5.4. Cultural control

An alternate, environmentally safe control is to use a ‘grease’ patty. More accurately, this is a vegetable shortening and sugar patty (2:1 sugar: shortening by volume, or sufficient shortening that the mixture does not break apart).  Vegetable shortening (solid, hydrogenated vegetable oil, not animal fat) and white granulated sugar will keep mite prevalence to 10%, well below typical economic thresholds (<20%). Animal fat will go rancid over time and is not recommended.  Liquid vegetable oil can be used, but the patty will be looser and may not hold up in the hive, unless mixed with ample amount of sugar.

A 113 g patty, placed on the top bars at the centre of the broodnest where it comes in contact with the most bees, will protect young bees (which are most at risk) from becoming infested. Patties can be prepared ahead of time if they are wrapped in waxed paper and stored in the freezer. The shortening appears to disrupt the questing female mites as they search for new hosts (young bees) (Sammataro and Needham, 1996; Sammataro et al., 1994). Because young bees are emerging continuously, the patty must be present for an extended period. The optimal application seasons are fall and early spring, when mite levels are increasing.

Requeening colonies is likely to alter HBTM infestations once offspring of the new queens begin to emerge; those new offspring may be more or less resistant to mites than the worker offspring of the original queens. Apiary location may also affect tracheal mite infestations (vanEngelsdorp and Otis, 2001a; L de Guzman, unpubl. data), perhaps due to temperature or humidity effects. Harbo (1993) demonstrated that hives exposed to the sun in Louisiana had reduced mite infestations.  Integrated Pest Management (IPM) techniques have been successful in keeping HBTM under control; however, no biological controls currently exist (Fig. 14).

A cautionary note should be added. Many non-commercial beekeepers are opting not to treat for mites or diseases, allowing survivor stock to become established.  HBTM may reappear if treatments for varroa mites are suspended; sampling for HBTM is therefore recommended, especially if colony symptoms consistent with tracheal mite infestations are observed.

Fig. 14. Integrated Pest Management (IPM) tactics for bee mites. For HBTM, ‘grease’ patty should be listed with essential oils and powdered sugar (D Sammataro).