Bumblebee mites - Bumblebee Conservation Trust
a mutualistic symbiotic relationship between parasitic mites and the the relationship between the mite (Varroa destructor), honey bees and. Most bumblebees have many tiny mites clinging to their bodies. The good news is that most of the mite species that live with bumblebees are fairly harmless. conservation of bumble bees, given that commensals may become cleptoparasitic Ecological characteristics of insects that affect symbiotic relationships with.
Lately, attention has focused on the endoparasitic mite Locustacarus buchneri that has been found in commercial bumblebees. However, little is known of other mites associated with commercial bumblebee nests. Transportation of commercial bumblebee colonies with unwanted residents may introduce foreign mite species to new localities. In this study, we assessed the prevalence and species composition of mites associated with commercial bumblebee nests and determined if the mites are foreign species for Poland and for Europe.
The study was conducted on 37 commercial bumblebee nests from two companies Dutch and Israelioriginating from two greenhouses in southern Poland, and on 20 commercial bumblebee colonies obtained directly from suppliers.
The species composition and abundance of mites inhabiting commercial bumblebee nests were determined. Seven mite species from three families were found in nests after greenhouse exploitation. The predominant mite species was Tyrophagus putrescentiae Acaridae that was a fold more numerous than representatives of the family Laelapidae Hypoaspis marginepilosa, H.
Representatives of Parasitidae Parasitellus fucorum, P.
Symbionts of bumblebees
All identified mite species are common throughout Europe, foreign species were not found. Mites were not detected in nests obtained directly from suppliers. We conclude that probably bumblebee nests are invaded by local mite species during greenhouse exploitation.
Bombus terrestris, Acaridae, Laelapidae, Parasitidae, Invasive species, Commensal species Introduction Social and solitary bees are hosts to a wide diversity of mites Eickwort ; Klimov et al.
Acarine parasites of honeybees such as Acarapis woodi and Varroa destructor have been intensively studied as they are problematic pests that influence beekeeping and pollination services at a global scale Sammataro et al. Lately, more attention has been paid to bumblebee mite associates.
The rearing of bumblebee colonies at high densities in commercial companies provides an opportunity for various pathogens to develop and reach a higher prevalence than their counterparts in natural populations Colla et al. Moreover, European greenhouses import bumblebee colonies from outside of Europe Velthuis and Van Doorn which may facilitate the transportation of alien bumblebee-associated mites as well as other parasites and pathogens.
Research on bumblebee colonies has concentrated mainly on protozoan parasites, their effect on host fitness and possible treatments Imhoof and Schmid-Hempel ; Whittington and Winston ; Rutrecht and Brown ; Otti and Schmid-Hempel Some studies have detected protozoan parasites in the Canadian greenhouse bumblebee, Bombus occidentalis Whittington and Winstonand European commercial colonies of Bombus terrestris Niwa et al.
Others have shown that commercially bred bumblebees can pose a threat to local populations as vectors transmitting the protozoan parasites Nosema bombi and Crithidia bombi Colla et al.
Another example of a parasite disseminated with commercial bumblebee colonies is the endoparasitic mite Locustacarus buchneri. The mite feeds and reproduces mainly in the abdominal air sacks of adult queens and worker bumblebees Yoneda et al.
Individuals of this species, with a foreign genome, were found both among commercial colonies exported from Europe to Japan and among Japanese native bumblebee Bombus hypocrita Goka et al. Therefore this parasitic mite has been known from commercial bumblebees for a decade.
This tracheal mite is known to attack at least 25 wild bumblebee species across the Holarctic region Husband and Husband Locustacarus buchneri was also detected among commercial colonies of B. Although little is known about the influence of mites on bumblebees, it is considered as negative.
Parasitized bumblebees have shorter lifespans than unparasitized bees Otterstatter and Whidden Therefore studies detecting other species related to commercial bumblebee nests are needed. There are other mites associated with bumblebees that live and reproduce in bumblebee nests on resources such as nectar and pollen Schmid-Hempelbut have never been studied in commercial bumblebee nests. These mites presumably do not have a strong positive or negative effect on their host, as they are saprophagous or mostly fungivorous and a social insect nest is one of many potential habitats.
They are not exclusively dependent upon nourishment provided in the nest Eickwort ; Schmid-Hempel Some bumblebee-associated mites recorded from wild bumblebees are phoretic Schwarz et al. In such cases, the mite and host species exhibit synchronization of life cycles.
Bumblebees form annual colonies and only the young queens overwinter. Therefore, mites must attach themselves to new queens in autumn and accompany them to hibernation sites Eickwort ; Schwarz et al.
Even Bumblebees Get Mites, (Lots of Them) | Adventures in Natural Beekeeping
When an overwintered queen founds a new colony in the spring, the mites detach and colonize the new nest Goulson Four to six mite species may be found on an overwintering queen and more than 20 mite individuals may be present on one bumblebee Schwarz et al. Commercialization of bumblebees brings new opportunity for associated mite species to reproduce at high rates under favourable conditions, as commercial colonies are supplied with sugar solution and pollen Velthuis and Van Doorn Several years of intense investigation did not reveal a specific causal agent, but a multifactorial origin was proposed for this syndrome, which is often associated with high levels of parasites in combination with pathogens 24.
It was evident that the immunocompetence of honey bees in collapsing colonies was impaired, undermining their capacity to face the biotic stress factors occurring in the hive ecosystem. Indeed, a number of studies have identified important roles of the parasitic mite Varroa destructor 5 and vectored viral pathogens, particularly the deformed wing virus DWV 6in contributing to significant changes in the global viral landscape and a continuing decline in honey bee health 7 — 9.
We recently contributed to this research issue, proposing a functional model describing how the delicate immune balance underpinning the covert infections of DWV can be destabilized by Varroa feeding, resulting in intense viral proliferation Separate independent work further corroborated this evidence, showing that viral infection in honey bees interfered with the expression of genes that participate in the Toll pathway 11 This finding supports the hypothesis that in honey bees, and more generally in insects, inducible antiviral barriers besides RNAi-mediated mechanisms 11 — 18 may have an important role.
The occurrence, often asymptomatic, of DWV in nearly all honey bee colonies 6favored by the active vectoring activity of Varroa mite 5represents a constant threat that can become a severe problem in the presence of additional stress factors, such as, among others, pesticides and poor nutrition, which can promote viral replication 8 Therefore, multiple stress agents exert a synergistic action that compromises the delicate immune balance underpinning the covert DWV infections, and may well account for the multifactorial origin of colony losses.
Collectively, the available experimental evidence indicates that DWV adopts a virulence strategy, still obscure from a molecular standpoint, that targets antiviral barriers under control of the Toll pathway. The active role of V.
The feeding behavior of V. Any humoral and cellular immune reaction in the host, such as hemolymph clotting, melanization, or encapsulation, that directly interferes with food uptake and use may in principle result in reduced mite fitness. Therefore, based on current knowledge about DWV-induced immunosuppression, a positive influence of viral infection on mite feeding and reproduction can be hypothesized.
However, notwithstanding the key importance of the Varroa—DWV association, the intimate aspects of their interaction have been largely overlooked. Here we focus on the functional basis of this tight association, examining the impact of DWV infection on multiple immune barriers under the Toll pathway and assessing whether this has any effect on Varroa mite fitness.
These are very relevant issues that, if properly addressed, can provide mechanistic insights of key importance to understand the dynamics of mite—virus association and developing new strategies to alleviate its dramatic impact on honey bee colonies. To study the DWV-induced immunosuppression, we first assessed at the phenotypic level how the cellular and humoral components of the immune response vary across different DWV infection levels, irrespective of the presence of Varroa, in the absence of other viral pathogens.