Hump back whale breaches
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Migrating whale numbers hit 50-year high

15 November 2011 Last updated at 04:54 GMT

There has been a rise in the number of migrating whales. They travel on a 5,000km (3,100 miles) round trip to give birth off the coast of Australia before heading back to Antarctica to their main feeding grounds.

It is the highest number seen in half a century.

Duncan Kennedy reports from Sydney.