There is nothing more majestic than seeing the biggest animal on earth breaching the surface of the water in an incredible demonstration of strength, skill and size. Whale watching isn't in the Sydney stereotype, but the harbour town sits right on a migration root for a few species of whale. Humpbacks and Southern Right Whales are the most common but if you beat the odds, you may be lucky enough to see something a little more unusual. Don't get your hopes up; it only happens once in a Blue Whale.
Trips with Prestige Harbour Cruises are relatively cheap. Most leave from Darling Harbour and take a few hours. I'd advise to go in the morning. Not only are you more likely to see a whale, but the light from the morning sun gives you a chance for the perfect photo. Through June to July many Humpback whales are migrating north to have their calves. It makes winter a great time to try and spot the illusive creatures. They begin to head back to colder waters from the end of September all the way through until December. It is possible to see one all year round, but you'll dramatically increase your chances if you go during these times.
I went in the winter months. It was fantastic. We did see whales, albeit from a distance. Lucky they're big. The main attraction, however, hadn't been mentioned all day. The oceanic bottlenose dolphin was an impressive surprise. Growing up to a few meters long, their size coupled with their agility makes them an exciting animal to watch. Their playful personality and inspiring intelligence allow them to come right up to the boat, gliding along in its wake. It's a photographers dream.
I wasn't lucky enough to see a whale breach, but the experience was definitely worth it. However, if you're looking for the best whale show, I'd say head up north. Not to Manly, I'm talking Queensland North. It's where they're all heading. Rather than chancing them as they migrate, you can watch them while their safe, still and rearing their young.