A Window into the Lives of Resident Killer Whales
- Articles, Blog

A Window into the Lives of Resident Killer Whales

Killer whales are big, intelligent animals
at the top of their food chain. They’re found in all of the world’s oceans
and live for decades in groups, passing down knowledge and culture
from one generation to the next. But their days here in British Columbian
waters might be numbered. Endangered by many threats to their safety and their
food supply, some of the killer whales here are at risk of being lost for good. So a team of researchers is on the hunt
for clues, information that could lead to solutions that just might help
these killer whales survive. Three genetically distinct groups are
found here in the northeast Pacific Ocean. The offshore killer whales—they’re rarely
spotted and we know very little about them. The transients, or Bigg’s, killer whales,
who mainly eat marine mammals and travel through the waters of
southern California up to Alaska. And the resident killer whales, fish eaters
broken into northern and southern populations. Water and noise pollution, increased shipping
traffic, and a shrinking food supply have impacted killer whales here, and now most
of these groups are listed as threatened. With fewer than 75 individuals left,
the southern residents—classified as endangered—are especially at risk. But to help the killer whales survive, we
need to know more about them. Which is why the Marine Mammal Research Unit at the
University of British Columbia, together with the Hakai Institute, recently spent
three weeks on the water trying to learn as much as possible about
resident killer whales. They’re hoping to find out more about
what they eat and how they hunt. The team filmed killer whales using
drones, which allowed them to record undisturbed behaviour of the
animals in their natural setting. They also attached GPS, depth, and speed
recording tags that had cameras and hydrophones to gather information
from individuals. The team used hydroacoustics to gather
information about the number of fish available to killer whales in
the area, and their depth. And finally, they collected environmental
data, including salinity and temperature, from the surrounding waters. It will take months to analyze all
of this data, but here’s a sneak peak at what the team saw out on the water. Residents use a series of whistles, calls
and clicks to communicate with each other, and many of these noises
are unique to each pod. Killer whales use echolocation—sounds that
travel through the water and bounce back, exposing their prey in coordinated
group hunts, and they often share with each other the food they catch. Known to eat fish, squid, turtles,
seabirds, seals, penguins, whales, and even sharks, killer whales around
the world have a fierce reputation. And this blue shark kept its distance. But these resident killer whales
mainly eat chinook salmon, which might help explain
their low numbers. Salmon populations have dropped
dramatically in recent decades, and the resident killer whales might be
having a hard time finding enough to eat. Killer whales start having babies when
they’re around 15 years old. They typically have one baby at a time
every three to five years. Recently though, only a few resident
killer whales calves have been born, and many of those aren’t surviving. Hopefully, the efforts of this trip will
give us new insights into killer whales and how to help them survive
well into the future.

About Gregory Ralls

Read All Posts By Gregory Ralls

Leave a Reply

Your email address will not be published. Required fields are marked *