Parrots that dunk their food reveal that humans are not the only ones who prefer soggy snacks.
Not only humans, but also some cockatoos have been found to enjoy a wet treat by dunking their food before consuming it, according to researchers.
The team observed that captive Goffin’s cockatoos were dipping their food during lunch, similar to how some individuals dip cookies in their tea. Intrigued, they decided to investigate further.
In a study published in Biology Letters, scientists from the University of Vienna detail how they provided food for birds by putting twice-baked bread (also known as rusk), dried fruit, seeds, and bird pellets in bowls within their aviary. Tubs of water were also present during the food placement.
During a 12-day period, the team documented the birds that dipped, the item they dipped, the duration of the dip, and if they ate it afterwards.
In general, the group observed that 7 out of the 18 cockatoos dipped their food into water at least once. The most commonly dunked item was rusk. Two of the birds who dipped their food the most seemed to prefer eating wet rusk. While dried banana chips and dried coconut chips were also sometimes dipped in water, these two birds tended to prefer them dry.
The researchers noted that the behavior appeared to primarily focus on rusk, a type of dry and sturdy food that readily absorbs water and becomes soft and damp in texture.
The scientists discovered that the seven cockatoos had varying amounts of time in which they left their rusk pieces in the water. Some of them allowed the core to soften, as noted in the team’s own experiments with rusk-dunking.
The team stated that the absence of live prey makes it impossible for the birds to be attempting to drown their food. Additionally, the presence of easily accessible water makes it unlikely that they were submerging their food in order to obtain fluid.
The researchers note that the birds’ seasoning behavior is unlikely, as they dip their food in plain tap water. Additionally, the fact that the birds are selective about which foods they dunk suggests that they are not attempting to clean their food.
Consequently, the team suggests that the birds most likely dipped the rusks in order to moisten them, a tactic that could potentially enhance their texture.
The scientists suggest that the birds’ actions demonstrate the ability to control impulses and delay gratification, showcasing their resourcefulness in the context of food preparation.
The authors state that since only certain individuals have been seen dunking food and it has not been witnessed in the wild, they consider this to be a natural foraging discovery by one or more individuals.
Simon Reader, a professor at McGill University in Montreal, expressed surprise that parrots had not been studied for their dunking behavior, despite his own previous research on dunking by wild Carib grackle birds. He was not involved in the current study.
According to the speaker, dunking is not a common behavior among wild Carib grackles. However, it was not as unique as previously believed as nearly all birds were capable of doing it under ideal circumstances. These circumstances include having access to dry food and water, and being in a safe environment where their food cannot be stolen.
Similar to these parrots, dunking appears to be a behavior they utilize based on the potential advantages and disadvantages in the moment.