Anthony P. Abbate

The cotton aphid Aphis gossypii Glover is a pest of cotton Gossypium hirsutum L. in the southeastern United States, capable of direct feeding damage and as a vector of plant viruses. Dispersal activity in agroecosystems can be monitored passively with the use of colored pan traps. The unintended bycatch of Hymenoptera was noted in these traps during an approximately 1-mo span during the peak blooming period in 2021 and 2022. While native pollinators have been receiving recent attention due to their benefits to crops, native bees in Alabama have not yet been investigated on cotton. Adjacent states such as Georgia, Mississippi, and Texas have recorded the benefits of Hymenoptera species to cotton pollination, showing increased lint and seed yield and projecting potential gains to profits for growers. We identified the Hymenopteran species captured as bycatch in yellow pan traps, recording 66 species/species complexes in 4 families. Twenty-two of these species were recorded as cotton pollinators in other states, and 4 species were new or possibly new species records for the state. Our results show that bycatch can be a feasible method to document native bee pollinators and support future research into the idea that cotton may have the potential to provide resources to native bees in agroecosystems.

Eusocial insect colonies can choose different behaviours to combat the same parasites. While honeybee (HB), Apis mellifera , colonies remove eggs and larvae of parasitic small hive beetles (SHB), Aethina tumida , they encapsulate adults in propolis. It is currently unknown whether there is flexibility in this system. Here, we show encapsulation of eggs by colonies as an alternative to removal. Oviposition sites with or without SHB eggs were introduced into HB field colonies of mixed European origin. After 24 h, sites were removed to measure the propolised area and to quantify the remaining eggs. Further, SHB egg laying depth, and HB worker proboscis length and thickness, were measured. Even though the proboscises were long enough to reach most eggs, the number of eggs before and after introduction did not differ. Instead, HB used more propolis on sites with eggs compared to controls. This suggests decision making by colonies for either egg removal or encapsulation and demonstrates considerable flexibility in social immunity. Such flexibility probably contributes to eusocial insect resilience and calls for efforts to understand colony decision making.

Pollination services provided by native bees are vital to the success of flowering plants in agricultural production and natural ecosystems. There are concerns that many native bee species are in decline due to multiple concurrent factors stemming from practices adopted by industrial agricultural production systems, such as the loss of suitable habitat, lack of floral resources and pesticide exposure. Most bee species in North America rear their offspring below ground and are potentially vulnerable to soil management activities, such as tillage operations in row crop settings. We investigated the effects of tillage on ground‐nesting bees in a row crop system by intensively sampling bees nesting within treatments representative of standard tillage practices employed in the Southeastern United States. Our study is among the first to investigate how tillage regimes shape entire bee assemblages in intensively managed US croplands; by contrast, most previous research has focused almost exclusively on the squash bee, Eucera (Peponapis) pruinosa (Say, 1837), and has produced mixed results We found strong evidence that ground‐nesting bee incidence, abundance and diversity declined to varying degrees in all tilled treatments compared to field edges. Clarifying whether tilled fields act as ecological sinks or are simply avoided as unsuitable habitat will be critical for guiding conservation efforts that prioritise the preservation and enhancement of semi‐natural margins in agricultural landscapes.

Bees are highly effective pollinators facing declines. We need a better understanding of our existing native bee assemblages to preserve them. Recent studies have shown that bee assemblages are vertically stratified in forested habitats, but our understanding of how that translates to the southeastern United States is lacking. Most of our knowledge is restricted to how bees utilize the forest understory, potentially biasing monitoring efforts. We sampled and compared the bee assemblages of a temperate deciduous forest (Tuskegee National Forest, Tuskegee, Alabama, USA) in the canopy and understory from April-September 2021 and March-October 2022. Blue vane traps were deployed at four sites across Tuskegee National Forest with four replicates per site. Each replicate had a blue vane in the understory (1 m) and in the upper canopy (20 m average). In total, we captured 1,494 bees representing 37 taxa belonging to 15 genera and 5 families (Andrenidae, Apidae, Colletidae, Halictidae, and Megachilidae). Abundance varied seasonally and by year. There were just over two times as many bees in the canopy as in the understory. The four most commonly captured species ( Lasioglossum bruneri , Melissodes bimaculatus , Augochlora pura , and Bombus impatiens ) were present in significantly higher abundances in the canopy. We found no significant differences in species richness between the two strata but found that Simpson Diversity was significantly different. Interestingly, in 2021 Simpson Diversity was higher in the canopy, while in 2022 it was higher in the understory. Based on our findings, we suggest multi-year, multi-strata sampling when surveying for bees in forested environments.

The diversity of plants and their animal pollinators is in decline due to anthropogenic pressures such as habitat loss, pesticide use, and agricultural intensification. Approximately 78% of angiosperms rely on animal‐mediated pollination, yet data on the pollination biology of many native wildflower species is lacking. We investigated the pollination biology of eight wildflower species native to the southeastern United States, including Bidens laevis, Desmanthus illinoensis, Echinacea purpurea, Eryngium yuccifolium, Gaillardia pulchella, Monarda punctata, Verbesina alternifolia, and Verbesina virginica, which are either recommended by the USDA—Natural Resource Conservation Service or the Xerces Society to enhance native pollinator habitat. We evaluated each species' dependence on insect pollinators through an insect exclusion experiment and documented insect floral visitors via sweep netting surveys followed by a plant‐pollinator network analysis. For most species, open‐pollinated inflorescences produced significantly more and/or heavier seeds per inflorescence compared to those excluded from insect visitors, indicating a high degree of pollinator influence. In comparison, several species exhibited potential for self‐pollination. A total of 1417 insects, representing 73 genera/species from 21 families and 4 orders, were observed visiting the wildflower species. These findings indicate the importance of insect pollinators for maximizing seed production and quality in these native wildflower species and underscore the importance of considering the pollination requirements when selecting species for conservation plantings. Our results highlight that some native wildflower species reproduce and set seed in the absence of pollinators, making them valuable for providing floral resources in degraded habitats, while strongly pollinator‐dependent species may be better suited for conservation plantings in areas with robust or recovering pollinator communities.

Here we provide a comprehensive description of the Auburn University Native Bee Lab’s outreach collection and its role in the lab’s broader outreach program. We outline the mission and goals of the Native Bee Lab, detailing how the outreach drawers are implemented to support public education and promote pollinator conservation. We include a thorough overview of the specific taxa within the outreach collection and explain how these specimens are used to address common misconceptions about bees, educate the public on bee biology and natural history, and highlight bee biodiversity. Additionally, we classify the variety of outreach events the lab hosts and participates in, emphasizing the broader impacts of the lab’s efforts. Special attention is given to how insect collections, such as those used by the Native Bee Lab, serve as valuable tools for connecting communities, enhancing science education, and advancing conservation initiatives.

DNA analysis of environmental samples (eDNA) provides a non-intrusive approach to identify organisms, characterize biological communities, and assess biodiversity, including the detection and monitoring of invasive plant effects. However, the use of eDNA for specific applications, such as targeted-species detection, geographic and floral source tracing, and assessment of invasive plant ecological and environmental effects, requires the development of species-specific genetic primers. Chinese tallow (Triadica sebifera (L.) Small) is a non-native high-impact invader, capable of changing fire regimes, native biodiversity, nutrient cycling, and wildlife habitat and populations, that is expanding in range and abundance throughout the southern United States. In this study, we investigated and identified specific genetic sites, markers, in the tallow chloroplast genome and developed sets of primers for tallow eDNA detection. Two sets of tallow primers were developed, tallow-specific primers and tallow-related primers. Both sets of primers can be used for tallow eDNA detection, with higher target specificity for tallow-specific primers. Primers were subsequently validated for target specificity against closely related species, samples of tallow tissue, and honey and honey bee-collected pollen from areas with tallow. We found that tallow-specific primers differentiated tallow eDNA from closely related species, demonstrating target specificity. Furthermore, a sequence analysis of the tallow-related primers in the polymerase chain reaction accurately distinguished members of the Hippomaninae subtribe, including tallow, from other subtribe or subfamily members within the Euphorbiaceae. Ultimately, the genetic markers and the corresponding sets of primers will facilitate eDNA analysis of tallow for several applications, including detection and monitoring in water and soil, assurance of honey quality and floral source tracing, and perhaps serving as a model for determining plant use by pollinators.

Habitat loss, agricultural intensification, pesticide use, disease and climate change have contributed to the decline of numerous insect groups. Recent government initiatives have recognized the importance of supplementary wildflower plantings to support native bee populations, yet little information exists on the attractiveness of recommended plant species to bees. With the use of network analysis and generalized linear mixed models, we evaluated the attractiveness of 18 wildflower species belonging to 6 families (Apiaceae, Apocynaceae, Asteraceae, Fabaceae, Lamiaceae and Verbenaceae) planted in a randomized block design by conducting timed targeted sweep netting surveys. We also evaluated the floral preferences of four bee species (Apis mellifera, Halictus poeyi/ligatus, Bombus griseocollis and Bombus impatiens) to the planted wildflower species with the use of GLMs. We found that Asclepias tuberosa, Gaillardia pulchella and Verbena hastata attracted the greatest abundance, richness and diversity of native bees compared to the other wildflower species. Collectively, Asclepias tuberosa, Gaillardia pulchella and Verbena hastata attracted 89% of all bee taxa in the study, which exemplifies the importance of including them in a wildflower mixture to attract native bees. While several wildflower species attracted low abundance, richness and diversity of native bees such as Monarda fistulosa, Symphyotrichum pilosum and Eryngium yuccifolium, they are still ecologically important for attracting uncommon or specialist bee species and should be included in seed mixes for this reason. Solution. Our results highlight that each species of native wildflower varies in the abundance, richness and diversity of native bees they attract; this could be considered in the decision‐making of landowners and land managers to promote wildflower plantings to reflect the needs of certain groups of bees of conservation interest.

Due to a lack of knowledge on the pollination requirements of kiwifruit cultivars grown within the United States, farmers simultaneously implement multiple pollination methods, like the rental of managed bee species or artificial pollination to achieve high fruit yields. However, implementing multiple pollination methods is costly and possibly an inefficient use of resources. We assessed the contribution of two managed bees (Apis mellifera and Bombus impatiens) to the pollination of kiwifruit by i) determining the relative abundance of kiwifruit pollen collected by foragers of each bee species, and ii) comparing fruit set and fruit quality among insect and artificially pollinated flowers through an insect exclusion experiment. A significant difference was observed between the mean relative abundance of kiwifruit pollen carried in the corbicula of A. mellifera and B. impatiens, with B. impatiens carrying on average 46% more kiwifruit pollen than A. mellifera. Artificially pollinated kiwifruit flowers set significantly greater numbers of fruit per flower at four weeks post-bloom and at harvest compared to insect pollination, wind pollination, and pollen exclusion treatment. Artificial pollination produced fruits of greater weight, size, and seed number compared to insect-pollinated flowers, and few fruits were produced in the pollen exclusion and wind pollination treatments. Kiwifruit producers experiencing similar conditions to ours should focus on artificially pollinating their crops rather than relying on managed or wild insects for kiwifruit pollination. Future research should evaluate other methods of artificial pollination to determine their effectiveness, efficiency, and economics in the pollination of kiwifruit grown within the United States.