In the southern winter, whales from the Antarctic journey north past New Zealand and into Australia's northern coastal waters. Come spring they return to the Antarctic.
Sometimes they can even be spotted before the year's whale migration season officially begins, and you could see whales frolicling in Sydney Harbour and along the coast, sometimes as early as May.
Whales have been visiting the harbour for years during the whale migration season with hundreds more taking the route to warmer waters farther offshore.
And there are eyes at the ready to spot the all-white humpback whale, Migaloo, who has been visiting Australian waters almost yearly.
There have been instances when southern right whales frolicked in the harbour within a stone's throw of the Sydney Opera House.
At one time, a female southern right whale stayed in and around Sydney Harbour for 21 days.
In June 2005, a pod of false killer whales beached themselves in Western Australia not far from the town of Busselton.
Volunteers quickly headed for the beach to rescue the stranded whales.
One of the dolphin-sized mammals died, but rescuers refloated 74 others and the whales were last seen swimming out to sea.
While the southern right whales appear to be the more unconcerned about proximity to people and even nearby boats, it seems it is the humpback whale which is the more quickly found in the waters of Australia, and New Zealand, during the whale season.
This whale season coincides with winter and spring (June to November) when the humpbacks migrate north from the Antarctic to warmer Australian waters and then head south again.
The northern migration follows routes around New Zealand and up the coast of Australia, in the east to the Great Barrier Reef and in the west to areas around and north of Shark Bay and Ningaloo Reef in Western Australia.
A foremost whale watching outpost in New Zealand is the town of Kaikoura in the South Island where, in fact, whale watching is a year-round affair as different species of whale frequent its waters at different times of the year.
In Australia, the northern migratory route of the humpback whale is farther offshore than its southern route, so while whales may be spotted from land on their journey north, the chances of seeing them are higher on their return trip to the Antarctic.
Popular spots for whale watching are, on the Australian east coast, Hervey Bay and Stradbroke Island in Queensland, Cape Byron and the Sapphire Coast in New South Wales, Point Hicks in Victoria, and Storm Bay in Tasmania.
On the southern and western coasts, the Ottway Coast in Victoria, the cliffs of the Great Australian Bight, and Cape Leeuwin, Shark Bay and Ningaloo in Western Australia are favorite whale watching spots.