Parasitism in the social bee Apis mellifera: quantifying costs and benefits of behavioral resistance to Varroa destructor mites

Abstract

-The case of a host-parasite relationship may provide a good model to evaluate the costs and benefits of some behaviors, an area in which field data a currently lacking. European (EHB) and Africanized (AHB) honey bees are two Apis mellifera subspecies that coexist in Mexico, the former highly compatible with Varroa destructor, the latter less compatible. Here we examine two mechanisms that could explain the low compatibility between AHB and V. destructor in Mexico: (1) grooming behavior appeared significantly more intensive in AHB colonies, but was nevertheless ineffective; (2) EHB removed 8.03% of the infested brood, while AHB removed 32.46%, especially between 5 and 7 days post-capping. Though the cost of removing infested brood was not different between subspecies, the result, in terms of the amount of removed infested brood, was significantly higher for AHB. For both bees, there is thus a real cost, since removing a pupa results in a lower number of adult bees. We discuss the possibility that the removal of infested brood corresponds with a threshold above which the cost of removal becomes greater than the benefit.Apis mellifera / Varroa destructor / parasitology / costs and benefits / behavioral resistance

Africanized honey bees (Apis mellifera) have low infestation levels of the mite Varroa destructor in different ecological regions in Mexico

“…Low rates of mite infestation in African-derived honey bee colonies have been associated with a number of factors, including high swarming and migratory behavior (Otis, 1991), high levels of expression of hygienic behavior (Guerra Jr. et al, 2000;Vandame et al, 2002) or grooming behavior (Moretto et al, 1993(Moretto et al, , 1997Arechavaleta-Velasco and Guzmán-Novoa, 2001;Guzmán-Novoa et al, 2012), reduced susceptibility to mite invasion and reproduction (Ritter and De Jong, 1984;Guzmán-Novoa et al, 1996;Medina and Martin, 1999;Mondragón et al, 2006), reduced cell size (Message and Gonçalves, 1995;Piccirillo and De Jong, 2003), and other factors of less relevance.…”

Varroa-specific hygienic behavior of Apis mellifera scutellata in Kenya

“…VSH behavior is the refined ability of honey bees to detect, uncap, and remove mite-infested brood leading to high mite infertility (Harbo and Harris 2005;Ibrahim and Spivak 2006). It is a heritable and highly variable trait which has been used in programs to breed strain of honey bees of European origin, resulting in diverse honey bee populations that are desirable for bee keeping (Guerra Jr. et al 2000;Vandame et al 2002;Ibrahim and Spivak 2006;Harris 2007). Hygienic bees remove affected brood most likely by detecting odor cues emanating from infested hosts, when these cues exceed the response threshold of the bees within the colony (Masterman et al 2001;Martin et al 2002).…”

Impact of Varroa destructor on honeybee (Apis mellifera scutellata) colony development in South Africa

“…In Brazil, Varroa mite infestation rates of Africanised honeybee colonies have remained very low over the years, from when the mite was first observed in the late seventies up until recent times (Rosenkranz 1999), with no reports of large scale honeybee mortality (De Jong et al 1984;Camazine and Morse 1988;Carneiro et al 2007;Calderón et al 2010). In general, tolerance to Varroa mites in Africanised honeybees has been attributed to the presence of a large number of infertile female mites (Camazine 1986;Rosenkranz and Engels 1994), the uncapping and removal of mite infested brood (Corrêa-Marques and De Jong 1998;Guerra et al 2000;Vandame et al 2002) and the mortality of both male and female mite offspring, which decreases the reproductive output of the mites (Medina and Martin 1999;Mondragón et al 2005;Mondragón et al 2006). In African populations, tolerance mechanisms have not been studied as extensively, but possible reasons for Varroa mite tolerance have been attributed to a short post-capping stage, good hygienic and grooming behaviour and high absconding and swarming rates (Moritz and Hänel 1984;Moritz 1985;Boecking and Ritter 1993;Allsopp 2006;Frazier et al 2010).…”