Moth Abundance Research Articles

Moths versus Bees: Contrasts in Habitat Preferences Across Barrens of the Northeastern USA.

Bees and moths are globally important pollinators. Xeric barrens in the largely mesic northeastern USA support high levels of pollinator diversity, including rare bees and moths. We investigated the response of bee vs. moth communities to abiotic and vegetation drivers in barrens across the region. We sampled local environmental conditions, vegetation, bees, and moths for 2-4 years in 19 preserves. Employing random forest analysis, we tested the role of 29 abiotic and vegetation predictors of bee vs. moth abundance, species richness, Shannon-Wiener Index, evenness, and species composition. Variables related to climate, canopy cover, and soils were the most important predictors of abundance, diversity, and species composition for both bees and moths. Vegetation variables, such as species richness of shrubs and hostplants, were also important for bees. The direction of these relationships contrasted sharply between bees and moths: bees were more abundant and species rich in more open, sandy sites and moths the opposite. Habitat preferences for a subset of moth xeric specialists were much more similar to bees than to other moths, with a preference for open, sandy conditions. Contrasts between bees and moths in habitat preferences likely stemmed from differences in their life histories: bees rely on flowers for feeding and porous substrates for nesting, whereas most moth adults feed on flowers, but many moth caterpillars use woody plants as hosts. In sharp contrast to the results for abundance and richness, bees and moths responded similarly for the Shannon-Wiener Index, which raises important general questions about the conservation value of these two metrics. Our results suggest that, because of differences in habitat preferences among pollinators, barrens management for both open and more closed habitats is likely to promote the highest abundance and diversity of local bee and moth pollinator communities jointly.

A Phenomenon: What Are the Minuscule Grey Moths Abundant in the Dry Season in the Tropical Dry Forests of the Pacific Coast of Honduras?

Our investigation centered on the tropical dry forests along the Pacific coast of Honduras, aiming to elucidate the presence and abundance of minuscule grey moths during the dry season. Through specimen dissections and the taxonomic identification of the collected material, we have described three new species: Acalyptris podenasi sp. nov., A. palpiformis sp. nov., and A. tortoris sp. nov. Additionally, we documented two species previously known from neighboring countries, A. lascuevella Puplesis & Robinson and A. basicornis Remeikis & Stonis. The females of A. lascuevella were previously unknown and are documented here for the first time. Morphological examinations were complemented by DNA barcoding, particularly highlighting variation in A. lascuevella. The paper's primary significance lies not only in the description of new species but also in uncovering their taxonomic, morphological, and molecular importance. We found that these species are unique and indicative of the previously unstudied dry forests as a distinct ecosystem. Our findings revealed several novel atypical morphological traits within the studied Nepticulidae, including unusually large signum cells in the female genitalia, a dorso-ventrally divided uncus, and asymmetrical valvae in the male genitalia. These discoveries underscore the morphological diversity of Acalyptris Meyrick and their significance in evolutionary biology. Consequently, the paper addresses a previously unknown phenomenon of the occurrence and astonishing abundance of minuscule plant-mining micromoths in dry deciduous forests during the peak of the dry season. We hope that this paper will encourage Lepidoptera taxonomists to explore micromoths in other tropical dry forests, which, while limited in distribution, hold global importance. The paper is extensively illustrated with photographs of Acalyptris adults and their genitalia, along with maps, habitats, and molecular phylogenetic trees.

Moths respond to key habitat structures in conifer plantations managed as irregular high forest

Conifer plantations need to deliver greater multi-functionality beyond the production of timber. This includes the support of biodiversity and associated ecosystem functioning. Forest managers are increasingly adopting novel, more sustainable forest management techniques such as irregular silviculture, a type of continuous cover forestry, to manage plantations, in response to climate change. This may confer benefits to important elements of woodland biodiversity such as moths, by creating plantations that have diverse vertical structure and a permanent canopy (called irregular high forest). In this study at two estates in south-west Britain we specifically tested whether moth species richness and abundance (at the guild and overall level) were associated with (1) surrounding land cover types and (2) habitat structures within stands undergoing transformation using irregular silviculture. A total of 268 species of 11,582 individuals were recorded. Moths responded to all four landscape cover types, negatively to arable and conifer woodland, positively for broadleaf woodland, and both positively and negatively for improved grassland. Moth richness and abundance had a positive association with basal area (albeit below standard even aged stocking rates with most plots around 40–45 m2ha) and a weak positive association with higher vertical structural complexity (indicated by a more developed understorey and sub-canopy layers). Moth abundance had a moderate positive association with broadleaf canopy where we recommend plantations should have at least 10–15 % broadleaf canopy cover. Moth richness and abundance were negatively associated to mean tree diameter and canopy openness. Many of these features are more prevalent in stands further progressed towards irregular high forest. We show how moth communities can be maintained via more sustainable forestry management techniques that increase overall habitat and structural complexity.

On the mass infection of the pine moth pupae by the eulophid parasitoid wasp Aprostocetus xanthopus (Hymenoptera, Chalcidoidea) in Voronezh oblast

In the outbreak of the pine moth Dendrolimus pini (Linnaeus, 1758) (Lepidoptera, Lasiocampidae) in Voronezh Oblast, mass infection of its pupae with the pupal parasitoid wasp, Aprostocetus xanthopus Nees, 1834 (Hymenoptera, Eulophidae), was revealed. It had destroyed from 7 to 25% of all phytophage pupae, which indicates its significant impact on the cocoon moth abundance. Previously, this parasitoid was frequently noted as an entomophage of the pine moth, but it has always been low in number. The biology of A. xanthopus has not been studied enough completely and this hampers its use as an agent of biological protection of pine forests from the pine moth.

Species spectrum and abundance of moths (Lepidoptera) in the greenhouse culture of Solanum lycopersicum

Species spectrum and abundance of moths (Lepidoptera) in the greenhouse culture of Solanum lycopersicum

Urban environment decreases pollinator availability, fertility, and prolongs anthesis in the field bindweed (Convolvulus arvensis Linnaeus, 1753)

ABSTRACT Urbanization alters the natural environment, with broad negative impacts on living organisms. Urbanization can also disrupt plant-pollinator networks by reducing the abundance and diversity of invertebrates. Firstly, I investigated whether the field bindweed (Convolvulus arvensis) is an obligatory entomophilous plant because previous reports were ambiguous. Secondly, I investigated how the obligatory entomophilous plant, field bindweed, responds to urbanization by comparing the flowering duration (anthesis) and the reproductive success of field bindweeds in urban and rural populations. Unlike cross-pollinated flowers and controls, flowers experimentally prevented from pollination and self-pollinated flowers did not produce seeds, suggesting that the field bindweed is self-incompatible and obligatory entomophilous. The abundance of urban pollinators was 5–6 times lower than the abundance of rural pollinators, and flies (Diptera), beetles (Coleoptera) and moths (Lepidoptera) were significantly more negatively influenced by the urban environment than hymenopterans (Hymenoptera). Urban plants showed significantly longer anthesis duration and lower reproductive success than rural plants. Illuminance and low pollinator abundance were negatively associated with the duration of the anthesis, but relative humidity did not affect the anthesis. Prolonged duration of the anthesis may be an adaptation to pollinator scarcity because more prolonged flowering increases the likelihood of pollination. Future research should unravel whether the longer anthesis of urban flowers is determined by behavioral plasticity or by the evolutionary selection of plants with a genetically determined longer anthesis.

Changes in Relative Abundance of Giant Silkworm and Royal Moths (Saturniidae) in Megalopolises, with Special Reference to Antheraea polyphemus

Changes in Relative Abundance of Giant Silkworm and Royal Moths (Saturniidae) in Megalopolises, with Special Reference to Antheraea polyphemus

Disentangling how urbanisation influences moth diversity in grasslands

Abstract Urban areas have profound impacts on local species diversity and composition through a set of intertwined changes in the environment. As the world is rapidly urbanising while simultaneously facing a biodiversity crisis, a better understanding of how urbanisation influences biodiversity is necessary. To test if and how urbanisation influences moth diversity and whether urbanisation is acting directly or indirectly via urbanisation‐induced increased habitat isolation, smaller habitat area, higher light pollution and increased mowing intensity, we sampled moths with light trapping in 20 grasslands in the urban core of the city of Darmstadt (southwestern Germany) and 20 grasslands in the surrounding area. Moth abundance and diversity decreased with increasing urbanisation. Smaller habitat area and high mowing intensity reduced moth abundance, while other environmental variables including isolation and light pollution had only indirect effects. High levels of urbanisation were associated with reduced moth abundance, which in turn drove declines in diversity. Urbanised sites favoured generalist species and differed in species composition compared to sites in the surrounding. The results show that urbanisation is directly reducing moth abundance and diversity in cities. The negative effect of urbanisation is further attenuated by habitat fragmentation and high mowing intensity, which are both known drivers of biodiversity decline in urban areas and beyond. While urbanisation itself is often irreversible, reducing mowing intensity and preserving larger grassland areas could facilitate moths and other taxa in and around cities.

Substantial urbanization-driven declines of larval and adult moths in a subtropical environment.

Recent work has shown the decline of insect abundance, diversity and biomass, with potential implications for ecosystem services. These declines are especially pronounced in regions with high human activity, and urbanization is emerging as a significant contributing factor. However, the scale of these declines and the traits that determine variation in species-specific responses remain less well understood, especially in subtropical and tropical regions, where insect diversity is high and urban footprints are rapidly expanding. Here, we surveyed moths across an entire year in protected forested sites across an urbanization gradient to test how caterpillar and adult life stages of subtropical moths (Lepidoptera) are impacted by urbanization. Specifically, we assess how urban development affects the total biomass of caterpillars, abundance of adult moths and quantify how richness and phylogenetic diversity of macro-moths are impacted by urban development. Additionally, we explore how life-history traits condition species' responses to urban development. At the community level, we find that urban development decreases caterpillar biomass and adult moth abundance. We also find sharp declines of adult macro-moths in response to urban development across the phylogeny, leading to a decrease in species richness and phylogenetic diversity in more urban sites. Finally, our study found that smaller macro-moths are less impacted by urban development than larger macro-moths in subtropical environments, perhaps highlighting the tradeoffs of metabolic costs of urban heat favoring smaller moths over the relative benefits of dispersal for larger moths. In summary, our research underscores the far-reaching consequences of urbanization on moths and provides compelling evidence that urban forests alone may not be sufficient to safeguard biodiversity in cities.

Expansion of apple cultivation increases the abundance of codling moth (Cydia pomonella) in agricultural landscapes of China.

Agricultural land-use change is an important driver of pest population dynamics, and can alter source-sink dynamics and the concentration-dilution effects of the landscape. Understanding the effects of land use on pests at both landscape and regional levels is essential for the development of sustainable pest management strategies given the large changes occurring in cropping systems in China. At the landscape level, we investigated the impacts of landscape composition and edge density on pheromone trap catch of codling moth (Cydia pomonella) in apple orchards, in Aksu, Xinjiang, China. At the regional scale, we conducted a meta-analysis using data from studies performed across the Aksu area in recent decades, to assess the relationship between trends in codling moth abundance and the area of apple cultivation. Both extensive planting of apple and large areas of annual crops in the landscape increased the abundance of codling moth, whereas the presence of secondary host plants (peach, pear, walnut, plum, and apricot) had a negative effect. Seminatural habitats and landscape edge density did not significantly affect codling moth abundance. The responses of different generations of codling moth to landscape factors were varied. At the regional level, codling moth occurrence was positively correlated with the expansion of apple production areas. Expansion of apple cultivation increases the abundance of codling moth in agricultural landscapes. We recommend decreasing the area devoted to monocultures of apple when designing agricultural landscapes and increasing plantings of secondary host crops to dilute and reduce the abundance of codling moth. © 2024 Society of Chemical Industry.

Population links between an insectivorous bird and moths disentangled through national-scale monitoring data.

Insects are key components of food chains, and monitoring data provides new opportunities to identify trophic relationships at broad spatial and temporal scales. Here, combining two monitoring datasets from Great Britain, we reveal how the population dynamics of the blue tit Cyanistes caeruleus are influenced by the abundance of moths - a core component of their breeding diet. We find that years with increased population growth for blue tits correlate strongly with high moth abundance, but population growth in moths and birds is less well correlated; suggesting moth abundance directly affects bird population change. Next, we identify moths that are important components of blue tit diet, recovering associations to species previously identified as key food sources such as the winter moth Operoptera brumata. Our work provides new evidence that insect abundance impacts bird population dynamics in natural communities and provides insight into spatial diet turnover at a national-scale.

Does artificial light at night alter moth community composition?

Ecological studies investigating the effects of artificial light at night (ALAN) have primarily focused on single or a few species, and seldom on community-level dynamics. As ALAN is a potential cause of insect and biodiversity declines, community-level perspectives are essential. We empirically tested the hypothesis that moth species differentially respond to ALAN and that these responses can cause shifts in community composition. We sampled moths from prairie fragments in Colorado, USA. We tested whether local light sources, sky glow, site area and/or vegetation affected moth community diversity. We found that increased sky glow decreased moth abundance and species richness and shifted community composition. Increased sky glow shifted moth community composition when light and bait traps were combined; notably this result appears to be driven entirely by moths sampled at bait traps, which is an unbiased sampling technique. Our results show that ALAN has significant effects on moth communities and that local light sources have contrasting effects on moth community composition compared to sky glow. It is imperative that we better understand the contrasting effects of types of ALAN to comprehend the overall impacts of light pollution on biodiversity declines. This article is part of the theme issue 'Light pollution in complex ecological systems'.

Seasonal Hyperacute Panuveitis (SHAPU) Outbreak Amidst COVID-19 Pandemic

ABSTRACT Purpose To document the demographic profile of the SHAPU outbreak amidst the COVID-19 pandemic. Methods A multicentric cross-sectional study of the 2021 SHAPU outbreak during the second phase of the COVID-19 outbreak. Results A total of 135 patients were diagnosed with SHAPU from August to December 2021, 77 (57%) were children <16 years, males 54.8% and 34.8% had direct physical contact with white moths and 41.5% had severe type of SHAPU. Dramatic increment in the moth abundance was noted in these outbreak sites. Few cases presented with atypical ocular findings, unlike past outbreaks. Due to the ongoing COVID-19 pandemic with restrictions on travel and transportation, timely management was difficult and good visual outcome was achieved only in mild-moderate cases with an early presentation. Conclusion The surge in the number of SHAPU patients, its occurrence in areas previously unreported, and some atypical presentation added raised suspicion of a possible link between COVID-19 and SHAPU.

Towards reliable estimates of abundance trends using automated non‐lethal moth traps

Abstract Monitoring insect abundance or species richness at high spatial and temporal resolution is difficult due to personnel, maintenance, and post‐processing costs as well as ethical considerations. Non‐invasive automated insect monitoring systems could provide a solution to address these constraints. However, every new insect monitoring design needs to be evaluated with respect to reliability and bias based on comparisons with conventional methods. In this study, we evaluate the effectiveness of an automated moth trap (AMT), built from off‐the‐shelf‐hardware, in capturing declines in moth abundance, by comparing it to a conventional, lethal trap. Both trap types were operated five times on 16 plots from the beginning of July 2021 to the end of August 2021. On average AMTs recorded fewer individuals than conventional traps. However, both trap types depicted the same seasonal decline of approximately 3% per day, which corresponded to a total difference of ~85% over the sampling period. Given our sample size, both trap types had the same limitations in their reliability to detect smaller changes in abundance trends. This first proof of concept demonstrated that AMTs depict large magnitude events such as phenological patterns just as well as conventional, lethal traps. Therefore, AMTs are a promising tool for future autonomous and non‐lethal monitoring, which paves the way for high temporal coverage and resolution in insect monitoring. However, this initial quantitative field test revealed that its long‐term applicability must be preceded by several adjustments to the image quality, power supply and to data transfer.

Floral enhancement of arable field margins increases moth abundance and diversity

Moth populations have declined across large parts of north-western Europe since the mid-20th century due, in part, to agricultural intensification. Agri-environment schemes (AES) are widely implemented across Europe to protect biodiversity in agricultural landscapes. Grass field margins enriched with wildflowers typically out-perform grass-only margins in terms of increasing insect abundance and diversity. However, the effect of wildflower enrichment on moths remains largely unstudied. Here, the relative importance of larval hostplants and nectar resources for adult moths within AES field margins are investigated. Two treatments and a control were compared: (i) a plain grass mix, the control, (ii) a grass mix enriched with only moth-pollinated flowers, and (iii) a grass mix enriched with 13 wildflower species. Abundance, species richness and Shannon diversity were up to 1.4, 1.8 and 3.5 times higher, respectively, in the wildflower treatment compared to plain grass. The difference in diversity between treatments became greater in the second year. There was no difference in total abundance, richness or diversity between the plain grass treatment and grass enriched with moth-pollinated flowers. The increase in abundance and diversity in the wildflower treatment was due primarily to the provision of larval hostplants, with nectar provision playing a smaller role. The relative abundance of species whose larval hostplants included sown wildflowers increased in the second year, suggesting colonisation of the new habitat.Implications for insect conservation.We show that, at the farm scale, moth diversity can be greatly enhanced and abundance moderately enhanced by sowing diverse wildflower margins, providing these insects with both larval hostplants and floral resources, compared to grass-only margins.

Positive shifts in species richness and abundance of moths over five decades coincide with community-wide phenotypic trait homogenisation

While some species rapidly decline, compromising vital ecosystem services, others are stable or even increasing in abundance. We studied shifts in species richness and abundance of moths over five decades in Central Sweden and examined whether and how changes were associated with phenotypic traits. We combined information from captures in a light trap in historical time (the 1970s) and contemporarily (2019) with provincial colonisation records. Both community species richness and the abundance of moths increased between the time periods. A large fraction (38%) of the 410 species were not present in both periods, 101 species had colonised the area (an estimated influx of about 2.5 new species per year), and 51 species had disappeared (an estimated local extinction rate of about 1.16 species per year). Abundance increased with an increasing number of host plants and with increasing colour pattern variation. The composition of the community shifted towards species characterised by smaller wingspan and larger ranges. The functional trait variability of the moth community was homogenised from the historical to the contemporary period, in line with reports from other species communities in modern landscapes. However, our finding of a concomitant increase in species richness and total abundance differs from the results of many recent studies of insect communities in other geographic regions.Implication for insect conservationWe conclude that the entire boreal moth fauna is undergoing a substantial biogeographical shift, changing to the moth species historically occurring at more southern latitudes. The alterations in species composition, overall abundance, and community-wide trait distribution described here may cascade up and down in the ecosystem because moths are important pollinators, herbivores, and prey.

Diverse agricultural landscapes increase bat activity and diversity: Implications for biological pest control

Diverse landscapes consisting of mixed crops are expected to support higher biological control, while also contributing to maintain farmland biodiversity. Although bats are known as predators of many farming pests, few studies to date have investigated how their foraging activity may enhance natural pest control.Here, we tested the hypothesis that crop mosaics would provide a temporal continuity in prey availability for bats, ultimately resulting in higher biological control. We sampled bat activity and diversity, and the abundance and damage of three major pests of vineyards, maize, and pine plantations, in both simple and diverse landscapes mixing the three production types. Bat species richness and total activity were higher in vineyards and pine plantations located within diverse landscapes. Bat foraging activity also peaked within diverse landscapes. In vineyards, moth abundance decreased with bat species richness. In pine plantations, pest damage decreased with bat foraging activity. In maize fields, pest abundance and damage increased with bat richness and activity longer-term investigations would be necessary to assess their actual effectiveness. Our study advocates for promoting a diversity of coexisting crops within agricultural landscapes to enhance bat activity and diversity, which in turn would sustain higher biological control and bolster biodiversity conservation in farmland.

Diversity but Not Overall Abundance of Moths and Butterflies (Insecta: Lepidoptera) Decreases around Two Arctic Polluters.

Alarming reports on the rapid decline of insects during the past decades call for the exploration of potential drivers of this process. Here, we test the hypothesis that the overall abundance and diversity of moths and butterflies (Lepidoptera) decrease under the impact of industrial pollution in the fragile arctic environment. For this purpose, experienced collectors netted adult Lepidoptera at five tundra sites located 0.5 to 45.3 km from the ore-roasting plant in Zapolyarnyy and at five forest sites located 1.4 to 37.8 km from the copper-nickel smelter at Nikel, in the Murmansk region of Russia. The analysis of the 100 samples collected from 2003 to 2008 and containing 2312 individuals of 122 species revealed that the diversity of Lepidoptera declined significantly near both of these polluters due to both decreases in species richness and changes in the abundance of individual species, whereas the overall abundance of moths and butterflies was independent of the pollution load. These patterns did not differ between Nikel and Zapolyarnyy, and they were consistent with patterns previously found near the copper-nickel smelter at Monchegorsk. The abundances of Lepidoptera species showed variable changes along pollution gradients, from significantly negative to significantly positive, but individual species showed similar density changes around these three polluters. Disproportional increases in the abundance of a few pollution-tolerant species change the community structure and explain why the overall abundance of moths and butterflies does not decline even in localities experiencing extreme loads of sulphur dioxide and heavy metals.

The lunar nodal phase cycle and winter atmospheric pressure as possible determinants of moth abundance: Analyses of a30-year time series from South Norway.

According to the plant stress hypothesis, population peaks of herbivores such as moths are caused by plant stress factors that force plants to reallocate stored defensive proteins to transportable and easily digestive N‐compounds. A suggested plant stress factor is ionization caused by cosmic ray muons, which are modulated by the 9.3‐year lunar nodal phase cycle, solar activity, and atmospheric pressure. Vascular plants are more sensitive to ionization than are bryophytes, and woody plants are more sensitive than are herbaceous plants, but the difference may be less during dormancy in winter. We selected the 14 most common moth species from a 30‐year light‐trapping study in southern Norway to test whether the fluctuation patterns of species from three different feeding guilds were correlated with lunar/solar cycles, or with atmospheric pressure in winter, when muon fluxes are higher than in other seasons. The population indices of three species feeding on deciduous woody plants were positively correlated with the lunar nodal phase index, and there was a similar tendency for the remaining three species. No positive correlations with the lunar index were found for species feeding on herbs or mosses. For nine species, that is, from all three guilds, there was a significant negative correlation between the population index and winter atmospheric pressure in the previous year. The results are in accordance with predictions deduced from the cosmic ray hypothesis, but thorough investigations of the proposed physiological mechanisms are needed for the hypothesis to be widely accepted.

Eastern Whip-poor-will abundance declines with urban land cover and increases with moth abundance in the American Midwest

Abstract Populations of avian aerial insectivores have declined across North America. A leading factor hypothesized to be driving these trends is a decline in prey populations, although a loss of suitable habitat on the landscape or other factors may also play a role. The Eastern Whip-poor-will (Antrostomus vociferus; hereafter: whip-poor-will) is an aerial insectivorous nightjar that has disappeared from many of its historic breeding locations. We investigated the role that food availability and land cover at multiple scales play in whip-poor-will distribution by estimating their abundance at 23 sites across central Illinois. To do this, we conducted nocturnal point counts to estimate whip-poor-will abundance and collected nocturnal insects using UV-light traps at these sites to quantify potential food abundance. Additionally, we described whip-poor-will diet using DNA metabarcoding of fecal samples. We found that the number of large moths at a site had a positive effect on the abundance of whip-poor-wills, aligning with our diet analysis which identified moths as the primary prey item for this species (present in 92% of samples). Whip-poor-wills also showed an affinity for forest edges, but only when edges were associated with high moth abundances. Conversely, developed land-cover in landscapes surrounding sites led to decreased whip-poor-will abundance. Given the continued expansion of developed areas, coupled with concerning trends in moth populations, declines in the abundance of this species may continue. Efforts should be made to protect and sustain moth populations and the impacts of development should be scrutinized in the pursuit of conserving whip-poor-wills.