Pollinator Declines Research Articles

Biocultural Diversity Loss: the Decline of Native Stingless Bees (Apidae: Meliponini) and Local Ecological Knowledge in Michoacán, Western México

Local ecological knowledge (LEK) is of utmost importance for biodiversity conservation; however, a number of studies document the loss of LEK regarding native bees. Stingless bees (Apidae: Meliponini) are important pollinators that have been managed by humans in all tropical areas of the world. Our work documents the decline of Meliponini and associated LEK in the state of Michoacan, western Mexico, as well as local historical management and perceptions of the diversity and abundance of bees. Through ecological sampling, semi-structured interviews, and participant observation, we established the presence of 13 species of Meliponini and recognition of 23 local names. Although stingless bees’ pot-honey is harvested directly through extraction of wild nests, local knowledge about bee diversity, behavior, and use can contribute to their conservation. Because of recent access to manufactured products and the scarcity of wild nests, LEK and pot-honey harvest are being abandoned and forgotten in some areas. Maintaining LEK is important in designing sustainable use strategies to prevent the extinction of wild nests and allow conservation of bees as well as the cultural legacy associated with them, essential in the context of a global decline of pollinators.

Decline of pollinators and attractiveness of the plants

Flowering plants rely mostly on pollinators to reproduce. A decline of pollinators puts an evolutionary pressure on the allocation of plants’ resources towards attracting the few remaining pollinators. This may result in fewer resources available for the plants’ survival and actual seed production. Moreover, due to the “magnet effect”, attractive plants generally attract pollinators to all plants in their neighborhood, even the less attractive ones. To better understand the allocation trade-offs, we built a computer simulation and studied the evolution of resource allocation towards attracting pollinators. We observed that when pollinators are relatively abundant, there is not much incentive for the plants to allocate more energy to attract them. Only when pollinators are below a certain critical threshold is a relatively large investment in attracting the pollinators suddenly favored. The value of the critical threshold is quite low and further decreases with the increasing seed dispersal distance and the plant population size.

Small-sized protected areas contribute more per unit area to tropical crop pollination than large protected areas

Land-use change is considered one of the main causes of the observed population decline of pollinators. Pollinators are essential for the reproduction of wild and cultivated plant species. Protected areas contribute to pollinator conservation by providing key nesting and foraging habitats. We estimate how much of the pantropical pollination service is currently within terrestrial protected areas. We used publicly available global datasets to generate variables known to predict pollinator abundance and have built a pantropical spatially explicit model of the pollination service. Our results suggest that 80% of tropical protected areas contribute to crop pollination. Protected areas (PAs) that currently do not contribute to crop pollination may contribute in the future as agriculturalisation continues and they begin to neighbour croplands. The remaining PAs provide habitat for pollinators of wild plants, alongside many other ecosystem services. Small-sized PAs provide higher pollination service per unit area than large ones due to their greater proximity to crops in general and their greater perimeter per unit area. These small PAs also tend to be under greater anthropogenic pressure than large-sized tropical PAs. We suggest the role of pollination services to croplands from PAs be considered alongside other ecosystem services in PA management decisions.

Pollinator Specific Richness and Their Interactions With Local Plant Species: 10 Years of Sampling in Mediterranean Habitats.

In the context of global pollinator decline, little is known about the protection status and ecology of many species. This lack of knowledge is particularly important for Mediterranean protected areas that harbor diverse pollinator communities and are subject to considerable anthropogenic pressures. Calanques National Park (85 km2), which is located near Marseille (France), is dominated by Mediterranean low-vegetation habitats, such as phrygana and scrublands. These habitats offer favorable conditions for pollinator species due to the important amount of floral resources. Within a 10-yr period, we recorded bee (Hymenoptera: Apoidea: Anthophila), hover fly (Diptera: Syrphidae), and bee fly (Diptera: Bombyliidae) species and their interactions with the local flora through 10 field campaigns. We caught 250 pollinator species, including 192 bees, 38 hover flies, and 20 bee flies, for a total of 2,770 specimens. We recorded seven threatened bees (six near threatened and one endangered). Among the bee species, 47.9% were below-ground nesting species, and 54.7% were generalist species. Analysis of the pollination network showed that generalist and specialist pollinators do not share the same floral resources. The Cistaceae plant family (Malvales: Cistaceae) acted as a central node in the plant-pollinator network, interacting with 52 different pollinator species, which shows the importance of large open flowers that could be easily visited by both short and long-tongued pollinators in Mediterranean habitats. The occurrence of pollinator species and their ecological traits should strongly contribute to reinforcing the available information to provide or ameliorate the conservation statuses determined by IUCN Red List.

Temperate agroforestry systems provide greater pollination service than monoculture

Insect pollination is a globally important ecosystem service, contributing to crop yields, production stability and the maintenance of wild plant populations. Ironically, agriculture is one of the major global drivers of wild insect pollinator decline. At the same time, increasing human population is driving ever greater demands on crop production. Agroforestry (AF) – a more diverse farming system integrating woody and agricultural crops – can theoretically reconcile high production with provision of ecosystem services such as pollination. However, empirical studies of pollination in temperate AF systems are almost entirely lacking. We sought to fill this knowledge gap by assessing whether AF can provide increased pollination service compared to monoculture (MC) systems. Six UK sites, each containing an AF and a MC system, were studied over three years. Wild pollinator abundance and diversity were used as proxies for the magnitude and stability, respectively, of the pollinating community. We also directly measured pollination service as seed set in a wild plant phytometer. We found that temperate AF systems can provide greater pollination service than MC: AF treatments had twice as many solitary bees and hoverflies, and in arable systems 2.4 times more bumblebees, than MC treatments. AF also had 4.5 times more seed set compared to MC in one of the two years. At 40% of site-by-year sampling units, species richness of solitary bees was on average 10.5 times higher in AF treatments. This provides evidence in favour of the expectation that AF systems can support higher pollinator richness, and therefore greater potential stability, of pollination service. For the other sampling units, and for bumblebees (Bombus spp.), there was no treatment effect on species richness. Further work is needed to investigate the effect of AF on species richness and its mechanistic basis. Our results also highlight the importance of AF system design, ensuring that ecosystem services outcomes are explicitly planned at the design stage. We suggest that AF has a role to play in improving the sustainability of modern farming and in mitigating the ongoing loss of wild pollinating insects, which is strongly driven by prevailing agricultural practices.

Primary pre-service teachers’ emotions and interest towards insects: an explorative case study

ABSTRACT This paper addresses an explorative case study on Spanish primary pre-service teachers’ (PSTs) emotions about, and their interest in, insects. The study is part of a teachers’ training programme on insects and the problem of the decline in pollinators conducted at the University of Santiago de Compostela, using scientific practice-based learning approach. The research questions are: 1) What are PSTs’ emotions towards insects and what elements mediate these? 2) To what extent are insects interesting for PSTs and what criteria do they use when justifying this interest? 3) Is there a statistically significant association between PSTs’ emotions towards insects and their interest in them? To answer these questions, a content analysis was conducted on individual written responses to an open-ended questionnaire along with statistical analysis. Negative emotions are prevalent among pre-service teachers regarding most insect species, and morphology is the factor most strongly correlated with these negative emotions. A significant association was found between the participants’ interest in insects and the emotions they displayed, demonstrating that the participants’ lack of interest is influenced by their negative emotions. The implications point to the need to design training programmes oriented to help teachers overcome negative emotions and develop an interest in invertebrates.

Evaluating Chlorophyll and Nitrogen Production in Edible Plant Sources Grown Under 5 Gigahertz Radiofrequency Radiation Emissions

By 2022 the demand for constant connectivity to high speed wireless communication networks is predicted to skyrocket with over 12 billion mobile devices and almost half a billion public Wi‐Fi hot spots. Both 5th generation (5G) cellular networks and current IEEE 802.11 Wi‐Fi can transmit radiofrequencies in the 5 Giga Hertz (5 GHz) range. Higher frequencies, such as those in the 5 GHz range, have been shown to be more harmful to humans and biological systems than lower frequencies. Although not well understood, frequencies generated in this range by newly established 5G cellular networks, and common Wi‐Fi 5 GHz networks, may pose a danger to biological systems which could have a significant impact on human health.This work looks to examine the effects of 5 GHz radiofrequency radiation on chlorophyll production and nitrogen levels in green leafy plants, in particular spinach. Chlorophyll is the most important intermediate in the conversion of light to organic matter in photosynthesis. Nitrogen is known to be directly proportional to chlorophyll content and is found in high amounts within enzymes, proteins, and thylakoid membranes required for photosynthesis. Spinach is known to have high levels of chlorophyll and has been chosen as the plant for testing. Using a TYS‐B Portable Chlorophyll Meter, chlorophyll and nitrogen levels will be non‐destructively measured over 5 weeks of growth under close bombardment from 5 GHz generated radio emissions in treatment groups and control groups shielded from all radio frequency emissions.If statistical significance suggests chlorophyll and nitrogen levels are decreased between treatment and control groups, further investigation may be warranted to assess the impact on human and plant health. Lower chlorophyll levels could decrease overall group weight and may contribute to a decline in pollinators. Decreased pollinators and lower crop yields could cost consumers billions of dollars in lower availability. As high frequency radio emissions continue to increase across the globe, any information would be available in determining possible dangers from these new technologies.Support or Funding Information• Bridges to Baccalaureate Grant awarded through National Institute of General Medical Sciences, Coconino Community College NIH Grant # 1R25GM102788‐01

Land cover composition, local plant community composition and honeybee colony density affect wild bee species assemblages in a Mediterranean biodiversity hot-spot

Identifying environmental drivers which structure wild bee species assemblages appears essential in a context of worldwide pollinator decline. During a two-year survey, we studied wild bee species assemblages in an 85km2 protected area dominated by Mediterranean scrubland, the Calanques National Park, located in southern France. Our objectives were (i) to assess the composition of the wild bee species assemblages, and (ii) to explore the effect of a) land cover composition (anthropogenic zone, low scrubland, forest and rocky land cover), b) local plant community composition, and c) honeybee colony density on wild bee species assemblages. On 17 circular 100m2 plots, we collected 541 specimens belonging to 87 wild bee species. We found that large bee species were significantly influenced by land cover composition within a 1000m radius. More specifically, we observed that the presence of a diversified land cover composition within a 1000m radius maximized large wild bee species richness, whereas large bee abundance and richness were negatively affected by honeybee colony density. Small wild bee species were structured by the local plant community composition within 100m2 plots and by land cover composition within a 1000m radius. Their occurrence were related to the local composition of plants growing on deep soils in scrublands. The Calanques National Park, which is the only European park located at the interface with a large city and consequently suffers from anthropic pressure, encompasses several types of land cover which are beneficial for a wide diversity of bees. However, we would like to raise awareness among park managers regarding beekeeping activities within this territory which includes diverse types of land cover favorable for wild bee species.

Characterizing honey bee exposure and effects from pesticides for chemical prioritization and life cycle assessment

Agricultural pesticides are key contributors to pollinator decline worldwide. However, methods for quantifying impacts associated with pollinator exposure to pesticides are currently missing in comparative risk screening, chemical substitution and prioritization, and life cycle impact assessment methods. To address this gap, we developed a method for quantifying pesticide field exposure and ecotoxicity effects of honey bees as most economically important pollinator species worldwide. We defined bee intake and dermal contact fractions representing respectively oral and dermal exposure per unit mass applied, and tested our model on two pesticides applied to oilseed rape. Our results show that exposure varies between types of forager bees, with highest dermal contact fraction of 59 ppm in nectar foragers for lambda-cyhalothrin (insecticide), and highest oral intake fractions of 32 and 190 ppm in nectar foragers for boscalid (fungicide) and lambda-cyhalothrin, respectively. Hive oral exposure is up to 115 times higher than forager oral exposure. Combining exposure with effect estimates yields impacts, which are three orders of magnitude higher for the insecticide. Overall, nectar foragers are the most affected forager type for both pesticides, dominated by oral exposure. Our framework constitutes an important step toward integrating pollinator impacts in chemical substitution and life cycle impact assessment, and should be expanded to cover all relevant pesticide-crop combinations.

African sunbirds predominantly pollinate plants useful to humans

Abstract Birds provide multiple ecological services that benefit humans including pollination. In Africa, sunbirds are the dominant vertebrate pollinator. Here we present a species-level assessment for African sunbirds of the number and relative frequency of their food plants that have useful properties to humans. We conducted this analysis by compiling and integrating known sunbird food plants with useful tropical plant and tropical cultivated plant databases. Across Africa, 68% of the 329 genera and 44% of the 468 species of sunbirds’ known food plants are used by humans for medicine, food, building materials, or other uses. Yet most genera and species of useful plants are visited by a small number of sunbird species. The median number of sunbird species that visit a useful genus and species of plant is two and one, respectively. Of the 409 genera and 308 species of useful plants that are sunbird pollinated across one or more of the six predominant habitats for sunbirds, 67% of genera and 71% of species are pollinated by sunbird species that are forest or woodland dependent. Additionally, 58% of all genera and 83% of all species of useful plants pollinated by sunbirds are non-cultivated. In Africa, non-cultivated sunbird-pollinated useful plants are almost entirely collected, used, and traded locally rather than regionally or internationally. Our results indicate that African sunbirds provide important ecological services as pollinators that benefit humans, and these services are provided largely at a local scale. Given the decline of invertebrate and vertebrate pollinators both globally and in Africa, sunbirds are important to the long-term conservation of many useful plants in Africa and hence human well-being.

A botanic garden as a tool to combine public perception of nature and life-science investigations on native/exotic plants interactions with local pollinators.

Life-sciences are pointing towards an alarming worldwide pollinator decline. This decline proceeds along with overall biodiversity losses, even in the context of urban landscapes and human welfare. At the same time, social-sciences are arguing an increased distance from nature, experienced by citizens. The strong connection between the public good and pollinator sustainability, even in urban areas, is well-documented. However, usually basic and applied life-sciences tend to underestimate public perception of nature, which is better tackled by the fields of social-sciences. Therefore, more efforts are needed to link scientific questions and public ‘perception’ of nature. We designed a transversal project where research questions directly confront public concerns: i.e., even while addressing scientific knowledge gaps, our questions directly arise from public concerns. Social studies highlighted that appreciation of (exotic) plants is related to the impact they may have on the surrounding natural environment: therefore, we investigated links of native and exotic flowers to local pollinators. Other studies highlighted that scientific results need to link to everyday individual experience: therefore, we investigated pollination modes of the renown Salvia, native and exotic, largely used in cuisine and gardening. The botanic garden was the promoter of scientific questions addressed by the public, and also collated the results in a travelling exhibition. The exhibition, together with a dedicated catalogue, were especially designed to enlighten the wide public on the relationships that plants, native and exotic alike, establish with the surrounding world.

Lethal and sublethal effects of toxicants on bumble bee populations: a modelling approach

Pollinator decline worldwide is well-documented; globally, chemical pesticides (especially the class of pesticides known as neonicotinoids) have been implicated in hymenopteran decline, but the mechanics and drivers of population trends and dynamics of wild bees is poorly understood. Declines and shifts in community composition of bumble bees (Bombus spp.) have been documented in North America and Europe, with a suite of lethal and sub-lethal effects of pesticides on bumble bee populations documented. We employ a mathematical model parameterized with values taken from the literature that uses differential equations to track bumble bee populations through time in order to attain a better understanding of toxicant effects on a developing colony of bumble bees. We use a delay differential equation (DDE) model, which requires fewer parameter estimations than agent-based models while affording us the ability to explicitly describe the effect of larval incubation and colony history on population outcomes. We explore how both lethal and sublethal effects such as reduced foraging ability may combine to affect population outcomes, and discuss the implications for the protection and conservation of ecosystem services.

Impact of Information Type and Source on Pollinator-friendly Plant Purchasing

The number of pollinators has been reported to be decreasing for the past several decades. Numerous sources (e.g., climate change, pesticides, loss of habitat) have been noted as potential contributing factors to the decline. With respect to the green industry, the impact of pesticides on pollinator decline and consumer response to this impact is of critical importance. Although no definitive link exists of pesticides being a major contributing factor to pollinator decline, some retailers have banned their suppliers from using certain pesticides. As various sources (e.g., universities, media, activist groups) provide information (both positive, neutral, and negative) about the impact of pesticides on pollinators, no information exists regarding how consumers value such information. Using a sample of Connecticut consumers, this study evaluates how both information source and information type impact a consumer’s decision to purchase pollinator-friendly plants in the future. The study finds that consumers exposed to either neutral (no link between pesticides and pollinator decline) or negative (link between pesticides and pollinator decline) information from universities and major media outlets indicate they will purchase more pollinator-friendly plants compared with the no information (control) treatment. The results show that information from the federal government, nursery/greenhouse industry associations, and environmental activist groups have the same impact on self-reported future pollinator-friendly plant purchasing as the no information group.

Worldwide Occurrence Records Reflect a Global Decline in Bee Species Richness

Wild and managed bees are key pollinators, providing ecosystem services to a large fraction of the world’s flowering plants, including ~85% of all cultivated crops. Recent reports of wild bee decline and its potential consequences are thus worrisome. However, evidence is mostly based on local or regional studies; global status of bee decline has not been assessed yet. To fill this gap, we analyzed publicly available worldwide occurrence records from the Global Biodiversity Information Facility spanning more than a century of specimen collection. We found that after the 1990’s the number of collected bee species declines steeply, and approximately 25% fewer species were reported between 2006 and 2015 relative to the number of species counted before the 1990’s. These trends are alarming and encourage swift action to avoid further decline of these key pollinators.

The Contribution of Managed Honey Bees to Crop Pollination, Food Security, and Economic Stability: Case of Ethiopia

This paper reviews the role and economic importance of the pollination service by honey bees (Apis mellifera) to agricultural crops and food security in the Ethiopian context. Honey bees provide pollination services that are crucial for sexual reproduction and improving the quality and quantity of many agricultural crops. From the significant 53 crops cultivated in Ethiopia, 33 (62.2%) of them are dependent on biological pollinators. Besides this, honey bees play a vital economic role, and their contribution to pollination service in agriculture crops is around 0.815 billion dollars in Ethiopia. Nevertheless, this contribution is unnoticed by Ethiopian farmers. Pollination by honey bee plays an essential role in human nutrition and supplies food security, income in households, and ecosystem services. Declines in insect pollinators, including honey bees across the world, have raised concerns about the supply of pollination services to agriculture, and it is because one-third of agriculture productions depend upon pollination, mainly by honey bees. Among the several factors responsible for the decline of honey bee colonies, improper pesticide application, and climate change are the elements and make them at risk. The potential adverse effects of pollinator declines include direct economic losses incurred by reduced crop yields as well as broader impacts on the agricultural activity because of lower productivity in the ecosystems. Through promoting and the use of honey bee pollination service as agricultural development packages, it is possible to improve honey bee production and crop yield in Ethiopia.

Population Growth and Insecticide Residues of Honey Bees in Tropical Agricultural Landscapes

Global decline of pollinators, especially bees, has been documented in many countries. Several causes such as land-use change and agricultural intensification are reported to be the main drivers of the decline. The objective of this study was to investigate the effect of land use on honey bee and stingless bee populations. Research was conducted in Bogor and Malang to compare between two different geographical areas. Managed bees such as honey bees (Apis cerana and A. mellifera) and stingless bees (Tetragonula laeviceps) were investigated to examine the effect of agricultural intensification. Field experiments were conducted by placing beehives in selected habitats (i.e., beekeeper gardens, forests areas, and agriculture areas). Population growth and neonicotinoid residue analysis of bees in different hive locations were measured to study the effect of habitat type. Population growth of bees represents the forager abundance and colony weight. Based on the analysis, we found that habitat type affected forager abundance and colony weight of honey bees (p < 0.05), although the patterns were different between species, region, as well as season. Forests could support the stingless bee colony better than agriculture and home garden habitats. Insecticide (neonicotinoid) was barely recorded in both honey bees and stingless bees.

Evaluating Effects of a Critical Micronutrient (24-Methylenecholesterol) on Honey Bee Physiology.

Although poor nutrition is cited as one of the crucial factors in global pollinator decline, the requirements and role of several important nutrients (especially micronutrients) in honey bees are not well understood. Micronutrients, viz. phytosterols, play a physiologically vital role in insects as precursors of important molting hormones and building blocks of cellular membranes. There is a gap in comprehensive understanding of the impacts of dietary sterols on honey bee physiology. In the present study, we investigated the role of 24-methylenecholesterol—a key phytosterol—in honey bee nutritional physiology. Artificial diets with varying concentrations of 24-methylenecholesterol (0%, 0.1%. 0.25%, 0.5%, 0.75%, and 1% dry diet weight) were formulated and fed to honey bees in a laboratory cage experiment. Survival, diet consumption, head protein content, and abdominal lipid contents were significantly higher in dietary sterol-supplemented bees. Our findings provide additional insights regarding the role of this important sterol in honey bee nutritional physiology. The insights gleaned from this study could also advance the understanding of sterol metabolism and regulation in other bee species that are dependent on pollen for sterols, and assist in formulation of a more complete artificial diet for honey bees (Apis mellifera Linnaeus, 1758) (Hymenoptera: Apidae).

Vegetation monitoring in a 100-year-old calcareous grassland reserve in Germany

Calcareous grasslands harbor specialized species and are cultural relics. Therefore, they are prime habitates for conservation and restoration, but negative effects of inappropriate management, eutrophication and fragmentation continue to exist. These effects also influence grasslands which serve as target for restoration. Unfortunately, monitoring of long-term vegetation dynamics in calcareous grassland is rare. Here, we studied such changes over 35 years in the nature reserve ‘Garchinger Heide’, which is well known for its high abundance of rare species. Furthermore, it has been managed for conservation for more than 100 years. Therefore, species composition, total species richness, numbers of habitat specialists, red-list species and the proportion of graminoids were examined in 42 plots with frequency recording (1984–2018), and in 40 plots based on vegetation relevés (2003–2018). Ellenberg indicator values, specific leaf area, seed mass, and canopy height were analysed to detect patterns in trait response to environmental change. Within 35 years there were considerable vegetation dynamics. Specialist plants of calcareous grassland and red list species decreased, and insect-pollinated species declined in contrast to wind-pollinated species. Ellenberg N as well as graminoid abundance, canopy height, seed mass, and multi-trait functional dispersion increased, while specific leaf area showed no such change. Our results suggest that environmental change like deposition of atmospheric nitrogen, management regime, pollinator decline or isolation could be correlated with vegetation dynamics, while these correlations would need experimental confirmation. The grassland management certainly helped achieving several conservation goals, although it was not able to stop a decrease of rare species. The results show that also in nature reserves with long-term conservation management monitoring is essential to detect vegetation dynamics and to adjust the management to these changes.

Native habitat mitigates feast–famine conditions faced by honey bees in an agricultural landscape

Intensive agriculture can contribute to pollinator decline, exemplified by alarmingly high annual losses of honey bee colonies in regions dominated by annual crops (e.g., midwestern United States). As more natural or seminatural landscapes are transformed into monocultures, there is growing concern over current and future impacts on pollinators. To forecast how landscape simplification can affect bees, we conducted a replicated, longitudinal assessment of honey bee colony growth and nutritional health in an intensively farmed region where much of the landscape is devoted to production of corn and soybeans. Surprisingly, colonies adjacent to soybean fields surrounded by more cultivated land grew more during midseason than those in areas of lower cultivation. Regardless of the landscape surrounding the colonies, all experienced a precipitous decline in colony weight beginning in August and ended the season with reduced fat stores in individual bees, both predictors of colony overwintering failure. Patterns of forage availability and colony nutritional state suggest that late-season declines were caused by food scarcity during a period of extremely limited forage. To test if habitat enhancements could ameliorate this response, we performed a separate experiment in which colonies provided access to native perennials (i.e., prairie) were rescued from both weight loss and reduced fat stores, suggesting the rapid decline observed in these agricultural landscapes is not inevitable. Overall, these results show that intensively farmed areas can provide a short-term feast that cannot sustain the long-term nutritional health of colonies; reintegration of biodiversity into such landscapes may provide relief from nutritional stress.

Pollinator restoration in Brazilian ecosystems relies on a small but phylogenetically-diverse set of plant families

The alarming rate of global pollinator decline has made habitat restoration for pollinators a conservation priority. At the same time, empirical and theoretical studies on plant-pollinator networks have demonstrated that plant species are not equally important for pollinator community persistence and restoration. However, the scarcity of comprehensive datasets on plant-pollinator networks in tropical ecosystems constrains their practical value for pollinator restoration. As closely-related species often share traits that determine ecological interactions, phylogenetic relationships could inform restoration programs in data-scarce regions. Here, we use quantitative bee-plant networks from Brazilian ecosystems to test if priority plant species for different restoration criteria (bee species richness and visitation rates) can be identified using interaction networks; if phylogenetic relationships alone can guide plant species selection; and how restoration criteria influence restored network properties and function. We found plant species that maximised the benefits of habitat restoration for bees (i.e., generalists and those with distinct flower-visitor species) were clustered in a small number of phylogenetically-diverse plant families, and that prioritising the recovery of bee visitation rates improved both stability and function of restored plant-pollinator networks. Our approach can help guide restoration of pollinator communities, even where information on local ecosystems is limited.