good thing?

Periodical cicadas (Magicicada spp.): Predator satiation, or too much of a good thing?

Do adult Magicicada (Hemiptera: Cicadidae) feed? Historical perspectives and evidence from molecular gut content analysis.

The periodical cicadas in the genus Magicicada are remarkable for their unusual life histories and dramatic synchronized emergences every 13 or 17 years. While aspects of their evolution, mating behaviors, and general biology have been well-characterized, there is surprising uncertainty surrounding the feeding habits of the short-lived adult stage. Despite a tentative scientific consensus to the contrary, the perception that adult Magicicada do not feed has persisted among the general public, and recent studies are lacking. We directly investigated the feeding behavior of Magicicada spp. through high-throughput sequencing (HTS)-based dietary analysis of nymphs, freshly molted (teneral) adults, and fully sclerotized adults collected from orchard and wooded habitats during the 2021 emergence of Brood X. Identifiable plant DNA (trnF, ITS amplicons) was successfully recovered from nymphs and adults. No plant DNA was recovered from teneral adults, suggesting that all DNA recovered from sclerotized adults was ingested during the post-teneral adult stage. Both nymphs and adults were found to have ingested a range of woody and herbaceous plants across 17 genera and 14 families. Significantly more plant genera per individual were recovered from adults than from nymphs, likely reflecting the greater mobility of the adult stage. We hypothesize that the demonstrated ingestion of plant sap by Magicicada adults is driven by a need to replace lost water and support specialized bacteriome-dwelling endosymbionts that cicadas depend upon for growth and development, which constitutes true feeding behavior.

Use of tree species by three species of Magicicada (Hemiptera: Cicadidae) in an Appalachian forest

Periodical cicadas (Magicicada spp.) are endemic to deciduous forests in the eastern United States. In successional forests, they must partition resources such as host trees to coexist. We measured tree size, emergence holes, oviposition scar bundles, and chorusing center abundances of Magicicada species on 12 common tree species in a deciduous forest to understand host-tree use. We predicted that the abundance of periodical cicadas and use of specific host-tree species would change depending on the Magicicada species and tree life stage. We considered the size of the tree (diameter at breast height) as a covariate to control for tree size and collected eggs for a greenhouse experiment to assess whether nymphs prefer to feed on Quercus rubra or Acer saccharum. More emergence holes were found below Quercus species than any other tree species. The abundance of periodical cicadas on host trees used for chorusing centers varied depending on the Magicicada species, but were most abundant on Quercus species. Oviposition scar bundles were also more frequent on Quercus. More nymphs were found on Quercus than Acer in the nymph preference study. Though periodical cicadas used Quercus hosts more than other tree species, their abundances on different host tree sizes and species differed significantly. Periodical cicada species may use specific host species and life stages as a way to partition resources and minimize competition among the Magicicada species during emergence years.

Periodical Cicada Emergences Affect Masting Behavior of Oaks.

AbstractOaks (Quercus spp.) are masting species exhibiting highly variable and synchronized acorn production. We investigated the hypothesis that periodical cicadas (Magicada spp.), well known to have strong effects on the ecosystems in which they occur, affect acorn production of oaks through their xylem feeding habits as nymphs, the oviposition damage they inflict as adults during emergences, or the nutrient pulse resulting from the decomposition of their bodies following breeding. We found negative effects on acorn production during emergence years and the year following emergences and enhanced acorn production 2 years after emergence. We also found evidence indicating a significant effect of cicada emergences on spatial synchrony of acorn production by trees growing within the range of the same cicada brood compared with different broods. These results demonstrate that periodical cicadas act as a trophic environmental "veto" depressing acorn production during and immediately following emergences, after which the nutrient pulse associated with the cicada's demise enhances oak reproduction.

The 2021 emergence of Brood X periodical cicadas Magicicada spp. (Hemiptera: Cicadidae) in Georgia, United States of America

The US state of Georgia includes the range of several periodical cicada broods and is the southernmost state in which Brood X periodical cicadas emerge; however, no research has focused on this brood in this state. We used reports of sightings on social media, communication with the public, and our own searches to determine the geographic range in Georgia and timing of biological events. Both adults and exuviae were identified to species to determine the species makeup at those locations. The first Brood X adult was photographed on April 26 in Lumpkin County, and Magicicada septendecim L. was the most common species. Online records and site visits led to distribution records in nine counties, including six that provided no records in the 2004 emergence. Driving surveys revealed patchy distributions of chorusing adults and species distribution modeling further predicted locations where Brood X can be found in future surveys. We observed cicada oviposition scars at two locations and found no effect of host plant on presence or density of scars. Lastly, collections of dead adults showed female remains were less common and more likely to be dismembered. Further investigations of the periodical cicadas in Georgia are recommended to better understand the phenology, evolution, and ecology of these remarkable insects.