The Early Season Community of Flower-Visiting Arthropods in a High-Altitude Alpine Environment

Abstract

In mountain ecosystems, climate change can cause spatiotemporal shifts, impacting the composition of communities and altering fundamental biotic interactions, such as those involving flower-visiting arthropods. On of the main problems in assessing the effects of climate change on arthropods in these environments is the lack of baseline data. In particular, the arthropod communities on early flowering high-altitude plants are poorly investigated, although the early season is a critical moment for possible mismatches. In this study, we characterised the flower-visiting arthropod community on the early flowering high-altitude Alpine plant, Androsace brevis (Primulaceae). In addition, we tested the effect of abiotic factors (temperature and wind speed) and other variables (time, i.e., hour of the day, and number of flowers per plant) on the occurrence, abundance, and diversity of this community. A. brevis is a vulnerable endemic species growing in the Central Alps above 2000 m asl and flowering for a very short period immediately after snowmelt, thus representing a possible focal plant for arthropods in this particular moment of the season. Diptera and Hymenoptera were the main flower visitors, and three major features of the community emerged: an evident predominance of anthomyiid flies among Diptera, a rare presence of bees, and a relevant share of parasitoid wasps. Temperature and time (hour of the day), but not wind speed and number of flowers per plant, affected the flower visitors’ activity. Our study contributes to (1) defining the composition of high-altitude Alpine flower-visiting arthropod communities in the early season, (2) establishing how these communities are affected by environmental variables, and (3) setting the stage for future evaluation of climate change effects on flower-visiting arthropods in high-altitude environments in the early season.

Impact of glacier retreat on biodiversity and plant–insect interaction dynamics

“…This is also consistent with the study about the dominance of flies as flower visitors in the Alps high-altitude (Lefebvre et al, 2018). The same trend was observed in the study of Bonelli et al with added information about the effects of temperature and time (hour of the day) in the flowering visitation of insects while wind speed and the number of flowers per plant did not influence (Bonelli et al, 2022).…”

“…Furthermore, plant community was a stronger predictor of network complexity and interaction diversity than the insect community (Robinson et al, 2018). Additionally, Bonelli et al reported the effect of temperature and time (hour of the day), but not wind speed and the number of flowers per plant on the flowervisiting of arthropods (Bonelli et al, 2022). Yet, it is not clear how interaction diversity changes with glacier retreat.…”

“…Like the two components of the interaction, plant-insect interaction networks are very sensitive to the changes in environmental conditions as well as the distribution of interacting partners (Adedoja et al, Bonelli et al, 2022). Plant-insect interactions are generally complex and reflect the functioning and health of the ecosystem (Adedojia et al, Losapio et al, 2020;Badenes-Pérez, 2022;Bonelli et al, 2022). The relationship between plants and insects has different components.…”

“…Although plants and insects are both among the primary pioneers in ecological succession, research on plant and insect communities along glacier retreats were studied independently and tended to focus on plants (Whittaker 1993;Chapin et al, 1994;Dullinger et al, 2012;Trunschke and Sto cklin, 2017;Llambí et al, 2021;Bonelli et al, 2022;Brochmann et al, 2022). More recent studies on ecological succession after glacier retreat have supplemented advances in research of community dynamics by using distribution, functional, and network theories .…”

Seasonal dynamics of floral composition and flower visitors in a subtropical alpine ecosystem in Taiwan

“…These unpredictable patterns might reflect the species-specific lifecycle of dipteran insects (Larson et al, 2001;Rotheray & Gilbert, 2011). Dipteran insects are known as important pollinators early in the season in European Alps (Bonelli et al, 2022) and high Arctic regions (Kevan, 1972;Tiusanen et al, 2016), indicating the importance of fly pollinators under harsh environmental conditions (Inouye et al, 2015).…”