Whales may be intelligent, but they're not human – so don't expect them to behave in a human-like way when they're entangled in ropes, lobster pots or buoys, says a visiting expert.
Whale entanglement authority Bob Bowman, who works for the non-profit Provincetown Centre for Coastal Studies in Cape Cod, Massachusetts, was speaking at a two-day workshop in the city last week.
Participants focused on safe and efficient disentanglement of whales and the scientific monitoring of the problem in South African waters.
With the continuing rapid increase in the population of southern right whales visiting our waters each year, entanglement in the many thousands of pots laid by the rock lobster industry is predicted to grow.
This has led to the recent establishment of the South African whale disentanglement network, which has as members the Marine and Coastal Management branch of the Department of Environmental Affairs, the Fish Hoek-based Dolphin Action Group, the Sharks Board, the NSRI, the SAPS diving unit, border police, Pretoria University's mammal research unit and the Table Mountain National Park.
The rock lobster industry has also been drawn in, and it sponsored Bowman's visit to Cape Town.
Bowman's group has been working on the problem since the mid-1970s and has an international reputation.
Bowman said whales most prone to entanglement in South African waters were southern rights and humpbacks.
"I think a lot of the general public who haven't had first-hand experience with them think of whales as really big people – they're not.
"We know they're intelligent, but that intelligence doesn't translate into anything that we can understand – whales don't necessarily react the way people would to the same stimuli.
"So for us, interpreting what a whale does is difficult."
Bowman has developed a series of specialised tools for the job that, ironically, are partly derived from the tools used by early whalers, including hooked knives on the end of long poles.
He said dealing with entanglement was potentially "a very dangerous business" and there had been some "close calls" with his team.
"Because you're working alongside a massive animal – they are just so big that all it takes is for an animal to flinch or to give a little flick and it's all over."
The key was to "control" the whale, which could involve a "sleigh ride" of up to two hours being towed behind it, he said.
Bowman said they managed to free 52% of the entangled right whales they were called to, and had a much higher success rate with humpbacks, at nearly 90%.