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Pilot whale families "babysit" each other's young

- January 19, 2017

Pilot whales in Pleasant Bay, Nova Scotia. (Joana Augusto photo)
Pilot whales in Pleasant Bay, Nova Scotia. (Joana Augusto photo)

Each summer, a group of marine biologists packs their bags and treks out to the shores of Cape Breton, N.S. with a mission to conduct fieldwork aboard whale-watching vessels.

As they coast along the temperate North Atlantic waters, these researchers are hard at work gathering photographic data and documenting the interactions between some of the more than 3,000 long-finned pilot whales that call the region home during the summer.

It turns out the pilot whale population is not so different from human beings when it comes to raising children. The research team discovered that babysitting, or alloparental care, of babies by other adult whales is an integral part of this species social structure.

Heading this longitudinal research study was Dal Biology PhD student Joana Augusto, whose final thesis dives further into the topic of social patterns and organization within the pilot whale population and investigates how other factors such as genetics play an influencing role in sociality.

Augusto worked alongside , professor in Dals Department of Biology, and Timothy Frasier, associate professor in the Department of Biology at Saint Marys University, on the care study, which has its roots in the broader pilot whale-watching project that began in 1998.

Augusto joined Dr. Whiteheads field research team in 2009. They partnered with a Cape Breton whale-watching company and travelled out on the water up to five times daily for several hours each excursion in summer months.

Seeking safety and prestige


An unexpected yet intriguing finding emerged as Augusto combed through her gathered data. Whereas alloparental care is predominantly provided by female adults in the majority of marine mammal species, it was observed that in the case of pilot whales, many males from different family units adopted the role of babysitting the young instead.

[This was] one of the coolest things I found, says Augusto, who attributes the active involvement of male pilot whales in alloparental care to two possible constructs.

One is the concept of social prestige, which explains that the male whales act the way they do to boast about their own fitness or abilities. In essence, they are broadcasting or advertising that they are doing so well for themselves that they can afford to spare some of their time and energy to take care of another.

The more likely explanation to account for the overarching occurrence of babysitting in this interactive whale species, however, is that the cost of fulfilling this role is swimmingly low when considering the caregivers fitness. Limited resources and efforts are required from the alloparent but advantageous and significant results are yielded when we ponder the thought that baby whales wandering the open seas are safer from predators when simply accompanied by an adult.

An added benefit, Augusto says, is that they [the calves] might be learning social behaviours and how to behave in their group not just from their mother, but from the other individuals surrounding [and spending time with] them.

Because the overall benefits of this type of care appear to outweigh any negative impacts on the adults partaking in alloparenting, it makes sense that babysitting has seemingly become an innate component of long-finned pilot whales social lives and development.

For more information, the full research publication, Characterizing alloparental care in the pilot whale (Globicephala melas) population that summers off Cape Breton, Nova Scotia, Canada by Augusto, Whitehead, & Frasier (2016), can be found in the Marine Mammal Science journal, DOI: 10.1111/mms.12377