Functional resin use in solitary bees

Abstract

1. Overall, more than 30% of bee species depend on non‐floral resources, such as resin. However, the importance of resin in bee ecology, particularly for solitary bees, has received very little attention thus far. 2. A plethora of loose natural history observations, inferences, and author opinions hint towards a striking range of uses of resin for nesting by bees. In this review, we focus on resin use in solitary bees and identify extant knowledge, knowledge gaps, and future research directions with regard to the functional use of resin in bee nesting biology. 3. Resin use in solitary bee nests can be broadly grouped by functional roles for nest structure, chemical camouflage, defence, moisture regulation, and anti‐microbial properties. We point out that resin usage appears to be constrained by environmental and physiological factors. Bee species‐specific tolerances for resin toxicity and resin availability in the environment seem to determine resin choices and subsequently functional usage in nests. We finally highlight that resin may play a major role in determining the ambient nest microbiota, due to its strong antimicrobial properties. We conclude that a better mechanistic understanding of resin use in bee nesting biology can aid in assessing species range shifts in light of global change.

Open forest successional stages and landscape heterogeneity promote wild bee diversity in temperate forests

“…On average nestedness and turnover components did not differ significantly, which means on average all management types and therefore successional stages were important to promote wild bees. As early successional habitats harbored the most species‐rich wild bee communities, we deduct that unmanaged and close‐to‐nature plots probably have some structures like deadwood or resources like resin (Chui et al, 2021) which are important for some wild bee genera like, for example, Megachile or Hylaeus (Eckerter et al, 2021). Therefore, while early successional forests can be considered important for wild bee conservation in forests (Roberts et al, 2017), unmanaged forests which exhibit old‐growth characteristics such as large standing deadwood structures are also important.…”

“…), oak ( Quercus sp.) (Bertrand et al, 2019; Ulyshen et al, 2010) providing honeydew and resin (Cameron et al, 2019; Chui et al, 2021). Flowering resources present in forests are among the earliest throughout the year (Inari et al, 2012), and are important for bumblebee queens (Mola et al, 2021) and other early flying wild bees (Watson et al, 2011).…”

Forests are critically important to global pollinator diversity and enhance pollination in adjacent crops

“…(2) Non-floral plant resources: honeydew and resin With >30% of bee species globally depending on them, the conservation value of non-floral plant resources has been increasingly recognized in recent years (Requier & Leonhardt, 2020;Chui, Keller & Leonhardt, 2022). Although many non-floral resources are used by pollinators, honeydew and resins are of particular importance to pollinators in forests.…”

Environmental DNA as an emerging tool in botanical research

“…Furthermore, eDNA is collected via bulk environmental samples across an array of ecological contexts, including marine (Thomsen et al, 2012), freshwater (Jerde et al, 2011; Deiner et al, 2015), sediment/soil (Yoccoz et al, 2012; Parducci et al, 2017; Lin et al, 2021), and air (Johnson et al, 2019a). It can also be collected from various media including artifacts (Foley et al, 2012), animal legs (Arstingstall et al, 2021), feces (Wang et al, 2022), honey and resins (Chui et al, 2021), pitcher plant liquid (Littlefair et al, 2018) and flowers (Harper et al, 2022).…”