The first call was from Bex Russell, who saw a 1.7 meter bronze whaler shark (Carcharhinus brachyurus) stranded on the mudflats near Millionaire's mile.
The animal was calm and sedate, probably suffering from lack of oxygen and exposure.
It was refloated by Dr Simon Elwen of the Namibian Dolphin Project and within a few minutes swam away into deeper water.
Just over an hour later, there was a report of another shark stranded in a similar position. This animal was slightly smaller, and again calm and refloated easily.
Within the next hour, 2 more sharks (one more bronze whaler and one smooth hound shark) were found by local residents, all successfully refloated and we are hopeful that they made it back out into open water.
We are not sure why they stranded, but it most likely due to the warm temperatures and a lack of oxygen in the water associated with the current sulphur bloom.
While the sharks we have encountered so far are quite placid, bronze whaler sharks can and do bite and wild animals are unpredictable and potentially dangerous especially when stressed.
The Namibian Dolphin Project is a research and conservation project working in Walvis Bay and Lüderitz, Namibia. The goals of the project are to gather data on the abundance, distribution and habitat use of whales and dolphins in Namibia.
This project is working with Oceans Research and is funded by grants from several organisations. We work closely with the Namibian Ministry of Fisheries and are hosted within Namibia by the Namibia Nature Foundation. The Project team currently consists of Simon El-wen, Tess Gridley, Heidi Etter and Ruth Leeney.
Some important things to bear in mind with stranded whales and dolphins:
- Most of the time, animals strand due to natural causes such as disease, injury or old age (which aren't always obvious) and refloating them isn't likely to prolong their lives anyway.
-These animals can (and increasingly do) carry diseases that can infect people. People also can transfer diseases to animals.
- Cetaceans are large and extremely strong, even the smallest local animal (the Heaviside's dolphin) weighs about 50-60kg and adult humpback or right whale weighs 10s of tons. Throw in some heavy seas and big swells and you have a recipe for disaster. Sixty kg's being thrown into you by the force of some pounding swells will knock you over at the very least, or a larger animal could very easily roll onto your foot and trap you underneath it. Don't forget that a whale's tail can push it's entire body out of the water when breaching - if it hits a person with that tail while on the beach...
- With respect to the situation of a large animal such as this in big surf - refloated animals often just turn immediately once in the water and swim along shore and then straight back on to land.
Bear in mind that these animals have likely never lain on the ground before (and thus experienced gra-vity as us land mammals do) and this can result in squashed or even crushed internal organs in larger animals (especially their lungs), upset balance and one would image, just general disorientation.
Sperm whales are fairly tall and narrow in shape, so tend to lie on their side when stranded, which makes it even harder to move them and probably disorients them even more than other animals.
To reduce this disorientation and reduce the risk of restranding, the approach advised by experienced people is to, once back in the water, hold the animal upright at the surface for several minutes up to half an hour to allow it to reorient itself and get its breathing back to normal.
Unfortunately, there is no logistical way that a handful of people could get an adult sperm whale 16m long, which weighs in the range of 20-30 TONS and has been lying on its side on the beach for at least 5 or 6 hours, out through that surf zone and then hold it upright in the water while it gets used to floating again.
The best equivalent I can think of is if some-one held you upside down by your ankles for 6 hours then turned you upright and told you to immediately run across a busy highway in a straight line, you'd need a little help and time to get used to being upright again.
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