Meeting Abstract
Native bees are critical pollinators in diverse ecosystems. Recently detected declines in bee populations may therefore have serious ecological and economic implications. Parasites may be a primary driver of declines in many native bees, but the physiological mechanisms underlying the effects of parasites on bee populations are still poorly understood. Parasites may challenge host physiology in several ways. They may weaken the host by consuming the host’s energy reserves and by inducing a host immune response both to the parasites themselves and to any pathogens they vector. These combined effects can reduce performance and survival of individuals and may ultimately limit population viability. The outcome of this interaction between native bees and their parasites may be mediated in part by environmental temperatures, with implications for geographic and temporal variation in persistence of native bee populations. We investigated the largely unexplored effects of environmental temperature on bee-parasite interactions in Annapurna Conservation Area (ACA), Nepal. In samples of two ecologically and culturally important honey bees (Apis laboriosa and Apis cerana) collected from an altitudinal (and therefore temperature) gradient within the ACA, we measured loads and prevalence of four major bee pathogens and parasites (Varroa jacobsoni, Acarapis woodii, Nosema spp., and Crithidia spp.), and studied the effects of parasite load on lipid, sugar and glycogen content of individual bees. These results will help elucidate the effects of environmental temperatures on population-level impacts of parasites on native bees, providing critical insight into how native bee populations may respond to rising global temperatures.
