Footage reveals little-known ‘surfing’ whales in Australian waters

Drone image of Bryde’s whale (Balaenoptera edeni) behind the surf break at K’gari, Fraser Island, Queensland.
Image credit: T. Arnell and A. Ihle (@TakeThe MAP)

As humpback and southern right whales return to Antarctica at the end of their annual migration, East Coast whale watchers might think the show is soon over. But some species of whales are always present, perhaps all year round. And we need to know more about them.

My team’s new research focuses on one of these little-known species: the Bryde’s whale (Balaenoptera edeni). You may have seen it feeding, drilling or surfing, without knowing what it was.

My colleagues and I wanted to learn more about where Bryde’s whales are found in Australian waters. We therefore exploited observations shared on social networks, including drone images and photographs of whale watching excursions. We also collected observations from scientists.

We discovered a wealth of information. It includes evidence of feeding and “surfing” behaviors that may never have been documented before. The results of this research will directly help inform conservation efforts to protect this species, about which we still know so little in Australian waters.

Watching whales using citizen science

Scientists cannot always be in the field or on the water. This is why data collected by ordinary people, called “citizen scientists,” can be so useful. It captures valuable information about wildlife that can later be used by professional researchers.

Citizen science projects involving marine life have grown in recent years. These include people documenting humpback whale recovery by counting humpback whales migrating north off the coast of Sydney, and people observing sharks off Bondi Beach via @DroneSharkApp.

Hungry, hungry whales

Like humpback whales, these giants are “baleen” whales, meaning they are toothless. But Bryde’s whales have a much more pointed mouth and do not have that famous hump.

A preference for warmer waters means Bryde’s whales are also known as tropical whales. They are found in tropical or subtropical waters.

Around the world, Bryde’s whales have demonstrated interesting feeding behaviors, ranging from high-speed chases across the seafloor to “pirouettes.”

Hanging out in shallow and deep water

Our study documented Bryde’s whales feeding in deep and shallow waters off the east coast of Australia, alone or sometimes with other whales.

We leveraged over an hour of drone vision and over 200 photos of Bryde’s whales shared by citizen scientists on social media platforms such as Facebook, Instagram and YouTube.

In offshore environments, Bryde’s whales were typically observed “lateral lunging,” meaning they propelled themselves forward and turned sideways, then opened their mouths to engulf their food. They also swam from below and collected their prey, much like humpback whales.

In shallow water, Bryde’s whales have been observed feeding directly in or behind the surf break.

We believe this is a new feeding behavior for this species. We call this “shallow water surffeeding”.

Perhaps the whales use the waves to aid their feeding efforts, or perhaps they are there because that’s where the baitfish hang out.

Regardless, it’s impressive to see such a big whale in the waves and shallow waters:

Spotted: mothers with their calves

We have also documented mothers with calves. This indicates that parts of Australia’s east coast could potentially be an important area for nursing mothers with their young. They could also use these waters for birthing.

We do not yet fully understand the species’ movements in Australia and whether they swim in New Zealand waters. For example, the world-famous white humpback whale, Migaloo, swims across the Tasman Sea.

Could these Bryde’s whales we see here in Australian waters be the same ones seen in New Zealand waters? Do they calve in New Zealand or Australia and move between the two? If so, what does this mean for their protection?

Whales do not recognize international borders. They go where they want, when they want. This is why collaborative research like this is important to our growing knowledge of this species.

The more we know, the better we can protect ourselves

This is the first paper to focus on both the presence and feeding behavior of Bryde’s whales in Australian waters.

As humans continue to expand their footprint in the ocean through activities such as offshore wind power, shipping, fishing and tourism, knowledge of this and other species can help inform future decisions in our blue backyard.

The results of this study will directly contribute to Australia’s efforts to protect whales. An immediate step will be to provide information to the federal review of biological areas important for protected marine species. The more we know, the better we can target conservation efforts to protect a species we know relatively little about in Australian waters.

And even as humpback and southern right whales head south to Antarctica for the summer, it’s still worth keeping your eyes peeled for the water. You might be the next person to spot a Bryde’s whale in Australian waters. Let us know if you do!

Vanessa Pirotta, Postdoctoral Researcher and Wildlife Scientist, Macquarie University

This article is republished from The Conversation under a Creative Commons license. Read the original article.