Last of the Humpback Migration for 2020Friday, 22nd January 2021
By Lloyd Edwards
The below video was of the last time we saw a pod of 20 plus humpback whale males passing Algoa Bay. It was taken using a mobile phone on a Raggy Charters Bird Island cruise by Robyn Dougans, who does marketing for Amakhala Game Reserve. We were stationary at the time the whales approached us, which is in line with our whale watching permit guidelines. Normally you need to keep a distance of 50 metres, unless the whales approach you, which, as can be seen, was the case here. This is the largest group of humpback males that I have ever seen at once and it was quite scary! They simply have no fear and swim straight towards the boat and veer off at the last moment.
So if the last of the Humpbacks passed Algoa Bay at the beginning of December, why have I kept this video until now? The reason is as follows. For the last 23 years Raggy Charters has been monitoring the whales passing Algoa Bay. Up until five years ago they started coming past us at the beginning of June on their Northern migration and again until the middle of January on their Southern migration. So what has caused them to shorten the migration by six weeks in 2020?
Top cetacean scientists including Dr. Simon Elwin concur that the main reason is because of the changing marine environment. Climate change and global warming definitely have an impact on the distribution of the whale’s food, mainly krill and copepods. In scientific terms this is known as “nutritional stress”. We also know that after nearly being wiped out by 1960, Humpback whales are now nearing their pre exploitation carrying capacity. Although it is not known for sure, the carrying capacity is probably a lot less today than before whaling commenced. When all the large whales were nearly wiped out by the whalers, this had a huge impact on the recycling of nutrients and other food related issues. A case in point was in 2017 when around 20 humpback juveniles stranded between Mossel Bay and Namibia, also food related.
On the positive side, we have seen rapid increase in the large whale populations which is good news indeed. We need to stand together, form networks and educate people in case human related activities reverse this trend.