Learned foraging preferences after experiencing adulterated pollen in honeybee colonies.

LAJAD, ROCÍO; ARENAS A

Encuentro; III Reunión de Biología del Comportamiento del Cono Sur 2021 (Brasil).; 2021

The mechanism by which honeybees Apis mellifera select pollen is little understood. Pollen, the main protein resource of bee colonies, may vary in its composition according to the floral origin. Worker bees of different ages use pollen in various ways. Fresh pollen is not ingested by foragers at the source and it has been suggested that they are not able to make foraging decisions based on pollen composition. We hypothesize that pollen assessment occurs after pollen is processed inside the nest, likely mediated by young bees that consume pollen. To unveil the mechanisms by which foragers avoid less suitable pollens, we performed dual-choice experiments with colonies confined in flying cages (9x3x2m). We compared foragers' preferences for two monofloral-pollen sources after one of them was adulterated with a deterrent (amygdalin). The adulterated pollen was offered either: i) to foragers at the pollen source; ii) to all the bees inside the hive; or iii) to young bees transiently isolated from the colony. Differences in pollen preferences were analyzed by means of linear regression with normal distribution in the R environment. We included controls where pollen was offered unadulterated. Interestingly, our results indicate that: (i) when the adulterated pollen was experienced directly at the food source, foragers did not avoid it (P>0.05); (ii) but they did after pollen had been offered adulterated inside the hive compared with the control (P0.05). Altogether, results suggest that assessment of pollen composition requires the resource to be experienced inside the hive for honeybee foragers to adjust their preferences to the most suitable pollens.