Allonursing in captive belugas (Delphinapterus leucas)

Area of Science:

• Marine Mammal Behavior
• Cetacean Biology
• Reproductive Strategies

Background:

• Alloparental care, the nursing of non-offspring, is observed across mammalian taxa.
• Belugas (Delphinapterus leucas) exhibit complex social behaviors.
• Understanding nursing behaviors is crucial for cetacean conservation.

Purpose of the Study:

• To document and describe allonursing behavior in captive belugas (Delphinapterus leucas).
• To investigate the extent and duration of allonursing in this species.
• To infer the potential occurrence of allonursing in wild beluga populations.

Main Methods:

• Observation of a male beluga calf at the Vancouver Aquarium Marine Science Center.
• Monitoring nursing interactions with the calf's mother and two additional non-pregnant, non-lactating females.
• Recording the duration and frequency of allonursing events over 34 months.

Main Results:

• Two adult female belugas, unrelated to the calf, spontaneously lactated and nursed the calf.
• Allonursing occurred intermittently over a 34-month period.
• The calf was nursed by its mother and these two allonursing females.

Conclusions:

• Allonursing is a documented behavior in captive belugas (Delphinapterus leucas).
• These findings suggest that allonursing may also occur in wild beluga populations.
• Alloparental care, including allonursing, may provide evolutionary benefits for calf protection in belugas.