Foraging Activity inPlebeia remota, a Stingless Bees Species, Is Influenced by the Reproductive State of a Colony

Abstract

Colonies of the Brazilian stingless bee Plebeia remota show a reproductive diapause in autumn and winter. Therefore, they present two distinct reproductive states, during which colony needs are putatively different. Consequently, foraging should be adapted to the different needs. We recorded the foraging activity of two colonies for 30 days in both phases. Indeed, it presented different patterns during the two phases. In the reproductive diapause, the resource predominantly collected by the foragers was nectar. The majority of the bees were nectar foragers, and the peak of collecting activity occurred around noon. Instead, in the reproductive phase, the predominantly collected resource was pollen, and the peak of activity occurred around 10:00 am. Although the majority of the foragers were not specialized in this phase, there were a larger number of pollen foragers compared to the phase of reproductive diapause. The temperature and relative humidity also influenced the foraging activity.

Survival strategies of stingless bees (Melipona subnitida) in an unpredictable environment, the Brazilian tropical dry forest

“…Pollen foraging activity directly influences the amount of pollen available within the nests of highly eusocial bees, which is primarily used for brood rearing (Roubik 1982;McNally 1992a, 1994). Thus, in line with similar findings for other stingless bee species (Roubik 1982;Ribeiro et al 2003;Nunes-Silva et al 2010a) and for honey bees (Seeley 1985;Schneider and McNally 1992b), M. subnitida down-regulated its brood production in periods of food scarcity and concomitant decline in pollen collection (Figure 3). Owing to the reduced rearing of new brood, the populations of bee colonies decrease over time (Free and Racey 1968).…”

“…Owing to the reduced rearing of new brood, the populations of bee colonies decrease over time (Free and Racey 1968). This, together with the reduced activity of the remaining adults, results in a diminished consumption of the stored food reserves, which are fundamental for the colonies to quickly restart their activity (foraging and brood production) as soon as forage availability begins to increase (McNally and Schneider 1992;Ribeiro et al 2003;Nunes-Silva et al 2010a).…”

Diapause in Stingless Bees (Hymenoptera: Apidae)

“…In preparation for these cold winters, the construction rate of brood cells falls gradually until it stops entirely. Consequently, the queen's egg-laying is interrupted in many Plebeia colonies during the milder autumn months of March to May (Juliani, 1967;Terada et al, 1975;Imperatriz-Fonseca & Oliveira, 1976;Kleinert-Giovannini, 1982;Wittmann, 1989;van Benthem et al, 1995;Pick & Blochtein, 2002b;Ribeiro et al, 2003;Alves et al, 2009;Nunes-Silva et al, 2010). This kind of diapause in stingless bees has been called reproductive diapause (Juliani, 1967;Terada et al, 1975;van Benthem et al, 1995;Pick & Blochtein, 2002b;Ribeiro et al, 2003;Alves et al, 2009;Nunes-Silva et al, 2010).…”

“…Many workers and the queen can be seen clustered in specific regions of the nest, under or over food pots or among the pillars (or lamellae), where they exhibit lethargic movements or remain completely immobile (Ribeiro et al, 2003). These "winter workers" are longer lived than the workers emerging at other times (Table 1) (Blochtein et al, 2008;Nunes-Silva et al, 2010).…”

“…However, little is known about this phenomenon in stingless bees, although it is possible that glycogen and body fat reserves also significantly decrease during this period. Reproductive diapause in stingless bees has been recorded as lasting from 2 up to 6 months (Juliani, 1967;van Benthem et al, 1995;Pick & Blochtein, 2002b;Ribeiro et al, 2003;Alves et al, 2009;Nunes-Silva et al, 2010) (Table 1). However, colonies inhabiting the same locality may not always commence their reproductive diapause in synchrony (Juliani, 1967; van Ben- , 1995;Pick & Blochtein, 2002b;Ribeiro et al, 2003;Alves et al, 2009;Nunes-Silva et al, 2010).…”