More Like this

1. Data from: Seed mix design and floral resources drive multi-trophic interactions in prairie restoration

   https://doi.org/10.5061/dryad.zpc866tg0  

   Hulting, Katherine; Kemmerling, Lindsey; Griffin, Sean; Webb, Jessica; Brown, Ally; Haddad, Nick (January 2024, Dryad)

   Ecological restoration often targets plant community recovery, but restoration success may depend on the recovery of a complex web of biotic interactions to maintain biodiversity and promote ecosystem services. Specifically, management that drives resource availability, such as seeding richness and provenance, may alter species interactions across multiple trophic levels. Using experimentally seeded prairies, we examine three key groups – plants, pollinators, and goldenrod crab spiders (Misumena vatia, predators of pollinators) – to understand the effects of species richness and admixture seed sourcing of restoration seed mixtures on multi-trophic interactions. Working with prairie plants, we experimentally manipulated seed mix richness and the number of seed source regions (single-source region or admixture seed sourcing). In each experimental prairie, we surveyed floral abundance and richness, pollinator visitation, and plant-M. vatia interactions. A high-richness seed mix increased floral abundance when seeds were sourced from a single geographic region, and floral abundance strongly increased pollinator visitation, M. vatia abundance, and prey capture. Seeding richness and admixture seed sourcing of the seed mixture did not affect floral species richness, but floral species richness increased pollinator visitation. Pollinators interacted with different floral communities across seeding treatments, indicating a shift in visited floral species with restoration practices. Synthesis and applications. Long-term success in prairie restoration requires the restoration of plant-arthropod interactions. We provide evidence that seed mix richness and admixture seed sourcing affect arthropod floral associations, but effective restoration of plant-arthropod interactions should consider total floral resource availability. Incorporating a food web perspective in restoration will strengthen approaches to whole ecosystem restoration. 

   more » « less
2. Experimental Test of the Combined Effects of Water Availability and Flowering Time on Pollinator Visitation and Seed Set

   https://doi.org/10.3389/fevo.2021.641693  

   Gallagher, M. Kate; Campbell, Diane R. (March 2021, Frontiers in Ecology and Evolution)

   Climate change is likely to alter both flowering phenology and water availability for plants. Either of these changes alone can affect pollinator visitation and plant reproductive success. The relative impacts of phenology and water, and whether they interact in their impacts on plant reproductive success remain, however, largely unexplored. We manipulated flowering phenology and soil moisture in a factorial experiment with the subalpine perennial Mertensia ciliata (Boraginaceae). We examined responses of floral traits, floral abundance, pollinator visitation, and composition of visits by bumblebees vs. other pollinators. To determine the net effects on plant reproductive success, we also measured seed production and seed mass. Reduced water led to shorter, narrower flowers that produced less nectar. Late flowering plants produced fewer and shorter flowers. Both flowering phenology and water availability influenced pollination and reproductive success. Differences in flowering phenology had greater effects on pollinator visitation than did changes in water availability, but the reverse was true for seed production and mass, which were enhanced by greater water availability. The probability of receiving a flower visit declined over the season, coinciding with a decline in floral abundance in the arrays. Among plants receiving visits, both the visitation rate and percent of non-bumblebee visitors declined after the first week and remained low until the final week. We detected interactions of phenology and water on pollinator visitor composition, in which plants subject to drought were the only group to experience a late-season resurgence in visits by solitary bees and flies. Despite that interaction, net reproductive success measured as seed production responded additively to the two manipulations of water and phenology. Commonly observed declines in flower size and reward due to drought or shifts in phenology may not necessarily result in reduced plant reproductive success, which in M. ciliata responded more directly to water availability. The results highlight the need to go beyond studying single responses to climate changes, such as either phenology of a single species or how it experiences an abiotic factor, in order to understand how climate change may affect plant reproductive success. 

   more » « less
3. Transient dynamics in plant–pollinator networks: fewer but higher quality of pollinator visits determines plant invasion success

   https://doi.org/10.1111/oik.09634  

   Valdovinos, Fernanda S.; Dritz, Sabine; Marsland, Robert (June 2023, Oikos)

   Invasive plants often use mutualisms to establish in their new habitats and tend to be visited by resident pollinators similarly or more frequently than native plants. The quality and resulting reproductive success of those visits, however, have rarely been studied in a network context. Here, we use a dynamic model to evaluate the invasion success and impacts on natives of various types of non‐native plant species introduced into thousands of plant–pollinator networks of varying structure. We found that network structure properties did not predict invasion success, but non‐native traits and interactions did. Specifically, non‐native plants producing high amounts of floral rewards but visited by few pollinators at the moment of their introduction were the only plant species able to invade the networks. This result is determined by the transient dynamics occurring right after the plant introduction. Successful invasions increased the abundance of pollinators that visited the invader, but the reallocation of the pollinators' foraging effort from native plants to the invader reduced the quantity and quality of visits received by native plants and made the networks slightly more modular and nested. The positive and negative effects of the invader on pollinator and plant abundance, respectively, were buffered by plant richness. Our results call for evaluating the impact of invasive plants not only on visitation rates and network structure, but also on processes beyond pollination including seed production and recruitment of native plants. 

   more » « less
4. Pollinator visitation, flower count, and seed set in Black Sand plots, 2020.

   https://doi.org/10.6073/pasta/813cfb86337d8aea942946cc470dcfff  

   Rose-Person, Annika; Spasojevic, Marko J; Forrester, Chiara C; Bowman, William D; Suding, Katharine N; Oldfather, Meagan F; Rafferty, Nicole E (August 2025, Environmental Data Initiative)

   Anthropogenic climate change is altering interactions among numerous species, including plants and pollinators. Plant-pollinator interactions, crucial for the persistence of most plant and many insect species, are threatened by climate change-driven phenological shifts. Phenological mismatches between plants and their pollinators may affect pollination services, and simulations indicated that these mismatches may reduce floral resources available to up to 50% of insect pollinator species. Although alpine plants rely heavily on vegetative reproduction, seedling recruitment and seed dispersal are likely to be important drivers of alpine community structure. Similarly, advanced flowering may expose plants to increased risk of frost damage and shifted soil moisture regimes; phenologically advanced plants will experience these environmental factors differently, which may alter their floral resource production. These effects may be dependent upon topography. Some species of alpine plants on the Niwot Ridge have displayed advanced phenology under treatments of advanced snowmelt (Forrester, 2021). However, little is understood about how these differences in distribution and phenology affect pollinator community composition and plant fecundity. Here we strive to examine how experimentally-induced changes in the timing of flowering and number of flowers produced by plants impact plant-pollinator interactions and seed set. We also ask how topography and the number of flowers interact with early snowmelt to affect pollination rates and the diversity of pollinating insects. Finally, we ask how seed set of Geum rossii is affected by pollinator visitation at different times of the season, under experimentally advanced snowmelt versus unmanipulated snowmelt, and with visitation by different insect taxa. In summer 2020, we found that plots with advanced phenology experienced peaks in pollinator visitation rates and pollinator diversity earlier than plots with unmanipulated snowmelt. We expect this to be because of the advanced floral phenology of certain key species in these plots. References: Forrester, C.C. (2021). Advancing, Using, and Teaching Climate Change Ecology Research. [Doctoral dissertation, University of Colorado, Boulder]. ProQuest Dissertations and Theses. 

   more » « less
5. Early snowmelt advances flowering phenology and disrupts the drivers of pollinator visitation in an alpine ecosystem

   https://doi.org/10.1007/s00035-024-00315-x  

   Rose-Person, Annika; Spasojevic, Marko J; Forrester, Chiara; Bowman, William D; Suding, Katharine N; Oldfather, Meagan F; Rafferty, Nicole E (June 2024, Alpine Botany)

   Abstract Climate change is altering interactions among plants and pollinators. In alpine ecosystems, where snowmelt timing is a key driver of phenology, earlier snowmelt may generate shifts in plant and pollinator phenology that vary across the landscape, potentially disrupting interactions. Here we ask how experimental advancement of snowmelt timing in a topographically heterogeneous alpine-subalpine landscape impacts flowering, insect pollinator visitation, and pathways connecting key predictors of plant-pollinator interaction. Snowmelt was advanced by an average of 13.5 days in three sites via the application of black sand over snow in manipulated plots, which were paired with control plots. For each forb species, we documented flowering onset and counted flowers throughout the season. We also performed pollinator observations to measure visitation rates. The majority (79.3%) of flower visits were made by dipteran insects. We found that plants flowered earlier in advanced snowmelt plots, with the largest advances in later-flowering species, but flowering duration and visitation rate did not differ between advanced snowmelt and control plots. Using piecewise structural equation models, we assessed the interactive effects of topography on snowmelt timing, flowering phenology, floral abundance, and pollinator visitation. We found that these factors interacted to predict visitation rate in control plots. However, in plots with experimentally advanced snowmelt, none of these predictors explained a significant amount of variation in visitation rate, indicating that different predictors are needed to understand the processes that directly influence pollinator visitation to flowers under future climate conditions. Our findings demonstrate that climate change-induced early snowmelt may fundamentally disrupt the predictive relationships among abiotic and biotic drivers of plant-pollinator interactions in subalpine-alpine environments. 

   more » « less