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Varroa mites are highly attracted to drone brood of honey bees (Apis mellifera), as it increases their chance of successful reproduction. Therefore, drone brood removal with trap frames is common practice among beekeepers in Europe and part of sustainable varroa control. However, it is considered labour‐intensive, and there are doubts about the effectiveness of this measure. At present, it is mostly unknown how many mites a drone frame can carry at different times of the season, and how many mites can be removed on average if this measure is performed frequently. Therefore, we sampled a total of 262 drone frames with varying proportion of capped cells (5–100%) from 18 different apiaries. Mites were washed out from brood collected from mid‐April to mid‐July based on a standard method to obtain comparable results. We found that a drone frame carried a median of 71.5 mites, and with the removal of four trap frames, about 286 mites can be removed per colony and season. In addition, mite counts were significantly higher in June and July than in April and May (Tukey‐HSD, P < 0.05). The number of mites and the proportion of capped cells, however, were not correlated (R2 < 0.01, P < 0.05). Our results suggest that drone brood removal is effective in reducing Varroa destructor numbers in colonies, supporting the findings of previous studies on the efficacy of this measure. Although mite counts varied, we believe that increasing sample size over different seasons and locations could elucidate infestation patterns in drone brood and ultimately improve drone brood removal as an integrated pest management tool for a wider audience of beekeepers.

Étude du spectre des sucres du miellat de Buchneria pectinatae (Nordl.) par chromatographîe en phase gazeuse et par analyse enzymatique Gerhard LIEBIG L üll Jt S t 1 ! b I Jl i. / ii.°r B ienen k u l /dc f J u h cJihcu J/ Puufach 106, D 1000 Slullgarl 70 (B.R.n.) SUMMARY Y GAS CHROMATOGRAPHIC AND ENZYlv1ATlC EXAMINATION OF HONEYDEW OF THE APHID 8UCHNERIA PEC11NA TAEBNÖRDL) l!i i977 and 1978 honeydew of Buclzueriu pe;-tinacae which teed on ,4ba! alha was colicutcct " '° i,u !ubar composition was analysed. Sucrose, melezitose and fructose, the major components of fio!!e),Oew are averaging 60, 20 and 10% respectively. Trehalose, maltose and glucose are present in levels less than 5 %. Galactosc is not foun,1 T n c portions of sugars found in honeydew vary within a little range. These vacations are ncither Cd' i dated with changes in the density of aphid populations nor with the CI ' weathci or scasonal fact"rs concerning the vegetation. When the density of population of B. 1 ;ectiiiatue decrejscd there is no variation in the composiUd" m 'Sugars !.; Hoiteyde'A coiicCted by night contains more sucrose and less meteLitosc than hoiicy.JeD< coiiecteu oy ,-1?;.41ght. ZUSAMMENFASSUNG Wahren d der l'anninirächt ] '-)7 und i 978 wurde an verschiedenen Standorten Honig!au aufgefangen auf sein Zuckerspektrum analysiert. Saccharose. Nlelezitose und Fructose niachen etwa 90 'io dcr Zu_ k er aus; das Vcitiältriis von Saccharose zu Melezitosc zu Fructose liegt im Durchschnitt bei 6.!:) I Trehatüse, Nialtcse und Glucose treten ebenfalls reg!lmässig. aber nui in grrwgen Mengen aut. Ga!a;;tuse

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