Humpback whales find an abundance of their main food supply near the Arctic Circle and Antarctica, but every year they start their annual migration from their food supply to warmer waters. Why such a long migration? The answer is quite simple.
The females must give birth to their calves in warm waters, because the calves are born without the layer of blubber, and could not survive in the icy waters of polar region.
There are some eighteen separate migration routes for Humpback whales around the world, and here in Hervey Bay, we are lucky to be near one of them, from Antarctica to the Great Barrier Reef, a return trip of some 10.000km! These whales eventually come into the waters of Hervey Bay, but only on the return trip from the Reef (although some of us are starting to question this).
Why do the whales come into Hervey Bay? This had the scientists puzzled for some time, but the answer seems fairly simple: R and R, or rest and recreation. The females bring their four to six weeks old calves into the Bay, where they have no fear of killer whale or pack-shark attack, where mums can recover after the stresses of calving and feed their young the enormous amount of milk they require to gain weight and the layer of blubber, vital to their survival in the icy waters of Antarctica. The following year the female and the now developed yearling again call into the Bay, before going South, where junior has to learn how and what to eat and to survive without the constant attention of mum. Sounds familiar? It appears that adults continue their stop-over in the Bay, which now emerges as a regular cycle: August mainly adults, September adults, juveniles and mothers and calves and October mainly mothers and calves, sometimes in company of an "escort", another adult. And they stay only for an average 2 to 5 days, some longer, some whales don't. But during the 1993 whale watch season a number of tour operators reported that they identified whales that were sighted very early in August and again sighted much later in the season! Does this mean that some Humpbacks call into Hervey Bay twice during their migration, once going North and again on the way South?
The now famous white whale was sighted on the 29th August near Bikini Cliffs and again sighted towards the end of September off Moreton Island. Where did it go during that month? It only takes two or three days for whales to travel from Hervey Bay to the East coast of Moreton Island.
It is encouraging to know, that there is an annual increase of 13.5% reported since 1990, but the Humpbacks are still the third most endangered species of all the big whales.
