Flight behaviour of honey bee (Apis mellifera) workers is altered by initial infections of the fungal parasite Nosema apis

Abstract

Honey bees (Apis mellifera) host a wide range of parasites, some being known contributors towards dramatic colony losses as reported over recent years. To counter parasitic threats, honey bees possess effective immune systems. Because immune responses are predicted to cause substantial physiological costs for infected individuals, they are expected to trade off with other life history traits that ultimately affect the performance and fitness of the entire colony. Here, we tested whether the initial onset of an infection negatively impacts the flight behaviour of honey bee workers, which is an energetically demanding behaviour and a key component of foraging activities. To do this, we infected workers with the widespread fungal pathogen Nosema apis, which is recognised and killed by the honey bee immune system. We compared their survival and flight behaviour with non-infected individuals from the same cohort and colony using radio frequency identification tags (RFID). We found that over a time frame of four days post infection, Nosema did not increase mortality but workers quickly altered their flight behaviour and performed more flights of shorter duration. We conclude that parasitic infections influence foraging activities, which could reduce foraging ranges of colonies and impact their ability to provide pollination services.

Probabilistic assessment of nectar requirements for nectar-foraging honey bees

“…The number of trips taken in a given day by a nectar forager varies among subspecies, colonies, individuals, and temporally for each individual depending on the age and health of the forager, colony needs, available resources, and weather conditions (reviewed in Rodney and Purdy, this issue). The most comprehensive data currently available for the frequency of trips taken by workers is based on radio-frequency identification (RFID) tracking of individual bees over extended periods of time, typically days to weeks (Thompson et al 2016;Dosselli et al 2016). The results are presented as averages of individual bees over numerous flying days.…”

“…Based on quantitative data from five studies, a mean of 2.91 ± 2.50 trips per day was calculated for T (n = 2713 for sample mean, n = 2257 for sample standard deviation; Heberle 1914;Thom et al 2000;Lach et al 2015;Dosselli et al 2016;Thompson et al 2016; Online Resource 1, Table S1-1 Data used to estimate the distribution parameters for the number of trips per day (T ) taken by honey bee nectar foragers in the RARI model). Other studies did not report sample size or variance but did report mean flights per bee per day of between 7 and 13.5 trips (Park 1922;Lundie 1925) with single day maxima of 17 and 24, for bees foraging on white clover in Iowa (Park 1922).…”

Effects of parasites and pathogens on bee cognition

“…have reduced foraging performances when compared with uninfected conspecifics. Parasitised foragers show an increased activity (Dussaubat et al ., ; Alaux et al ., ; Wells et al ., ), by performing more foraging trips of shorter duration with many stops between them (Dussaubat et al ., ; Wolf et al ., ; Dosselli et al ., ), and spending more time outside the colony (Kralj & Fuchs, ). In addition, honey bees infected with the DWV virus show reduced flight distances and durations when tested in a flight mill arm (Wells et al ., ).…”

Parasitic gut infection causes functional and molecular resemblance of Libellula pulchella dragonfly flight muscle to skeletal muscle of obese vertebrates

“…Studies of the effects of parasitic infections on insect flight performance traits have focused mainly on mosquitos and honeybees (e.g. Rowland and Boersma, 1988;Yee and Anderson, 1995;Wolf et al, 2014;Dosselli et al, 2016;Newman, Anderson, and Goldberg, 2016;Dussaubat et al, 2013; but see Altizer et al, 2015), but mechanistic details of infection effects are rarely studied (but see Harrison et al, 2001).…”