A mega-pod of more than 100 humpback whales have been spotted in a feeding frenzy off the NSW south coast.The aquatic mammals often pass through Bermagui with their young on their long journey back to Antarctica from the warmer northern waters. The whales were seen working together to catch a large school of bait fish. It's only the second time the spectacle has been caught on film - after a mega-pod was witnessed feeding at the same spot last year.