Ecology Letters. doi: 10.1111/j.1461-0248.2012.01740.x

Theory developed from studying changes in the structure and function of communities during natural or managed succession can guide the restoration of particular communities. We constructed 30 quantitative plant–flower visitor networks along a managed successional gradient to identify the main drivers of change in network structure. We then applied two alternative restoration strategies in silico (restoring for functional complementarity or redundancy) to data from our early successional plots to examine whether different strategies affected the restoration trajectories. Changes in network structure were explained by a combination of age, tree density and variation in tree diameter, even when variance explained by undergrowth structure was accounted for first. A combination of field data, a network approach and numerical simulations helped to identify which species should be given restoration priority in the context of different restoration targets. This combined approach provides a powerful tool for directing management decisions, particularly when management seeks to restore or conserve ecosystem function.

Science 13 January 2012: 335(6065): 174-175. DOI: 10.1126/science.1217245

How is the biodiversity within an ecosystem related to the ecosystem's function? Quantifying and understanding this relationship—the biodiversity-ecosystem function (BEF) (1)—is important because socio-economic development is almost always accompanied by the loss of natural habitat and species (2). Short-term economic gains may thus trump longer-term benefits for human society, creating vulnerabilities that could be avoided or corrected with enough knowledge about the role of biodiversity. Erosion of biodiversity at local and regional scales may also reduce resilience at larger spatial scales as a result of degradation of ecosystem function (3). On page 214 of this issue, Maestre et al. (4) report an important step toward extending our understanding of BEF to globally important ecosystems.

PLoS ONE 6(6): e21550. doi:10.1371/journal.pone.0021550

The honeybee, Apis mellifera, is undergoing a worldwide decline whose origin is still in debate. Studies performed for twenty years suggest that this decline may involve both infectious diseases and exposure to pesticides. Joint action of pathogens and chemicals are known to threaten several organisms but the combined effects of these stressors were poorly investigated in honeybees. Our study was designed to explore the effect of Nosema ceranae infection on honeybee sensitivity to sublethal doses of the insecticides fipronil and thiacloprid. After exposure to sublethal doses of fipronil or thiacloprid a higher mortality was observed in N. ceranae-infected honeybees than in uninfected ones. The synergistic effect of N. ceranae and insecticide on honeybee mortality, however, did not appear strongly linked to a decrease of the insect detoxification system. These data support the hypothesis that the combination of the increasing prevalence of N. ceranae with high pesticide content in beehives may contribute to colony depopulation.

Journal of the Kansas Entomological Society 84(4):260-270. 2011 doi: 10.2317/JKES110319.1

Insect pollinators provide a critical ecosystem service by pollinating many wild flowers and crops. It is therefore essential to be able to effectively survey and monitor pollinator communities across a range of habitats, and in particular, sample the often stratified parts of the habitats where insects are found. To date, a wide array of sampling methods have been used to collect insect pollinators, but no single method has been used effectively to sample across habitat types and throughout the spatial structure of habitats. Here we present a method of ‘aerial pan-trapping’ that allows insect pollinators to be sampled across the vertical strata from the canopy of forests to agro-ecosystems. We surveyed and compared the species richness and abundance of a wide range of insect pollinators in agricultural, secondary regenerating forest and primary forest habitats in Ghana to evaluate the usefulness of this approach. In addition to confirming the efficacy of the method at heights of up to 30 metres and the effects of trap color on catch, we found greatest insect abundance in agricultural land and higher bee abundance and species richness in undisturbed forest compared to secondary forest.

Course participation is free, but please register by sending organisers an e-mail. The participants need to cover their travel and accommodation costs. To register, contact: Piotr Nowicki (piotr.nowicki@uj.edu.pl).

Ecology Letters (2012) doi: 10.1111/j.1461-0248.2011.01729.x

Environmental changes threaten plant-pollinator mutualisms and their critical ecosystem service. Drivers such as land use, invasions and climate change can affect pollinator diversity or species encounter rates. However, nitrogen deposition, climate warming and CO2 enrichment could interact to disrupt this crucial mutualism by altering plant chemistry in ways that alter floral attractiveness or even nutritional rewards for pollinators. Using a pumpkin model system, we show that these drivers non-additively affect flower morphology, phenology, flower sex ratios and nectar chemistry (sugar and amino acids), thereby altering the attractiveness of nectar to bumble bee pollinators and reducing worker longevity. Alarmingly, bees were attracted to, and consumed more, nectar from a treatment that reduced their survival by 22%. Thus, three of the five major drivers of global environmental change have previously unknown interactive effects on plant-pollinator mutualisms that could not be predicted from studies of individual drivers in isolation.

Closing date for applications: 5 March, 2012.

Closing date for applications: February 15, 2012.

Closing date for applications: January 31, 2012.

International Journal for Parasitology, doi: 10.1016/j.ijpara.2011.10.005

7th European Conference on Biological Invasions

The progressing and escalating threats posed by invasive alien species in Europe suggest that inmediate cooperative, specific planning is necessary if we are to have any chanche to halt biodiversity loss. Scientific, technical, political and legal actions need to be put in place urgently in order to diminish the ecological and economic impacts of biological invasions. In this framework, NEOBIOTA 2012 will provide an international high-level forum to incorporate reserach into decision making processes an management of invasive alien species. NEOBIOTA will constitute an important opportunity to advance the dialogue and strengthen cooperation between the scientific community, conservation agencies, stakeholders, and policy and decision makers. Researchers, representatives from governmental entities, non-profit organizations, and any person or party involved in biodiversity conservation and natural resource management are invited to participate and share ideas, new results and opinions in the field of biological invasions.

Place: Halle an der Saale, Germany

PNAS (2011) doi: 10.1073/pnas.1115559108

The phenology of many ecological processes is modulated by temperature, making them potentially sensitive to climate change. Mutualistic interactions may be especially vulnerable because of the potential for phenological mismatching if the species involved do not respond similarly to changes in temperature. Here we present an analysis of climate-associated shifts in the phenology of wild bees, the most important pollinators worldwide, and compare these shifts to published studies of bee-pollinated plants over the same time period. We report that over the past 130 y, the phenology of 10 bee species from northeastern North America has advanced by a mean of 10.4 ± 1.3 d. Most of this advance has taken place since 1970, paralleling global temperature increases. When the best available data are used to estimate analogous rates of advance for plants, these rates are not distinguishable from those of bees, suggesting that bee emergence is keeping pace with shifts in host-plant flowering, at least among the generalist species that we investigated.