Just absorb this (thanks to the Living on Earth podcast for this short segment):
…Experts estimate there are about 40,000 humpbacks that migrate each year between the southern oceans around Antarctica and the oceans around Australia. And there used to be 1500 a half century ago, mostly wiped out due to wailing.
BASCOMB: Wow, that’s an amazing recovery though 1500 to 40,000 in just 50 years. How do they do it?
DYKSTRA: No whaling is a big help. Whaling was banned in Australia in 1978. The fleet’s from the former Soviet Union and Japan that used to go down to the Antarctic, no longer touch humpback whales. Japan is the only nation that goes down there at all. And humpbacks have been completely protected from hunting. Their food source is mainly krill, those tiny little crustaceans, and although krill are under some threat from fishing, in the southern oceans around Antarctica, humpbacks have still been able to get their fill of krill. And so they’re doing well…
Listen to the segment here.