Search

Funder: Consejo Nacional de Ciencia y Tecnolog?a, Funder: Rural and Environment Science and Analytical Services Division, Funder: Montana Department of Agriculture, While wild pollinators play a key role in global food production, their assessment is currently missing from the most commonly used environmental impact assessment method, Life Cycle Assessment (LCA). This is mainly due to constraints in data availability and compatibility with LCA inventories. To target this gap, relative pollinator abundance estimates were obtained with the use of a Delphi assessment, during which 25 experts, covering 16 nationalities and 45 countries of expertise, provided scores for low, typical, and high expected abundance associated with 24 land use categories. Based on these estimates, this study presents a set of globally generic characterization factors (CFs) that allows translating land use into relative impacts to wild pollinator abundance. The associated uncertainty of the CFs is presented along with an illustrative case to demonstrate the applicability in LCA studies. The CFs based on estimates that reached consensus during the Delphi assessment are recommended as readily applicable and allow key differences among land use types to be distinguished. The resulting CFs are proposed as the first step for incorporating pollinator impacts in LCA studies, exemplifying the use of expert elicitation methods as a useful tool to fill data gaps that constrain the characterization of key environmental impacts.

Aim: Aggregated species occurrence data are increasingly accessible through public databases for the analysis of temporal trends in species’ distributions. However, biases in these data present challenges for robust statistical inference. We assessed potential biases in data available through GBIF on the occurrences of four flower-visiting taxa: bees (Anthophila), hoverflies (Syrphidae), leaf-nosed bats (Phyllostomidae), and hummingbirds (Trochilidae). We also assessed whether and to what extent data mobilisation efforts improved our ability to estimate trends in species’ distributions. Location: The Neotropics. Methods: We used five data-driven heuristics to screen the data for potential geographic, temporal and taxonomic biases. We began with a continental-scale assessment of the data for all four taxa. We then identified two recent data mobilisation efforts (2021) that drastically increased the quantity of records of bees collected in Chile available through GBIF. We compared the dataset before and after the addition of these new records in terms of their biases and their impact on estimated trends in species’ distributions. Results: We found evidence of potential sampling biases for all taxa. The addition of newly-mobilised records of bees in Chile decreased some biases but introduced others. Despite increasing the quantity of data for bees in Chile sixfold, estimates of temporal trends in species’ distributions derived using the post-mobilisation dataset were broadly similar to what would have been estimated before their introduction. Main conclusions: Our results highlight the challenges associated with drawing statistically robust inferences about trends in species’ distributions using publicly available data. Mobilising historic records will not always enable trend estimation because more data does not necessarily equal less bias. Analysts should carefully assess their data before conducting analyses: this might enable the estimation of more robust trends and help to identify strategies for effective data mobilisation. Our study also reinforces the need for well-designed, standardized monitoring of pollinators worldwide.

Yields are in decline for a number of crops and regions, but the drivers of this process are poorly known. Global decreases in pollinator abundance and diversity have been proposed as a major driver of yield declines in crops that depend on animals, mostly bees, to produce fruits and seeds. Alternatively, widespread tree mortality has been directly and indirectly related to global climate change, which could also explain yield decreases in tree crops. As tree crops are expected to be more dependent on pollinators than other crop types, disentangling the relative influence of growth form and pollinator dependence is relevant to identify the ultimate factors driving yield declines. The incidence of yield decline, estimated as a negative average yield growth rate from 1961 to 2020, was measured in 4270 time series, involving 136 crops and 163 countries and territories. About one-fourth of all time series showed negative average rates of yield growth, a characteristic associated with both high pollinator dependence and a tree growth form. Because pollinator dependence and plant growth form were partially correlated, we disentangled the effect of each of these two predictors using a series of generalized linear mixed models that evaluated direct and indirect associations. Our analyses revealed a stronger association of yield decline with growth form than with pollinator dependence, a relationship that persisted after partialling out the effect of pollinator dependence. In particular, yield declines were more common among tree than herbaceous and shrub crops in all major regions but in Africa, a continent showing a high incidence of yield declines irrespective of growth form. These results suggest that global climate change rather than pollinator decline could already be impacting tree crop productivity.

Ecosystems are interconnected and complex, but conservation has often focused on rehabilitating individual species. A systems-ecology approach aims to support overall structure and maintain functions of the whole ecosystem, and may be especially pertinent for mutualistic plant-pollinator communities. This approach focuses on species interactions as the units to be conserved within the larger ecosystem. Analyzing species interactions is a more holistic approach because it incorporates a broader web of organisms, and considers the plethora of potential indirect influences from interacting partners. In this article, we suggest pollinator researchers focus on plant-pollinator networks to inform conservation programs and best support the coexistence of pollinators and plants within natural and agricultural systems. We propose that a system-ecology perspective is the most promising way to simultaneously improve pollinator conservation, agricultural sustainability, and human well-being.

Plant recruitment interactions (i.e., what recruits under what) shape the composition, diversity, and structure of plant communities. Despite the huge body of knowledge on the mechanisms underlying recruitment interactions among species, we still know little about the structure of the recruitment networks emerging in ecological communities. Modeling and analyzing the community-level structure of plant recruitment interactions as a complex network can provide relevant information on ecological and evolutionary processes acting both at the species and ecosystem levels. We report a data set containing 143 plant recruitment networks in 23 countries across five continents, including temperate and tropical ecosystems. Each network identifies the species under which another species recruits. All networks report the number of recruits (i.e., individuals) per species. The data set includes >850,000 recruiting individuals involved in 118,411 paired interactions among 3318 vascular plant species across the globe. The cover of canopy species and open ground is also provided. Three sampling protocols were used: (1) The Recruitment Network (RN) protocol (106 networks) focuses on interactions among established plants (“canopy species”) and plants in their early stages of recruitment (“recruit species”). A series of plots was delimited within a locality, and all the individuals recruiting and their canopy species were identified; (2) The paired Canopy-Open (pCO) protocol (26 networks) consists in locating a potential canopy plant and identifying recruiting individuals under the canopy and in a nearby open space of the same area; (3) The Georeferenced plot (GP) protocol (11 networks) consists in using information from georeferenced individual plants in large plots to infer canopy-recruit interactions. Some networks incorporate data for both herbs and woody species, whereas others focus exclusively on woody species. The location of each study site, geographical coordinates, country, locality, responsible author, sampling dates, sampling method, and life habits of both canopy and recruit species are provided. This database will allow researchers to test ecological, biogeographical, and evolutionary hypotheses related to plant recruitment interactions. There are no copyright restrictions on the data set; please cite this data paper when using these data in publications., Fondo Europeo de Desarrollo Regional, Grant/Award Number, ICTS-2017-08-CSIC-4; SUMHAL, Grant/Award Numbers: 418RT0555, 501100011033, LIFEWATCH-2019-09-CSIC-13, MCIN/ AEI/10.13039, PGC2018-100966-B-100, PID2020-113157GB-I00, POPE 2014-2020

Insect pollinators have been relocated by humans for millennia and are, thus, among the world’s earliest intentional exotic introductions. The introduction of managed bees for crop pollination services remains, to this day, a common and growing practice worldwide and the number of different bee species that are used commercially is increasing. Being generalists and frequently social, these exotic species have the potential to have a wide range of impacts on native bees and plants. Thus, understanding the consequences of introduced species on native pollinator systems is a priority. We generated a global database and evaluated the impacts of the two main groups of invasive bees, Apis mellifera and Bombus spp., on their pollination services to native flora and impacts on native pollinators. In a meta-analysis, we found that per-visit pollination efficiency of exotic pollinators was, on average, 55% less efficient than native pollinators when visiting flowers of native species. In contrast to per-visit pollination efficiency, our meta-analysis showed that visitation frequency by exotic pollinators was, on average, 80% higher than native pollinators. The higher visitation frequency of exotic pollinators overcame deficiencies in pollen removal and transfer resulting in seed/fruit set levels similar to native pollinators. Also, evidence showed that exotic pollinators can displace native insect and bird pollinators. However, the direct effects of exotic insect pollinators on native pollination systems can be context dependent, ranging from mutualism to antagonism.

Fil: Garibaldi, Lucas A. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Garibaldi, Lucas A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Aizen, Marcelo A. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente. Río Negro, Argentina. Fil: Sáez, Agustín. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medio Ambiente Argentina. Río Negro, Argentina. Fil: Gleiser, Gabriela. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medio Ambiente Argentina. Río Negro, Argentina. Fil: Strelin, Marina M. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medio Ambiente Argentina. Río Negro, Argentina. Domestication generally involves two sequential processes: initial identification of wild species with desirable characteristics (‘progenitor filtering’) and subsequent artificial and natural selection that, respectively, improve features preferred by humans and adapt species to cultivation/captivity (‘domestication selection’). Consequently, domesticated species can differ from wild species and may share characteristics owing to convergent evolution (‘domestication syndrome’). Baring evolutionary constraints, domestication selection may generate extreme phenotypes that transcend the ‘boundaries of nature’ evident for wild species. Despite evidence of domestication syndromes in some clades, broader contributions of progenitor filtering and domestication selection to characteristics of contemporary domesticated species have received limited attention. Using comparative analysis of 49 grain-crop and 87 wild annual plant species from 15 families, we (1) addressed whether plants of crop and wild species differ for mean seed number, per-seed mass and total seed-mass investment; (2) assessed contributions of (a) progenitor filtering and (b) domestication selection to these differences; (3) evaluated whether crop characteristics exceed the boundaries of nature and (4) assessed whether seed-production characteristics of grain crops constitute components of a generic domestication syndrome. On average, grain-crop plants produce heavier seeds and greater total seed mass than wild species, but seed number per plant does not differ. Comparison of wild species between genera with or without crop species found no evidence of progenitor filtering. In contrast, crop species differed from congeneric wild species for the mass traits, but not for seed number. Greater seed investment by crops is consistent with artificial selection for enhanced seed yield (mass per harvested area), whereas heavier individual seeds suggest selection for improved nutritional quality and (or) adaptation to cultivation environments. Seed number–size characteristics of grain-crop species lie within the bivariate variation among wild species and so do not exceed the boundaries of nature. Seed number and size varied similarly between species types and generally aligned with seed-investment isoclines, suggesting an upper investment limit. Despite greater average investment in seed production and individual seeds by grain-crop species, seed-production characteristics did not vary less among crop species than among wild species, which is inconsistent with a common domestication syndrome. Domestication generally involves two sequential processes: initial identification of wild species with desirable characteristics (‘progenitor filtering’) and subsequent artificial and natural selection that, respectively, improve features preferred by humans and adapt species to cultivation/captivity (‘domestication selection’). Consequently, domesticated species can differ from wild species and may share characteristics owing to convergent evolution (‘domestication syndrome’). Baring evolutionary constraints, domestication selection may generate extreme phenotypes that transcend the ‘boundaries of nature’ evident for wild species. Despite evidence of domestication syndromes in some clades, broader contributions of progenitor filtering and domestication selection to characteristics of contemporary domesticated species have received limited attention. Using comparative analysis of 49 grain-crop and 87 wild annual plant species from 15 families, we (1) addressed whether plants of crop and wild species differ for mean seed number, per-seed mass and total seed-mass investment; (2) assessed contributions of (a) progenitor filtering and (b) domestication selection to these differences; (3) evaluated whether crop characteristics exceed the boundaries of nature and (4) assessed whether seed-production characteristics of grain crops constitute components of a generic domestication syndrome. On average, grain-crop plants produce heavier seeds and greater total seed mass than wild species, but seed number per plant does not differ. Comparison of wild species between genera with or without crop species found no evidence of progenitor filtering. In contrast, crop species differed from congeneric wild species for the mass traits, but not for seed number. Greater seed investment by crops is consistent with artificial selection for enhanced seed yield (mass per harvested area), whereas heavier individual seeds suggest selection for improved nutritional quality and (or) adaptation to cultivation environments. Seed number–size characteristics of grain-crop species lie within the bivariate variation among wild species and so do not exceed the boundaries of nature. Seed number and size varied similarly between species types and generally aligned with seed-investment isoclines, suggesting an upper investment limit. Despite greater average investment in seed production and individual seeds by grain-crop species, seed-production characteristics did not vary less among crop species than among wild species, which is inconsistent with a common domestication syndrome.

Greater susceptibility to herbivory can arise as an effect of crop domestication. One proposed explanation is that defenses decreased intentionally or unintentionally during the domestication process, but evidence for this remains elusive. An alternative but nonexclusive explanation is presumed selection for higher nutritional quality. We used a metaanalytical approach to examine susceptibility to herbivores in fruit and seed crops and their wild relatives. Our analyses provide novel insights into the mechanisms of increased susceptibility by evaluating whether it can be attributed to either a reduction in herbivore defensive traits, including direct/indirect and constitutive/inducible defenses, or an increase in the nutritional content of crops. The results confirm higher herbivory and lower levels of all types of defenses in crops compared to wild relatives, although indirect defenses were more affected than direct ones. Contrary to expectations, nutritional quality was lower in crops than in wild relatives, which may enhance biomass loss to herbivores if they increase consumption to meet nutritional requirements. Our findings represent an important advance in our understanding of how changes in defensive and nutritional traits following domestication could influence, in combination or individually, crop susceptibility to herbivore attacks.

Fil: Aizen, Marcelo A. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente. Rio Negro, Argentina. Fil: Garibaldi, Lucas A. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Garibaldi, Lucas A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Harder, Lawrence D. University of Calgary. Department of Biological Sciences. Canada. Mounting evidence shows that pollinators are declining as a result of widespread environmental degradation. This loss raises concerns that a global pollination crisis could threaten the human food supply by decreasing crop yield and even promote famine under a hypothetical scenario of total pollinator extinction. This catastrophic possibility has prompted intense interest from scientists, politicians and the general public. However, three lines of evidence do not support such an apocalyptic scenario. First, even though the abundance and diversity of wild pollinators are declining worldwide, the global population of managed honey-bee hives has increased by ~80% since the early 1960s. Second, agricultural production would decrease by

Invasive species can reach high abundances and dominate native environments. One of the most impressive examples of ecological invasions is the spread of the African subspecies of the honey bee throughout the Americas, starting from its introduction in a single locality in Brazil. The invasive honey bee is expected to more negatively impact bee community abundance and diversity than native dominant species, but this has not been tested previously. We developed a comprehensive and systematic bee sampling scheme, using a protocol deploying 11,520 pan traps across regions and crops for three years in Brazil. We found that invasive honey bees are now the single most dominant bee species. Such dominance has not only negative consequences for abundance and species richness of native bees but also for overall bee abundance (i.e., strong “numerical” effects of honey bees). Contrary to expectations, honey bees did not have stronger negative impacts than other native bees achieving similar levels of dominance (i.e., lack of negative “identity” effects of honey bees). These effects were markedly consistent across crop species, seasons and years, and were independent from land-use effects. Dominance could be a proxy of bee community degradation and more generally of the severity of ecological invasions.

Fil: Dicks, Lynn V. University of Cambridge. Department of Zoology. Reino Unido. Fil: Breeze, Tom D. Reading University. School of Agriculture, Policy and Development. Centre for Agri-Environmental Research. Reino Unido. Fil: Ngo, Hien T. IPBES Secretariat. Alemania. Fil: Senapathi, Deepa. Reading University. School of Agriculture, Policy and Development. Centre for Agri-Environmental Research. Reino Unido. Fil: An, Jiandong. Chinese Academy of Agricultural Sciences. Institute of Apicultural Research. China. Fil: Aizen, Marcelo A. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente. Río Negro, Argentina. Fil: Basu, Parthiba. University of Calcutta. Department of Zoology. India. Fil: Buchori, Damayanti. IPB University. Center for Transdisciplinary and Sustainability Sciences. Indonesia. Fil: Galetto, Leonardo. Universidad de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Córdoba, Argentina. Fil: Garibaldi, Lucas A. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Garibaldi, Lucas A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Gemmill-Herren, Barbara. World Agroforestry Centre. Kenia. Fil: Howlett, Brad G. The New Zealand Institute for Plant & Food Research Limited. Nueva Zelanda. Fil: Imperatriz-Fonseca, Vera L. University of Sao Paulo. Biosciences Institute. Brasil Fil: Johnson, Steven D. University of KwaZulu-Natal. School of Life Sciences. Centre for Functional Biodiversity. Sudáfrica. Fil: Kovács-Hostyánszki, Anikó. Centre for Ecological Research. Institute of Ecology and Botany. Hungría. Fil: Jung Kwon, Yong. Kyungpook National University. School of Applied Biosciences. Corea del Sur. Fil: Lattorff, H. Michael G. International Centre of Insect Physiology and Ecology. Kenia. Fil: Lungharwo, Thingreipi. Naga Women’s Union. India. Fil: Seymour, Colleen L. Kirstenbosch Research Centre. South African National Biodiversity Institute. Sudáfrica. Fil: Vanbergen, Adam J. University of Bourgogne Franche-Comté. Francia. Fil: Potts, Simon G. Reading University. School of Agriculture, Policy and Development.Centre for Agri-Environmental Research. Reino Unido. Pollinator decline has attracted global attention and substantial efforts are underway to respond through national pollinator strategies and action plans. These policy responses require clarity on what is driving pollinator decline and what risks it generates for society in different parts of the world. Using a formal expert elicitation process, we evaluated the relative regional and global importance of eight drivers of pollinator decline and ten consequent risks to human well-being. Our results indicate that global policy responses should focus on reducing pressure from changes in land cover and configuration, land management and pesticides, as these were considered very important drivers in most regions. We quantify how the importance of drivers and risks from pollinator decline, differ among regions. For example, losing access to managed pollinators was considered a serious risk only for people in North America, whereas yield instability in pollinator-dependent crops was classed as a serious or high risk in four regions but only a moderate risk in Europe and North America. Overall, perceived risks were substantially higher in the Global South. Despite extensive research on pollinator decline, our analysis reveals considerable scientific uncertainty about what this means for human society.

Fil: Hünicken, Pablo L. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Hünicken, Pablo L.. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Morales, Carolina L. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente. Río Negro, Argentina. Fil: Aizen, Marcelo A. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medio Ambiente Argentina. Río Negro, Argentina. Fil: Andersson, Georg K. S. Lund University. Suecia. Fil: García, Nancy. Agencia de Desarrollo Económico del Neuquén. Centro PYME. Neuquén, Argentina. Fil: Garibaldi, Lucas A. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Garibaldi, Lucas A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. One of the most important challenges facing global agriculture is to ensure an adequate, stable food supply while conserving soil, water and biodiversity. The yield stability of pollinator-dependent crops, such as pear and apple, can be negatively affected by variability of the pollination service, which in turn can reduce mean yield. We explored how mean crop yield and yield variability were affected by pollinators and variability in their provision of the pollination service. Over four seasons we conducted a manipulative experiment in six pear and eight apple farms; fruit set (i.e., no. fruits/ no. flowers) was compared between flowers exposed to pollinators and those excluded from pollinators. We also recorded pollinator visitation rate to exposed flowers. We estimated the mean levels and spatial and temporal variability of both pollinator visitation and yield response by calculating the mean values per farm and the spatial (i.e., across trees within farm) and temporal (i.e., across seasons within farm) coefficients of variation (CV) for visitation rate and fruit set. Despite homogeneous irrigation and fertilization, we found strong variability in fruit set in both crops (pear spatial and temporal CV: 0.57 and 0.4, respectively; apple: 0.62 and 0.52). Pollinator exclusion reduced mean fruit set considerably in both crops (pears: a reduction of 50%, apples: 71–92%), and increased spatial and temporal variability (pears: 296% and 197% for spatial and temporal variability, respectively; apples: 385% and 329%). Visitation rates in pears were positively associated with mean fruit set and negatively related to its spatial CV. Also, in this crop we found a positive relation between the spatial CV of visitation rate and fruit set. However, there was no evidence that visitation rate in open-pollinated apple flowers affected either mean fruit set or its spatial or temporal variability. Apple trees received one order of magnitude more visits per flower than pear trees, suggesting that in this system the pollination service meets the pollination demand of the apple crop. Overall, our results highlight the importance of management practices that prioritize pollination service, thus ensuring a high, stable yield.

Mosses are a dominant ground cover in a wide array of ecosystems, especially in those developing under cold-stressed environments such as arctic and alpine ice-melting glacial forelands. Consequently, mosses may influence the performance and distribution of other plants. Here, we assessed the nature of interactions between vascular plants and cushion-forming mosses in three alpine communities in the northern Patagonian Andes. We recorded species richness, plant abundance and cover of vascular plants within and outside moss cushions, measuring also patch area and moss layer depth. To determine the effect of mosses on vascular plant assemblages, we calculated the relative interaction index (RII) in terms of richness, abundance and cover of all vascular plants, and of individual species. Moss-cushion patches showed higher species richness, plant abundance and cover in comparison with bare ground areas. Overall, the diversity of vascular plants increased with both moss-cushion area and layer depth. Species-specific RII values revealed that the effects of moss cushions on neighboring vascular plants were predominantly positive for all three plant communities surveyed. These results highlight the role of mosses as nurse plants in alpine ice-melting glacial forelands and, thus, as ecosystem engineers that can be key in maintaining vascular plant diversity.

The area cultivated with pollinator-dependent crops is increasing worldwide, while a shortfall in pollinator availability is a growing problem in many agroecosystems. For this reason, many highly pollinator-dependent crops are nowadays pollinated artificially by humans. Here, we compared the efficiency of artificial and bee pollination practices on the mean level and stability of pollination and fruit production of kiwifruit. In a kiwifruit orchard, we tagged a total of 800 flowers from 40 plants, half were pollinated by honeybees while the other half by spraying pollen on flowers, the most commonly pollination technique used in kiwifruit. During harvest, we measured fruit set, number of seeds per fruit, and fruit weight. On average, bee-pollinated plants produced 40% more fruits than artificially-pollinated plants. Also, fruits from bee-pollinated flowers contained, on average, 34% more seeds, showing also 2.8 times less variability in number of seeds per fruit than those pollinated artificially. Following the same trend, bee-pollinated flowers produce fruits that were 34% heavier and 1.5 times less variable in weight. These results showed that bee pollination resulted in higher fruit production, and heavier and more homogeneous fruits than artificial pollination. According to these results, we encourage growers and land managers to use pollination management practices based on honey bees, instead of the use of mechanical pollination systems. Fil: Sáez, Agustín. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche; Argentina Fil: Negri, Pedro. Universidad Nacional de Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Cs.exactas y Naturales. Instituto de Investigaciones En Sanidad Produccion y Ambiente. - Comision de Investigaciones Cientificas de la Provincia de Buenos Aires. Instituto de Investigaciones En Sanidad Produccion y Ambiente.; Argentina Fil: Viel, Matias. Universidad de San Andrés; Argentina Fil: Aizen, Marcelo Adrian. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche; Argentina

While feeding, foragers can alter their environment. Such alteration constitutes ecological niche construction (ENC) if it enables future benefits for the constructor and conspecific individuals. The environmental modification may also affect non-constructing, bystander species, especially if they share resources with constructor species. If so, ENC could confer the constructor species a competitive advantage by both enhancing its foraging returns and reducing those of bystander species. Expectations - (E1) ENC frequency should vary positively with the recent and current density of the constructor species, and (E2) constructors should use modifications disproportionately. In contrast, bystanders should (E3) experience intensified competition for the affected resource, and (E4) exhibit diverse, possibly mitigating, responses to ENC, depending on opportunity and relative benefits. We investigated these expectations in Argentina for competition for Fuchsia magellanica nectar between an invasive bumble bee Bombus terrestris (terr: putative constructor), which often bites holes at the bases of floral tubes to rob nectar, and native B. dahlbomii (dahl: bystander), which normally accesses Fuchsia nectar through the flower mouth (front visits). Robbing holes constitute ENC, as they persist until the 7-day flowers wilt. The dynamics of the incidence of robbed flowers, abundance of both bees and the number and types of their flower visits (front or robbing) were characterised by alternate-day surveys of plants during 2.5 months. After initially accessing Fuchsia nectar via front visits, terr switched to robbing and its abundance on Fuchsia increased 20-fold within 10 days (E2). Correspondingly, the incidence of robbed flowers varied positively with recent and past terr abundance (E1). In contrast, dahl abundance remained low and varied negatively with the incidence of robbed flowers (E3). When terr ceased visiting Fuchsia, dahl abundance increased sixfold within 10 days (E3), possibly because many dahl previously had avoided competition with terr by feeding on other plant species (E4). While terr was present, dahl on Fuchsia used front visits (tolerance) or used existing robbing holes (adoption: E4). The diverse dahl responses suggest partial compensation for competition with terr. ENC alters competitive asymmetry, favouring constructor species. However, bystander responses can partially offset this advantage, perhaps facilitating coexistence.Los animales pueden alterar su ambiente como consecuencia del forrajeo. Esta alteración constituye una forma de construcción de nicho ecológico (CNE) cuando la misma promueve beneficios para el constructor y otros individuos de la misma especie. Esta modificación ambiental puede también afectar otras especies no involucradas directamente en la CNE, especialmente cuando comparten recursos con la especie constructora. En este caso, la CNE puede conferir una ventaja competitiva a la especie constructora, incrementado sus beneficios alimenticios en detrimento de los de las especies no constructoras. Expectativas - (E1) La frecuencia de eventos de CNE debería variar positivamente con la densidad presente y pasada de la especie constructora, y (E2) los individuos de la especie constructora deberían usar las modificaciones asociadas a la CNE en forma diferencial. Por el contrario, los individuos de las otras especies que usen el mismo recurso deberían (E3) experimentar una intensificación de la competencia, y (E4) exhibir una diversidad de respuestas, algunas que atenúen las consecuencias negativas de la CNE, lo que va a depender de la oportunidad y de los beneficios relativos. En Argentina, investigamos el cumplimiento de estas expectativas en la competencia por el néctar de Fuchsia magellanica entre el abejorro invasor, Bombus terrestris (terr: la especie constructora), quien frecuentemente agujerea la base de tubos florales para robar néctar, y el abejorro nativo B. dahlbomii (dahl: la especie afectada), quien normalmente accede al néctar de Fuchsia en forma legítima a través de la apertura de la flor (visitas frontales). Los agujeros realizados por terr constituyen un caso de CNE, ya que persisten a lo largo de la vida de la vida de la flor (aprox. 7-day). En este trabajo relevamos la incidencia de flores robadas, la abundancia de las dos especies de abejas, y el número y tipo de sus visitas florales (frontales o de robo) día por medio durante 2.5 meses. Inicialmente terr accedió las flores de Fuchsia frontalmente, pero más tarde cambió su comportamiento convirtiéndose en un robador casi exclusivo a lo largo de un período de 10 días en que su abundancia se incrementó 20 veces (E2). En consecuencia, la incidencia de flores robadas varió positivamente con la abundancia de terr presente y pasada (E1). Por el contrario, la abundancia de dahl fue baja y varió negativamente con la incidencia de flores robadas (E3). En particular, la abundancia de dahl se incrementó seis veces en un período de 10 días una vez que terr cesó de visitar las flores de Fuchsia (E3), posiblemente porque dahl evitó la competencia con terr forrajeando en otras especies de plantas (E4). Cuando terr estuvo presente, dahl visitó las flores de Fuchsia frontalmente (tolerancia) o usó los agujeros existentes (adopción de comportamiento robador: E4). Estas respuestas diversas de dahl sugieren una compensación parcial de los efectos negativos de la competencia con terr. La CNE incrementa la asimetría de la competencia, favoreciendo la especie constructora. Sin embargo, las diferentes respuestas de las especies afectadas pueden compensar parcialmente esta desventaja competitiva, tal vez facilitando la coexistencia.

An analysis of plant–pollinator interactions reveals that the presence of abundant plant species favours the pollination of rare species. Such asymmetric facilitation might promote the coexistence of species in diverse plant communities. Abundant plant species boost the pollination of rare plant species.

Pollinator decline has attracted global attention, and substantial efforts are underway to respond, through national pollinator strategies and action plans. These policy responses require clarity on what is driving pollinator decline, and what risks it generates for society, in different parts of the world. Using a formal expert elicitation process, we evaluated relative regional and global importance of eight pressures driving pollinator decline, and ten consequent risks to human well-being. Our results indicate that global policy responses should focus on reducing pressure from changes in land cover and configuration, land management, and pesticides, as these were considered very important drivers in most regions. We quantify for the first time how the importance of drivers, and risks from pollinator decline, differ among regions. For example, losing access to managed pollinators was only considered a serious risk to people in North America, whereas yield instability in pollinator-dependent crops, classed as a serious or high risk in four regions, presented only moderate risk in Europe and North America. Overall, perceived risks were substantially higher in the Global South. Despite extensive, research on pollinator decline, our analysis reveals considerable scientific uncertainty about what this means for human society.

Fil: Aizen, Marcelo A. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Aizen, Marcelo A. Consejo Nacional de Investigaciones Científicas y Técnica. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Arbetman, Marina P. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Arbetman, Marina P. Consejo Nacional de Investigaciones Científicas y Técnica. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Chacoff, Natacha P. Universidad Nacional de Tucumán. Instituto de Ecología Regional; Argentina. Fil: Chalcoff, Vanina R. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Chalcoff, Vanina R. Consejo Nacional de Investigaciones Científicas y Técnica. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Feinsinger, Peter. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Centro de Estudio y Aplicación del Ciclo de Indagación; Argentina. Fil: Garibaldi, Lucas A. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Garibaldi, Lucas A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Harder, Lawrence D. University of Calgary. Department of Biological Sciences; Canada. Fil: Morales, Carolina L. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Morales, Carolina L. Consejo Nacional de Investigaciones Científicas y Técnica. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Sáez, Agustín. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Sáez, Agustín. Consejo Nacional de Investigaciones Científicas y Técnica. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Vanbergen, Adam J. Université de Bourgogne Franche-Comté. AgroSup Dijon; Francia. Increasing honey demand and global coverage of pollinator-dependent crops within the context of global pollinator declines have accelerated international trade in managed bees. Bee introductions into agricultural landscapes outside their native ranges have triggered noteworthy invasions, especially of the African honey bee in the Americas and the European bumble bee Bombus terrestris in southern South America, New Zealand, Tasmania, and Japan. Such invasions have displaced native bees via competition, pathogen transmission, and invaders' capacity to exploit anthropogenic landscapes. At high abundance, invasive bees can degrade the mutualistic nature of many of the flower-pollinator interactions they usurp, either directly by affecting flower performance or indirectly by reducing the pollination effectiveness of other flower visitors, with negative consequences for crop pollination and yield. We illustrate such effects with empirical examples, focusing particularly on interactions in the Americas between B. terrestris and raspberry and between the African honey bee and coffee. Despite high bee abundance and flower visitation in crops, theoretical and empirical evidence suggests that agricultural landscapes of pollinator-dependent crops dominated by invasive bees will be less productive than landscapes with more diverse pollinator assemblages. Safeguarding future crop yield and aiding the transition to more sustainable agricultural landscapes and practices require we address this impact of invasive bees. Actions include tighter regulation of the trade in bees to discourage further invasions, reducing invasive bee densities and dominance, and active enhancement of ecological infrastructure from field to landscape scales to promote wild bee abundance and diversity for sustained delivery of crop pollination services.

Wild pollinators are declining and the number of managed honey bee colonies is growing slower than agricultural demands for pollination. Because of these contrasting trends in pollinator demand and availability, breeding programs for many pollinator-dependent crops have focused on reducing the need for pollinators. Although numerous crop varieties are now available in the market with the label of pollinator-independent, the real dependence of these varieties on pollinators is mostly unknown. We evaluated the hypothesis of pollinator independence in the Independence almond variety, the fastest growing variety in California that is the main almond production region in the world. In this presumed pollinator-independent variety, we measured the effect of honey bees on fruit set, yield, and kernel nutritional quality at tree level. Fruit set was 60% higher in bee-pollinated than bee-isolated trees, which translated into a 20% increase in kernel yield. Despite its effect on almond production, there was no evidence that bee visitation affected almond nutritional quality. Based on these results, we recommend the use of bees, whether they are wild or managed, to maximize yield even in self-fertile almond varieties. Fil: Sáez, Agustín. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Departamento de Ecología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Aizen, Marcelo Adrian. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Departamento de Ecología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Medici, Sandra Karina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones en Sanidad Producción y Ambiente. - Comisión de Investigaciones Científicas de la Provincia de Buenos Aires. Instituto de Investigaciones en Sanidad Producción y Ambiente; Argentina Fil: Viel, Matias. Smart Pollination Services; Estados Unidos Fil: Villalobos, Ethel. University of Hawaii. Department of Plant and Environmental Sciences; Estados Unidos Fil: Negri, Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones en Sanidad Producción y Ambiente. - Comisión de Investigaciones Científicas de la Provincia de Buenos Aires. Instituto de Investigaciones en Sanidad Producción y Ambiente; Argentina

Fil: Pérez Méndez, Néstor. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Pérez Méndez, Néstor. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Pérez Méndez, Néstor. Institut de Recerca i Tecnologia Agroalimentàries. Estació Experimental de l'Ebre; España. Fil: Andersson, Georg K. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Andersson, Georg K. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Andersson, Georg K. Lund University. Centre for Environmental and Climate Research; Suecia. Fil: Requier, Fabrice. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Requier, Fabrice. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Requier, Fabrice. Université Paris-Sud. Evolution Génome Comportement et Ecologie; Francia. Fil: Hipólito, Juliana. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Hipólito, Juliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Hipólito, Juliana. Instituto Nacional de Pesquisas da Amazônia; Brasil. Fil: Aizen, Marcelo A. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Aizen, Marcelo A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Morales, Carolina. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Morales, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: García, Nancy. Agencia de desarrollo económico del Neuquén. Centro Pyme Adeneu; Argentina. Fil: Gennari, Gerardo P. Instituto Nacional de Tecnología Agropecuaria. Estación Experimental Agropecuaria Famaillá; Argentina. Fil: Garibaldi, Lucas Alejandro. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Garibaldi, Lucas Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. The alarming loss of pollinator diversity world‐wide can reduce the productivity of pollinator‐dependent crops, which could have economic impacts. However, it is unclear to what extent the loss of a key native pollinator species affects crop production and farmer's profits. By experimentally manipulating the presence of colonies of a native bumblebee species Bombus pauloensis in eight apple orchards in South Argentina, we evaluated the impact of losing natural populations of a key native pollinator group on (a) crop yield, (b) pollination quality, and (c) farmer's profit. To do so, we performed a factorial experiment of pollinator exclusion (yes/no) and hand pollination (yes/no). Our results showed that biotic pollination increased ripe fruit set by 13% when compared to non‐biotic pollination. Additionally, fruit set and the number of fruits per apple tree was reduced by less than a half in those orchards where bumblebees were absent, even when honeybees were present at high densities. Consequently, farmer's profit was 2.4‐fold lower in farms lacking bumblebees than in farms hosting both pollinator species. The pollination experiment further suggested that the benefits of bumblebees could be mediated by improved pollen quality rather than quantity. Synthesis and applications. This study highlights the pervasive consequences of losing key pollinator functional groups, such as bumblebees, for apple production and local economies. Adopting pollinator‐friendly practices such as minimizing the use of synthetic inputs or restoring/maintaining semi‐natural habitats at farm and landscape scales, will have the double advantage of promoting biodiversity conservation, and increasing crop productivity and profitability for local farmers. Yet because the implementation of these practices can take time to deliver results, the management of native pollinator species can be a provisional complementary strategy to increase economic profitability of apple growers in the short term. La alarmante pérdida de polinizadores que acontece a escala global puede reducir la productividad y el potencial económico de muchos cultivos entomófilos (p.ej. frutales). Sin embargo, aún no está claro hasta qué punto la pérdida de una única especie (o grupo funcional) puede afectar al rendimiento del cultivo y al beneficio económico del agricultor. Se manipuló experimentalmente la presencia de una especie de abejorro nativo Bombus pauloensis en ocho fincas de manzano en el sur de Argentina, para evaluar cómo la pérdida de las poblaciones nativas de este grupo de polinizadores (abejorros) afecta a (a) el rendimiento del cultivo, (b) a la calidad de la polinización y (c) al rendimiento económico del cultivo. Para ello, llevamos a cabo además un experimento factorial de exclusión de polinizadores (sí/no) y suplemento manual de polen (sí/no). Nuestros resultados muestran que la polinización biótica, es decir mediada por polinizadores, incrementó el cuajado de frutos maduros en un 13% respecto a la polinización abiótica (sin polinizadores). Además, el cuajado y el número de frutos por manzano se redujo a más de la mitad en aquellas fincas donde, a pesar de que la abeja de la miel estaba presente en altas densidades, el abejorro nativo estaba ausente. Como consecuencia, el beneficio económico para el agricultor en estas fincas fue 2.4 veces menor que en aquellas donde la abeja de la miel y el abejorro nativo estaban presentes simultáneamente. Nuestro experimento sugiere que la mejora del rendimiento aportada por los abejorros nativos está mediada por una mejora en la calidad del polen más que por un incremento en la cantidad. Síntesis y aplicaciones. Este estudio muestra las consecuencias negativas que van emparejadas a la pérdida de grupos de polinizadores clave, como los abejorros, en la producción de manzana y en el beneficio económico del agricultor. La adopción de prácticas agrícolas amigables con los polinizadores, como la reducción de agroquímicos o la restauración y mantenimiento de hábitats seminaturales a escala local y a escala de paisaje, se espera que tenga la doble ventaja de promover, por un lado, la conservación de la biodiversidad y, por otro, incrementar la productividad y el rendimiento económico para los productores. Dado que estas prácticas pueden tardar un tiempo en dar resultados, el manejo de especies nativas de polinizadores puede ser una estrategia provisional y complementaria para reducir, a corto plazo, el impacto económico para el agricultor.

Fil: Vanbergen, Adam J. Université de Bourgogne Franche-Comté. AgroSup Dijon. Agroécologie. Francia. Fil: Aizen, Marcelo A. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente. Rio Negro, Argentina. Fil: Aizen, Marcelo A. Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina. Instituto de Investigaciones en Biodiversidad y Medioambiente. Rio Negro, Argentina. Fil: Cordeau, Stephane. Université de Bourgogne Franche-Comté. AgroSup Dijon. Agroécologie. Francia. Fil: Garibaldi, Lucas A. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Garibaldi, Lucas A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural. Río Negro, Argentina. Fil: Garratt, Michael P. D. Reading University. School of Agriculture, Policy and Development. Centre for Agri-Environmental Research. Reino Unido. Fil: Kovács-Hostyánszki, Anikó. Institute of Ecology and Botany. Centre for Ecological Research. Hungría. Fil: Lecuyer, Lou. Université de Bourgogne Franche-Comté. AgroSup Dijon. Agroécologie. Francia. Fil: Ngo, Hien T. Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services. Alemania. Fil: Potts, Simon G. Reading University. School of Agriculture, Policy and Development. Centre for Agri-Environmental Research. Reino Unido. Fil: Settele, Josef. Helmholtz Centre for Environmental Research. Department of Community Ecology. Alemania. Fil: Skrimizea, Eirini. Université de Bourgogne Franche-Comté. AgroSup Dijon. Agroécologie. Francia. Fil: Young, Juliette C. Université de Bourgogne Franche-Comté. AgroSup Dijon. Agroécologie. Francia. Multiple anthropogenic challenges threaten nature's contributions to human well-being. Agricultural expansion and conventional intensification are degrading biodiversity and ecosystem functions, thereby undermining the natural foundations on which agriculture is itself built. Averting the worst effects of global environmental change and assuring ecosystem benefits, requires a transformation of agriculture. Alternative agricultural systems to conventional intensification exist, ranging from adjustments to efficiency (e.g. sustainable intensification) to a redesign (e.g. ecological intensification, climate-smart agriculture) of the farm management system. These alternatives vary in their reliance on nature or technology, the level of systemic change required to operate, and impacts on biodiversity, landscapes and agricultural production. Different socio-economic, ecological and political settings mean there is no universal solution, instead there are a suite of interoperable practices that can be adapted to different contexts to maximise efficiency, sustainability and resilience. Social, economic, technological and demographic issues will influence the form of sustainable agriculture and effects on landscapes and biodiversity. These include: (1) the socio-technical-ecological architecture of agricultural and food systems and trends such as urbanisation in affecting the mode of production, diets, lifestyles and attitudes; (2) emerging technologies, such as gene editing, synthetic biology and 3D bioprinting of meat; and (3) the scale or state of the existing farm system, especially pertinent for smallholder agriculture. Agricultural transformation will require multifunctional landscape planning with cross-sectoral and participatory management to avoid unintended consequences and ultimately depends on people's capacity to accept new ways of operating in response to the current environmental crisis.

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 1980’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.