A team of scientists discover a new behaviour displayed by Pilot Whales in Canada. Just like babysitting in humans, alloparental care is the care of a young animal by another adult that is not its parent, known as the alloparent. The phenomenon is common in many social animals, even fish, but this is the first study identifying it in Pilot Whales.
Alloparental care can be direct or indirect with alloparent’s being fathers, siblings, or even unrelated individuals. Indirect behaviours increase another parent’s juvenile survival without necessarily being directed at them.
Some birds are known to be marvellous indirect alloparents. The Acorn Woodpecker have large family units where nests are built and maintained for future generations by older siblings, cousins and even friends.
A parent directly helps a juvenile that is not its own through interactions like grooming and providing food, a behaviour often displayed by Eastern Bluebirds , the state bird of New York and Missouri.
Babysitting is an example of direct care, where the carer will change its behaviour in order to be close to the young so as to benefit its survival. Meerkats often babysit pups in their natal burrow, allowing the mothers to forage for food. Meerkats are dedicated babysitters, often losing 2% of body weight from reduced foraging, to ensure the pups are kept safe.
There are various reasons why alloparental care has evolved in different species; in order to increase the chance their genes will pass onto the next generation through advertising their mating quality, increase their parental experience or in order to stay within a well-functioning group of individuals, in the same way we pay rent to our landlords. Benefits of staying within a group include increased safety from predators, food supply and access to mates.
A new discovery, published in Nature this month, displays pilot whales regularly taking part in direct alloparental care.
Whale-watching boats in Cape Breton, Nova Scotia, have been observing Pilot whales since 1998, giving the researchers, led by Augusto Joana from the Dalhousie University in Halifax, Canada, a huge data set to play with. Various techniques were used to identify calves and mothers including photo-identification; a technique that can identify individual’s markings, tooth rakes, white scars, pigmentation patterns and dorsal fin shapes. Further data was collected using foam-tipped darts and crossbows to collect DNA samples of the population of whales, to confirm their sex.
In this population of Pilot Whales, alloparental care was observed in all stages of the calves’ development. It was calculated that in some years alloparenting was observed in over 85% of calves including parent females and males, which puzzled the team of scientists.
Augusto explains why male pilot whales take part in alloparental care.
“It’s a way to advertise that they’re a good mate, basically”
Augusto noticed that when pilot whale calves are with other members of the group, the baby-sitters rarely alter their behaviour. Why was this?
“The calf might be learning from experiences with different individuals of how they should be behaving socially,” Augusto says.
Other species of whales and dolphins participate in baby-sitting including beluga whales, sperm whales, orcas and bottlenose dolphins. For example, sperm whales babysit calves through altering their dive synchrony to look after the calf nearer the surface and belugas even give other parent’s calves their milk. It is thought that the behaviour is a by-product of these species social structure and has a very small cost to the fitness of the alloparent’s involved, allowing the behaviour to be common amongst cetaceans.
Even interspecies caring can occur in cetaceans. See a humpback whale look after a deformed dolphin in the video below. The reason this happened is probably because the dolphin couldn’t keep up with its pod so it stayed with the whale for safety.
Find out more about our Whale and Dolphin Conservation Project in Tenerife where Pilot Whales are in abundance and you can observe these and other cetaceans to aid in the scientific understanding of these majestic animals by collecting important scientific data
By Meike Simms - Online Media Intern