Cicada Emergence Research Articles

PREDICTING EMERGENCE, CHORUSING, AND OVIPOSITION OF PERIODICAL CICADAS

Periodical cicadas in the genus Magicicada have an unusual life history that includes an exceptionally long life cycle and a massive, synchronized emergence. Distributions in woodland habitat are extremely patchy, and an unresolved problem is how the patchiness is generated and maintained. We undertook a study in Princeton, New Jersey, USA, to determine if habitat factors such as tree height, distance to the nearest neighbor, and amount of foliage influence distributions of nymphal emergences, centers of chorusing aggregations, and oviposition sites. Emerging nymphs were counted, chorus centers were identified by measuring decibel levels of their songs, and oviposition was estimated from the foliage "flags" that are produced by trees in response to the damage caused by egg-laying. All three distributions were mapped on 50 trees in a human-managed area of 75 x 130 m. We were unable to identify habitat features that were associated with the distribution of emergences, except that tulip trees (Liriodendron) had significantly fewer emergences than two other genera, ash (Fraxinus) and beech (Fagus). Using multiple linear regression analysis, we found that the distribution of emergences was the best predictor of the distribution of chorus centers and oviposition sites. In an analysis of ash trees alone, tree height and spacing, in addition to cicada emergences, predicted chorus centers and oviposition incidence. Thus the distribution of the offspring generation (oviposition) is shown to be similar to the parental generation (emergence). We suggest that their stability is maintained across generations by extremely low dispersal and mutual attraction. Aggregations may be thought of as self-perpetuating, randomly distributed assemblages, initially established through the interaction of factors, including successful exploitation of underground resources, and avoidance of fungal disease and aboveground predation in the development of high-density mating aggregations.

EFFECTS OF PERIODICAL CICADA EMERGENCES ON ABUNDANCE AND SYNCHRONY OF AVIAN POPULATIONS

We used 37 years of North American Breeding Bird Surveys to test for effects of periodical cicada (Magicicada spp.) emergences on the abundance and spatial synchrony of 24 species of avian predators in hardwood forests of the eastern United States. Fifteen (63%) of the bird species exhibited numerical changes in abundance apparently associated with emergences of the local periodical cicada brood, and intraspecific spatial synchrony of bird abundance was significantly greater between populations sharing the same cicada brood than between populations in the ranges of different broods. Species exhibited at least four partially overlapping temporal patterns. (1) Cuckoos ( Coccyzus spp.) occurred in high numbers only during emergence years and subsequently declined in abun- dance. (2) Red-bellied Woodpeckers (Melanerpes carolinus), Blue Jays (Cyanocitta cris- tata), Common Grackles (Quiscalus quiscula), and Brown-headed Cowbirds (Molothrus ater) increased significantly 1-3 years following emergences and then declined. (3) Red- headed Woodpeckers (Melanerpes erythrocephalus ), American Crows (Corvus brachyryn- chos), Tufted Titmice (Baeolophus bicolor), Gray Catbirds (Dumetella carolinensis), and Brown Thrashers (Toxostoma rufum) were found in significantly low numbers during emer- gence years, underwent significant numerical increases in the following year, and then stabilized. (4) Wood Thrushes (Hylocichla mustelina), Northern Mockingbirds (Mimus po- lyglottos), Northern Cardinals (Cardinalis cardinalis), and House Sparrows (Passer do- mesticus) exhibited significantly deviant population numbers 1-2 years prior to emergences, below the long-term mean in the first two species and above the long-term mean in the latter two. These results suggest that the pulses of resources available at 13- or 17-year intervals when periodical cicadas emerge have significant demographic effects on key avian predators, mostly during or immediately after emergences, but in some cases apparently years following emergence events.

Annual Fire, Mowing and Fertilization Effects on Two Cicada Species (Homoptera: Cicadidae) in Tallgrass Prairie

Abstract In tallgrass prairie, cicadas emerge annually, are abundant and their emergence can be an important flux of energy and nutrients. However, factors influencing the distribution and abundance of these cicadas are virtually unknown. We examined cicada emergence in plots from a long-term (13 y) experimental manipulation involving common tallgrass prairie management practices. The plots were arranged in a factorial experimental design, incorporating annual burning, mowing and fertilization (10 g N m−2 and 1 g P m−2). One cicada species, Cicadetta calliope, responded positively to fire, but negatively to mowing, and was most abundant in plots that were burned, unmowed and fertilized. Increased density of C. calliope in this treatment combination is related, in part, to increased availability of oviposition sites aboveground. Furthermore, C. calliope females from fertilized plots were significantly larger in body size relative to females from unfertilized prairie. Another cicada species, Tibicen aurifer...

Infectivity of resting spores of Massospora cicadina (Entomophthorales: Entomophthoraceae), an entomopathogenic fungus of periodical cicadas (Magicicada spp.) (Homoptera: Cicadidae).

Massospora cicadina Peck is a fungal pathogen of 13- and 17-year periodical cicadas (Magicicada spp.). In northwest Arkansas, during the spring 1998 emergence of the 13-year periodical cicada, Magicicada tredecassini (Brood XIX), <1% of emerging cicadas were infected with the conidial stage of M. cicadina, similar to data collected from the same population in 1985. However, in northwest Arkansas plots treated with M. cicadina resting spores collected from infected 17-year Magicicada septendecim cicadas (Brood IV) in 1997 from southern Iowa, 10 months prior to the 1998 emergence in Arkansas, conidial stage infections of M. cicadina in 13-year Arkansas M. tredecassini cicadas increased significantly to 10.6% (7.9% in males and 2.6% in females). These data suggest that M. cicadina resting spores do not require a dormancy of 13 or 17 years between cicada emergences. Instead M. cicadina resting spores appear to be capable of germinating and infecting periodical cicadas after less than 1 year. In addition, M. cicadina resting spores derived from one species (17-year M. septendecim cicadas) were infective for a second species (13-year M. tredecassini cicadas). A mean of 1.4 x 10(6)(SE = 1.8 x 10(5)) mature resting spores were produced per infected male M. septendecim.

Periodical Cicada (Magicicada cassini) Oviposition Damage: Visually Impressive yet Dynamically Irrelevant

Abstract Selective herbivory by animals can have significant effects on the succession of a plant community. Damage resulting from major insect outbreaks has been shown to alter species dominance and competitive balance of woody plants in temperate North America. In this study we examine the effects over three seasons of a visually striking herbivory event: periodical cicada (Magicicada cassini) oviposition into an early successional tree community in the prairie-forest ecotone in eastern Kansas. Oviposition damage during cicada emergence in 1998 was large in overall magnitude, highly variable in space and varied by host tree species. From 1998–2000 we monitored four measures of tree growth on individuals of each tree species on the study site, and infructescence production on the dominant species (rough leaved dogwood, Cornus drummondii). Cicada damage in 1998 was regressed against each measure of tree performance in following years. Only a few statistically significant results were found. Overall, we co...

Emergence of Periodical Cicadas (Magicicada cassini) From a Kansas Riparian Forest: Densities, Biomass and Nitrogen Flux

The 1998 emergence of 17-y periodical cicadas (Magicicada cassini) on Konza Prairie Research Natural Area (KPRNA), Kansas, was quantified using emergence trap transects and counts of emergence holes. Emergence density, biomass (emergence production) and associated nitrogen flux were estimated for the entire 100 ha gallery forest of Kings Creek, the major drainage network on KPRNA. Emergence commenced on 22 May 1998 and lasted for 24 d, with 87% of the individuals emerging within the first 9 d. Males dominated early during the emergence, and the sex ratio for the entire population was estimated at 54:46 male:female. Average emergence abundance and biomass estimated from trap transects located in low areas where cicadas were most abundant were 152/m2 and 34.9 g ash-free dry mass (AFDM)/m2, respectively. Based on emergence hole counts, average density and biomass for the 59 ha of gallery forest where cicadas emerged were 27.2 individuals/m2 and 6.3 g AFDM/m2, and emergence hole densities >100/m2 were evident in low areas of the drainage. Emergence density generally decreased with increasing elevation in the catchment. Belowground to aboveground N flux associated with M. cassini emergence in high density areas was ∼3 g N/m2, and the average for the entire emergence area was 0.63 g N/m2. The total number of individuals that emerged from the Kings Creek riparian forest was estimated at 19.6 million, which represents 4.6 metric tons AFDM and ∼0.5 metric tons N. This linear, fragmented, gallery forest of the Flint Hills supports a high density of M. cassini, and an emergence event constitutes a significant belowground to aboveground flux of energy and nutrients. Thus, the periodical cicada may be an exception to the notion that insects generally do not represent important resource pools at the ecosystem level.

Feeding ecology and emergence production of annual cicadas (Homoptera: Cicadidae) in tallgrass prairie.

The emergence phenology and feeding ecology of annual cicadas in tallgrass prairie are poorly documented. However, these large insects are abundant, and their annual emergence represents a potentially important flux of energy and nutrients from belowground to aboveground. We conducted a study at Konza Prairie Research Natural Area in eastern Kansas to characterize and quantify cicada emergence and associated energy and nutrient fluxes. We established emergence trap transects in three habitat types (upland prairie, lowland prairie, and riparian forest), and collected cicadas every 3 days from May to September. A subset of trapped cicadas was used for species- and sex-specific mass, nutrient, and stable isotope analyses. Five species were trapped during the study, of which three were dominant. Cicadetta calliope and Tibicen aurifera exhibited significantly higher emergence production in upland prairie than in lowland prairie, and were not captured in forested sites at all. T. dorsata emerged from all three habitat types, and though not significant, showed a trend of greater abundance in lowland grasslands. Two less abundant species, T. pruinosa and T. lyricen, emerged exclusively from forested habitats. Nitrogen fluxes associated with total cicada emergence were estimated to be ∼4 kg N ha-1 year-1 in both grassland habitats, and 1.01 kg N ha-1 year-1 in forested sites. Results of stable isotope analyses showed clear patterns of resource partitioning among dominant cicada species emerging from grassland sites. T. aurifera and C. calliope had δ13C and δ15N signatures indicative of feeding on shallowly rooted C4 plants such as the warm-season grasses dominant in tallgrass prairie ecosystems, whereas T. dorsata signatures suggested preferential feeding on more deeply rooted C3 plants.

Role of Escape from Predators in Periodical Cicada (Homoptera: Cicadidae) Cycles

Evolution of unusually long life cycles and synchronized emergence of periodical cicadas, Magicicada spp., is one of the mysterious problems in evolutionary biology. Yoshimura presented a hypothesis to explain this by the elongation of the life cycle during glacial periods and the extinction of some yearclasses because of difficulty of mating in years of low adult density. Yoshimura assumes large fluctuations of abundance in ancient cicada populations, but cicada populations are far more stable than those of many other insects. By examining such data, I concluded that escape from predator pressure by synchronized massemergence is the most important factor for the evolution and maintenance of long-year periodicity, which has so far been found only in cicadas.

Epaulet Brightness and Condition in Female Red-Winged Blackbirds

Epaulets of female Red-winged Blackbirds (Agelaius phoeniceus) vary in bright- ness from brown to bright red-orange. We test predictions of the hypothesis that condition at the time of molt determines female epaulet brightness and that females in superior con- dition produce brighter epaulets. We compared each female's epaulet with a series of color photographs ranked from 1 (dull brown) to 12 (bright red-orange) and considered females to have increased in brightness between years if their color increased by at least two ranks. More first-year females than older females increased in brightness, more older females in- creased in brightness after low reproductive effort than after high effort, and more first-year females increased in brightness after a year of superabundant food (an emergence of periodical cicadas, Magicicada spp.) than after other years. In each case, we expected an improvement in condition. We estimated female condition and regressed condition index on day of the breeding season. During the breeding season, females that later increased in brightness improved in condition relative to females that did not increase in brightness. We confirm a previously reported correlation between age and epaulet brightness, but age does not explain the relationship between change in brightness and either reproductive effort or the emergence of cicadas. We conclude that the most likely explanation for our results is that condition, at least in part, determines epaulet brightness in female Red-winged Blackbirds and that superior condition is reflected by brighter epaulets. Our results support assumptions of the status- signaling hypothesis and mate-choice hypotheses for the evolution of variable plumage. The best explanation for the evolution of variable plumage among female Red-winged Blackbirds is that brightness signals status in female-female aggressive encounters. Received 21 November

Emergence of 13‐Yr Periodical Cicadas (Cicadidae: Magicicada): Phenology, Mortality, and Predators Satiation

We examined emergence of male and female 13—yr periodical cicadas (Brood XIX) and mortality, due to avain predation, fungal infection (Massospora cicadina), environmental factors, and senescence. We compared relative contributions of the sources of mortality, and determined the temporal pattern of avian predation associated with predator satiation and mortality. Based on a mean density of 6.65 emergence holes/m2, we estimated that 1 063 300 cicadas emerged on our 16—ha study area in northwestern Arkansas during May 1985. Males appeared first in emergence traps in early May and emerged more synchronously than did females. About 50% of the population emerged during four consecutive nights, and peak abundance of adult cicadas occurred in late May. Based on samples from mortality traps, at least 40% of the population died in severe thunderstorms during the first week of June, demonstrating the stochastic factors can be major influences on periodical cicada populations. Fungal infection was not a major source of mortality. The first cicadas that emerged in early May were eaten by birds, but avian predators became satiated. Birds consumed 15—40% of the standing crop at low cicada densities, but very little of the standing crop was consumed when cicada densities were &gt;24 000 individuals/ha on the study site. Avian predators appeared to be satiated for several weeks, and by the time their foraging activities increased due to demands imposed by feeding young, density of adult cicadas was relatively low. Mortality due to predation gradually increased to near 100% as the density of adult cicadas declined in June. Based on estimates of cicada emergence and deaths due to avian predation where adult cicada activity was greatest, birds consumed only °15% of the adult cicada population. Therefore, only a small proportion of the adult cicada population was actually consumed by avian predators. These results demonstrate that, indeed, the synchronized, explosive emergences of periodical cicadas may be classical examples of predator satiation.

A study of the abundance and patchiness of cicada nymphs (Homoptera: Tibicinidae) in a New Zealand subalpine shrub-grassland

Abstract Cicada emergence skins in a subalpine shrub grassland have been sampled during 1969–75 to determine the abundance and spatial distributions of nymphs feeding on plant roots. A guild of six cicada species is primarily associated with two forms of vegetation: shrubs (Dracophyllum and Cassinia) and tall tussock (Chionochloa). Skin locations were mapped relative to dominant vegetation species, litter zones, and soil and rock pavements over a range of aspects, altitudes, and vegetation types, and sampling methods were scaled at four levels: the locality, plot, quadrat, and individual plant. There were significant differences in skin counts over four years, and different measures of mean skin densities are given for the four sampling scales. The two primary vegetation types had cumulative 1969–72 mean densities of 5.2 ± 4.0 and 12.9 ± 10.0 skins/quadrat (2.3 m2) , and the 1969–72 mean productivities of the upper 25% of quadrats (adjusted for percent ground cover) were, respectively, 5.5 and 35.5 skins/...

Role of periodical cicadas (Homoptera: Cicadidae: Magicicada) in forest nutrient cycles

The relative contribution of an emergence of 13-year periodical cicadas to forest nutrient cycles was investigated in an upland forest in northwestern Arkansas during a mass emergence of Brood XIX in 1985. Nymphs were collected from below ground at two sites prior to emergence and adults of both sexes were collected at one site as they emerged from the ground and after emergence at a chorus center. Nymphs had higher levels of iron, aluminum, and manganese and lower levels of sodium and nitrogen than adults. Adult females had higher levels of potassium and phosphorus than adult males. Compared with annual litter fall, cicadas in the relatively low-density population studied represented less than 1% of any nutrient flux sampled in the litter fall. The most important ecosystem function of the cicadas in the forest of this study may be the increase in energy and nutrients available to predators.

Population Responses of Peromyscus leucopus and Blarina brevicauda to Emergence of Periodical Cicadas

-Periodical cicadas emerged in W-central Indiana in summer 1987, presenting forest-dwelling small mammals with an extremely abundant food supply. Population densities of white-footed mice Peromyscus leucopus did not increase in the year of cicada emergence compared with 7 yr without cicadas. However, the number of short-tailed shrews Blarina brevicauda increased by more than four-fold in the year of superabundant food.

Dynamics of periodical cicada chorus centers (Homoptera: Cicadidae:Magicicada)

Mating aggregations of three species of periodical cicadas were monitored during the emergence of Brood XIX at a 16-ha study site in northwest Arkansas, May–June 1985. Magicicada tredecassiniappeared first and formed the most choruses. M. tredecimand M. tredeculachoruses formed next, and M. tredeculachoruses outnumbered those of M. tredecim.Of the 268 choruses seen, 84% were composed of M. tredecassini. M. tredecassiniwere often found chorusing in the same trees with the other two species. Such multispecies mating aggregations apparently are unique to periodical cicadas. Choruses were dynamic with respect to their locations and durations. Initially, choruses were located near areas of high cicada emergence densities. One week later, cicadas chorused in trees throughout the forest and at the forest edge. Many choruses were seen only once at a location. Although cicadas chorused for almost 4 weeks, individual choruses persisted only approximately 8 days, on average. Sound intensities under chorus centers ranged from 50 to 80 dh and were correlated with arena sizes during times of peak chorus activity. No distinct habitat preferences of the three species were observed, however, the tree species used by chorusing cicadas differed among the species.

Control of the Periodical Cicada on Mountain-Ash, 1990

Abstract Control of the periodical cicada was evaluated in a planting of mountainash trees (2-3 m) located in a heavy cicada emergence area. Treatments were randomly applied at the onset of egg laying activity and repeated twice at 7 d intervals. Five trees were sprayed/treatment with each tree serving as a single replication. The trees were sprayed until run-off including the trunk, foliage, and all branches using a Solo°8 liter hand pressure sprayer. Temperature at time of application was 27°C and wind velocity was less than 5 mph. Field evaluation of insecticidal efficacy for prevention of ovipositional damage was conducted 14 DAT when all cicada activity had ceased. Due to differing growth habits of the study trees, a standard insecticidal efficacy variable of mean number of wounds/branch was identified and defined as the quotient of the total number of ovipositional wounds/tree over the total number of branches/tree greater than 4 mm in diam.

Seasonal cues in tropical organisms. Rainfall? Not necessarily!

Activity seasons of tropical organisms often start, on the average, at or about the beginning of the rainy or dry seasons. The hypothesis that the onset or cessation of the wet season provides the seasonal cues necessary of the initiation of the activity season of some tropical organisms is tested with data on Panamanian cicadas. Seasonal adult activity patterns are described for cicada species in Panama, mostly from Barro Colorado Island (BCI), some from Las Cumbres. In all species the correlation between the timing of the beginning and the end of the cicada season was low and not significant, so that the actual beginning data of a cicada season in a particular year had little or no predictive value for the end date. Seven out of eleven species on BCI started their average activity season at the average beginning of the dry season (one species) or rainy season (six species). Nevertheless, in 13 years, correlations between the start or end of the cicada seasons and that of the meteorological seasons were low and not significant. At best, the beginning and end of the rains played a minor role as seasonal cues governing cicada emergence or the termination of the cicada season. It is speculated that photoperiod might be a major seasonal cue governing emergence, through its effects on the host plants.

Soil Disturbance by the Emergence of Periodical Cicadas

AbstractSoil disturbance by animals is an important feature of soil genesis. This study evaluated the impact of cicada (Magicicada spp.) nymph emergence on soil redistribution in northern Kentucky forests. The excavation of burrows and the construction of turrets at burrow openings were the primary activities causing soil movement. The number of turrets ranged from 40 to 170 m−2, and quantity of soil deposited on the ground surface ranged from 626 to 2330 g m−2. Turret soil material came primarily from the A horizon. Nutrient concentrations in turret soil were significantly less than concentrations in the upper 5 cm of soil, except for P. Most cicada feeding cells were located in the AB horizon at depths of 7 to 36 cm.

Temporal Components of Reproductive Variability in Eastern Kingbirds (Tyrannus Tyrannus)

The influences of weather and food supply on Eastern Kingbird (Tyrannus tyrannus) reproduction were examined using data on annual (1980-1983) and seasonal variation in timing of breeding, clutch size, and egg mass in a population of kingbirds breeding in eastern Kansas, USA. Timing of breeding differed significantly among years and appeared to be related to insect abundance. Clutch size declined significantly with breeding date in all years, but differed significantly only between 1980 and 1981. A severe drought in 1980 likely depressed food availability, whereas an emergence of periodical cicadas in 1981 provided a superabundant food source. Across all years, however, clutch size varied inversely with the mean breeding date of the population, whereas average egg mass varied directly with food availability. Maximum annual differences in mean clutch and egg size were small compared to variation in food availability. I examined 10 hypotheses that have been proposed to explain seasonal changes of clutch size in birds. All but three were rejected as possible explanations for kingbirds. The tendency of older females to lay both earlier and larger clutches is probably responsible for most of the seasonal decline of clutch size, but reduced probability of survival for offspring fledged late in the breeding season and avoidance of stress in adults just prior to migration may also be contributing factors. Reduced clutch size late in the breeding period should permit females to hatch young sooner, to raise them faster, and to fledge them at higher masses. These features should increase survival of both juveniles and adults since postfledging care is long in kingbirds.

Effects of superabundant food on breeding success and behavior of the red-winged blackbird

The effects of food on breeding success and behavior of the red-winged blackbird (Icteridae: Agelaius phoeniceus) were investigated during 3 successive breeding seasons. In the second season, a 4-week pulse of abundant food in the form of a periodical cicada emergence (Homoptera: Cicadidae: Magicicada spp.) occurred in the forest adjacent to the marsh where the birds were breeding.During the cicada period, the bird population showed: 1) an increase in foraging trips to the forest and a decrease in trips per h, 2) increased biomass of nestlings, 3) increased nestling survival caused by decreased starvation, 4) increased fledging success, and 5) bimodal weight distributions of older nestlings (reflective of the sexual dimorphism in this species). These data suggest the temporary removal of food limitations on the breeding population when the pulse of food was available.

Increased Reproductive Success at High Densities and Predator Satiation For Periodical Cicadas

The reproductive success of periodical cicadas, measured as the number of offspring produced per adult, is found to increase as adult density increases. The inverse density—dependent pattern at the adult stage occurred over the entire range of adult densities encountered. This result could have been caused by (1) predator satiation, (2) increased fecundity at higher densities, (3) more efficient mating at higher densities, and (4) movement of adults from sites of low initial densities to sites of high densities. The hypothesis of predator satiation was explored in depth. Predation at each site was crudely estimated by collecting cicada wings, which are discarded by avian predators. If predator satiation accounts for the inverse density—dependent mortality, then each cicada's risk of capture will decrease as cicada density increases. The data suggest that this prediction is true; predation did not increase as cicada density increased so that the probability of escaping predation is greater at high—density sites. Estimated predator densities are independent of cicada densities, which indicates that predators cannot respond numerically to the cicada emergence. As cicada density increases, the number of cicada wings recovered per bird does not significantly increase, suggesting that birds are satiated. Significantly more cicada wings were recovered at sites with more birds. Total cicada predation was independent of cicada density but dependent on the density of predators. Some evolutionary consequences of these results are discussed.