Pollen–insect interaction meta‐networks identify key relationships for conservation in mosaic agricultural landscapes

Abstract

Flower visitors use different parts of the landscape through the plants they visit, however these connections vary within and among land uses. Identifying which flower‐visiting insects are carrying pollen, and from where in the landscape, can elucidate key pollen–insect interactions and identify the most important sites for maintaining community‐level interactions across land uses. We developed a bipartite meta‐network, linking pollen–insect interactions with the sites they occur in. We used this to identify which land‐use types at the site‐ and landscape‐scale (within 500 m of a site) are most important for conserving pollen–insect interactions. We compared pollen–insect interactions across four different land uses (remnant native forest, avocado orchard, dairy farm, rotational potato crop) within a mosaic agricultural landscape. We sampled insects using flight intercept traps, identified pollen carried on their bodies and quantified distinct pollen–insect interactions that were highly specialized to both natural and modified land uses. We found that sites in crops and dairy farms had higher richness of pollen–insect interactions and higher interaction strength than small forest patches and orchards. Further, many interactions involved pollinator groups such as flies, wasps, and beetles that are often under‐represented in pollen–insect network studies, but were often connector species in our networks. These insect groups require greater attention to enable wholistic pollinator community conservation. Pollen samples were dominated by grass (Poaceae) pollen, indicating anemophilous plant species may provide important food resources for pollinators, particularly in modified land uses. Field‐scale land use (within 100 m of a site) better predicted pollen–insect interaction richness, uniqueness, and strength than landscape‐scale. Thus, management focused at smaller scales may provide more tractable outcomes for conserving or restoring pollen–insect interactions in modified landscapes. For instance, actions aimed at linking high‐richness sites with those containing unique (i.e., rare) interactions by enhancing floral corridors along field boundaries and between different land uses may best aid interaction diversity and connectance. The ability to map interactions across sites using a meta‐network approach is practical and can inform land‐use planning, whereby conservation efforts can be targeted toward areas that host key interactions between plant and pollinator species.

Effective Behavior of Insects Pollinators of Flowers in Gadung Mango Clone 21 Variety

“…The results of the research were the fastest visit behavior and the highest number of flowers obtained from Trigona sp. i,e., (1.76 ± 0.23) (Hall et al 2022;Wäckers et al 2007).…”

Flower–bee versus pollen–bee metanetworks in fragmented landscapes

“…Alternatively, pollen loads analyses of flower visitors also provide valuable information regarding an animal’s capacity as a pollinator and are suitable for large-scale studies given their relative simplicity [21,22]. Pollen-transport networks have been studied at singular sites and local scales [23–26] and pollen metanetworks across land-use types [27], but, to our knowledge, there is no study analysing pollen-transport networks and metanetworks over gradients of habitat size, isolation and landscape diversity.…”

Social but not solitary bee abundance tracks pollen protein accumulation in forest canopy gaps

“…In forested ecosystems, restoration methods such as thinning evenly throughout a stand or clumped thinning (gap creation) can benefit native bee communities by creating open forest conditions (Hanula et al, 2016). These changes in forest structure can alter bee–flower interactions by promoting recruitment of floral resources, often resulting in increased specialisation (Hall et al, 2022). Interpreting bee life history and functional traits—such as body size, nesting behaviour and sociality—can inform our understanding of how and why canopy gaps affect specific groups of bees and bee–flower interactions (Williams et al, 2010).…”