The humpback whales never miss a migration cycle. Whale watchers witness this every year on the east coast of Australia. To start from the beginning, Australian humpback whales spend the entire summer feeding on small fish and krill in Antarctica. According to marine biologists, the whales start their migration, 10,000-11,000 km towards the north, around the month of June.
Younger male whales lead the procession, while the mothers and calves follow behind as they are the last ones to arrive in the northern waters of the east coast. This is because migration allows whales to be in more subtropical weather where they can mate. Remember that summers around the world, between May, June and July, are winters in Australia. Every year, whales travel here to give birth to calves too.
The humpback whale goes as far towards the northern area as the Coral Sea and Cairns. Whale watchers talk of frequent sightings near the Whitsunday Islands, the Moretan Bay, and Hervey Bay. The thriving whale watching industry has developed for 18 years now, thanks to these whale migrations. The female whales, in particular, make use of the protected bays to stop, feed their calves, and fatten them up before they have to head to Antarctica, which is freezing. The whales also migrate to bays along Pittwater Bay, Sydney Harbour, and New South Wales. They then commence their trip back south in late July and August, with most whales leaving the Queensland area in the middle of November. This migration is never easy; therefore, only the whales and calves which are in healthy condition are able to make the journey. On top of that, the trip is not easy as there are predators on the lookout for these beasts as they serve as their food source.
The truth is that the whales are not safe wherever they are. They make the trip along the east coast to escape the frozen waters of Antarctica in winters and even there, Japanese whalers have set-up camp for hunting whales. The other dangers to a humpback whale are the Orcas. Orcas are known to prefer eating the tongues of whales. Drag marks of the Orca are seen on the tails of many whales that make it through their migration. But, that is not all; sharks are known as predators of whales too. The Great Whites migrate the same time whales do, by following groups of whales and looking for their weakest link which would make for an easy prey.
Tiger sharks are commonly found in tropical waters. A number of these usually bite the whale so that as its swims and bleeds, more sharks start arriving to attack it. However, Orcas are not that common here. A humpback whale might also be struck by ships while migrating. Whales usually get tangled in fishing gear or get stuck in the cray pot ropes. The ships’ propellers may even scratch the skin of a whale.