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Large‐scale declines in insect abundances and richness due to climate and land‐use change have been well documented during the past years. These changes are accompanied by shifts in insect phenology towards earlier appearance in spring and prolonged activity periods in late summer and autumn. The magnitude of these responses to climate change might be masked by intra‐ and inter‐specific variability in phenology and trait expression. Here, we used a large data set of museum records of butterflies from the northern Austrian Alps (380 m to >3000 m asl) and ask to which degree does intra‐ and inter‐specific variability in spring and autumn activity and in the numbers of generations affect the temporal trends in phenology during the last 30 years? For the 17 most abundant species, we found phenological variability to strongly differ among species, local habitats and study years. Ubiquitous mobile species were significantly more variable than habitat specialist and sedentary species. Intra‐specific variability was highest in ubiquitous habitat generalist species and increased during the study period. As consequence, seasonal appearance and composition of local butterfly communities are now less predictable than decades ago. It remains unclear whether this trend causes a rewiring of pollinator food webs. [ABSTRACT FROM AUTHOR]

Simple Summary: This study investigated the impact of climate change on the phenology of Carposina sasakii in China using historical data. The findings reveal that overwintering adults' first occurrence and population peak dates have generally advanced in eastern, northwestern, and northern regions, except for a delay in Jilin. For first-generation adults, first occurrence dates have shifted earlier in northeast, east, and central China but delayed in northwest and northern parts. Significant delays were observed in population peaks and end occurrences in provinces like Gansu, Shaanxi, and Liaoning. Pearson correlation analyses confirm spatial heterogeneity in C. sasakii's responses to warming temperatures. These insights are crucial for monitoring and managing peach fruit moth populations amidst climate change. It is widely recognized that the phenology of insects, of which the life activities are closely tied to temperature, is shifting in response to global climate warming. This study aimed to investigate the impacts of climate change on the phenology of Carposina sasakii Matsumura, 1900 (Lepidoptera: Carposinidae) across large temporal and spatial scales, through collecting and systematically analyzing historical data on the pest's occurrence and population dynamics in China. The results showed that for overwintering adults, the first occurrence date in eastern, northwestern, and northern China has significantly advanced, along with the population peak in eastern and northwestern China. At the provincial level, the population peak date in Shandong province has also moved significantly earlier, as well as the population peak date in Shandong and Shaanxi and the end occurrence date in Ningxia. However, the population peak date in Jilin has experienced a delayed trend. For first-generation adults, the first occurrence date in northeastern, eastern, and central China has notably advanced, while the first appearance date in northwestern and northern China has significantly delayed. Additionally, the population peak in northwestern China has experienced significant delays, along with the final occurrence in northeastern and northwestern China. At the provincial level, the first occurrence date in Liaoning, Shandong, and Shanxi has significantly advanced, while Hebei has demonstrated a significant delay. The population peak time in Gansu and Shaanxi has displayed significant delays, and the end occurrence date in Liaoning, Shanxi, and Shaanxi has also shown significant delays. Furthermore, these findings integrated with the Pearson correlation results reveal spatial heterogeneity in C. sasakii's phenological responses to climate warming at both regional and provincial scales. The phenology of C. sasakii and their changing patterns with climate warming vary by geographical location. This study provides valuable information for the future monitoring, prediction, and prevention of peach fruit moths in the context of climate warming. [ABSTRACT FROM AUTHOR]

The management of forest pests relies on an accurate understanding of the species' phenology. Thermal performance curves (TPCs) have traditionally been used to model insect phenology. Many such models have been proposed and fitted to data from both wild and laboratory-reared populations. Using Hamiltonian Monte Carlo for estimation, we implement and fit an individual-level, Bayesian hierarchical model of insect development to the observed larval stage durations of a population reared in a laboratory at constant temperatures. This hierarchical model handles interval censoring and temperature transfers between two constant temperatures during rearing. It also incorporates individual variation, quadratic variation in development rates across insects' larval stages, and "flexibility" parameters that allow for deviations from a parametric TPC. Using a Bayesian method ensures a proper propagation of parameter uncertainty into predictions and provides insights into the model at hand. The model is applied to a population of eastern spruce budworm (Choristoneura fumiferana) reared at 7 constant temperatures. Resulting posterior distributions can be incorporated into a workflow that provides prediction intervals for the timing of life stages under different temperature regimes. We provide a basic example for the spruce budworm using a year of hourly temperature data from Timmins, Ontario, Canada. Supplementary materials accompanying this paper appear on-line. [ABSTRACT FROM AUTHOR]

Diapause is a vital survival strategy for insects, enabling them to conserve energy and endure adverse conditions. Understanding how diapause affects insect phenology and population dynamics is crucial for the effective management of insect pests. Predictive pest phenological models can be invaluable tools for providing essential information to support management strategies. This study presents a modelling framework to incorporate diapause into phenological models when biological information on variables regulating and functions describing diapause induction and termination are lacking or limited. In our framework, insect phenology is divided into a set of phases characterized by specific events (diapause induction and termination) and processes (development of diapausing and post‐diapausing biological stages). The phenology is simulated by a stage‐structured model based on the Kolmogorov equation, and the temperature‐dependent development rate functions are described by the Brière functional form. Our modelling framework was tested on a case study involving the prediction of the phenology of the codling moth, (Cydia pomonella L. 1758). Model calibration and validation were performed using four time‐series adult trap catch data collected in the Emilia Romagna Region from 2021 to 2023. The calibration procedure allowed obtaining realistic parameters related to the temperature threshold triggering diapause termination and the development rate function of post‐diapausing larvae and pupae. Model validation proved successful in simulating both the initial emergence and the overall phenological patterns of adults across the three observed generations. The methodological framework proposed here aims to facilitate the introduction of diapause in phenological models improving also their predictive abilities. The model may serve as an accurate and knowledge‐based tool for planning and implementing pest monitoring and control actions based on the realistic predictions provided by the model on the phenological status of the pest. [ABSTRACT FROM AUTHOR]

Climate change and global warming in the Sahelian region cause dramatic drought and advancing of the desert. This phenomenon could affect the plant survival and community composition, but even for surviving plants, it could affect their phenology and the insect community associated with them. In a space‐for‐time approach, we studied the case of Annona senegalensis Pers. (Annonaceae), a common shrub in tropical areas, to determine the impact of climate change on its phenology and the insects associated with its flowers and fruits. We determined the phenology phases of Annona senegalensis during a 1‐year period and assessed the abundance and diversity of insects in the Sudanian and the Sudano‐Sahelian climatic zones of Burkina Faso. Temperature, rainfall and relative humidity were recorded during 12 months in two sites per zone. Leafing of Annona senegalensis lasted 10 months in the Sudanian zone, flowering and fruiting were 3 months long. In the Sudano‐Sahelian zone, leafing lasted 8 months while flowering and fruiting were 3 and 4 months long, respectively. A total of 10,040 insects belonging to 48 species were collected in the two climatic zones. Forty‐six species were found in the Sudanian zone while 25 species were recorded in the Sudano‐Sahelian one. The variations in the plant phenology and the insect community were mainly due to the variation in rainfall across both climatic zones. Our results emphasize that advancing of the desert due to climate change could not only affect the survival of plants but for resistant species it also affect their interactions with insects and the whole insect community associated. [ABSTRACT FROM AUTHOR]

Agroclimatic variables may affect insect and plant phenology, with unpredictable effects on pest populations and crop losses. Bactrocera oleae Rossi (Diptera: Tephritidae) is a specific pest of Olea europaea plants that can cause annual economic losses of more than one billion US dollars in the Mediterranean region. In this study, we aimed at understanding the effect of olive tree phenology and other agroclimatic variables on B. oleae infestation dynamics in the Umbria region (Central Italy). Analyses were carried out on B. oleae infestation data collected in 79 olive groves during a 7-year period (from 2015 to 2021). In July-August, B. oleae infestation (1% attack) was negatively affected by altitude and spring mean daily temperatures and positively by higher wintermean daily temperatures and olive tree cumulative degree days. In September-October, infestation was negatively affected by a positive soil water balance and high spring temperatures. High altitude and cumulative plant degree days were related to delayed attacks. In contrast, high winter and spring temperatures accelerated them. Our results could be helpful for the development of predictive models and for increasing the reliability of decision support systems currently used in olive orchards. [ABSTRACT FROM AUTHOR]

Plants that bloom in early spring often face constraints on reproduction, which are influenced by low temperatures and unpredictable weather conditions that affect pollinator activity. We aimed to elucidate the pollination ecology and the mating system of Ranzania japonica (Berberidaceae), a perennial plant of a monotypic genus endemic to deep‐snow regions in Japan. We documented the flowering phenology and visiting insects in the field, and conducted pollination experiments by using artificial treatments. R. japonica was suggested to be self‐incompatible but not pollen‐limited. Fruit set varied between years, and florivory seemed to have a negative influence on fruit set. Insects from various taxa were observed to visit the flowers of R. japonica, with Eusphalerum sp. (rove beetle) being the most abundant, followed by Bombylius major and hymenopteran species. The stamen movement in response to insect visits was observed. The results of the observation and the pollination treatments suggested that small‐ and medium‐sized Hymenoptera were the main pollinators and rove beetles may also contribute to pollination in R. japonica. Because early spring weather can be unsuitable for activity of bees, rove beetles may act as supplementary pollinators of R. japonica. The role of the supplementary pollinators may be an overlooked but important aspect for understanding the pollination biology of early‐spring blooming plants. [ABSTRACT FROM AUTHOR]

Solitary and primitively eusocial bees, an important group of pollinators, have declined in the past few decades. In view of the recent focus on safeguarding pollinating insects, it is vital to understand the basic ecology of species for their conservation, for example their phenologies. We observed the flight periods of solitary and primitively eusocial bees in both the urban core of a large British town and nearby nature conservation areas. The bee surveys were conducted with standardised methods, on warm sunny days from the first appearance of bees in March 2012 and continued until October 2012. This study confirmed that a high number of species are active in the spring season. The emergence dates of species in urban areas and nature sites varied; about 26 of the 35 species were recorded at least one week earlier in urban areas; in contrast, only four species were seen earlier in nature conservation sites. When comparing this with the expected flight periods recorded (largely in nature sites) in the literature, many species were recorded at their expected time. However, a few individuals were recorded after their usual flight activity time, suggesting that the populations were possibly affected by the microclimate in urban areas. More urban phenological data are needed to understand the phenological trends in bees in urban habitats. [ABSTRACT FROM AUTHOR]

The more insects there are, the more food there is for insectivores and the higher the likelihood for insect-associated ecosystem services. Yet, we lack insights into the drivers of insect biomass over space and seasons, for both tropical and temperate zones. We used 245 Malaise traps, managed by 191 volunteers and park guards, to characterize year-round flying insect biomass in a temperate (Sweden) and a tropical (Madagascar) country. Surprisingly, we found that local insect biomass was similar across zones. In Sweden, local insect biomass increased with accumulated heat and varied across habitats, while biomass in Madagascar was unrelated to the environmental predictors measured. Drivers behind seasonality partly converged: In both countries, the seasonality of insect biomass differed between warmer and colder sites, and wetter and drier sites. In Sweden, short-term deviations from expected season-specific biomass were explained by week-to-week fluctuations in accumulated heat, rainfall and soil moisture, whereas in Madagascar, weeks with higher soil moisture had higher insect biomass. Overall, our study identifies key drivers of the seasonal distribution of flying insect biomass in a temperate and a tropical climate. This knowledge is key to understanding the spatial and seasonal availability of insects—as well as predicting future scenarios of insect biomass change. [ABSTRACT FROM AUTHOR]

The increase of environmental temperature due to current global warming is not only favouring the expansion of the distribution range of many insect species, but it is also changing their phenology. Insect phenology is tightly linked to developmental timing, which is regulated by environmental temperatures. However, the degree to which the effects of developmental temperatures extend across developmental stages and their inter‐stage relationships have not been thoroughly quantified in mosquitoes. Here, we used the mosquito Aedes albopictus, which is an aggressive invasive species and an arboviral vector, to study how developmental temperature influences fitness across developmental stages, thermal traits, energy reserves, transcriptome and Wolbachia prevalence in laboratory‐reared populations originally collected from either temperate or tropical regions. We show that hatchability, larval and pupal viability and developmental speed are strongly influenced by temperature, and these effects extend to wing length, body mass, longevity and content of water, protein and lipids in adults in a population‐specific manner. On the contrary, neither adult thermal preference nor heat resistance significantly change with temperature. Wolbachia density was generally lower in adult mosquitoes reared at 18°C than at other tested temperatures, and transcriptome analysis showed enrichment for functions linked to stress responses (i.e. cuticle proteins and chitin, cytochrome p450 and heat shock proteins) in mosquitoes reared at both 18 and 32°C. Our data showed an overall reduced vector fitness performance when mosquitoes were reared at 32°C, and the absence of isomorphy in the relationship between developmental stages and temperature in the laboratory population deriving from larvae collected in northern Italy. Altogether, these results have important implications for reliable model projections of the invasion potentials of Ae. albopictus and its epidemiological impact. [ABSTRACT FROM AUTHOR]

Climate change is causing a shift in long-term weather patterns and altering parameters such as temperature, atmospheric CO2, and precipitation patterns. It is likely to be an indirect effect of greenhouse gases and their enhancement in the atmosphere largely induced by human activities. As poikilothermic animals, insects are highly dependent on environmental conditions, particularly temperature, which affects various aspects of their life. Climate change have a direct impact on insect pests by affecting their population dynamics, diurnal activity, growth rate and diapause. It may lead to a range expansion, increased overwintering survival, more generations per year, elevated risk of invasive insect species and insect-borne plant diseases, and changes in their interactions with host plants and natural predators. Indirectly, changes in climate can modify host plants and competitors, further complicating the effect on insect biology and phenology. Impact of elevated CO2 levels on their host plants can affect growth rates, fecundity, and population densities of insects. Altered precipitation patterns, such as droughts and floods, affect insect survival and diapause. Further, there is significant implications of climate change on different aspects of insect ecology, including insect distribution, behavior, and communication. The climate changes are predicted to alter the geographic ranges and migration behavior of insect species, creating new ecological niches and removing low-temperature barriers. These changes can threaten food security and increase the latitudinal and altitudinal range of crop pests. It also affects natural enemies, which can decrease the plant defense system against insect pests. Additionally, climate change can affect pheromonal communication, including production to behavioral response, in insects that rely on long-range chemical signals for communication. The review paper highlights the potential impacts of climate change on insect biological, phenological and ecological aspects. [ABSTRACT FROM AUTHOR]

Simple Summary: Phenological maps can depict the development and seasonal activities (phenology) of invasive insects at area-wide scales, such as counties, states, or entire nations. When regularly updated using real-time and forecast climate data, these maps may improve the timeliness of early detection and control tactics that target specific life stages. Rapid responses to invasive insects may increase the likelihood that populations are eradicated or controlled before they can spread or increase in size. In this review, we provide a brief history of phenological mapping, compare three types of maps that are commonly used for real-time decision support, and summarize climate datasets that may be used for mapping. We also present applications of phenological maps for assessing establishment risk, investigating pest–host interactions, and measuring climate-driven changes in pest phenology. Next, we discuss model complexity, potential sources of model error and uncertainty, methods for evaluating map predictions, and recommendations for future research. The development of additional real-time climate datasets and pest models will allow expanded use of phenological maps to help control invasive insects under current and future climates. Readily accessible and easily understood forecasts of the phenology of invasive insects have the potential to support and improve strategic and tactical decisions for insect surveillance and management. However, most phenological modeling tools developed to date are site-based, meaning that they use data from a weather station to produce forecasts for that single site. Spatial forecasts of phenology, or phenological maps, are more useful for decision-making at area-wide scales, such as counties, states, or entire nations. In this review, we provide a brief history on the development of phenological mapping technologies with a focus on degree-day models and their use as decision support tools for invasive insect species. We compare three different types of phenological maps and provide examples using outputs of web-based platforms that are presently available for real-time mapping of invasive insects for the contiguous United States. Next, we summarize sources of climate data available for real-time mapping, applications of phenological maps, strategies for balancing model complexity and simplicity, data sources and methods for validating spatial phenology models, and potential sources of model error and uncertainty. Lastly, we make suggestions for future research that may improve the quality and utility of phenological maps for invasive insects. [ABSTRACT FROM AUTHOR]

Populations wax and wane over time in response to an organism's interactions with abiotic and biotic forces. Numerous studies demonstrate that fluctuations in local populations can lead to shifts in relative population densities across the geographic range of a species over time. Fewer studies attempt to disentangle the causes of such shifts. Over four decades (1983–2022), we monitored populations of hibernating Indiana bats (Myotis sodalis) in two areas separated by ~110 km. The number of bats hibernating in the northern area increased from 1983 to 2011, while populations in the southern area remained relatively constant. We used simulation models and long‐term weather data to demonstrate the duration of time bats must rely on stored fat during hibernation has decreased in both areas over that period, but at a faster rate in the northern area. Likewise, increasing autumn and spring temperatures shortened the periods of sporadic prey (flying insect) availability at the beginning and end of hibernation. Climate change thus increased the viability of northern hibernacula for an increasing number of bats by decreasing energetic costs of hibernation. Then in 2011, white‐nose syndrome (WNS), a disease of hibernating bats that increases energetic costs of hibernation, was detected in the area. From 2011 to 2022, the population rapidly decreased in the northern area and increased in the southern area, completely reversing the northerly shift in population densities associated with climate change. Energy balance during hibernation is the singular link explaining the northerly shift under a changing climate and the southerly shift in response to a novel disease. Continued population persistence suggests that bats may mitigate many impacts of WNS by hibernating farther south, where insects are available longer each year. [ABSTRACT FROM AUTHOR]

Spring phenological synchrony can be important for tree‐insect interactions. Depending on the magnitude and direction of phenological shifts, overwintering insects could be affected in many ways, for example, facing starvation or having to contend with increased chemical or physical defences of host trees. If temperature has different influences on the phenology of trees and insects, climate change can alter spring phenological synchrony.In this experiment, we exposed tamarack seedlings and larch case bearer larvae from Minnesota, USA, to a variety of chilling and forcing temperatures and measured spring phenology (twig bud break and larval activation). We additionally measured case bearer performance on seedlings that were exposed to different forcing × chilling levels, tracking larval survivorship to adulthood.Warmer forcing enhanced larval activation and bud break, but larval development slowed down past 21°C. Higher chilling temperatures accelerated bud break, but the effect was inconclusive for larvae. There was no chilling × forcing interaction for either species. Spring activity accelerated more quickly with increases in temperature for larvae than for seedlings, resulting in increased phenological synchrony at warmer temperatures. Activation rates for overwintering larvae were highest at 27°C, while survivorship to adulthood following spring activation was highest at 21°C. At temperatures at or beyond 27°C, no larvae reached adulthood.Warmer winters and springs will likely initially increase spring synchrony between tamarack and larch case bearer, exposing larvae to younger, potentially more nutritious foliage, but extremely warm spring temperatures may decrease survivorship of larvae to adulthood. [ABSTRACT FROM AUTHOR]

We then modeled the residuals of these models against: (a) temperature; (b) temperature and its quadratic; (c) temperature and its cubic; and (d) temperature as a saturating exponential decay. The extremity of recent phenology is stark: during this 10 SP th sp decade of study, the record for the highest average annual temperature was broken six times and, in 2021 alone, species at nine of the 72 sites exhibited the earliest flowering phenology ever recorded. Keywords: climate change; flowering; Korea Meteorological Agency; phenological variance; woody plant phenology EN climate change flowering Korea Meteorological Agency phenological variance woody plant phenology 824 829 6 07/03/23 20230801 NES 230801 Data availability All reproducible analysis codes are released in the Supporting Information; the data are housed with the Korean Meteorological Agency and are also released in the Supporting Information. Climate change, flowering, phenological variance, Korea Meteorological Agency, woody plant phenology. [Extracted from the article]

Recent insect abundance declines may have affected populations of insectivorous bird species but evidence for this is limited. Here, we use spatially overlapping 29‐year time‐series of aerial insect biomass and Barn Swallow Hirundo rustica numbers and breeding success from southern England to model the association between changes in invertebrate prey abundance, Swallow productivity and population trends. We found a positive statistical relationship between Swallow chick survival and the biomass of aerial insects available for chicks. In nests where at least one chick fledged, 96.7% of chicks were predicted to survive to fledging where there was high insect biomass (an average of 0.62 g/day), compared with 87.4% of chicks surviving to fledging where there was the lowest insect biomass (0.02 g/day; excluding the greatest and smallest 5% of insect biomass measurements). The amount of food available for chicks was largely a function of annual variation in insect abundance rather than the phenology of egg‐laying and insect emergence. However, we did not find a correlation between annual insect abundance and subsequent Swallow population growth. In the context of concerns about declining insect abundance, this study shows how changes in insect biomass may affect the productivity of an insectivorous bird at a regional scale, but with uncertain implications for population size at that same scale. [ABSTRACT FROM AUTHOR]

It is well accepted that the phenology of insects whose life activities are closely related to temperature is changing in response to global climate warming. To investigate the impacts of climate warming on the phenology of Bactrocera dorsalis (Hendel) across large temporal and spatial scales, this study collected historical data on the occurrence and population dynamic of this pest in China, and systematically explored its phenological responses. The results showed a delayed trend for the dates of first occurrence, end occurrence, population initial growth, and population peak of B. dorsalis in China during 40 years, and the changes of the latter two phenological parameters were significant. The mean temperature in spring and summer were the key climatic factors affecting the occurrence and population growth of B. dorsalis in China, respectively. Moreover, the B. dorsalis data in eastern, southern, central, and southwestern China showed spatial heterogeneity of phenological responses to climate warming at a regional scale. B. dorsalis phenology and their changing patterns with climate warming varied by geographical location. This study provides valuable information for future monitoring, prediction, and prevention of the oriental fruit fly in the context of climate warming. [ABSTRACT FROM AUTHOR]

Although corn production is affected by several harmful insects, its most important pest in the southeastern region of Europe is the European corn borer (ECB), Ostrinia nubilalis Hübner, 1796 (Lepidoptera: Pyralidae). Chemical control of O. nubilalis remains the main strategy in conventional corn production. The key to successfully achieving a high efficiency of insecticides is determining the appropriate moment of application, including the exact time in the insect's life cycle when it is most vulnerable. In this study, monitoring data on the flight dynamics of ECB adults from a seven-year period (2014–2020) were exploited for the development of a predictive model of adult numbers within the growing season. ECB monitoring was performed by using light traps at 15 different locations in the Vojvodina region (Serbia) during the specified time period. First, the calendar for Vojvodina was created based on the analytics of the collected monitoring data. Additionally, the calendar was converted to the probability of ECB occurrence during the growing season, specifying the time interval between the appearance of each generation of the pest. Second, using machine learning techniques, a phenological model was designed that included daily values of relevant meteorological features, such as cumulative degree-days, relative humidity, and precipitation. The calendar had a lower prediction error when compared to the phenological model, and it was tested as a supporting management tool for the ECB in 2021, with a root-mean-square error of the number of adults of 46.67. Such an approach could significantly reduce both the consumption of insecticides and the number of chemical treatments, respectively. Above all, this approach has broad potential in IPM and organic farming, and it is fully compatible with biological control methods. [ABSTRACT FROM AUTHOR]

Studies of long-term trends in phenology often rely on climatic averages or accumulated heat, overlooking climate variability. Here we test the hypothesis that unusual weather conditions are critical in driving adult insect phenology. First, we generate phenological estimates for Lepidoptera (moths and butterflies) across the Eastern USA, and over a 70 year period, using natural history collections data. Next, we assemble a set of predictors, including the number of unusually warm and cold days prior to, and during, the adult flight period. We then use phylogenetically informed linear mixed effects models to evaluate effects of unusual weather events, climate context, species traits, and their interactions on flight onset, offset and duration. We find increasing numbers of both warm and cold days were strong effects, dramatically increasing flight duration. This strong effect on duration is likely driven by differential onset and termination dynamics. For flight onset, impact of unusual climate conditions is dependent on climatic context, but for flight cessation, more unusually cold days always lead to later termination particularly for multivoltine species. These results show that understanding phenological responses under global change must account for unusual weather events, especially given they are predicted to increase in frequency and severity. Butterfly phenology appears more strongly influenced by extreme weather events, such as unusually hot or cold days, than by mean temperatures over the year. [ABSTRACT FROM AUTHOR]

Climate change models often assume similar responses to temperatures across the range of a species, but local adaptation or phenotypic plasticity can lead plants and animals to respond differently to temperature in different parts of their range. To date, there have been few tests of this assumption at the scale of continents, so it is unclear if this is a large‐scale problem. Here, we examined the assumption that insect taxa show similar responses to temperature at 96 sites in grassy habitats across North America. We sampled insects with Malaise traps during 2019–2021 (N = 1041 samples) and examined the biomass of insects in relation to temperature and time of season. Our samples mostly contained Diptera (33%), Lepidoptera (19%), Hymenoptera (18%), and Coleoptera (10%). We found strong regional differences in the phenology of insects and their response to temperature, even within the same taxonomic group, habitat type, and time of season. For example, the biomass of nematoceran flies increased across the season in the central part of the continent, but it only showed a small increase in the Northeast and a seasonal decline in the Southeast and West. At a smaller scale, insect biomass at different traps operating on the same days was correlated up to ~75 km apart. Large‐scale geographic and phenological variation in insect biomass and abundance has not been studied well, and it is a major source of controversy in previous analyses of insect declines that have aggregated studies from different locations and time periods. Our study illustrates that large‐scale predictions about changes in insect populations, and their causes, will need to incorporate regional and taxonomic differences in the response to temperature. [ABSTRACT FROM AUTHOR]

Nineteen insect species from four major insect orders viz., Hemiptera, Lepidoptera, Coleoptera, and Orthoptera, were found belong to sixteen families damaging common bean, which is also known as French bean cultivation in subtropical climates. Among the insect pests, sucking insects occupies maximum incidence; aphid, Aphis craccivora Koch incidence was peak in both seasons 2018 (77.4 aphids/plant) and 2019 (77.6 aphids/plant) during 8th SMW followed by Leafhoppers, Empoasca kerri Pruthi (6.4 Nos/plant). The impact of weather factors on the insect populations showed that minimum temperature negatively correlated with aphids (r =—0.189), leafhopper (r = -0.315) populations and positively correlated with whitefly, Bemisia tabaci Gennadius (r = 0.118) and thrips, Thrips palmi Karny population (r = 0.052). Relative humidity and rainfall were negatively correlated with French bean sucking pests. In defoliators, serpentine leaf miner, Liriomyza trifolii Burgess larvae incidence was high in both seasons (18.4 larva/plant) and (20.6 larva/plant) followed by hairy caterpillar, Euproctis fraterna Moore (1.4 larva/plant) and leaf folder, Nacoleia spp (1.15 larvae/plant). Among the pod borers, spotted pod borer, Maruca vitrata incidence was higher than others and influenced by both maximum (r = 0. 791) and minimum temperature (r = 0.714). Relative humidity and wind speed parameters were negatively correlated with pod borers viz., M. vitrata Fabricius and Helicoverpa armigera Hubner respectively. The model ARIMAX (3, 0, 0) of aphids showed that the incidence of the pest depended on the weather parameters such as minimum temperature, relative humidity, and rainfall significantly. The ARIMAX (2, 0, 0) model of M. vitrata showed that the weather parameters such as maximum temperature, minimum temperature and relative humidity played a significant role in the incidence of the M. vitrata. [ABSTRACT FROM AUTHOR]

The black cut worm Agrotis ipsilon (Hufnagel) is a destructive crop pest worldwide and a typical cut worm damaging plant parts below the soil surface, which requires a thorough phenological prediction of the target stage for proper management. Temperature is an essential factor affecting the phenology and dynamics of insect populations. So, this study was conducted to evaluate the temperature-dependent development of A. ipsilon fed on Kimchi cabbage (Brassica campestris) in a wide range of temperatures (10 to 40 ℃) in the laboratory. The linear and nonlinear relationship between temperature and development rate (1/development time) was analyzed. The lower threshold temperatures (LT) for eggs, larvae, and pupae were estimated to be 12.1 °C, 9.6 °C, and 11.2 °C, respectively, with thermal constants (degree days for development completion) of 31.3, 342.2, and 181.3 DD at each stage, respectively. Additionally, the thermal constant for tracking the phenology of each stage was determined using a common LT of 10.4 ℃: 40.3 DD for eggs, 315.6 DD for larvae, and 199.6 DD for pupae. Consequently, we provided newly the stage transition models for all stages of A. ipsilon using two basic components of the nonlinear development rate and distribution models to simulate the proportion of individuals shifted from one stage to the next stage. These models in their current form will be useful for constructing a population model for A. ipsilon in the future. Furthermore, the variation in the development time of A. ipsilon reported in previous studies was discussed using 95% confidence limits of the estimated line of our nonlinear models. [ABSTRACT FROM AUTHOR]

Larvae and pupae of Depressaria halophilella Chrétien, 1908 (Lepidoptera: Depressariidae) are rarely found. The available data about the biology and phenology come from only a few observations. This article provides additional information on this species, thanks to some recent finds in Sardinia that are described and illustrated here. [ABSTRACT FROM AUTHOR]

Simple Summary: Giant pine scale, Marchalina hellenica Gennadius (Hemiptera, Marchalinidae), is a sap sucking insect native to the Eastern Mediterranean Basin. In 2014, giant pine scale was detected for the first time in Victoria, Australia, feeding on a new host, Pinus radiata. We studied the life cycle and feeding activity of giant pine scale in Victoria over 32 months, with the aim of drawing comparisons between exotic and native populations. Australian life stages of this pest emerged during similar months to Greek seasonal equivalents, although the timing of Australian life stages differed between years. Insect density and feeding activity on infested trees differed among locations and between generations. Strong evidence was found in support of density and feeding intensity being explained by climatic conditions. The value of Pinus radiata as a food source for this insect may fluctuate with climate conditions. Our findings aim to inform future management efforts for this scale insect, including surveillance strategies and optimal seasons for release of biocontrol agents. Our findings also suggest that the impact of this pest in Australia may be exacerbated by climate change. Invasive insects pose an increasing risk to global agriculture, environmental stability, and public health. Giant pine scale (GPS), Marchalina hellenica Gennadius (Hemiptera: Marchalinidae), is a phloem feeding scale insect endemic to the Eastern Mediterranean Basin, where it primarily feeds on Pinus halepensis and other Pinaceae. In 2014, GPS was detected in the southeast of Melbourne, Victoria, Australia, infesting the novel host Pinus radiata. An eradication program was unsuccessful, and with this insect now established within the state, containment and management efforts are underway to stop its spread; however, there remains a need to understand the insect's phenology and behaviour in Australia to better inform control efforts. We documented the annual life cycle and seasonal fluctuations in activity of GPS in Australia over a 32 month period at two contrasting field sites. Onset and duration of life stages were comparable to seasons in Mediterranean conspecifics, although the results imply the timing of GPS life stage progression is broadening or accelerating. GPS density was higher in Australia compared to Mediterranean reports, possibly due to the absence of key natural predators, such as the silver fly, Neoleucopis kartliana Tanasijtshuk (Diptera, Chamaemyiidae). Insect density and honeydew production in the Australian GPS population studied varied among locations and between generations. Although insect activity was well explained by climate, conditions recorded inside infested bark fissures often provided the weakest explanation of GPS activity. Our findings suggest that GPS activity is strongly influenced by climate, and this may in part be related to changes in host quality. An improved understanding of how our changing climate is influencing the phenology of phloem feeding insects such as GPS will help with predictions as to where these insects are likely to flourish and assist with management programs for pest species. [ABSTRACT FROM AUTHOR]

Better empirical knowledge of how bat and insect phenology are influenced by seasonal environmental conditions and how this may affect fitness is essential in the face of changing climatic conditions. We examined the winter diet of the Schreibers' bent-winged bat Miniopterus schreibersii (Kuhl, 1817) from Razhishkata Cave, Balkan Mountains, Bulgaria during four sampling periods in the winter of 2021 (end of January -- end of March). We used a combination of DNA metabarcoding and a microscope-based morphological analyses of bats droppings. Additionally, we tracked prey availability in the studied area using insect flight interception traps (FIT). The species was actively feeding outside the cave and did not use the cave fauna. Our samples indicate a shift in the winter diet of the bats throughout the studied periods. Even though Diptera was the most abundant order of insects during two of the study periods, bats were preying predominantly on Lepidoptera and Hymenoptera. The metabarcoding also supported this with data for the presence of insects with diurnal activity in the samples. The temperature loggers showed a strong correlation between the outside temperature and the temperature in the cave where the colony was located, probably impacting the activity patterns of the bats. To our knowledge, this is the first study of winter bat activity and diet in Bulgaria. Our research can serve as a potential framework for studying winter bat activity and insect activity during this sensitive period. [ABSTRACT FROM AUTHOR]

Exposure of freshwater ecosystems to insecticides can negatively impact the development of emerging aquatic insects. These insects serve as an important nutritional subsidy for terrestrial insectivores. Changes in insect emergence phenology (i.e., emergence success and temporal pattern) or fluxes of insecticides retained by the emerging adults have the potential to negatively impact terrestrial food webs. These processes are influenced by contaminant toxicity, lipohilicity, or metabolic processes. The interplay between emergence phenology, contaminant retention through metamorphosis, and associated contaminant flux is not yet understood for current‐use insecticides. In a microcosm study, we evaluated the impacts of a 24‐h pulse exposure of one of three current‐use insecticides, namely pirimicarb, indoxacarb, and thiacloprid, at two environmentally realistic concentration levels on the larval development and emergence of the nonbiting midge Chironomus riparius. In addition, we measured insecticide concentrations in the larvae and adults using ultrahigh performance liquid chromatography coupled to tandem mass spectrometry by electrospray ionization. Exposure to pirimicarb delayed larval development and emergence, and exposure to indoxacarb reduced emergence success. The neonicotinoid thiacloprid had the greatest impact by reducing larval survival and emergence success. At the same time, thiacloprid was the only insecticide measured in the adults with average concentrations of 10.3 and 37.3 ng/g after exposure at 0.1 and 4 µg/L, respectively. In addition, an approximate 30% higher survival to emergence after exposure to 0.1 µg/L relative to a 4‐µg/L exposure resulted in a relatively higher flux of thiacloprid, from the aquatic to the terrestrial environment, at the lower exposure. Our experimental results help to explain the impacts of current‐use insecticides on aquatic–terrestrial subsidy coupling and indicate the potential for widespread dietary exposure of terrestrial insectivores preying on emerging aquatic insects to the neonicotinoid thiacloprid. Environ Toxicol Chem 2023;42:60–70. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Emergent aquatic insects constitute an important food source for higher trophic levels, linking aquatic to terrestrial ecosystems. Little is known about how land use affects the biomass or composition of insect emergence. Previous studies are limited to individual time points or seasons, hampering understanding of annual biomass export patterns and detection of phenological changes. Over 1 year's primary emergence period, we continuously determined the biomass, abundance, and identity of >45,000 aquatic insects and recorded land‐use‐related environmental variables in 20 stream sites using a paired design with upstream forested sites and downstream agricultural sites. Total insect biomass and abundance were 2–7 mg day−1 m−2 and 7–36 ind day−1 m−2 higher in agricultural than forested sites. However, we found turnover of families between forested and agricultural sites, with more insects with shorter generation time in agriculture, indicating lower sensitivity to land‐use‐related stress because of higher recovery potential. Except for stoneflies, biomass and abundance of major orders were higher in agriculture, but their phenology differed. For different orders, emergence peaked 30 days earlier to 51 days later in agriculture than forest, whereas total abundance and biomass both peaked earlier in agriculture: 3–5 and 3–19 days, respectively. The most important land‐use‐related drivers were pesticide toxicity and electrical conductivity, which were differentially associated with different aquatic insect order abundances and biomass. Overall, we found that land use was related to changes in composition and phenology of aquatic insect emergence, which is likely to affect food‐web dynamics in a cross‐ecosystem context. [ABSTRACT FROM AUTHOR]

Simple Summary: Spodoptera frugiperda is an important agricultural pest of several plants; therefore, a reliable method is required for predicting its emergence in fields. Temperature-dependent development and thermal bio parameters are among approaches that are commonly used to model insect phenology. However, information regarding S. frugiperda is limited. In this study, we evaluated the fitness of S. frugiperda at various constant temperatures. The results of this study indicated that a temperature range of 28–30 °C was optimal for the fitness of S. frugiperda. Among the seven models evaluated in this study, the Shi model best described the relationship between temperature and the development rate of S. frugiperda. Estimating thermal thresholds and selecting appropriate models are crucial for effective decision-making regarding S. frugiperda control. The fall armyworm Spodoptera frugiperda (J.E. Smith) is an economically important pest that recently invaded Africa and Asia; however, information regarding its biological capacity to establish itself in newly invaded environments is largely unknown. We investigated the effects of temperature on the development and survival of the invaded populations of S. frugiperda and selected mathematical models to evaluate its development in a new environment. S. frugiperda exhibited optimum survival and growth at temperatures between 28 °C and 30 °C. The lower and upper thermal thresholds for the egg-to-adult life cycle were 13.51 °C and 34.13 °C, respectively. We compared seven mathematical models and found that the Shi model was the most suitable for describing the temperature-dependent development rate of S. frugiperda. Therefore, the Shi mathematical model may be used to predict both the occurrence of particular developmental stages and the geographic distribution to implement measures for the management of S. frugiperda in agricultural fields. [ABSTRACT FROM AUTHOR]

In Mazagran, Mostaganem Province, Algeria, the seasonal variation in abundance of the scale insects (Hemiptera: Coccomorpha) Coccus hesperidum LINNAEUS, 1758 (Coccidae) and Icerya purchasi MASKELL, 1879 (Monophlebidae) was studied in an orchard on two host plant species, orange (Citrus sinensis) and lemon (C. limon) between December 2018 and November 2019. Every ten days, samples of leaves were collected for monitoring insect numbers. In C. hesperidum on orange and lemon trees respectively, there were three or four population peaks annually (P<0.0001). In I. purchasi, there were three generations annually (P<0.0001). In both scale insect species their abundance was correlated with temperature (P<0.0001 for C. hesperidum, and P=0.010 for I. purchasi) but not with relative humidity levels. Lemon trees had the higher scale insect abundance on 50% of days sampled, for both C. hesperidum and I. purchasi (P<0.005), whereas orange had lower numbers of both scale species. C. hesperidum and I. purchasi occurred on all three sample plots; numbers of both species (particularly C. hesperidum) showed a positive relationship with wind speed (P<0.0001 and P=0.002, respectively), as strong winds probably picked up and carried crawlers into the sample plots situated downwind. [ABSTRACT FROM AUTHOR]

Trematodes of the genus Plagiorchis are widespread endoparasites with a life cycle involving several hosts. The second intermediate hosts of the trematodes of genus Plagiorchis are studied for the first time in the basin of Lake Chany in the forest-steppe zone of Western Siberia, which is crossed by the migration way of many species of aquatic and near-water birds—final hosts of these trematodes. This study was conducted in 2014–2015 in the reed beds of Lake Fadikha, which is a habitat of the first intermediate hosts of plagiorchiids: snails. Invertebrates from classes Insecta, Malacostraca, and Gastropoda, as possible second intermediate hosts of the Plagiorchiidae trematodes, are studied for the prevalence and intensity of trematode infection. Metacercariae (larvae inhabiting the second intermediate hosts) of genus Plagiorchis (P. elegans and P. multiglandularis) are found only in the insects from order Odonata. The largest portion among infected larvae is comprised of larvae of Sympetrum vulgatum (68%), followed by S. flaveolum (18%), S. sanguineum (9%), and Aeshna serrata (5%). The prevalence of the metacercariae of the detected trematode species for the four Odonata species during the study years varied from 3.3 to 45.5%; the intensity of infection varied from 2 to 4 trematodes per 1 odonate larva. Infection with metacercariae increases with the age of odonate larvae. A trend towards a positive correlation between the infection (prevalence) of the first (snails) and the second (odonate larvae) intermediate hosts is identified. A significant relationship is identified between the prevalence of metacercariae of the odonate larvae and their population density, which varies throughout the season. Seasonal changes in the infection of odonates with metacercariae of the trematodes of genus Plagiorchis are associated with the phenology of these insects. Periods of increased infection are registered just prior to the mass emergence of odonates, when the abundance of odonate larvae in the water body is the highest, and vice versa, periods of decline in infection are registered after the mass metamorphosis of odonates. [ABSTRACT FROM AUTHOR]

Forest insect pest phenology and infestation pressure may shift as temperatures continue to warm due to climate change, resulting in greater challenges for sustainable forest management. The Nantucket pine tip moth (NPTM) (Rhyacionia frustrana Comstock) (Lepidoptera: Tortricidae) is a native forest regeneration pest in the southeastern U.S. with multiple generations per year. Changes in NPTM voltinism may result from temperature-induced shifts in NPTM phenology. Degree-day models have been used to develop optimal spray dates (OSDs) for NPTM. The 2000 Spray Timing Model (STM), based on temperature data from 1960 to 2000, provided generation-specific 5-d OSDs to effectively time applications of contact insecticides. An updated degree-day model, the 2019 STM, is based on temperature data from 2000 to 2019 and was used to detect changes in voltinism as well as shifts in phenology and OSDs. Based on the model, increased voltinism occurred at 6 of the 28 study locations (21%). Changes in voltinism occurred in the Piedmont and Coastal Plain of Georgia, U.S. with shifts from three to four or four to five generations a year, depending on location. The OSDs from the 2019 STM were compared to the 2000 STM OSDs. Over half (57%) of the OSDs differed by 5–15 d, with the majority (66%) resulting in earlier spray dates. The 2019 STM will help growers adapt NPTM control tactics to temperature-induced phenology shifts. NPTM serves as an example of temperature-induced changes attributed to climate change in a forest insect pest with important implications to forest management. [ABSTRACT FROM AUTHOR]

Insect phenology consists of the timing of life events, as well as the number of generations (voltinism). While several studies have focused on the impact of climate on the timing of seasonal events, or the voltinism of single species, we have few insights into the factors that shape patterns of voltinism within ecological communities. Importantly, voltinism can have a major impact on population growth, species interactions, and rate of evolution.We investigated the relative importance of spatial variation in temperature and species traits in shaping patterns of voltinism within an herbivore community feeding on deciduous oaks across a temperature gradient in Europe.Voltinism increased with temperature, where the probability for a species to be univoltine decreased with temperature, whereas the probability for a species to be strictly multivoltine increased with temperature. The relative abundance of the first and subsequent generations of multivoltine species did not significantly change along the temperature gradient. Resource specialisation affected voltinism, where oligophagous and polyphagous species were more likely to be strictly multivoltine than narrow oligophagous species. Overwintering stage and body size did not affect voltinism, and there was no evidence that species traits influenced the relationship between temperature and voltinism.Our findings highlight that temperature and species traits shape variation in voltinism within an herbivore community associated with oak trees. These temperature‐induced shifts in voltinism within the oak‐associated herbivore community may have profound effects on the synchrony within and between trophic levels, and consequently for food web structure and outbreak dynamics. [ABSTRACT FROM AUTHOR]

Climate change may disrupt species–species interactions via phenological changes in one or both species. To predict and evaluate the influence of climate change on these interactions, long-term monitoring and sampling over large spatial areas are required; however, funding and labor constraints limit data collection. In this study, we predict and evaluate the plant–insect interactions with limited data sets. We examined plant–insect interaction using observational data for development of the crop plant rice (Oryza sativa) and an effective accumulated temperature (EAT) model of two mirid bugs (Stenotus rubrovittatus and Trigonotylus caelestialium). We combined 11 years of records monitoring rice phenology and the predicted phenology of mirid bugs using spatially–explicit EAT models based on both spatially and temporally high resolutions temperature data sets, then evaluated their accuracy using actual pest damage records. Our results showed that the predicted interactions between rice and mirid bugs explained rice damage to some degree. Our approach may apply predicting changes to plant–insect interactions under climate change. As such, combining plant monitoring records and theoretical predictions of insect phenology may be effective for predicting species–species interactions when available data are limited. [ABSTRACT FROM AUTHOR]

Although corn production is affected by several harmful insects, its most important pest in the southeastern region of Europe is the European corn borer (ECB), Ostrinia nubilalis Hübner, 1796 (Lepidoptera: Pyralidae). Chemical control of O. nubilalis remains the main strategy in conventional corn production. The key to successfully achieving a high efficiency of insecticides is determining the appropriate moment of application, including the exact time in the insect’s life cycle when it is most vulnerable. In this study, monitoring data on the flight dynamics of ECB adults from a seven-year period (2014–2020) were exploited for the development of a predictive model of adult numbers within the growing season. ECB monitoring was performed by using light traps at 15 different locations in the Vojvodina region (Serbia) during the specified time period. First, the calendar for Vojvodina was created based on the analytics of the collected monitoring data. Additionally, the calendar was converted to the probability of ECB occurrence during the growing season, specifying the time interval between the appearance of each generation of the pest. Second, using machine learning techniques, a phenological model was designed that included daily values of relevant meteorological features, such as cumulative degree-days, relative humidity, and precipitation. The calendar had a lower prediction error when compared to the phenological model, and it was tested as a supporting management tool for the ECB in 2021, with a root-mean-square error of the number of adults of 46.67. Such an approach could significantly reduce both the consumption of insecticides and the number of chemical treatments, respectively. Above all, this approach has broad potential in IPM and organic farming, and it is fully compatible with biological control methods.

Although climate-driven phenological shifts have been documented for many taxa across the globe, we still lack knowledge of the consequences they have on populations. Here, we used a comprehensive database comprising 553 populations of 51 species of north-western Mediterranean butterflies to investigate the relationship between phenology and population trends in a 26-year period. Phenological trends and sensitivity to climate, along with various species traits, were used to predict abundance trends. Key ecological traits accounted for a general decline of more than half of the species, most of which, surprisingly, did not change their phenology under a climate warming scenario. However, this was related to the regional cooling in a short temporal window that includes late winter and early spring, during which most species concentrate their development. Finally, we demonstrate that phenological sensitivity—but not phenological trends—predicted population trends, and argue that species that best adjust their phenology to inter-annual climate variability are more likely to maintain a synchronization with trophic resources, thereby mitigating possible negative effects of climate change. Our results reflect the importance of assessing not only species' trends over time but also species' abilities to respond to a changing climate based on their sensitivity to temperature. [ABSTRACT FROM AUTHOR]

Simple Summary: The most important honeydew-producing insect in Greece is Marchalina hellenica (Coccoidea: Marchalinidae), which is a parasite on pine trees. The current work is part of an ongoing research project aiming to provide knowledge on honeydew-producing insects and the impact of critical factors (climate, beekeeping manipulations, honeydew-producing insect phenology) on honeydew honey production. Empirical evidence indicates that among the weather factors, the most important one, at least for spring honeydew secretions, appears to be temperature and, more specifically, the existence of cold winter days. Presently, we investigate the effect of cold periods in February on the life cycle of Marchalina hellenica. Our primary goal is to help beekeepers plan the timely exploitation of honeydew secretions of pine trees. Such a potential will be beneficial for beekeepers, the rural economy, and forest protection. It should be noted that current results highlight the impact of climate change in the field of entomology, and they indicate that the life cycle of Marchalina hellenica is expected to be drastically shorter. Climate change is considered a major factor affecting honeybees' behavior and productivity with major consequences in both honey and agricultural production. Many research studies have expressed serious concerns about the mass losses of bee colonies and the role of bees as pollinators, while others have underlined important issues for the impact of the increase in temperature on honeybee abundance and honey yields. In the present work, we draw our attention to Marchalina hellenica, which is the most important honeydew-producing insect in Greece. A statistically significant forecasting model for the effect of cold periods in February on the life cycle of the insect is constructed, with the aid of the Cumulative Logit Model and the theory of runs. The forecasting model may help beekeepers plan the timely exploitation of honeydew secretions of pine trees, which will be beneficial for beekeepers, the rural economy, and forest protection. The new suggested model also indicates that, in view of the climate change scenarios seen in the literature, the life cycle of M. hellenica is expected to be drastically shorter. [ABSTRACT FROM AUTHOR]

Four species of the genus Zabrachypus were collected and identified from northern Iran, of which one species is recorded for the first time, Z. cazorlensis Rey del Castillo, 1996, and two species are described as new: Z. rubroabdominalis n. sp. and Z. rugatus n. sp.. A key to the species is provided. Their ecology and phenology are discussed. [ABSTRACT FROM AUTHOR]

Insect phenology is highly temperature-dependent. Higher temperatures can lead to earlier emergence and lengthening of the active period, which enable many insect groups to complete more generations. Studies on the effects of climate change on insect populations are providing concerning evidence supporting this relationship. These kind of shifts in phenology and voltinism also occur in agricultural and forest insect pests and their natural enemies, with potential implications for biological control. The consequences derived from changing temperature regimes on tritrophic interactions remain poorly studied, particularly in gall-inducing insects and their parasitoids. Here we detail the occurrence of bivoltinism in the exotic parasitoid Torymus sinensis, previously categorized as univoltine, a widely introduced species to fight against the invasive Asian chestnut gall wasp Dryocosmus kuriphilus wherever this pest spread. This plasticity in voltinism has been observed in the southernmost European distribution of D. kuriphilus, and appears to be mediated by both temperature and gall traits, namely size or the number of gall chambers. Bivoltinism was most common at annual mean temperatures around 13.5°C and in galls with more chambers. Through this work, we intend to unravel the factors behind this phenomenon and discern the possible consequences on host-parasitoid interactions.

Studies on temperature-dependent phenology and morphology of insects facilitate examination of the consequences of temperature on their growth, development and population dynamics. The effects of seasonal changes on the life cycle and morphometry of Anisops breddini were studied by rearing eggs to adults under laboratory conditions during the wet and dry seasons. The average incubation period of eggs, developmental durations of instars I–V and total developmental time were significantly less at warm temperature (wet season) than in cold temperature (dry season). However, the hatching percentage was significantly higher at warm temperature than in cold temperature. Morphometric measurements of nymphs and adults were also significantly less at warm temperature than in cold temperature. Laboratory reared individuals during the wet season at warm temperature had faster development and produced smaller individuals as compared with the dry season. The developmental durations and body size of the experimental individuals were significantly negatively correlated with rearing temperature. The study further revealed that in warm temperature the developmental duration of the experimental individuals become shorter which in turn might increase the number of generations of this insect. [ABSTRACT FROM AUTHOR]

Insect phenological lability is key for determining which species will adapt under environmental change. However, little is known about when adult insect activity terminates and overall activity duration. We used community‐science and museum specimen data to investigate the effects of climate and urbanisation on timing of adult insect activity for 101 species varying in life history traits. We found detritivores and species with aquatic larval stages extend activity periods most rapidly in response to increasing regional temperature. Conversely, species with subterranean larval stages have relatively constant durations regardless of regional temperature. Species extended their period of adult activity similarly in warmer conditions regardless of voltinism classification. Longer adult durations may represent a general response to warming, but voltinism data in subtropical environments are likely underreported. This effort provides a framework to address the drivers of adult insect phenology at continental scales and a basis for predicting species response to environmental change. [ABSTRACT FROM AUTHOR]

Climate change is advancing the onset of phenological events, with the rate of advance varying among species and trophic levels. In addition, local populations of the same species may show genetic differences in their response to seasonal cues. If populations of interacting species differ in their response, then climate change may result in geographically varying shifts in the community‐level distribution of interaction strength. We explored the magnitude of trophic‐ and species‐level responses to temperature in a tritrophic system comprising pedunculate oak, insect herbivores, and their associated parasitoids. We sampled local realizations of this community at five sites along a transect spanning fifteen degrees of latitude. Samples from each trophic level at each site were exposed to the same set of five climatic regimes during overwintering in climate chambers. We then recorded the number of days and degree‐days required for oak acorns to develop and insects to emerge. In terms of dates of events, phenology differed among populations. In terms of degree‐days, we found that for two species pairs, the heat sum required to develop in spring differed by an additional ˜500 degree‐days between trophic levels when overwintering at the highest temperature. For three species, within‐population variation in the number of degree‐days required for emergence was higher at warmer temperatures. Our findings suggest that changing temperatures can modify interactions within a community by altering the relative phenology of interacting species and that some interactions are more vulnerable than others to a shift in temperature. The geographic variation in the phenological response of a species suggests that there is a genetic component in determining the phenology of local populations. Such local variation blended with interspecific differences in responses makes it complex to understand how communities will respond to warmer temperatures. [ABSTRACT FROM AUTHOR]

Spatiotemporal variation in forage is a primary driver of ungulate behavior, yet little is known about the nutritional components they select, and how selection varies across the growing season with changes in forage quality and quantity. We addressed these uncertainties in barren‐ground caribou (Rangifer tarandus), which experience their most important foraging opportunities during the short Arctic summer. Recent declines in Arctic caribou populations have raised concerns about the influence of climate change on summer foraging opportunities, given shifting vegetation conditions and insect harassment, and their potential effects on caribou body condition and demography. We examined Arctic caribou selection of summer forage by pairing locations from females in the Central Arctic Herd of Alaska with spatiotemporal predictions of biomass, digestible nitrogen (DN), and digestible energy (DE). We then assessed selection for these nutritional components across the growing season at landscape and patch scales, and determined whether foraging opportunities were constrained by insect harassment. During early summer, at the landscape scale, caribou selected for intermediate biomass and high DN and DE, following expectations of the forage maturation hypothesis. At the patch scale, however, caribou selected for high values of all forage components, particularly DN, suggesting that protein may be limiting. During late summer, after DN declined below the threshold for protein gain, caribou exhibited a switch at both spatial scales, selecting for higher biomass, likely enabling mass and fat deposition. Mosquito activity strongly altered caribou selection of forage and increased their movement rates, while oestrid fly activity had little influence. Our results demonstrate that early and late summer periods afford Arctic caribou distinct foraging opportunities, as they prioritize quality earlier in the summer and quantity later. Climate change may further constrain caribou access to DN as earlier, warmer Arctic summers may be associated with reduced DN and increased mosquito harassment. [ABSTRACT FROM AUTHOR]

Brinjal shoot and fruit borer (BSFB) Leucinodes orbonalis Guenee is a key pest of brinjal and a major constraint to its production in the Indian subcontinent. The influence of constant as well as alternating temperatures on the development and survival of the pest is not known. Also, no information is available on the thermal constant, development thresholds, and phenology for the insect. So, the development and survival of Leucinodes orbonalis were studied under laboratory conditions at five constant (15 ± 1, 20 ± 1, 25 ± 1, 30 ± 1 and 35 ± 1 °C) and six alternating temperatures (25:15, 30:15, 35:15, 25:20, 30:20 and 35:20 °C) with 70 ± 5% R.H. and photoperiod of 14:10 (L:D) h. Under the alternating temperature regimes, maximum and minimum temperatures were maintained in a cycle of 14 and 10 h, respectively. Transition from maximum to minimum temperature followed square waveform and was complete within 10 min. The rate of development of the egg, larval, pupal, and adult stages accelerated with increases in the levels of temperature. Survival of BSFB was highest at intermediate temperature levels (25-30 °C), and it started declining outside this range. The favourable range of constant temperature for the development from egg to adult stage was 20 ± 1–35 ± 1 °C, while all six alternating temperatures were conducive for complete development of the pest. The thermal constant (K) and lower developmental threshold (Tmin) determined from a linear regression analysis for the total development period were 435.39–530.66 DD and 5.69–14.63 °C, respectively. The non-linear models did not fit the data obtained from constant temperature studies, as they overestimated the temperature threshold for the pest. In the case of alternating temperatures, Tmin, Topt, and Tmax for the different developmental stages were in the range of 6.87–10.47 °C, 30.3–30.4 °C, and 41.96–42.31 °C, under Briere-1, Briere-2 and Kontodimas models. Our results provide a framework for forecasting the pest incidence in the field, thus helping in modulating management schedules and techniques to target the weak link in the life cycle of the pest. [ABSTRACT FROM AUTHOR]

Understanding the genetic architecture of life history plasticity may inform resilience under environmental change, but relatively little is known for the inhabitants of unpredictable wet‐dry tropical environments. Here, I explore the quantitative genetics of juvenile growth and development relative to hostplant phenology in the butterfly Eurema hecabe. Wet season generations of this species breed explosively on leguminous annuals whereas dry season generations subsist at low density upon an alternative perennial host. The wet‐to‐dry season transition is temporally unpredictable and marked by widespread host defoliation, forcing a large cohort of stranded larvae to either pupate prematurely or prolong development in the hope of renewed foliage production. A split‐brood experiment demonstrated greater performance on high quality annual as opposed to perennial host foliage and a marked decline under the stressed conditions faced by stranded wet season larvae. Genetic variances for rates of growth and development were equivalent among high quality treatments but strikingly elevated under resource stress, and the associated cross‐environment genetic correlations were indistinguishable from zero. The results demonstrate genotype‐environment interaction involving both rank order and variance scale, thereby revealing genetic variance for norms of reaction that may reflect variable risk aversion given an unpredictable tropical host phenology. [ABSTRACT FROM AUTHOR]

As the climate changes, mismatches in phenology between predator and prey species may become more common. For example, many songbirds rely on short peaks in insect and fruit production at stopover sites during migration. Previous research indicates that migratory songbirds are able to modify their departure and arrival dates to some extent despite their reliance on more stable cues such as photoperiod and more stable endogenous factors. However, insect and plant phenology may shift more rapidly with changing climate, reducing foraging opportunities along migratory routes. To quantify changes in songbird arrival patterns at stopover sites during fall migration we analyzed forty years of banding data in nine passerine species commonly captured at banding stations in southwestern Michigan. Weather data revealed that the region has warmed by nearly 2° (C) over this timeframe. For each species, we assessed annual trends in arrival date and temperature at arrival. To determine whether arrival trends impacted stopover site function we also quantified trends in site use and morning mass gain. Arrival dates advanced significantly in three species, and were delayed significantly in three other species. However, air temperature at arrival increased significantly over time for all nine study species. Over the same time period, site use and the pattern of morning mass gain remained stable or increased for all species. Despite the changing climate and the resulting increase in temperature at arrival for migrants, our data indicate that these stopover locations continue to function as a refueling sites. Nonetheless, we must be wary of thresholds and ecological mismatches that may occur if warming trends continue. [ABSTRACT FROM AUTHOR]

Higher temperatures and drought are key aspects of global change with the potential to alter the distribution and severity of many arthropod pests in forest systems. Scale insects (Hemiptera: Coccoidea) infest many tree species and are among the most important pests of trees in urban and rural forests, plantations and other forest systems. Infestations of native or exotic scale insects can kill or sicken trees with economic and ecosystem-wide consequences. Warming can have direct effects on the life history, fitness and population dynamics of many scale insect species by increasing development rate, survival or fecundity. These direct benefits can increase the geographic distribution of scale insects and their consequences for tree health. Warming and drought can affect scale insects indirectly by altering the quality of their host trees. Additive or interactive effects of warming and drought can change tree quality in such a way that it increases scale insect fitness and population growth. However, the effects are species- and context-dependent with some scale insect species negatively affected by drought-induced changes in tree quality. Warming and drought are often coincident in urban forests and predicted to co-occur in many parts of the world under climate change scenarios. The individual and interactive effects of these factors require further research to inform predictions and management of scale insect pests. Warming also indirectly affects scale insects by altering interactions with natural enemies. This includes changes in natural enemy phenology, community composition and abundance. In addition, warming can alter scale insect phenology or voltinism causing asynchrony with natural enemies or population growth too rapid for natural enemies to suppress. Direct and indirect effects of warming and drought on scale insects can increase the potential for some exotic species to become established and for some native species to become invasive. Unfortunately, much research on scale insects is confined to a few particularly important native or exotic pests which limits our ability to predict the effects of warming on many current or potential pests. More research is required to understand how warming and drought affect scale insects, scale insect management and the forest systems they inhabit. [ABSTRACT FROM AUTHOR]

Summary: Plant–herbivore interactions have evolved in response to coevolutionary dynamics, along with selection driven by abiotic conditions. We examine how abiotic factors influence trait expression in both plants and herbivores to evaluate how climate change will alter this long‐standing interaction. The paleontological record documents increased herbivory during periods of global warming in the deep past. In phylogenetically corrected meta‐analyses, we find that elevated temperatures, CO2 concentrations, drought stress and nutrient conditions directly and indirectly induce greater food consumption by herbivores. Additionally, elevated CO2 delays herbivore development, but increased temperatures accelerate development. For annual plants, higher temperatures, CO2 and drought stress increase foliar herbivory. Our meta‐analysis also suggests that greater temperatures and drought may heighten florivory in perennials. Human actions are causing concurrent shifts in CO2, temperature, precipitation regimes and nitrogen deposition, yet few studies evaluate interactions among these changing conditions. We call for additional multifactorial studies that simultaneously manipulate multiple climatic factors, which will enable us to generate more robust predictions of how climate change could disrupt plant–herbivore interactions. Finally, we consider how shifts in insect and plant phenology and distribution patterns could lead to ecological mismatches, and how these changes may drive future adaptation and coevolution between interacting species. [ABSTRACT FROM AUTHOR]

Phenological change is the most widely documented biological impact of climate change, but shows marked variation in magnitude among populations and species. Thus, quantifying the environmental factors and organismal differences driving this intra‐ and interspecific variability in phenology is vital to understand and forecast the ecological consequences of climate change.Here, we test intra‐ and interspecific differences for a set of butterfly species in the organismal sensitivity of flight phenology and its dependence on environmental factors, using as our model system an elevation gradient in a Mediterranean mountain range where temperature and relative humidity vary substantially over space and time.We use field‐collected meteorological data, and butterfly counts for 20 univoltine species over 14 years, to test the relative effects on phenology of temperature and relative humidity, the sensitivity of phenology to spatial and temporal variation in temperature and whether ecological traits account for inter‐specific variation in sensitivity.For all species, temperature in the months immediately preceding adult emergence had the strongest relationship with phenology. All species appeared earlier in warmer years, with those flying earlier in the season showing the greatest sensitivity to annual (temporal) variation in temperature. However, only a minority of species showed evidence of plastic, space‐for‐time responses to temperature. Instead, most species showed strong evidence that phenology was more sensitive to temporal than spatial variation in temperature.Our results support the dominant influence of temperature on phenology, even in Mediterranean environments suffering summer drought. They also suggest that accurate forecasts of species' phenological shifts could require the isolation of spatial from temporal components of temperature variation, because the sensitivity of populations and species may differ across these two dimensions. The factors driving synchronisation of phenology over space merit particular research in the context of climate change, given their potential to expose populations simultaneously to environmental extremes. [ABSTRACT FROM AUTHOR]