Humpback Whales Make a Comeback in Australia

humpback whale

Story at-a-glance -

  • From the early 1900s to the 1970s, Australian humpback whales were hunted and killed, pushing them near extinction
  • As of 2012, humpback whale populations had grown to more than 63 percent (east coast) and 90 percent (west coast) of their pre-whaling era populations
  • Humpback whales are currently listed as a threatened species in Australia, but due to their recent resurgence researchers have suggested removing their vulnerable status

By Dr. Becker

Baleen whales, such as gray whales, blue whales, and humpback whales, are known as the "great whales," and they fit researchers' "hypothetical most endangered animal" description precisely. Animals at risk of endangerment or extinction often fit the following characteristics:1

Large in size Long lifespans
Late reproductive age Few offspring
Commercial value Distributions that cross international boundaries
Behaviors that place them at risk from a number of anthropogenic (related to humans) activities  

Many marine mammals fit this description, and humpback whales are no exception. From the early 1900s to the 1970s, the whales were also commercially harvested off the coast of Australia, to the extent that tens of thousands of the majestic creatures were killed, pushing them near extinction.

Threatened Humpback Whales Make a Major Comeback

Humpback whales are currently listed as a threatened species (vulnerable status) as well as a migratory species in Australia, both of which are identified by the Environment Protection and Biodiversity Conservation Act of 1999 (EPBC) as a Matter of National Environmental Significance (MNES).

This means any activity that takes place within Australian waters and may impact a humpback whale must only be done with government approval and a special permit. The protection proved to be a success.

As of 2012, data suggests humpback whale populations had grown to more than 63 percent (east coast) and 90 percent (west coast) of their pre-whaling era populations. Their numbers are now so high that a whale-watching industry has sprung up. According to a report published in Marine Policy:2

"Optimism and hope in conservation biology are supported by examples of endangered species recovery, such as the population growth observed in humpback whales in several of the world's oceans.

In Australia, monitoring data suggest rapid recovery for both east and west coast populations, which are now larger than 50 percent of their pre-whaling abundance. The measured growth rates exceed known species trends worldwide and have no indication of diminishing."

On the contrary, numbers of Australian humpback whales are increasing at a rate of 9 to 10 percent a year.

Should Humpback Whales No Longer Be Listed as Threatened?

The comeback of humpback whales is being touted as a great conservation success, one that may act as a "symbol of hope and optimism for marine conservation." The Marine Policy report suggests that since the whales are no longer at risk of extinction they be delisted as a threatened species in Australia.

This, the report noted, would allow conservation funding to be directed toward other species that are more at risk, such as blue whales and, possibly, Australian snubfin and humpback dolphins. Humpback whales' conservation status has also been downgraded in other regions, including off British Columbia, Canada.

Delisting the humpbacks presents challenges of its own, of course, as it leaves the whales more vulnerable to human exploitation or harm. Marine scientist and study author Michelle Bejder told Discovery News:3

"Increased interactions with maritime users are likely to occur…' [including acoustic disturbance from noise, collisions with vessels, entanglements in fishing gear, and more interactions with the booming whale watching industry.]

'Adaptive management actions and new approaches to gain public support will be vital to maintain the growth and recovery of Australian humpback whales and prevent future population declines.'"

Although the Australian humpback whales' comeback is a success story, other whale species haven't been so lucky. Sadly, seven of the 13 great whale species are now classified as endangered or vulnerable, despite many years of protections.4

Fascinating Humpback Whale Facts

Humpback whales have long been given the title of longest-migrating mammal, as they travel up to 10,190 miles round trip from the cold waters near Antarctica to the warm, tropical waters of the Pacific. However, this distinction was recently handed over to the gray whale, which was found to travel nearly 14,000 miles round trip.

Still, humpback whales display other impressive feats, like learning to imitate group behaviors. Humpbacks not only learn songs from one another, but they also learn and imitate hunting behaviors of those in their social circle. They've also been caught on camera showing joy and appreciation after being rescued from fishing nets.

Perhaps this isn't entirely surprising, since mother humpbacks and their young are known to swim close together, touching, in what appears to be a show of affection.5 Perhaps most intriguing of all are the humpback whales' magical songs. As National Geographic reported:6

"Humpback whales are known for their magical songs, which travel for great distances through the world's oceans. These sequences of moans, howls, cries, and other noises are quite complex and often continue for hours on end.

Scientists are studying these sounds to decipher their meaning. It is most likely that humpbacks sing to communicate with others and to attract potential mates."

Male humpback whales also "sing" songs that are unique to the region they live in. Males will sing the same 10- to 20-minute song over and over for hours at a time, possibly as part of mating behavior.

Also intriguing is the fact that every humpback whale has a unique shape and color pattern to its dorsal fin and flukes (tail), which is now used by researchers as a method of identifying individual whales (like a human fingerprint).7

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