Southwest Atlantic humpbacks return from the brink

One of the whale populations taken to the edge of extinction by commercial hunting in the early 20th Century has essentially recovered its numbers.

It's estimated the humpbacks that frequent the southwest Atlantic once totalled perhaps 27,000 animals. This group was reduced to only a few hundred by the steam-driven boats and harpoons operating out of the British Overseas Territory of South Georgia.

But as Dr Jennifer Jackson, from the British Antarctic Survey tells our science correspondent Jonathan Amos, these humpbacks have now largely re-established themselves.