Nectar Research Articles

Long‐proboscid horseflies (Philoliche: Tabanidae) as pollinators of co‐adapted plants in Africa and Asia

AbstractElongated nectar‐feeding mouthparts have evolved in several fly families, most notably Nemestrinidae, Bombylidae and Tabanidae. Plants pollinated by these “long‐proboscid flies” tend to have relatively specialized pollination systems. In this review, I focus on the blood‐ and nectar‐feeding horsefly genus Philoliche (Tabanidae: Pangoniinae) which includes species that are important pollinators of plants in Africa and, to a lesser extent, in Asia. The nectar‐feeding mouthparts of flower‐visiting Philoliche species range from 5 to 65 mm in length, with considerable intraspecific variation evident in some taxa. Plants pollinated by Philoliche species tend to have corolla tubes (or highly exerted reproductive structures) that match the proboscis dimensions of their pollinators. Some Philoliche species and their nectar host plants show population‐level covariation in proboscis lengths and flower depths that is indicative of co‐adaptation. I summarize existing information on the distribution and morphology of Philoliche species known to pollinate flowers as well as the identity, morphology and nectar properties of plants pollinated by these insects. This survey identifies some Philoliche species as keystone pollinators. Distinct guilds of plants are adapted to different horsefly species in different geographical regions and are generally ecologically reliant on these insects, although some plant species share tabanid and nemestrinid pollinators that are functionally similar on account of convergent evolution of their proboscis dimensions. Lack of information about the larval biology, nectar host plants, fire ecology and dispersal distances of Philoliche species is the biggest challenge for the conservation of these specialized pollinators and the plants that depend on them.

Ants may buffer the Janzen-Connell effect in a tropical forest in Southwest China.

Mutualistic symbioses between ants and plants are widespread in nature. Ants can deter unwanted pests and provide protection for plants in return for food or housing rewards. Using a long-term demographic dataset in a tropical seasonal rain forest in Southwest China, we found that associations with ants positively influenced seedling survival and adult growth, and also, species with extrafloral nectaries experienced weaker conspecific negative density dependence compared with species without extrafloral nectaries. Furthermore, we found strong evidence suggesting that species in our forest experienced conspecific density dependence, which we interpreted as heavy pest pressure that may drive the development of anti-pest symbioses such as the plant-ant relationship. Our findings suggest that ants and conspecific neighbors play important but inverse roles on plant survival and growth and that ants can buffer tree neighborhood interactions in this tropical forest.

Influence of temperature conditions of the environment on the dynamics of collecting bee pollen and flower pollen by honey bees

The study conducted at the apiary of the National Scientific Center «P.I. Prokopovych Institute of Beekeeping» in Hadiach, Poltava region, from 2021 to 2023 investigates the dynamics of bee pollen collecting by honey bees of the Ukrainian steppe breed of the Hadiach type. This research focuses on understanding how weather conditions in the forest-steppe zone impact the mass, volume, and size of bee pollen, as well as the botanical composition of the collected pollen. The primary objective of this research is to analyze how different weather conditions influence the collection of bee pollen by honey bees. Specifically, the study aims to assess how variations in temperature, humidity, and other weather factors affect the quantity and quality of pollen collected, and how these factors interact with the flowering periods of key nectar plants. The study utilized hanging pollen collectors to gather pollen from bee colonies between 8 AM and 2 PM. The botanical origin of the pollen was determined through microscopic analysis and international palynological databases. The research focused on several common nectar plants, including red clover (Trifolium pratense), common primrose (Primula vulgaris), cornflower (Centaurea cyanus), common agrimony (Agrimonia eupatoria), field thistle (Cirsium arvense), and common burdock (Carduus acanthoides). Weather conditions were classified into favorable (temperatures of 18–25°C and relative humidity of 57–72%) and unfavorable (cloudy days with northern winds, temperatures below 15°C or above 28°C, and humidity levels outside the 57–72% range). The research revealed that the average mass of bee pollen collected per season varied between 6.3 and 6.6 kg per bee colony. The study found that different plants responded differently to weather condi­tions. For instance, the mass of pollen from red clover ranged from 8.3 to 12.0 mg under favorable conditions, while field thistle showed a decrease in pollen mass during unfavorable conditions. Pollen collection began in mid-April and continued until mid-August. During unfavorable weather conditions, there was a noticeable reduction in pollen mass, which was attributed to lower pollen availability. However, some plants showed better pollen production under adverse conditions. The spring peak in pollen collection, associated with active colony growth, was also influenced by the less diverse summer flora. Temperature data for 2021–2023 indicated that the most favorable conditions for pollen collection varied annually. For example, the cool spring of 2021 delayed bee colony development, while 2022 experienced normal weather conditions. In contrast, 2023 saw active pollen collection during acacia blooming but a reduction duringlime blooming due to insufficient pollen. The study underscores the importance of considering a comprehensive range of weather conditions when evaluating bee colony productivity. The findings highlight that both temperature and humidity significantly impact pollen collection. The results suggest that beekeepers need to account for these variables in their management practices to optimize pollen collection. Further research should explore the interactions between different weather factors and their combined effects on bee foraging behavior and pollen production. Additionally, studies could investigate how changes in climate over longer periods affect bee colony performance and pollen dynamics, providing insights for developing adaptive strategies in beekeeping.

Comparing Ant Activity and Plants Bearing Extrafloral Nectaries in Rockland Habitats of the Florida Keys with Those of the Everglades and the Bahamas

Rocklands are present in South Florida, both on the peninsula and in the Keys. Previous work has shown that extrafloral nectaries on pine rockland plants in the Florida Everglades and surrounding areas play a role in attracting ant protectors. Species with nectaries are more abundant and ant activity greater in more recently burned pine rockland habitats compared with longer undisturbed rockland hammock forest. The floristic composition and prevailing climate of Keys rocklands differs substantially from those on the mainland, so we sought to investigate ant activity and the abundance of plants with extrafloral nectaries in Big Pine Key rockland habitats. Standard baiting methods were used to assess ant abundance and potential predation activity in hardwood hammock, shrubby pine rockland, and open pine rockland sites. Ant activity was the lowest in open pine rockland, greatest in hardwood hammock, and intermediate in shrubby pine rockland, the opposite of what has been observed in previous studies in southern peninsular Florida and on Andros, Bahamas. Sampling vegetation at these same sites revealed a larger proportion of plant species with extrafloral nectaries in the pine rocklands than the hammock, as observed previously in Everglades habitats. Possible reasons for differences in ant activity in Keys rockland habitats are discussed.

Unravelling the Homology between Calycine Glands in Malpighiales: New Data from Basal Malpighiaceae.

Discussing homology relationships among secretory structures remains a relatively underexplored area in botanical research. These structures are widely dispersed within Malpighiales, one of the largest orders of eudicots. Within Malpighiales, both extranuptial and nuptial nectaries are present, and they do not seem homoplastic or share evolutionary connections. Particularly in Malpighiaceae, extensive research has focused on the ecological interactions mediated by glands. Botanists largely agree that elaiophores in sepals of Neotropical Malpighiaceae have evolved from extrafloral nectaries on leaves. However, the evolutionary origin of elaiophores has yet to be thoroughly examined, particularly in comparison to outgroups. This study provides empirical evidence on the ontogeny of elaiophores and investigates their evolutionary origins and homology relationships across different lineages of Malpighiales using comparative anatomy. Our findings suggest that elaiophores are likely homologous to extranuptial nectaries found in sepals of other Malpighiales lineages, originating from nectaries on leaves. This discussion is a starting point for future studies exploring the evolution of nectaries found in flowers, whether extranuptial or nuptial, and their potential origins from nectaries in vegetative organs such as leaves. Understanding these relationships could shed light on the selective pressures influencing floral morphologies.

A Taxonomic Study of the Genus <i>Cassia</i> Linn. in Rajasthan

Twenty one species of the genus Cassia Linn. (Caesalpiniaceae) occur Rajasthan. The present paper deals with the correct identity, nomenclature and taxonomic status of the taxa. Short diagnostic description of each species has been given along with the ecological notes, local name, flowering and fruiting period, local uses and geographical distribution. More emphasis has been laid on the extra-floral nectaries, number and shape of anthers and on the areole of the seeds. A key for the identification of the taxa is given along with the figures of important plant organs of taxonomic value.

Impact of direct and indirect ingestion of six systemic pesticides on the parasitoid Anagyrus vladimiri

Anagyrus vladimiri (Hymenoptera: Encyrtidae) is the main parasitoid of Planococcus citri (Hemiptera: Pseudococcidae), which is one of the most important pests of citrus crops in the Mediterranean Basin. Pesticide residue on trees and in the nectar of wildflowers growing in citrus orchards might cause side effects in beneficial insects. In the present study, we assessed the effects of six systemic pesticides (acetamiprid, dimethoate, cyantraniliprole, flupyradifurone, spirotetramat and sulfoxaflor) on the survival and progeny of A. vladimiri. Anagyrus vladimiri fed on the pesticide solutions and on the nectar of Fagopyrum esculentum Moench plants that had been watered with a solution containing these pesticides. Acetamiprid, dimethoate, flupyradifurone and sulfoxaflor increased female mortality more than the control (water) after 6h; after A. vladimiri consumed these pesticides, female mortality ranged from 62% to 73%. Cyantraniliprole had no immediate toxic effect on parasitoid survival but caused mortality after 15 days. All tested pesticides except flupyradifurone and spirotetramat reduced parasitoid progeny. After six days of feeding on F. esculentum nectar of plants watered with a pesticide solution, significantly increased female mortality was observed with dimethoate (96%), spirotetramat (80%), acetamiprid (62%), cyantraniliprole (62%) and sulfoxaflor (50%). Progeny was reduced in females that fed on plants treated with spirotetramat and dimethoate. These results demonstrate that some of these insecticides can have lethal or sublethal effects on A. vladimiri by both routes of exposure, via direct or indirect pesticide consumption through the nectar of treated plants.

A knot of hybrids: Differentiating Asian knotweeds in North‐Eastern France using genetic, cytological, and morphological data

AbstractThe two invasive Reynoutria species, Reynoutria japonica var. japonica and Reynoutria sachalinensis, and their hybrid Reynoutria x bohemica are often misidentified by managers and nonspecialists. The taxonomic confusions are all the more exacerbated by the infraspecific variability of introduced populations in terms of morphology, genetic diversity, and ploidy level. We resolved the identity of North‐Eastern French invasive populations using 4582 single‐nucleotide polymorphisms (SNPs) from a RADseq analysis, DNA contents estimated by flow cytometry, and 12 vegetative morphometric variables. The SNPs supported only one single genotype for R. japonica over 11 localities, while the nine localities of Reynoutria x bohemica were represented by one genotype each. Estimation of genome size using DAPI staining and flow cytometry revealed only octoploid cytotypes for R. japonica and hexaploid cytotypes for R. x bohemica, whereas R. sachalinensis was represented by tetraploid and hexaploid cytotypes. Among morphometric variables, no single one allows for a clear differentiation of the three taxa. We propose a combination of characters to easily and quickly identify these three invasive taxa based on six vegetative criteria including leaf and apex length, as well as leaf shape, leaf base, and apex shape, and the extrafloral nectaries on the node.

Effect of faba bean nectar on longevity and fecundity of Plutella xylostella and its parasitoid Cotesia vestalis

Intercropping faba bean with vegetables provides a possibility to promote pest control and better nutrient cycling in sustainable agriculture. Faba bean produces extrafloral nectar which supports parasitoid wasps that play a role in the biological control of pest insects. However, adult lepidopteran pests also benefit from nectar, increasing their lifespan and the number of offspring they produce. Here, a laboratory-based study was conducted to assess the role of faba bean on the components of a Brassica-based host-parasitoid system. We measured how access to faba bean affected the longevity and fecundity of the brassica pest Plutella xylostella and its parasitoid Cotesia vestalis. It was also studied if odors of flowering faba bean disrupt host finding by C. vestalis in Y-tube bioassays and volatile organic compounds were analyzed to explain the olfaction-based choices made by the parasitoids. The longevity of C. vestalis was 6.6 times longer and the number of pupae produced almost 10 times greater when they had access to faba bean. Meanwhile, the longevity of P. xylostella was 3.6 times longer and it laid 4.6 times more eggs when provided access to faba bean. In Y-tube bioassays, C. vestalis females also oriented toward host-related odors of the damaged cabbage more than intact cabbage when odors of faba bean were mixed with both of them. In conclusion, faba bean provided sustenance to both pest insects and their natural enemies that prolonged their lifespans and their reproductive capacity.

Diel activity patterns of a canopy-inhibiting beetle community (Coleoptera) in a Neotropical rainforest

Diel activity is one main feature of animal‘s behavior and is often an intrinsic trait characterizing distinct taxonomic groups. Abiotic conditions such as temperature may influence the diel activity patterns of arthropod communities associated with a particular ecosystem or habitat. Similarly, biotic factors, such as resource availability, affect arthropod activity. In addition, diel activity is thought to be an important factor in niche partitioning of arthropod communities. As part of a larger beetle survey in a lowland tropical rainforest in southern Venezuela, I analyzed the diel activity of an arboreal beetle community collected from 23 canopy-tree species over a cumulative year. Diel activity was observed in 535 beetle species, comprising 5,948 individuals, using a canopy crane installed in the study area. Of the 535 beetle species, 198 (37%) showed diurnal activity, and 281 (52.5%) showed nocturnal activity. In contrast, the proportions of nocturnal (n = 2,024, 34%) and diurnal (n = 1,983, 33.3%) individuals were balanced. Most of the observed beetles occurred only during the activity phase in their host trees. This particularly applies to extrafloral nectary- and flower-visiting beetle species. Flowering trees attracted different proportions of diurnal and nocturnal species according to flowering syndrome, whereas extrafloral nectaries were mainly visited at night. Thus, the beetle communities associated with single tree species showed distinct compositions of nocturnal and diurnal species.

Foraging ants affect community composition and diversity of phyllosphere fungi on a myrmecophilous plants, Mallotus japonicus.

Many microorganisms inhabit the aboveground parts of plants (i.e. the phyllosphere), which mainly comprise leaves. Understanding the structure of phyllosphere microbial communities and their drivers is important because they influence host plant fitness and ecosystem functions. Despite the high prevalence of ant-plant associations, few studies have used quantitative community data to investigate the effects of ants on phyllosphere microbial communities. In the present study, we investigated the effects of ants on the phyllosphere fungal communities of Mallotus japonicus using high-throughput sequencing. Mallotus japonicus is a myrmecophilous plants that bears extrafloral nectaries, attracting several ant species, but does not provide specific ant species with nest sites like myrmecophytes do. We experimentally excluded ants with sticky resins from the target plants and collected leaf discs to extract fungal DNA. The ribosomal DNA internal transcribed spacer 1 (ITS1) regions of the phyllosphere fungi were amplified and sequenced to obtain fungal community data. Our results showed that the exclusion of ants changed the phyllosphere fungal community composition; however, the effect of ants on OTU richness was not clear. These results indicate that ants can change the community of phyllosphere fungi, even if the plant is not a myrmecophyte.

Conservation of natural enemies of Diaphorina citri and their impact on Huanglongbing: Analysis and perspectives

Diaphorina citri is the main vector of Candidatus Liberibacter asiaticus (CLas), the causative agent of HLB, the most devastating citrus disease. Although the importance of biological control is recognized, insecticides are the main control tool used. Its use in citrus should be cautious, as it could interfere with the biocontrol of exotic pests already present. Diaphorina citri has a wide range of natural enemies; however, only the parasitoid Tamarixia radiata and some species of entomopathogenic fungi are used inundatively. Although the main predators of the vector occur naturally, few studies address their conservation in situ. This review supports the idea that the conservation of natural enemies should be the basis of the integrated management of D. citri and CLas. The conservation of alternate hosts, the inclusion of nectar plants, in situ conservation of parasitoids, and the autodissemination of entomopathogenic fungi are proposed. Studies carried out on conservation of natural enemies of D. citri and related pests, their probable impact on the disease, and prospects for implementation in Mexico are analyzed and discussed. The proposed strategies could enhance not only the biological control of D. citri-CLas, but also the autoregulation of citrus pests in general.

Pollination Syndrome, Florivory, and Breeding System of Satyrium nepalense var. ciliatum (Orchidaceae) in Central Yunnan, China.

Research on Satyrium nepalense var. ciliatum (Lindl.) Hook. f. has primarily focused on populations in Northwestern Yunnan, with limited studies on pollination syndromes and insect behavior. In addition, it is geographically limited in its breeding system studies. Here, pollination syndromes, florivory, and breeding systems of S. nepalense var. ciliatum from Liangwang Mountain (Central Yunnan, China) were investigated through field work, microscope, scanning electron microscope (SEM), and parafin section. It was revealed that the pollination syndrome was possessing out-crossing, such as bright color, a developed rostellum, nectar glands in the spur, and food hairs at the lip base. The color and nectar attracted flower visitors, and florivory was observed. Some flower visitors pollinated their companion species. Ants were identified as floral visitors for the first time in Satyrium, although substantial pollination was not observed. Ants might be potential pollinators. S. nepalense var. ciliatum possessed a mixed breeding system, including selfing, out-crossing, and apomixis, with apomixis being predominant in nature. It is suggested that the pollination syndrome, florivory, and pollination competition would contribute to its mixed breeding systems, particularly leading to the occurrence of apomixis.

Marketing research of honey consumer preferences in the markets of Kostanay region

Bee honey is a valuable, multicomponent unique product produced by bees from the nectar of honey plants. In the human diet, honey is an alternative to sugar and sugar-containing foods as a healthier food product.
 Within the framework of this article, a marketing study and analysis of preferences among consumers of honey and other bee products among residents of Kostanay and the region were conducted.
 Today, about 50% of honey is produced in China, Argentina, the USA, Ukraine, Turkey, and Russia. Honey exporting countries are characterized by flexible economic and organizational interaction. The main role is played by the mechanisms of legal protection and the developed infrastructure of the industry, which ensures full-fledged work, sales of products, and the receipt of foreign exchange earnings to the country's budget.
 The materials of this article contain an analysis of the types of bee products consumed, quality criteria when choosing honey, other bee products, as well as factors determining the choice of consumers. Also, the priorities of the origin of honey (apiaries) have been determined among consumers.
 The study grouped the key characteristics of honey consumers in the areas of Kostanay region that affect their behavior, desires and preferences. By quantitative analysis of the results of the survey of the target audience, an average portrait of buyers of honey and other bee products has been compiled, which can be used by entrepreneurs at all stages of planning and promoting their products.
 A literary review of the state of knowledge of this issue was conducted, citing articles from domestic and foreign sources.
 The results obtained can be used by domestic producers in the development and optimization of a strategy for promoting bee products.

Analysis of Free Amino Acid Composition and Honey Plant Species in Seven Honey Species in China.

Honey is well-known as a food product that is rich in active ingredients and is very popular among consumers. Free amino acids (FAAs) are one of the important nutritional components of honey, which can be used not only as a nutritional indicator of honey but also as an indicator of plant source identification. In this study, the contents of 20 FAAs in seven types of honey from 11 provinces in China were examined for the first time. The 20 FAAs were analyzed by ultra-performance liquid chromatography-mass spectrometry/mass spectrometry (UPLC-MS/MS). By analyzing 93 honey samples from seven types of honey, the FAAs were found to range from 394.4 mg/kg (linden honey) to 1771.7 mg/kg (chaste honey). Proline ranged from 274.55 to 572.48 mg/kg, and methionine was only present in some of the linden honey, chaste honey, acacia honey, and rape honey. Evaluated by amino acid principal component analysis, multifloral grassland honey had the highest overall evaluation score, acacia and jujube honey were the most similar, while chaste honey was the least similar to the other types of honey. In addition, DNA was extracted from 174 Xinjiang grassland honey samples and different plant leaves for PCR and sequencing to identify the species of nectar plants. As a result, 12 families and 25 species of honey plants were identified. The results confirmed the diversity of FAAs in dissimilar types and sources of honey. This study provides a reference for expanding honey quality standards and verifying the authenticity of honey.

Beekeeping Behavior of Chinese Beekeepers Shows Spatial Contraction

Apiculture is an important industry closely related to the national economy and people’s livelihoods. Beekeepers’ behavior is an important factor affecting the yield, quality, and benefits of apiculture. However, there is a lack of a systematic understanding of the long-term changes in beekeeping decisions made by beekeepers. Using panel data, we analyzed the dynamic trends and related influencing factors of decisions made by beekeeping models, honey source plant selection, and the migration flow space of beekeepers from 2009 to 2020. The results showed that the proportion of the LMB model decreased, while the PAB and SMB models continued to increase, the frequency of utilization of the main nectar source plants for honey collection decreased, and the concentration of migratory flow of beekeeping increased. Behavior of beekeepers from 2009 to 2020 showed a certain degree of spatial contraction, which seriously restricted the effective use of nectar plant resources. Family attributes, economic status, beekeeping models, and disaster conditions directly or indirectly affected beekeepers’ decisions. We propose a series of recommendations to facilitate the transformation and advancement of the Chinese bee industry. This study promotes an understanding of sustainable development of the bee industry in China and other countries worldwide.

A phosphatase gene is linked to nectar dihydroxyacetone accumulation in mānuka (Leptospermum scoparium).

Floral nectar composition beyond common sugars shows great diversity but contributing genetic factors are generally unknown. Mānuka (Leptospermum scoparium) is renowned for the antimicrobial compound methylglyoxal in its derived honey, which originates from the precursor, dihydroxyacetone (DHA), accumulating in the nectar. Although this nectar trait is highly variable, genetic contribution to the trait is unclear. Therefore, we investigated key gene(s) and genomic regions underpinning this trait. We used RNAseq analysis to identify nectary-associated genes differentially expressed between high and low nectar DHA genotypes. We also used a mānuka high-density linkage map and quantitative trait loci (QTL) mapping population, supported by an improved genome assembly, to reveal genetic regions associated with nectar DHA content. Expression and QTL analyses both pointed to the involvement of a phosphatase gene, LsSgpp2. The expression pattern of LsSgpp2 correlated with nectar DHA accumulation, and it co-located with a QTL on chromosome 4. The identification of three QTLs, some of the first reported for a plant nectar trait, indicates polygenic control of DHA content. We have established plant genetics as a key influence on DHA accumulation. The data suggest the hypothesis of LsSGPP2 releasing DHA from DHA-phosphate and variability in LsSgpp2 gene expression contributing to the trait variability.

Effects of Various Nectar and Pollen Plants on the Survival, Reproduction, and Predation of Neoseiulus bicaudus.

Neoseiulus bicaudus is a predatory mite species that could potentially be used for the biological control of spider mites and thrips. Floral resources can provide excellent habitats and abundant nutrients for natural enemies. The objective of this experiment was to evaluate the effects of eight floral resources on the longevity, fecundity, and predation ability of N. bicaudus. Among the considered plants, Cnidium monnieri led to the highest longevity (24 days) and fecundity (13.8 eggs) of N. bicaudus, while Tagetes erecta resulted in the lowest longevity (7 days) and fecundity (0.1 eggs) observed in the predatory mites. By comparing the effects of three nectar and pollen plants on the predation of predatory mites, it was observed that N. bicaudus still exhibited a type II functional response to Tetranychus turkestani. In the presence of pollen, the predation efficacy (a/Th) of N. bicaudus exhibited a lower value, compared to that in the absence of pollen (Control: a/Th = 24.00). When pollen was supplied, the maximum consumption (1/Th) of predatory mites was higher than in its absence (Control: 1/Th = 9.90 d-1), with the highest value obtained in the presence of B. officinalis pollen (B. officinalis: 1/Th = 17.86 d-1). The influence coefficient of predation of N. bicaudus on T. turkestani in the presence of pollen was compared in the presence of three nectar and pollen plants: Cnidium monnieri, Centaurea cyanus, and Borago officinalis. At low prey densities, the influence coefficient of C. cyanus exceeded that of B. officinalis, and the overall influence coefficient values were negative (i.e., the presence of pollen reduced predatory mite feeding on T. turkestani). They exhibited similar values at high prey densities, and all of the influence coefficient values were close to 0 (i.e., the presence of pollen had no effect on predatory mite feeding on T. turkestani). The findings revealed that diverse plant species exert differential impacts on N. bicaudus, with some influencing its lifespan and others affecting its reproductive capabilities. Furthermore, the presence of nectar and pollen plants had a significant impact on predatory mite feeding on T. turkestani at low prey densities; however, this effect diminished as the prey density increased. Therefore, we recommend planting C. monnieri, C. cyanus, and B. officinalis in the field to ensure an ample population of predatory mites. The obtained results hold significant implications for the utilization of nectar and pollen plants in eco-friendly pest management strategies within agricultural contexts.

Wildlife-friendly garden practices increase butterfly abundance and species richness in urban and arable landscapes

Insect declines are being reported worldwide and private, residential gardens could provide refugia for these species under increasing land use change. Interest in wildlife-friendly gardening has increased, but many management recommendations lack a scientific evidence-base. We used a large citizen science scheme, the Garden Butterfly Survey (GBS), with data from over 600 gardens across Great Britain (2016–2021) to determine how the surrounding landscape influences the abundance and species richness of butterflies in gardens and whether wildlife-friendly gardening practices, such as having long grass and providing nectar plants, benefit butterflies. First, we show that GBS provides reliable estimates of species abundances by comparing with results from standardised, long-term monitoring data. Garden size and surrounding land use had significant effects on butterfly abundance and richness in gardens, including positive relationships with garden size, woodland and arable farmland and negative relationships with urbanisation. Both the presence and area of long grass in gardens were positively related to higher butterfly richness and abundance, with the latter being driven by butterflies that use grasses as larval host plants. These effects differed depending on the surrounding landscape, such that long grass resulted in higher garden butterfly abundance in landscapes dominated by arable farming, and higher abundance and richness in highly urbanised areas. The presence of flowering ivy (Hedera spp.) in gardens resulted in higher abundance of Celastrina argiolus holly blue which uses ivy as a larval host, and of Vanessa atalanta red admiral and Polygonia c-album comma, which favour it as a nectar source. Our work provides evidence that undertaking simple wildlife-friendly garden practices can be beneficial for attracting butterflies, particularly in heavily modified areas. With over 728,000 ha of gardens in Great Britain, the cumulative effect of leaving areas of lawn uncut and providing nectar and larval host plants could be key for helping biodiversity.

Modelling foraging strategies of honey bees as agents in a dynamic landscape representation

Introduction: Both intrinsic colony mechanisms and external environmental variables affect the honey bee colony development rates and response and a key aspect of this is the use of resources within the landscape by honey bees. Although several models have been developed to explore the foraging behaviour of bees, none fully considered the spatial and temporal dynamics of landscape resources and the role of the colony in the process. Methodology: Here, we introduce a new honey bee foraging model being developed as a part of the ApisRAM honey bee colony model. Based on agent-based modelling, we used a dynamic ALMaSS landscape model enhanced with floral resource modelling to assess the impacts of weather conditions and resource availability on the possible foraging behaviour of honey bees. Several possible mechanisms (defined, based on honey bee traits) for scouting and foraging were investigated, separately for nectar and pollen collection, including prioritising foraging polygons for nectar foraging according to their distance to the colony, the quality or the energetic efficiency and, for pollen foraging, according to their distance to the colony and pollen quantity. Results: If model foraging bees prioritised the polygons, based on their distance from the colony, the number of unsuccessful flights increased compared to other tested strategies and the total amount of sugar collected showed a high variability. Contrary to expectations, the energetic efficiency strategy did not provide the colony with the highest amount of sugar. Overall, the tested strategies provide different outcomes on the collection of resources, the number of performed flights and their success rate, evidencing that the model's outcome at the colony level arises from the individual types of behaviour. Conclusions and Relevance: Variability in the mass of collected nectar and pollen was found mostly when scout bees applied the distance strategy. This higher variability in sugar collection means that model bees were not able to find the most profitable foraging sites at the landscape level, but only at the local level. Other strategies showed less dependence on the surrounding landscape (i.e. quality or random), but it comes at a cost (i.e. lower production for both nectar and pollen collection). These outputs help us evaluate which strategies could be used for future model development and confirm the models' ability to create dynamic responses. These responses at the colony level were only possible thanks to the implementation of a dynamic landscape model and dynamic spatiotemporal resource model, as well as implementing a social communication mechanism for bees to share information about the resources. Plant nectar production and quality information is essential to predict honey bee foraging distribution. In future model development, the implementation of pollen quality should also be explored to evaluate if it influences the overall pollen collection.