SYDNEY (Reuters) - Australian scientists are using military technology for locating submarines to track rare blue whales hundreds of kilometers away by eavesdropping on their distinctive songs. Blue whales can communicate with each other over an entire ocean basin by emitting low frequency sounds, or deep songs. Scientists from the Australian Antarctic Division started using directional sonobuoys this year to detect whale sounds -- a big improvement on the standard visual method of monitoring whales. "Ultimately we're trying to get an abundance estimate for blue whales. ...