It’s that time of year again when the humpback whales take their long migration journey (up to 10,000km in fact!) from the Antarctic seas to the subtropical waters and back again. Their journey north seemed to start late this year, and perhaps it did. The timing of the humpback migration can vary from year to year depending on a whole variety of factors, including water temperature.
One big nomadic breeding cycle
During the southern summers humpback whales spend their time in the Antarctic waters feeding on krill. As the weather cools they begin their migration north for winter.
One of the reasons for the journey to warmer tropical waters is to mate. After the mating season, newly pregnant females return to Antarctica to spend another summer feeding and building up reserves to make the long journey north again to birth. Little newborn humpback calves have very little body fat and wouldn’t survive in the icy waters of the Antarctic, so pregnant females travel to the warmer tropical waters for birthing.
It would seem then that every second year a female is either mating or birthing. Pregnancy lasts 11-12 months, as does nursing so a mature female humpback can birth a calf every 2 years.
Mothers nurse their calves for up to a year, which includes the first journey north after the calf’s birth. Mums and bubs stay close to each other during the first year of life, keeping eyeball to eyeball contact and touching fins often. By the time the humpbacks have reached their warmer mating and birthing grounds, the calf is almost a year and ready to become independent. They will most likely stay close to their mothers until they make their second trip south to Antarctica however.
It takes much longer than a year for the calf to reach full adulthood though. They’re considered immature until about 5 years old and they keep growing until they’re 10 years old. They can live for 45 – 50 years, which means if they do the migration each year they could potentially travel 500,000km in their lifetime!
Did you know that humpbacks have a traveling formation?
The nomadic migration is not merely random. It has an order to it.
The first humpbacks to head north towards the warmer winter grounds are mums with their young calves. They’re followed about 2 weeks later by the immature males and females and mature males set off later again. Pregnant females tail the pack and are the last to leave the feeding ground. On the return journey south back to the Antarctic feeding grounds the humpbacks travel in the same order.
Many groups of humpback whales travel north from the Antarctic to various warmer waters in the southern hemisphere. Some groups diverge and take different routes. For those that diverge further south of the east coast of Australia, Cape Byron is the point where then converge again, making it one of the best spots in Australia to sight whales.
Some viewing spots
There are a few ideal spots to whale watch from land in and around Byron Bay.
- Cape Byron Lighthouse
- Broken Head viewing platform
- Pat Morton Lookout area at Lennox Head
- Ballina Head Lookout
- Norries Head at Cabarita Beach
- Fingal Head
The Wild About Whales website shows a map of the latest whale sightings along the NSW coast. They also have a smartphone app that allows you to find the top whale watching spots in NSW and record your own whale sightings.
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Featured photo credit: Jodie Lowe via Instragram
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For details on the best walks and viewing places on the Byron, Tweed and Ballina coast order the Byron Trails guidebook.
