Robert Prettejohn, the owner of Thala Beach Nature Reserve was fortunate to experience an extraordinary humpback whale encounter in the Coral Sea near Port Douglas.
A humpback ‘family’ was sighted near Snapper Island, with a female humpback seemingly showing a young calf how to breach. While a male kept paternal watch over his family, other humpbacks kept their distance.
Whale song is a form of communication by humpback whales, a vocalisation which is often inaudible to human ears. To record their communication is a rare opportunity indeed. Marine mammals such as these humpback whales rely on vocal communication, much more so than their other senses of sight and smell.
Humpback whale recording on the Great Barrier Reef near Port Douglas, Queensland Australia
Whale song is a whale’s way of communicating with the pod
According to the Department of Environment and Energy whale songs consist of distinct sequences of groans, moans, roars, sighs and high pitched squeals that may last up to 10 minutes or longer. It is thought these sounds could be used for communicative purposes such as to identify other individuals, for long-range contact and to warn others of threats as well as navigation. Baleen whales do not have vocal chords so scientists are still unsure how whale songs are produced.
Toothed whales and dolphins (for example killer whales and bottle-nose dolphins) use echolocation for hunting and navigating, while baleen whales (for example humpbacks and blue whales) generally produce a series of sounds which are frequently termed ‘songs’ that are used for communicating.
Toothed whales (including dolphins) have developed a remarkable sensory ability used for locating food and for navigation underwater called echolocation. Toothed whales produce a variety of sounds by moving air between air-spaces or sinuses in the head. Sounds are reflected or echoed back from objects, and these are thought to be received by an oil filled channel in the lower jaw and conducted to the middle ear of the animal.
When swimming normally, the sounds emitted are generally low frequency; the echoes from these sounds provide information about the seafloor, the shorelines, underwater obstacles, water depth, and the presence of other animals underwater. A recent theory suggests that very high intensity focused sounds may be used to stun or disorient prey in hunting.
Echolocation is extremely sensitive and some scientists think it may provide toothed whales and dolphins with a three dimensional view of the world. The whistles, clicks, groans and other noises made by many toothed whales are also thought to be also important in communication between individuals.
Humpback whales on the Great Barrier Reef
Humpback whales migrate north from southern waters each year, generally between May and September. If you’re taking a cruise to the Great Barrier Reef during this time keep an eye out for these magnificent mammals!