Whales (Humpback)
Knowing the basic statistics about a humpback whale does little to prepare you for the surprise and awe of seeing a 16 metre, 45 tonne mammal all but completely lift itself out of the water then crash back into the sea sending spray several metres into the air.
When a whale surfaces, the simple act of exhaling results in a ‘blow’ of spray and air that shoots up to 4 metres in the air as it empties 90% of the contents of its lungs in less than a second. The whale’s lung capacity is about the same volume as a small car.
Then, when it breathes in and dives, it can stay submerged for around 10-15 minutes on a typical dive and up to about 30 minutes on longer dives.
| Size | Usually up to 16m (females are slightly bigger) |
|---|---|
| Weight | 30–45t |
| Fluke width | Up to 4m |
| Pectoral fin length | Up to 5m (about a third of the total body length) |
| Brain size | 5kg (60cm circumference by 22cm long) |
| Heart | 1.2–1.5m long |
| Aorta | 60cm diameter |
| Blood volume | 10–15% of body weight (up to 6.5t of blood) |
| Intestines | 60m long |
| Skull | 2–5m long by up to 2m wide |
| Food consumption | Up to 2,000kg/day when feeding |
| Life expectancy | Up to 80-90 years |
| Gestation period | 11–12 months; calving interval usually 2-3 years. |
| Size of calf (at birth) | 4–5m |
| Breeding age | Usually 5–10 years |
| Migration | 9,000km (round trip) |
| Speed | Generally 3.5–5.0 knots or 6.5–9.2km/h (fastest speed 9–10 knots or 18.5km/h) |
| Population size | Approximately 12,000 in 2008 (increasing by around 10% each year). Current estimate 50,000 eastern Australian humpacks. |
White whales
At least 3-4 white whales are migrating along the east coast of Australia; sightings are rare and not guaranteed each season. Migaloo and Bahloo, Willow and Migaloo Jrn (although it is unknown if he is related to Migaloo) have been seen in Queensland waters. Unlike Migaloo, these other predominantly white whales have some black markings on their body, leading researchers to believe they have a condition called leucism, or hypo-pigmentation.
In Queensland, whales that are totally white or predominantly white (more than 90%) can be declared ‘whales of special interest’. This gives these whales extra protection from being disturbed, by increasing the distance that boats and other watercraft must keep from them. For Migaloo and other special interest white whales vessels must keep at least 500m away.
Migaloo
Migaloo is a white humpback whale that was first seen in 1991 off Byron Bay. At the time it was believed to be 3–5 years old. Queensland tourism notes the last reported sighting was in 2020 off Port Macquarie, NSW.
In 1998 and 2003 it was recorded singing, indicating that Migaloo is a male. This was confirmed in 2004 when tissue samples from Migaloo were analysed.
In August 2003 when he was 15–17 years, he was hit by a sailboat off Townsville. He now has a scar arcing diagonally across the left side of his back, halfway between his blowhole and dorsal fin.
Bahloo
In July 2008 another white whale was seen in Queensland waters. This one, named Bahloo after an Aboriginal moon spirit, was first seen swimming off the Gold Coast. Little is known about Bahloo other than that it has a few black spots on its head and tail.
Protecting whales and dolphins
Whales or dolphins may be declared as being a ‘special marine mammal' if they are at risk of harassment, injury or being killed.
Special interest whales and dolphins include animals that are colour-variants (e.g. totally white whales), young separated from their mothers, or individuals that are in a place that is readily accessible to the public.
Areas of special management
Marine mammal special management areas can also be declared to provide additional protection for whales and dolphins within a specified area, such as important mating, calving, resting or migratory habitats.
Within these areas, or for special marine mammals declared under legislation, increased approach distances and other management measures may apply to minimise human disturbance. Examples include white whales and whale calves in the Great Barrier Reef marine Park.
Whale strandings
If you encounter sick, injured or even dead whales report it by using the free QWildlife app for iOS and Andriod, or call 1300 130 372 (Press option 1). A Queensland Government officer or trained strandings responder in the relevant region will be contacted with the details of your sightings and will determine the appropriate response.