Australian wildlife authorities and scientists in the Top End are pondering how to get a giant humpback whale – and possible three whales – out of a river in Kakadu National Park and back out to sea.
Among the ideas are using whale calls to lure it in the right direction – a strategy that has apparently been successful used elsewhere – and creating underwater noise pollution to drive the animal away from the upstream part of the East Alligator River.
There are also hopes that a very high tide due in a few weeks may help take the whale, or whales, back out the mouth and into the Timor Sea.
Pod of three whales spotted early September
A pod of three humpback whales was spotted in the river on 2 September by a local marine expert, but authorities have since lost track of two of them and hope they have already made their way out.
However, the East Alligator River is murky and it is possible that they’re simply not being seen. “It’s so murky you can’t see them until they’re up out of the water,” ecologist Jason Fowler said.
The wayward whales have attracted public attention from around the world and authorities in the Northern Territory say they are “stunned” by the sightings, as there have never been any previous reports of humpback whales venturing into a river in the territory.
One NT newspaper, the Katherine Times, has labelled it a ‘once in a lifetime’ event.
This is not an emergency situation as yet
The lone known whale is said not to be in distress, so authorities are not viewing it as an emergency situation at the moment and hope to tag the whale shortly so as to better monitor its movements before deciding on a plan of action.
Meanwhile park rangers have set up an exclusion zone to prevent boaters in the river coming into contact with the animal. Any collision, they warn, would likely have disastrous consequences for the boat.
They are also not concerned about the strong presence of crocodiles. “[A whale] is not something a crocodile would even be capable of attacking. It’s just way out of a crocodile’s world,” said Dr Carol Palmer of the Northern Territory Department of Environment and Natural Resources.