Pollination is an important ecosystem service for both crop and wild plants. In recent decades, many pollinators have been experiencing population declines due to land-use changes and intensi ed agriculture. However, effects of anthropogenic landscapes on bee pollinators in the tropics are still little investigated. We analyzed the effects of landscape composition on the colony weight as well as foraging activity and patterns of the tropical Asian stingless bee species Tetragonala fuscobalteata which is a vital generalist pollinator in Southeast Asia. Twenty-eight colonies were established and monitored over a year in 19 mixed fruit orchards located along a gradient of human land-use intensity. Our results revealed that the colonies gained weight and increased their foraging activity over time across diverse landscapes including forest, agricultural, and urbanized areas, indicating that this bee species can well adapt to anthropogenic landscapes. Interestingly, T. fuscobalteata colonies also gained weight rapidly in orchards located in predominately agricultural landscapes with e.g. high proportions of rubber and oil palm plantations as well as in fruit orchards (such as rambutan, durian, coconut, banana). This positive effect was possibly due to mass owering crops providing abundant resources, i.e., pollen and nectar, for a limited time. We also show that T. fuscobalteata foragers could rely on urbanized land (probably ornamental plants and some crops in home gardens and backyards) and wild plants in surrounding forest patches during non-owering periods of crops. Our ndings thus indicate that the combined oral resource availability provided by heterogeneous anthropogenic landscapes, including agricultural elds, urbanized areas and forests, can sustain generalist pollinators.

Megachile (Chalicodoma) parietina (Geoffroy, 1785) is a Palearctic solitary bee included in the Red List of some central European Countries. Females build durable nests, reused year after year, by mixing soil with a salivary secretion. Like for most solitary bees, the resources contained within M. parietina nests attract several other insects which exploit pollen supplies or feed on the immature brood. These associated insects have mainly been studied for mantained bees and considered for their effect on the host reproductive success.A very large nesting aggregation of M. parietina in Central Tuscany has been studied for three consecutive years. We have identified 32 associated insect species, which certainly are an underestimate of the species present. Among the identified species, only eight had been previously reported for M. parietina. All the species were classified both according to the specificity for the host taxon (Chalicodoma, Megachilidae, Anthophila, Hymenoptera, Others) and to the ecological relationship (cleptoparasites, parasitoids, predators of larvae, food commensal, scavengers, and occasional nest users).This highlighted both the richness of the ecological network within the nesting aggregation and the value of studying these nesting sites to fill Eltonian shortfalls, i.e. the deficiency in ecology knowledge, of bees and their associated fauna.Implications for insect conservation.We suggest that, besides their role in pollination, large and stable bee nesting sites increase the local insect biodiversity, and that attention should be paid to their conservation within actions aimed to support populations of wild pollinators.

Heterogeneity at local and landscape scales can promote insect diversity and moderate insect declines that stem from global change. Determining how species respond to different landscape components provides insight into the role of heterogeneity in landscapes undergoing change. We examine how indigenous forest-grassland edges are used by butterflies. We assessed butterfly diversity and behaviour at forest edges and adjoining grassland, and tested whether these patterns are influenced by differing weather conditions between seasons. Forest edges supported a species rich butterfly assemblage. Forest specialists were more diverse at forest edges than in grassland, whereas grassland specialists and habitat generalists were as diverse at forest edges as in grassland. All butterfly groups showed more inter- and intra-specific interactions and more patrolling behaviour at forest edges, but more feeding and transient behaviour in grassland. Occurrence and behavioural patterns were not mediated by season, suggesting that the influence of forests does not change with varying environmental conditions. Nonetheless, certain species preferentially utilized forest edges in the hot and windy season, indicating that shelter provided by forest edges influences butterfly habitat use. We found no evidence that complementary nectar sources influence butterfly distribution patterns.Implications for insect conservation: The diverse butterfly assemblages and range of behaviours supported by indigenous forest edges indicate that forest patches are an important habitat component for butterflies. Conserving forest patches in these coastal grasslands may help buffer butterfly populations against global change.

Clearing of woodlands is used by graziers to promote pasture production, even though understanding of impacts of clearing on native fauna is lacking. We evaluate impacts of clearing on biodiversity by comparing invertebrates associated with ground-layer vegetation of cleared woodlands (grasslands) to that of nearby uncleared woodlands. Two replicates of grasslands consisting of pastures dominated by introduced grasses were compared with two woodlands at each of four locations. The adjacent riparian forest to each grassland and woodland site allowed evaluation of the effect of woodland clearing on the adjacent riparian zone. All habitats were grazed. Invertebrates of ground-layer vegetation were sampled using three suction subsamples of 1m2 at each site. Grasslands had significantly lower order richness and abundance of herbivores, pollinators and macroinvertebrates (food for birds) than the woodlands, whereas the riparian forests closely resembled each other in all metrics. Invertebrate assemblages of grasslands also differed significantly from those of the woodlands. BEST analysis showed that groundcover and leaf-litter percentage cover correlated strongest with invertebrate composition. This study has demonstrated that grazing management relying on clearing of fertile grassy woodlands of the rangelands of Central Queensland alters invertebrate diversity and assemblage. Thus, tree clearing not only leads to biodiversity losses in the canopy layer, but also in the ground-layer vegetation.Implications for insect conservationPastoralists have the capacity to improve outcomes for invertebrate biodiversity by maintaining groundcover (ground-layer vegetation and litter cover) above 80%, by encouraging native pastures over introduced species such as Buffel Grass and by retaining native woodlands.

Urbanized areas can impose selective pressures on insects which can be identified at the individual level based on animal physiological condition. Physiological condition can be measured from variables such as body size, body mass or energetic budget of individuals. We examined whether body mass, wing spot size and energy reserves (proteins, lipids and carbohydrates) were reduced as urbanization increases, using adults of two damselflies, Hetaerina americana and H. vulnerata, in Central Mexico. We used a Habitat Integrity Index to assess the degree of urbanization in our sampled sites, considering biophysical attributes and the impact of anthropogenic activities. We did not find relation of above individual variables with urbanization degree. These results support possible resilience of rubyspot damselflies in the face of radical changes such as urbanization. Our finding echoes other results in damselflies research.Implications for insect conservationOur results highlight the resilience of these damselflies species in the face of urban disturbances. Thus design cities considering not only requirements of humans is essential to promote the presence and conservation of these and other species of insects in cities.Graphical abstract

The frosted el n Callophrys irus (Godart) (Lepidoptera: Lycaenidae), is an imperiled species endemic to re-maintained habitats in eastern North America. C. irus spends the majority of the year as pupae that may be vulnerable to res that occur during this life stage. One way C. irus survives re is to burrow and pupate under the soil, but this behavior is variable between individuals. We ran an ex-situ test on the impact of two abiotic factors on the pupation depth of C.irus (n = 60): ambient temperature and soil moisture. We used two incubators at 18 ºC and 30 ºC in addition to two moisture conditions of 5 and 15%. The null model outperformed other models, suggesting the effects of soil moisture and temperature on depth were negligible. The number of caterpillars that burrowed was similar to previous work with nine caterpillars that burrowed fully beneath the soil surface. If in-situ burrowing rates re ect our ndings high mortality rates can be expected from re. Thus, small, isolated populations may require arti cial interventions. Our results support previous recommendations on the importance of refugia and population/habitat-speci c rotational burn schedules to ensure the long-term persistence of the species.

The wild bee community of a sand steppe habitat in Eastern Austria was surveyed in the years 2018 and 2019, complemented with historical data from over 100 years, and analyzed in relation to land use change. The mapping of land use categories was based on historical aerial photographs and orthophotos. Changes in bee community composition were analyzed by a multivariate statistical approach and took ecological traits into account (lecty, nesting type, habitat requirements, flight period, parasitism). In total, 310 bee species were recorded in the area, with the oldest records dating back to 1882. The bee species composition differed significantly among four defined time periods. Across the two most intensively sampled time periods (1931–1966 vs 2001–2021), a decline in species richness of over 50% was observed. We observed a disproportionally high decline of steppe- and sand-associated species, and a distinct shift from ground nesting species to above-ground nesting species. The area covered with woods increased from 1966 to 2018, while the total area covered with grassland and fallows decreased slightly between 1966 and 1994. The oligolectic species assemblage was specialized on Dipsacaceae, Brassicaceae and Fabaceae in the two earlier periods, and on Asteraceae and specifically on Carduoideae during the two later ones.Implications for insect conservationstronger reference to historic land management practices as short time periods of intensive grazing and small-scaled, staggered mowing would be desirable to improve the habitat quality. More drastic measures, such as removal of the topsoil in some parts and changes in the landscape re-establishing exposure to wind erosion, might be necessary, if the area is to be fully restored to the condition it was in a century ago.

Conservation measures such as those under the European Green Deal aim to counteract the biodiversity loss by increasing the share of organic farming and reducing pesticide use, as well as increasing the proportion of semi-natural habitats (SNH) in agricultural landscapes. Given the large environmental impacts of agriculture, it is important to thoroughly understand effects of such measures on organisms to provide evidence-based and effective implications for conservation. In this study, we analysed how vineyard management, pesticide reduction, and landscape composition affect Orthoptera densities and species composition. Therefore, we sampled herb- and vine-dwelling orthopterans in a paired design of classic and fungus-resistant grape (FRG) varieties in conventionally and organically managed vineyards along a landscape heterogeneity gradient. Here, FRG varieties allowed us to study the effect of 44% reduced pesticide applications under real-world conditions. Total densities of herb-dwelling Orthoptera did not differ between grape varieties in conventional vineyards, but were 2.9 times higher in FRG varieties under organic management. In contrast, total densities of vine-dwelling Orthoptera, mainly driven by the dominant species Phaneroptera falcata, were similar between grape varieties in organic vineyards, but tended to be 1.4 times higher in classic grapes under conventional management. Furthermore, the management system and SNH in a radius of 500 m in the surrounding landscape influenced species composition.