Radar as a Key to Global Aeroecology

Open, systematic, and global approaches are needed to address the challenges of aeroconservation and pest management. Recent technical progress enables deeper investigation and understanding of aeroecology. Radar plays a central role in flying species monitoring in the global scope. The technology provides various ways of target detection and tracking, working for multiple ranges and different visibility. The existing technology allows deploying global monitoring of avian and insect species. This work discusses the essentials of the technology and the history of its application for bird and insect detection. The author describes the development of the topic according to the main groups of radar approaches: pulsed sets, vertical-looking solutions, harmonic systems, and efficient frequency modulated continuous wave radar. Advances in big data processing, robotics, computation, and communications enable practitioners to combine the discussed radar solutions aiming at global avian and insect biodiversity monitoring and negative human impact systematic estimation.

Experimental calibration of trapping methods for addressing bias in arthropod biodiversity monitoring

1.SummaryAll approaches to biodiversity monitoring have inherent biases in the taxa captured, yet, as environments, sampling goals, and conventions vary, it is not uncommon for sampling approaches to be customized to reflect the study objectives, optimizing findings to be locally relevant but at the cost of transferability. Here, we developed a calibration study to directly examine how researcher trap choice affects observations made in insect biodiversity sampling. Sampling efficiency of four types of traps: pitfalls, yellow ramp traps, a novel jar ramp trap, and yellow sticky cards, were compared with respect to an array of biodiversity metrics associated with the arthropods they captured. We found that trapping efficiency and functional groups of arthropods (flying versus ground-crawling) varied by trap type. Pitfalls and jar ramp traps performed similarly for all biodiversity metrics measured, suggesting that jar ramp traps provide a more comparable measurement of ground-crawling arthropod communities to pitfall sampling than the yellow ramp traps and should be considered when pitfall sampling cannot be used. This study illustrates the implications for biodiversity sampling of arthropods in environments with physical constraints on trapping, and the importance of directly comparing adapted methods to established sampling protocol. Future biodiversity monitoring schemes should conduct calibration experiments to provide important information on performance and potential limitations of sampling methodology.

Faunistic analysis of insects of Deva Vatala National Park and agroecosystem of Gujrat Pakistan

Insect biodiversity drives ecological functioning and provides ecosystem services in different landscapes. Protected areas with the least anthropogenic disturbances provide resources with the least disturbance in habitat favouring insect species belonging to different guilds to coexist and contribute to the ecosystem processes. Studies have highlighted the significance of anthropogenic landscapes including agricultural ecosystems for harboring rich native biodiversity. To understand the species composition and abundance agricultural landscape, we explored insect fauna in Deva Vatala National Park (DVNP), Bhimber (Azad Kashmir), and associated croplands of Gujrat, Punjab, Pakistan. We aimed to assess the abundance, richness and diversity of the insect orders, families and species found in the two habitats i.e. national park and croplands. Fortnightly surveys were conducted during 2017-2019. Sampling methodology consisted of handpicking, using sweep nets, light traps, pitfall traps and insect collection was identified by using taxonomic keys. A total of 239 insect species representing 10 orders and 69 families were collected and identified from both habitat types. For both diversity and abundance, we detected a significant difference in community composition at species, family and order levels. Several insect orders and families demonstrated significant differences (p< 0.05) in either abundance or richness or both between the two types of habitats. Several families of Coleoptera, which contains dung beetles, ground beetles, ladybird beetles showed greater richness in DVNP. However, we also detected that several insect orders showed greater richness in the croplands of Gujrat. But we observed the pattern of the greater abundance of insect orders in DVNP. Both types of habitat can have important consequences on insect fauna having great importance in the ecosystem services and functions. Protected areas nearby associated croplands have the potential to contribute immensely to biodiversity conservation and ecosystem service provision both at the local scale and the landscape scale.

Effectiveness of Multifunctional Margins in Insect Biodiversity Enhancement and RTE Species Conservation in Intensive Agricultural Landscapes

Starting in the 1950s, agricultural production has been remarkably intensified, resulting in modern management systems where a severe increase in field size led to an elimination of edges and other ecologically valuable structural elements. The resulting habitat loss caused dramatic changes in natural communities. The aim of this work is to test whether there are statistically significant differences in insect abundance over time by using multifunctional margins that are seed mixtures of autochthonous species planted in combined strips, which are the fastest way to provide significant biodiversity benefits within farmed landscapes, enhancing the diversity and abundance of insects, birds, and small mammals, offering resources and reservoirs. This study was carried out in three intensive fruit farms in Spain over a three-year period (2013–2015). Each field was divided into two zones: the margin where a multifunctional margin was planted, and another that remained unchanged in the field. A clear trend to increase RTE species throughout the years in all farms was observed. Moreover, the margin showed a significant difference with respect to the field in the average number of insect species and individuals. The use of margins improves the appearance of RTE species in mean percentages ranging between 12.06 and 25.26% according to the sampling area. Margins also favour the increase in species (148.83–232.84%) and individuals (207.24–586.70%) in agricultural landscapes. These results clearly show that margins are an essential tool to fight insect decline in intensive farming areas.

Connecting neuromodulation, brain development, and life history timing associated with ecological speciation in Rhagoletis pomonella

Host shifts are considered a key generator of insect biodiversity, yet how insects synchronize life history timing and preference for new hosts is not well understood. Neurochemicals such as biogenic amines play key roles in both development and behavior, and therefore provide a potential source for such synchronization. Here, we correlated life history timing, brain development, and corresponding levels of 14 neurochemicals in Rhagoletis pomonella (Diptera: Tephritidae), a species undergoing ecological speciation through an ongoing host shift from hawthorn to apple fruit. We found that adult brain differentiation in both host races was initiated only after pupal diapause ended, and at this stage the titers of precursors for several neurotransmitter pathways also increased significantly. Conversely, neurotransmitter product titres generally increased at later stages up to adult fly sexual maturation. Further analysis showed that the apple host race exhibited adult brain differentiation three weeks earlier than the hawthorn host race, which correlated with significantly lower titers of several neurochemicals, particularly biogenic amines, in the earlier developing apple race as compared to the hawthorn race. We thus propose that these neurotransmitter levels could influence the differences in life history timing and host preference observed in these two races, promoting their ongoing speciation.

Mangroves are an overlooked hotspot of insect diversity despite low plant diversity

Background The world’s fast disappearing mangrove forests have low plant diversity and are often assumed to also have a species-poor insect fauna. We here compare the tropical arthropod fauna across a freshwater swamp and six different forest types (rain-, swamp, dry-coastal, urban, freshwater swamp, mangroves) based on 140,000 barcoded specimens belonging to ca. 8500 species. Results We find that the globally imperiled habitat “mangroves” is an overlooked hotspot for insect diversity. Our study reveals a species-rich mangrove insect fauna (>3000 species in Singapore alone) that is distinct (>50% of species are mangrove-specific) and has high species turnover across Southeast and East Asia. For most habitats, plant diversity is a good predictor of insect diversity, but mangroves are an exception and compensate for a comparatively low number of phytophagous and fungivorous insect species by supporting an unusually rich community of predators whose larvae feed in the productive mudflats. For the remaining tropical habitats, the insect communities have diversity patterns that are largely congruent across guilds. Conclusions The discovery of such a sizeable and distinct insect fauna in a globally threatened habitat underlines how little is known about global insect biodiversity. We here show how such knowledge gaps can be closed quickly with new cost-effective NGS barcoding techniques.

Enhancement of the Diversity of Pollinators and Beneficial Insects in Intensively Managed Vineyards

(1) Modern, intensive agricultural practices have been attributed to the loss of insect biodiversity and abundance in agroecosystems for the last 80 years. The aim of this work is to test whether there are statistically significant differences in insect abundance between different zones and over time on the vineyard field. (2) The study was carried out in five intensive wine farms in Spain over a three-year period (2013–2015). Each field was divided into two zones, one where cover plants were planted, and another remained unchanged (without cover). (3) A clear trend to increase the average number of insect species and individuals throughout the years in all farms was observed. Moreover, the zones with cover plants showed a significant difference with respect to the zones without. (4) The use of permanent cover plants allows creating areas of refuge for the insects favouring their conservation and reducing the agriculture impact in the insect decline.