title: Varroa destructor reproduction during the winter in Apis mellifera colonies in UK.
abstract: The reproductive behaviour of female Varroa destructor mites invading worker brood cells during the winter months (January to mid-March) was investigated in four Apis mellifera colonies in UK. The number of viable offspring produced during a reproductive cycle, per mite, was only 0.5 during winter compared with 1.0 during the summer. This was mainly due to a large increase in the population of non-reproductive mites (winter 20%, summer 8%). This increase can be explained by the high level of male offspring mortality observed in winter (42% vs. 18% in summer), which results in nearly half of the newly reared female mites being unfertilised. Since mites that do reproduce lay a similar number of eggs in winter (X = 4.7) as in summer (X = 4.9), and the level of mortality suffered by the first female offspring is similar in winter (7%) as in summer (6%), it is probably not the internal physiological state of the host which causes the high level of winter non-reproduction, as has been previously suspected.
authors.affiliation: Department of Animal and Plant Sciences, Sheffield University, Western Bank, UK. S.J.Martin@Sheffield.ac.uk
authors.forename: S J
authors.initials: SJ
authors.lastname: Martin
mesh_terms: D000818:Animals; D001516:Bees / Q000254:growth & development / Q000469:parasitology*; D005260:Female; D008297:Male; D008925:Mites / Q000254:growth & development*; D012098:Reproduction; D012621:Seasons; D006113:United Kingdom