title: High Varroa mite abundance influences chemical profiles of worker bees and mite-host preferences.
abstract: Honeybee disappearance is one of the major environmental and economic challenges this century has to face. The ecto-parasitic mite Varroa destructor represents one of the main causes of the worldwide beehive losses. Although halting mite transmission among beehives is of primary importance to save honeybee colonies from further decline, the natural route used by mites to abandon a collapsing colony has not been extensively investigated so far. Here, we explored whether, with increasing mite abundance within the colony, mites change their behaviour to maximize the chances of leaving a highly infested colony. We show that, at low mite abundance, mites remain within the colony and promote their reproduction by riding nurses that they distinguish from foragers by different chemical cuticular signatures. When mite abundance increases, the chemical profile of nurses and foragers tends to overlap, promoting mite departure from exploited colonies by riding pollen foragers.
authors.affiliation: Dipartimento di Biologia, Università degli Studi di Firenze, via Madonna del Piano, 6-50019 Sesto Fiorentino (Florence), Italy rita.cervo@unifi.it.
authors.forename: R
authors.initials: R
authors.lastname: Cervo
authors.affiliation: Dipartimento di Biologia, Università degli Studi di Firenze, via Madonna del Piano, 6-50019 Sesto Fiorentino (Florence), Italy CISM, Centro di Servizi di Spettrometria di Massa, Università degli Studi di Firenze, Viale Pieraccini, 6-50139 Florence, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Bruschini
authors.affiliation: Dipartimento di Biologia, Università degli Studi di Firenze, via Madonna del Piano, 6-50019 Sesto Fiorentino (Florence), Italy.
authors.forename: F
authors.initials: F
authors.lastname: Cappa
authors.affiliation: Dipartimento di Biologia, Università degli Studi di Firenze, via Madonna del Piano, 6-50019 Sesto Fiorentino (Florence), Italy.
authors.forename: S
authors.initials: S
authors.lastname: Meconcelli
authors.affiliation: CISM, Centro di Servizi di Spettrometria di Massa, Università degli Studi di Firenze, Viale Pieraccini, 6-50139 Florence, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Pieraccini
authors.affiliation: ARPAT, Associazione Regionale Produttori Apistici Toscani, Via Finlandia, 20-50126 Florence, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Pradella
authors.affiliation: Dipartimento di Biologia, Università degli Studi di Firenze, via Madonna del Piano, 6-50019 Sesto Fiorentino (Florence), Italy CISM, Centro di Servizi di Spettrometria di Massa, Università degli Studi di Firenze, Viale Pieraccini, 6-50139 Florence, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Turillazzi
mesh_terms: D063147:Animal Distribution / Q000502:physiology*; D000818:Animals; D001516:Bees / Q000737:chemistry / Q000469:parasitology*; D001522:Behavior, Animal; D006790:Host-Parasite Interactions; D034582:Integumentary System / Q000502:physiology; D057077:Varroidae / Q000502:physiology*
keywords: Apis mellifera; Cuticular hydrocarbons; Mite abundance; Parasite transmission; Varroa destructor