Abundant Citizen Science Data Reveal That the Peacock Butterfly Aglais io Recently Became Bivoltine in Belgium

The peacock butterfly is abundant and widespread in Europe. It is generally believed to be univoltine (one generation per year): adults born in summer overwinter and reappear again in spring to reproduce. However, recent flight patterns in western Europe mostly show three peaks during the year: a first one in spring (overwintering butterflies), a second one in early summer (offspring of the spring generation), and a third one in autumn. It was thus far unclear whether this autumn flight peak was a second new generation or consisted of butterflies flying again in autumn after a summer rest (aestivation). The life cycle of one of Europe’s most common butterflies is therefore still surprisingly inadequately understood. We used hundreds of thousands of observations and thousands of pictures submitted by naturalists from the public to the online portal observation.orgin Belgium and analyzed relations between flight patterns, condition (wear), reproductive cycles, peak abundances, and phenology to clarify the current life history. We demonstrate that peacocks have shifted towards two new generations per year in recent decades. Mass citizen science data in online portals has become increasingly important in tracking the response of biodiversity to rapid environmental changes such as climate change.

Inter-sexual and inter-generation differences in dispersal of a bivoltine butterfly

In organisms with discrete generations such as most insects, life-history traits including dispersal abilities often vary between generations. In particular, density-dependent differences in dispersal of bi- and multivoltine species may be expected because subsequent generations are usually characterized by a drastic increase in individual abundance. We investigated the inter-sexual and inter-generation differences in dispersal of a bivoltine butterfly, Lycaena helle, testing the following hypotheses: (1) male emigration is higher in spring generation, as males are prone to leave their natal habitat patches when the density of mating partners is low; (2) female emigration is higher in summer generation, when it helps to reduce intraspecific competition between offspring. The outcome of our analyses of dispersal parameters showed that females of the summer generation emigrated from their natal patches considerably more often than those of the spring generation, whereas an opposite trend was detected in males. These findings offer a novel perspective for our understanding of the advantages of voltinism for metapopulation functioning. The spring generation dispersal mainly improves the random mating opportunities favoured by the increase in male emigration. In turn, the dispersal of females of the summer generation appears the key to long-term metapopulation persistence.

Shoot formation model (architectural model) Phlomoides oreophila

The morphological characteristics of Phlomoides oreophila, which grows in the Altai Mountains and Southeast Kazakhstan, are given. It is established that the species belongs to the monopodial-rosette model of shoot formation. The main structural unit is a perennial basal (skeletal) rosette shoot. Its annual growths form an epigeogenic oblique-orthotropic rhizome. An elementary shoot appears during 1 growth period and carries the vegetative and generative parts. The formula of the functional zones of the elementary shoot is determined: the inhibition zone → [innovation zone] → amplification zone → apical bud. It was established that the boundaries of the elementary and annual shoots do not coincide. Elementary shoot includes spring leaf generation (inhibition zone), summer leaf generation with axillary vegetative buds (innovation zone) and vegetative-generative buds (amplification zone). Vegetative-generative shoots appear only after wintering the following spring. They are located below the rosette leaves of the spring generation (this is the beginning of a new elementary shoot). As a result, the annual shoot includes the elementary shoot of the current year, as well as the amplification zone of the elementary shoot of last year.

Embryonic fertility and mortality of the Microtus arvalis species (Rodentia, Cricetidae) in the anthropic landscape

Embryonic fertility and mortality of the Microtus arvalis species (Rodentia, Cricetidae) in the anthropic landscape. The purpose of the paper was to study the embryonic fertility and mortality of Microtus arvalis individuals in the anthropic landscape. These parameters were analyzed based on a sample of 930 individuals. It has been determined that fertility increases from the first to the second gestation and there is an insignificant difference in the size of the offsprings of the generations of Microtus arvalis species that have wintered and in the number of the offsprings of the first spring generation.

The fungus Epichloë typhina in populations of a halophyte Puccinellia distans: salinity as a possible inhibitor of infection

<em>Puccinellia distans</em> is a non-agricultural halophytic grass that has become another host plant for <em>Epichloe typhina</em>, hitherto not reported from Poland. In 1992 we noticed the first symptoms of choke disease in a single population of <em>P. distans</em> in central Poland. Since then we have observed choke disease in 5 populations of <em>P. distans</em> only in man-made habitats. These habitats are strongly anthropogenically salinated but they exhibit the pattern of species composition characteristic of natural salines. In this paper we test the hypothesis that the level of salinity affects the infection of <em>P. distans</em> by the fungus <em>E. typhina</em>. Seven plots were established in the field and each plot was divided into 25 subplots. Within each plot the level of infection in a spring generation of shoots was negatively correlated with salinity (common regression within the plots, beta = -0.674, df = 117, p &lt; 0.001). Negative correlation was also found in an autumn generation within the plots (beta = -0.682, df = 94, p &lt; 0.001) after excluding plot P in which the frequency of infected individuals was the lowest and equal only to 0.05. The proportion of individuals infected by the endophytic stage of the fungus in the populations was assessed using diagnostic polymerase chain reaction. The greatest percentage (98.3%) of infected individuals was found in the population growing in the habitat of the lowest salinity. The high salinity reduces the chance of <em>P. distans</em> to become infected, but may promote the stroma formation of <em>E. typhina</em> twice in the season. Disease expression in autumn clearly represents a misadaptation which could be explained by the fact that the species interactions described here appeared relatively recently as a result of human activity. This hypothesis requires further experimental verification.

Influence of temperature and flowers on longevity of adult Platygaster demades

Failure by Platygaster demades to provide effective biological control of apple leaf curling midge (ALCM) may be because the second spring generation of the parasitoid is asynchronous with that of its host Asynchrony may result from relatively slow development of P demades at low temperatures in spring In laboratory experiments adult female P demades provided with honeyagar diet lived significantly longer at 11deg;C (479 28 days) than at 19deg;C (194 days) and 27deg;C (27 days) Platygaster demades were provided with fresh flowers of Anethum graveolens (dill) Coriander sativam (coriander) Fagopyrum esculentum (buckwheat) Lobularia maritime (alyssum) Phacelia tanacetifolia (purple tansy) and Sinapis alba (white mustard) Both sexes lived longest (and comparably to the honeyagar diet) when provided with buckwheat flowers The possibilities for using buckwheat in apple orchards to prolong the first generation of P demades sufficiently to synchronise with the second generation population of ALCM are discussed

Phenology and demography of Homalodisca coagulata (Hemiptera: Cicadellidae) in southern California citrus and implications for management

Populations of Homalodisca coagulata (Say) were sampled from citrus orchards in southern California, USA to characterize and quantify seasonal occurrences of nymphs and adults with the goal of identifying management opportunities through well-timed treatments and/or natural enemy releases. Higher densities of H. coagulata in 2001 contributed to a complete seasonal profile that began in early spring with the emergence of first instar nymphs and their progression through five nymphal instars lasting until mid-August. Adult emergence began in mid-June with peak adult densities attained from mid to late August followed by a gradual decline through autumn. A persistent and significant male bias was observed in the adult sex ratio from the time of first emergence through mid-October in oranges; the same trend was present in lemons, but with more variability. Adult densities gradually declined through the winter months into the following spring before rapidly increasing again in June as the 2002 spring generation of nymphs began emerging as adults. The seasonal timing of nymphs and adults in 2002 was nearly identical to that observed the previous year. Phenology data from both years were incorporated into a stochastic, temperature-dependent model that predicts the occurrences of H. coagulata stages through time. Applications of imidacloprid early in the spring generation of nymphs proved very effective at reducing nymphs and sustaining lower densities of adults through summer.

Factors supporting the non-persistence of fruit fly populations in South Australia

For purposes of interstate and international fruit trade, it is necessary to demonstrate that in areas in which fruit fly species have not previously established permanent populations, but which are subject to introductions of fruit flies from outside the area, the introduced population once detected, has not become established. In this paper, we apply methodology suggested mainly by Carey (1991, 1995) to introductions of Mediterranean fruit fly (Medfly), Ceratitis capitata Weid., and Queensland fruit fly (QFF) Bactrocera tryoni Froggatt (Diptera: Tephritidae) to South Australia, a state in which these species do not occur naturally and in which introductions, once detected, are actively treated. By analysing historical data associated with fruit fly outbreaks in South Australia, we demonstrate that: (i) fruit flies occur seasonally, as would occur in established populations, except there is no evidence of the critical spring generation of either species; (ii) there is no evidence of increasing frequency of outbreaks, trapped flies or larval occurrences over 29 years; (iii) there is no evidence of decreasing time between catches of adult flies as the years progress; (iv) there is no decrease in the mean number of years between outbreaks in the same locations; (v) there is no statistically significant recurrence of outbreaks in the same locations in successive years; (vi) there is no evidence of spread of outbreaks outwards from a central location; (vii) the likelihood of outbreaks in a city or town is related to the size of the human population; (viii) introduction pathways by road from Western Australia (for Medfly) and eastern Australia (for QFF) are shown to exist and to illegally or accidentally carry considerable amounts of fruit into South Australia; and (ix) there was no association between the numbers of either Queensland fruit fly or Medfly and the spatial pattern of either loquat or cumquat trees as sources of larval food in spring. This analysis supports the hypothesis that most fruit fly outbreaks in South Australia have been the result of separate introductions of infested fruit by vehicular traffic and that most of the resultant fly outbreaks were detected and died out within a few weeks of the application of eradication procedures. An alternative hypothesis, that populations of fruit flies are established in South Australia at below detectable levels, is impossible to disprove with conventional technology, but the likelihood of it being true is minimised by our analysis. Both hypotheses could be tested soon with newly developed genetic techniques.