having a whale of a time! Humpback Whale

Noongar word - Mammang

Hear all about it!

Humpback Whales are a migratory species. Their feeding grounds are near the Antarctic and they spend the summer months there. They feed on swarms of krill (small prawn-like creature about 4 cm long) and can eat up to two tonnes a day! They build up a thick layer of fat reserves called blubber. This layer is rich in oil and was the reason why whales were hunted from the seventeenth century until commercial whaling was banned in 1986.

Humpback whales tend to feed alone. Humpbacks use their huge mouths to capture krill swarms in the seawater. They filter the seawater out leaving their food behind. Humpbacks use ‘bubble feeding’ to bring the krill swarms together making them easier to catch. They blow lots of bubbles in a ring under the krill swarms forcing them together and trapping them inside the ring. They then swim up through this ring with their mouth open. Sometimes a group will work together to do this.

Every year, these whales form groups and migrate north to the warmer winter breeding grounds closer to the Equator like the Great Barrier Reef. Mothers and their claves will swim very close to each other on this journey. The whales will feed a little along the way on zooplankton but feeding is not their focus.

Humpback Whales are powerful swimmers, sometimes they will breach. This is when they throw themselves out of the water, roll in the air and crash back down. Scientists do not know why they do this. Another mystery is the songs that these whales sing. These can last for hours and the sounds can travel huge distances through the water.

Threats include; climate change affecting their migration routes, breeding and feeding sites and food supply. Pollution, stranding, predation by Orcas on calves, illegal whaling, noise pollution (noise of ships, seismic surveying), injury from shipping.

Where you can find a Humpback Whale

Conservation Status

Listed as Least Concern under ICUN (2014). The waters around Rottnest Island are a designated Marine Reserve. All cetaceans are protected within the Australian Whale Sanctuary under the EPBC Act. The Sanctuary includes all Commonwealth waters from the three nautical mile State waters limit out to the boundary of the Exclusive Economic Zone (out to 200 nm and further in some places). The EPBC Act also classifies Humpback Whales as Vulnerable.
  • Extinct
  • Extinct in Wild
  • Critically Endangered
  • Endangered
  • Vulnerable
  • Near Threatened
  • Least Concerned

Help protect Rottnest's marine environment

  • Do Not approach whales when boating
  • Do enjoy watching them on their own terms
  • Do take litter with you or use bins provided
  • Do collect fishing line if seen in ocean or on shores