Insect Abundance Research Articles

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.

Aquatic insects (Ephemeroptera, Plecoptera, Trichoptera and Diptera: Tipuloidea) from the upper Neretva in Bosnia-Herzegovina

Within the upper Neretva catchment in Bosnia several hydropower plants are projected. Between 28.6. and 1.7.2022 a baseline survey was initiated to screen the area regarding the diversity of aquatic insects and its linked conservation value. In total, 59 Trichoptera species, ten Plecoptera species, 19 Ephemeroptera and 16 Diptera (Tipuloidea) species were collected, of which Baeoura sp. is new to science. 35 species are endemics of the Balkans, most species are rheobiontic and need high water current. The most abundant taxa are species of the trichopteran genus Agapetus (A. slavorum and A. ochripes) – surface grazers sensitive to water fluctuations and therefore vulnerable to hydropower-induced water level changes. With estimated 40,000 attracted specimens per night, light traps were extraordinarily successful. The extremely high diversity, as well as the enormous abundance of aquatic insects, underline the importance of the upper Neretva as an unimpacted riverine system embedded in dense natural and near-natural forest.

Photonic sensors reflect variation in insect abundance and diversity across habitats

To mitigate ongoing insect biodiversity declines, there is a need for efficient yet accurate monitoring methods. The use of traditional catch-based survey methods is constrained both by costs and need for expertise for manual taxonomic identification. Emerging methods, such as eDNA and robotic sorting, have the potential to reduce workload but still require resource-intensive sample collection in the field. Recently, remote sensing methods such as photonic sensors have shown promise for recording large numbers of insect observations. However, accurately determining species composition in collected data remains a challenge.In this study, we investigated the potential of photonic sensors for quantifying species richness of flying insects in the field and at five sites and compared the results with estimates based on conventional Malaise traps. Firstly, we evaluated two unsupervised clustering methods using a library of measured insect signals from 42 known species. Secondly, we correlated estimated number of clusters in data recorded at five sites with species richness assessment of catches from Malaise traps. This study is based on 84,770 library- and 238,584 field individual insect recordings. Our results demonstrate that both clustering methods perform well and reflect estimates obtained by Malaise traps, indicating the potential of automated insect biodiversity monitoring. This offers the possibility of more efficient but still accurate methods for studying insect biodiversity with broader temporal and spatial coverage.

Seasonal changes in community composition and abundance of aquatic insects and gastropods in rice fields

Seasonal changes in community composition and abundance of aquatic insects and gastropods in rice fields

The Diversity of Forensic Entomofauna Associated With Decaying Chicken Liver in the Tropical Region of Kerala, India.

Forensic entomology To elucidate the time of death based on insect evidence, there are several studies on forensic entomology on life cycles, environmental factors, and feeding habitats of insects. However, there have not been any comprehensive studies on forensic entomology and its usage in forensic inquiry specific to the region, especially Kerala, India. The insect succession on decomposed animal matter plays an important role in estimating minimum postmortem intervals (mPMI). Objective The purpose of the study was tounderstand forensically important insect groups and their role in the decomposition process of dead decayingmatter. The different decomposition stages of a corpse vary in attraction to necrophagous insects and the insect fauna depending on its prevailing conditions of decay. The decomposition is highly dependent on the exposition of animal matter and abiotic and biotic factors acting on it. The main objective of the present investigation was to identify the insect fauna associated with decaying chicken liver. The study also envisages comprising the diversity and abundance of insects between two different treatments of animal matter: in contact with soil and controlled conditions in a clean basin. Method The study was conducted for 45 days (until the total decomposition of the samples in both conditions) during the pre-monsoon months of April to May2022 at Chalikadavu, Muvattupuzha, in the Ernakulam district, Kerala, India. The samples were however kept away from direct sunlight and rain to avoid the direct impact on the orienting fauna. The entomofauna found to be associated with the decaying animal matter was carefully collected from the site and stored in 70% isopropyl alcohol for preservation. The total number of insects was recorded along with the hours of maximum incidence, and samples were stored in plastic vials for further identification. Result In this study, we analyzed the activities of ants, mites, wasps, cockroaches, moths, beetles, and flies during the decomposition of decaying chicken liver. Among these insects, flies and beetles are two important arthropod communities associated with animal matter decomposition. We collected these foraging organisms for morpho-taxonomic identification. The decomposition stages among the two treatments could help to understand the variable factors in the decomposition of decaying corpse with special reference to the insect fauna acting on it. Conclusion We got 100 specimens comprising 28 species in 17 families from Blattidae, Coleoptera, Diptera, Hymenoptera, and Lepidoptera. Besides this, we identified two parasitic wasps with their host (dipteran pupa), which is helpful in postmortem interval (PMI) estimation. Our analysis showed an association between decay and the activity of carrion insects. The decomposition stages among the two treatments could help to understand the variable factors in the decomposition of a decaying corpse with special reference to the insect fauna acting upon it.

Facilitating the recovery of insect communities in restored streams by increasing oviposition habitat.

Recruitment limitation is known to influence species abundances and distributions. Recognition of how and why it occurs both in natural and in designed environments could improve restoration. Aquatic insects, for instance, rarely reestablish in restored streams to levels comparable to reference streams even years after restoration. We experimentally increased oviposition habitat in five out of 10 restored streams in western North Carolina to test whether insect egg-laying habitat was limiting insect populations in restored streams. A main goal was to test whether adding oviposition habitat in the form of rocks that partially protrude above the water surface could be used to increase the abundance and richness of stream insect eggs and larval insects in restored streams. Adding egg-laying habitat enhanced several response variables (e.g., protruding rocks, number of eggs, egg masses, egg morphotype richness, and oviposition habitat stability) to levels similar to those found in reference streams. Following the addition of protruding rocks, egg mass abundance increased by 186% and richness by 77% in restored-treated streams. Densities of larval insects that attached their eggs to protruding rocks showed an overall pattern consistent with treatment effects due to the combination of nonsignificant and significant increases of several taxa and not just one taxon. Our results indicate that these stream insect populations are limited by oviposition habitat and that adding egg-laying habitat alleviated this component of recruitment limitation. However, the weaker larval response indicates that additional post-recruitment factors, such as egg or larval mortality, may still be limiting a full recovery of larval insect abundances in these restored streams. This study shows the importance of integrating information from animal life histories, ecology, and geomorphology into restoration practices to improve the recovery of aquatic insects, which are commonly used to assess water quality and the biological efficacy of stream restoration.

Disproportionate declines of formerly abundant species underlie insect loss

Studies have reported widespread declines in terrestrial insect abundances in recent years1–4, but trends in other biodiversity metrics are less clear-cut5–7. Here we examined long-term trends in 923 terrestrial insect assemblages monitored in 106 studies, and found concomitant declines in abundance and species richness. For studies that were resolved to species level (551 sites in 57 studies), we observed a decline in the number of initially abundant species through time, but not in the number of very rare species. At the population level, we found that species that were most abundant at the start of the time series showed the strongest average declines (corrected for regression-to-the-mean effects). Rarer species were, on average, also declining, but these were offset by increases of other species. Our results suggest that the observed decreases in total insect abundance2 can mostly be explained by widespread declines of formerly abundant species. This counters the common narrative that biodiversity loss is mostly characterized by declines of rare species8,9. Although our results suggest that fundamental changes are occurring in insect assemblages, it is important to recognize that they represent only trends from those locations for which sufficient long-term data are available. Nevertheless, given the importance of abundant species in ecosystems10, their general declines are likely to have broad repercussions for food webs and ecosystem functioning.

If you build it, will they come? Insect community responses to habitat establishment at solar energy facilities in Minnesota, USA

Global declines in insect populations have important implications for biodiversity and food security. To offset these declines, habitat restoration and enhancement in agricultural landscapes could mutually safeguard insect populations and their pollination services for crop production. The expansion of utility-scale solar energy development in agricultural landscapes presents an opportunity for the dual use of the land for energy production and biodiversity conservation through the establishment of grasses and forbs planted among and between the photovoltaic solar arrays (‘solar-pollinator habitat’). We conducted a longitudinal field study across 5 years (2018–2022) to understand how insect communities responded to newly established habitat on solar energy facilities in agricultural landscapes by evaluating (1) temporal changes in flowering plant abundance and diversity; (2) temporal changes in insect abundance and diversity; and (3) the pollination services of solar-pollinator habitat by comparing pollinator visitation to agricultural fields near solar-pollinator habitat with other agricultural field locations. We found increases over time for all habitat and biodiversity metrics: floral rank, flowering plant species richness, insect group diversity, native bee abundance, and total insect abundance, with the most noticeable temporal increases in native bee abundance. We also found positive effects of proximity to solar-pollinator habitat on bee visitation to nearby soybean (Glycine max) fields. Bee visitation to soybean flowers adjacent to solar-pollinator habitat were comparable to bee visitation to soybeans adjacent to grassland areas enrolled in the Conservation Reserve Program, and greater than bee visitation to soybean field interior and roadside soybean flowers. Our observations highlight the relatively rapid (<4 year) insect community responses to grassland restoration activities and provide support for solar-pollinator habitat as a feasible conservation practice to safeguard biodiversity and increase food security in agricultural landscapes.

Bioacoustic IoT Sensors as Next-Generation Tools for Monitoring: Counting Flying Insects through Buzz.

The global loss of biodiversity is an urgent concern requiring the implementation of effective monitoring. Flying insects, such as pollinators, are vital for ecosystems, and establishing their population dynamics has become essential in conservation biology. Traditional monitoring methods are labour-intensive and show time constraints. In this work, we explore the use of bioacoustic sensors for monitoring flying insects. Data collected at four Italian farms using traditional monitoring methods, such as hand netting and pan traps, and bioacoustic sensors were compared. The results showed a positive correlation between the average number of buzzes per hour and insect abundance measured by traditional methods, primarily by pan traps. Intraday and long-term analysis performed on buzzes revealed temperature-related patterns of insect activity. Passive acoustic monitoring proved to be effective in estimating flying insect abundance, while further development of the algorithm is required to correctly identify insect taxa. Overall, innovative technologies, such as bioacoustic sensors, do not replace the expertise and data quality provided by professionals, but they offer unprecedented opportunities to ease insect monitoring to support conservation biodiversity efforts.

Low foraging rates drive large insectivorous bats away from urban areas

AbstractUrbanization has significant impacts on wildlife and ecosystems and acts as an environmental filter excluding certain species from local ecological communities. Specifically, it may be challenging for some animals to find enough food in urban environments to achieve a positive energy balance. Because urban environments favor small‐sized bats with low energy requirements, we hypothesized that common noctules (Nyctalus noctula) acquire food at a slower rate and rely less on conspecifics to find prey in urban than in rural environments due to a low food abundance and predictable distribution of insects in urban environments. To address this, we estimated prey sizes and measured prey capture rates, foraging efforts, and the presence of conspecifics during hunting of 22 common noctule bats equipped with sensor loggers in an urban and rural environment. Even though common noctule bats hunted similar‐sized prey in both environments, urban bats captured prey at a lower rate (mean: 2.4 vs. 6.3 prey attacks/min), and a lower total amount of prey (mean: 179 vs. 377 prey attacks/foraging bout) than conspecifics from rural environments. Consequently, the energy expended to capture prey was higher for common noctules in urban than in rural environments. In line with our prediction, urban bats relied less on group hunting, likely because group hunting was unnecessary in an environment where the spatial distribution of prey insects is predictable, for example, in parks or around floodlights. While acknowledging the limitations of a small sample size and low number of spatial replicates, our study suggests that scarce food resources may make urban habitats unfavorable for large bat species with higher energy requirements compared to smaller bat species. In conclusion, a lower food intake may displace larger species from urban areas making habitats with high insect biomass production key for protecting large bat species in urban environments.

Biodiversity and Succession of Insects of Blackgram (Vigna mungo (L.) Hepper) During rabi in the Western Undulating Zone of Odisha

The field experiment was conducted to study about insect biodiversity and their succession in blackgram crop at the crop research farm, College of Agriculture, OUAT, Bhawanipatna during rabi 21. Twenty seven insects belong to seven orders and twenty two families were recorded during different growth stages of crop in an overlapping manner. Beside the insects twelve numbers of predators, three numbers of parasitoids and two pollinators were also noticed. The highest diversity index and evenness of insects were recorded at 42 SMW (0.902 and 1.000) followed by 50 SMW (0.833 and 0.710) respectively. The diversity of insects was almost uniform because of the evenness of the species. The insect order homoptera and the insect white fly came under superdominant class of dominance during all the growth stages of crop, whereas coleoptera and hemiptera were categorized under sub-dominant class at vegetative stage and flowering to podding stage of crop growth respectively. The insect orders hemiptera, coleoptera, diptera and hymenoptera and the insects i.e., galerucid beetle, jassid, stem fly, aphids and thrips came under recedent class of dominance. The relative abundance and dominant status of insect’s revealed that the maximum numbers of insects were belongs to orders homoptera (75.22%) followed by hemiptera (7.92%), coleoptera (6.30%), diptera (4.62%), hymenoptera (4.05%), orthoptera (0.89%), lepidoptera (0.86%) and odonata (0.09%).Chrysomelid beetles were noticed first during the early vegetative stage of crop followed by stem fly, white fly, leaf webber and semiloopers at the vegetative stage, tobacco caterpillar from late vegetative to pod filling stage, thrips in flowering stage, pod borers, pod bugs, aphids, pentatomid bugs and bihar hairy caterpillar from flowering to crop maturity stage and the pod fly and pod wasp from pod filling to pod maturity stage of the crop. Jassids, grasshoppers and predators like spiders, coccinellids beetles and parasitoids were appeared from mid vegetative stage and continued till fag end of the crop. The peak activities of insects were recorded from flowering to pod maturity stage of the crop.

Impacts of livestock grazing on blue‐eared pheasants (Crossoptilon auritum) survival in subalpine forests of Southwest China

AbstractThe degradation and fragmentation of natural habitats, driven largely by anthropogenic activities such as grazing, represent growing concerns in environmental conservation. We examined the impact of grazing activities on the survival of the blue‐eared pheasant Crossoptilon auritum, a ground‐nesting bird endemic to subalpine forests. Using camera‐trapping and artificial nest experiments, we compared two sites in Sichuan, China: Wanglang (high grazing intensity) and Jiuzhaigou (no grazing) national nature reserves. The study, conducted from 2017 to 2021, evaluated habitat suitability changes for these pheasants and examined the impact of grazing on nesting success by conducting a nest predation experiment. The results of our study showed that (1) since the significant increase of free‐ranging livestock post‐2014, the area of most suitable and moderately suitable habitats for blue‐eared pheasants in Wanglang decreased by 14.28% (net loss 15.12 km2); (2) predominant natural predators of the pheasant, such as yellow‐throated martens (Martes flavigula) and leopard cats (Prionailurus bengalensis), were mostly observed to be spatially distant from livestock; (3) the pheasant's nesting failure rate was 2.18 times higher in Wanglang than in Jiuzhaigou; (4) high‐intensity livestock disturbance correlated with decreased food resources for pheasants, yet resulted in an increased abundance of Coleopteran insects. These results illustrate a complex dynamic: Although forest pheasants, such as the blue‐eared pheasant, may initially benefit from the presence of livestock through increased predator refuge and access to specific food resources, they ultimately face greater risks. These include a significant increase in nest failure rates and remarkable habitat loss and degradation. In light of these results, we advocate for strict control and management of grazing activities inside reserves. Additionally, we recommend the implementation of a systematic monitoring program that focuses on the population dynamics and habitat use of endangered pheasants in Southwest China.

PENGARUH PUPUK LIMBAH CINCAU TERHADAP PENYAKIT DAN KEANEKARAGAMAN SERANGGA TANAMAN JAGUNG

Utilization of organic fertilizer aims to increase soil fertility and efforts to improve the balance of the corn plant ecosystem. One source of organic fertilizer is black grass jelly waste, both solid and liquid. Black grasss jelly waste is available in excess because factories that produce black grass jelly have not utilized the waste as an alternative to organic fertilizer. The purpose of this study was to determine the effect of organic fertilizer from black grass jelly waste both solid and liquid on the abundance of insects and their natural enemies. This research started from September to December 2021. It took place at the Integrated Field Laboratory, Kadiri Islamic University, in Rejomulyo Village, Kediri City, with a pH of 7, daily temperature and humidity (±28.3°C and 72.2%) with rainfall 45 mm/month. Variable observations of downy mildew disease sentitivity index and insect diversity. The results showed that the effect of grass jelly fertilizer had an effect on the level of resistance to downy mildew attacks. In all the insects found were 47 families consisting of 6 orders. On diversity has a moderate value. In terms of evenness and species richness, it was found that all the results had high scores. So that the treatment of solid and liquid fertilizers against insect diversity is very good.

Utilizing net traps to manage pyralid insect population in pond ecosystems: investigating seasonal abundance and their association with duckweeds

A one-year (May to April) study was done about the seasonal abundance of pyralid insect (Synclita occidentalis: Pyralidae), its association with the duckweed (Spirodela sp.), and the effectiveness of emergent trap as a control measure of pyralid insect in mini ponds ecosystem. The adult insects were non-feeding and selected duckweeds for oviposition and larval development. The larvae of different instars were used duckweed fronds as a trophic source (food). For this, the insect attains pest status in its larval stage. The duckweed production is highly hampered due to the attack of this pyralid insect in pond ecosystem. During experiment, two seasonal peaks were noted, one in summer and another in autumn (larvae and adults). The highest relative seasonal abundance of the adults was recorded in June (0.2) and larvae was in August (0.23). The lowest abundance of the adults and larvae was found 0.001 and 0.01, respectively during winter season. In this experiment, it was found that larvae used duckweed fronds as food in maximum 18.86 ± 0.86 and minimum 13.33 ± 0.70. The larva also built protective cases in duckweed fronds. The highest length of the larval cases was 27.07 ± 1.7 mm and width was 14.8 ± 1.75 mm. The larval feeding habit and case-making adaptability give this insect pest status. From the experiment, it was also found that the length and width of the larval cases greatly varied in different seasons and not positively correlated (P &gt; 0.005). The total seasonal abundance of larval cases was lower in treatment ponds (54) than control (103); and not varied significantly (P &gt; 0.005) between the experimental ponds. In addition, the net trap of adult’s emergent had an important role in suppressing pyralid pest population especially in summer. This situation indicated that it might be a key contribution as a control planning during the peak season of pyralid pest outbreak for the management of duckweed in aquatic ecosystems. Biodivers. Conserv. Bioresour. Manag. 2023, 9(2): 99-108

Mammal communities of primeval forests as sentinels of global change.

Understanding the drivers and consequences of global environmental change is crucial to inform predictions of effects on ecosystems. We used the mammal community of Białowieża Forest, the last lowland near-primeval forest in temperate Europe, as a sentinel of global change. We analyzed changes in stable carbon (δ13 C) and nitrogen (δ15 N) isotope values of hair in 687 specimens from 50 mammal species across seven decades (1946-2011). We classified mammals into four taxonomic-dietary groups (herbivores, carnivores, insectivores, and bats). We found a significant negative trend in hair δ15 N for the mammal community, particularly strong for herbivores. This trend is consistent with temporal patterns in nitrogen deposition from (15 N depleted) industrial fertilizers and fossil fuel emissions. It is also in line with global-scale declines in δ15 N reported in forests and other unfertilized, non-urban terrestrial ecosystems and with local decreases in N foliar concentrations. The global depletion of 13 C content in atmospheric CO2 due to fossil fuel burning (Suess effect) was detected in all groups. After correcting for this effect, the hair δ13 C trend became non-significant for both community and groups, except for bats, which showed a strong decline in δ13 C. This could be related to an increase in the relative abundance of freshwater insects taken by bats or increased use of methane-derived carbon in food webs used by bats. This work is the first broad-scale and long-term mammal isotope ecology study in a near-primeval forest in temperate Europe. Mammal communities from natural forests represent a unique benchmark in global change research; investigating their isotopic temporal variation can help identify patterns and early detections of ecosystem changes and provide more comprehensive and integrative assessments than single species approaches.

Similar temporal patterns in insect richness, abundance and biomass across major habitat types

Abstract While many studies on insect diversity report declines, others show stable, fluctuating or increasing trends. For a thorough understanding of insect trends and their effects on ecosystem functioning, it is important to simultaneously assess insect richness, abundance and biomass, and to report trends for multiple taxa. We analysed insect richness, abundance and biomass data for all insects and for eight insect taxa (Buprestidae, Cerambycidae, Carabidae, other Coleoptera, Aculeata, other Hymenoptera, Heteroptera and Lepidoptera) from 42 sites across Switzerland from 2000 to 2007, representing three major habitat types in Switzerland (agricultural, unmanaged [open and forested] and managed forest habitats). As potential drivers of temporal patterns, we evaluated weather‐ and land‐use‐related factors. As predictors, we included temperature and precipitation as well as the vegetation index and the habitat type, respectively. We found a consistent pattern of stable or increasing trends for richness, abundance and biomass of insects in total and the eight taxa over 8 years. Both overall patterns and six out of eight taxa (except for Cerambycidae and Lepidotpera) showed the highest values in agricultural habitats. However, when accounting for elevation, there was no difference in open habitats regardless of whether they were used agriculturally. Habitat types were the most important predictors, followed by weather‐ and vegetation‐related factors. Modelled responses to mean temperature were unimodal, whereas the standard deviation of temperature showed positive and precipitation negative effects. Longer time series are needed to draw robust inferences and to investigate potential negative effects of future warming.

Diversity of Insects of Two Rice (Oryza sativa L. 1787) Farms in Nnamdi Azikiwe University, Awka, Nigeria

The recognition of insect-related damages to rice plants and the subsequent consequences for biodiversity have shown the relevance of insect communities in rice farms. This study documented the insect fauna of rice (Oryza sativa L. 1787) in two rice farms in Nnamdi Azikiwe University, Awka, Nigeria from September to November, 2022. The insects associated with the two sites were collected using handpicking, sweep net, water trap and pitfall trap methods. Data collected from the study were subjected to non-parametric t- test at 5% significant level. A total of 51,021 insects belonging to twelve insect orders were found associated with the two sites. Out of the aforementioned number, 15,120 (29.63%) were collected from site 1 while 35,901 (70.37%) were collected in site 2. There was significant difference (P &lt;0.05) on insect abundance between site 1 and 2. Crematogaster peringueyi was found to be the most abundant (82.67%) insect in site 1, whereas Camponotus perrisi was found to be the most abundant (27.85%) in site 2. The result further showed that only Hobomok skipper had the least relative abundance (0.01%) in site 1, while Catantops quadratu, Anacatantops notatus, Dysdercus cingulatus, Crematogaster peringueyi, Dasyleurotettix infaustus and Apis mellifera had the least relative abundance (0.01%) in site 2. The diversity indices computed showed that Site 1 had a higher Simpson dominance index (0.6845), Shannon Weiner diversity index (1.07597) and Shannon Weiner evenness than site 2 (0.0019, 0.41248and 0.0393 respectively). The Margalef richness index (6.3879) of site 2 was greater than site 1 (4.9876).There is need for regular monitoring of insects in rice farms for sustainable management of the crop.

Time-Series Characterization of Grassland Biomass Intensity to Examine Management Change at Two Sites in Germany Using 25 Years of Remote Sensing Imagery

In cultivated landscapes, grasslands are an important land use type for insect life. Grassland management practices can have a significant impact on insect ecology. For example, intense fertilization and frequent cutting can reduce the diversity and abundance of insects by destroying their habitat and food sources. Thus, the quality of grassland habitat for insect development depends on its management intensity. The intensification of grassland production is discussed as one factor contributing to the decline in insect biomass over recent decades. Characterizing grassland changes over time provides one piece to the larger puzzle of insect decline. We analyzed landscape-level trends in grassland biomass near Orbroich and Wahnbachtal in North Rhine-Westphalia, Germany, over a 25-year period. In both areas, pronounced insect biomass decline had been observed. More than 430 Landsat images were used. An image normalization process was developed and employed to ensure that observed changes over time were attributed to grassland changes and not systemic changes inherent within image time series. Distinct clusters of grassland parcels were identified based on intensity and temporal changes in biomass using Normalized Difference Vegetation Index (NDVI) as an indicator. Cluster separability was confirmed using the Transform Divergence method. The results showed clusters having periods of distinct trends in vegetation biomass, indicating changes in grassland agronomic and/or management practices over time (e.g., fertilization, increased silage production). Changes in management practices coincided with regional trends in cultivation as documented by official statistics. We demonstrated the feasibility of using 100+ images over multiple decades to perform a long-term remote sensing analysis examining grassland change. These temporally expansive and spatially detailed trends of grassland change can be included as factors in the multi-variate analysis of insect decline. The methodology can be applied to other geographic areas. Such improved insights can support informed landscape design and cultivation patterns in relation to insect ecology and the broader context of biodiversity enhancement.

Effects of Temperature and Rainfall Pattern on The Abundance of Orthopteran Insects in Coal Mines Ecological Restoration Areas of Jharia Coal Fields, Jharkhand, India

Ecological restoration on coal mines' overburden dumps provides a suitable environment for the study of primary succession. The Abundance and diversity study of orthopteran insects and their diversity pattern with temperature and rainfall provides a lot about the stage of succession and ecosystem complexity in the area. Orthopteran diversity of two sites covering ten years of plantation having different types of vegetation were monitored. Tropical conditions like changes in rainfall and temperature influence the abundance of insects. An increase in monsoon increases the abundance whereas as the temperature increases the abundance decreases. In herbaceous habitats, insects’ diversity increases which gives a recolonization pattern for the ecosystem. This helps to increase the livelihood and conservation of the ecosystem and directs to sustain the SDG 15 goal.

Anthropogenic disturbance affects specialist, but not generalist, endophagous insects associated with two African grasses: implications for biological control

ABSTRACT The specialisation-disturbance hypothesis (SDH) predicts that specialist and generalist taxa respond differently to disturbance, with generalists more tolerant of disturbance, while habitat stability (i.e. no/limited disturbance) should favour specialist species. If the SDH holds true, this would have implications for the design and implementation of biological control programmes, in terms of performing native-range surveys in search of candidate agents and subsequent development of management programmes for their release in the weeds invaded range. We assessed the effect of anthropogenic disturbance (mowing/slashing and fire) on the endophagous insect communities associated with two African grasses, Sporobolus pyramidalis and Sporobolus natalensis (Poaceae), that are targets for biological control in Australia. Comparisons, of insect community structure and presence/abundance of each species between disturbed and undisturbed sites, were made at 19 sites in South Africa. Disturbance caused a shift in insect species composition and abundance, whereby specialist insects were less frequently encountered and less abundant at disturbed versus undisturbed sites. If the potential agents for Sporobolus spp. are released in Australia they may be negatively affected by disturbance and may therefore be incompatible with certain integrated management strategies, such as mowing and prescribed burning. Moreover, our results suggest that field sites with limited disturbance should be prioritised during native-range surveys to maximise the chances of locating specialist natural enemies. The effect disturbance has on insect community composition may be particularly relevant for the biological control of invasive grasses, due to the intensity of disturbance of grasslands worldwide.