For several years, scientists have suspected that orcas have been killing and eating parts of great white sharks. Now, they have video evidence to prove it.
New drone and helicopter footage show a pod of orcas ruthlessly pursuing a great white shark in Mossel Bay, South Africa for more than an hour before going in for the kill. The video culminates with one of the killer whales gobbling up a large chunk of the shark's liver.
A scuba diver in British Columbia, Canada, has been fined a record 12,000 Canadian dollars ($9,250) for approaching a pod of orcas too closely.
In British Columbia, vessels must keep at least 200 meters away from orcas and in southern B.C. coastal waters between Campbell River and just north of Ucluelet, vessels must keep 400 meters away. Vessels must be at least 100 meters away from all other cetaceans.
In the pre-drone days, researchers relied on their observations of the orcas when they surfaced, and this was understandably limited.
“Until now, research on killer whale social networks has relied on seeing the whales when they surface, and recording which whales are together," said lead author Michael Weiss, of the University of Exeter.
"Looking down into the water from a drone allowed us to see details such as contact between individual whales," he added.
Focusing on nine of the most commonly found dolphin, whale and porpoise species in UK waters, the strategy has been developed by the Scottish Government, in collaboration with the UK Government, the Welsh Government and the Northern Ireland Executive.
Its objective is to ensure the effective management to achieve and maintain the current favourable status of the nine species. It highlights certain pressures where further research or extra management measures may help to improve the conservation of marine mammals.
Equipped with an autonomous hydrophone, the buoy's function is to conduct for the first time real-time acoustic monitoring of the water's cetaceans to assess how oceanic noise pollution affects them.
Deployed as part of the Smart Whale Sounds project, it will also track the distribution and behaviour of whale species in real-time and be used to train machine learning models to identify different species' calls.
This scenario may one day become reality. And to be efficient, such robots would need to be maneuverable and stealthy, and be able to closely mimic the movements of the marine creatures.
Scientists like Keith W. Moored are working on the next generation of underwater robots by studying the movements of dolphins and whales. "We're studying how these animals are designed and what's beneficial about that design in terms of their swimming performance, or the fluid mechanics of how they swim."
Whether or not you have watched (or agree with) the movies Free Willy or Blackfish, the predicament of captive cetaceans is one that can spark off a heated debate from both sides of the fence.
Nonetheless, such movies and increased awareness have led to public calls for attractions and venues that keep wild animals captive to release them.
Marine-animal attractions like SeaWorld are particularly under fire due to their animal shows featuring captive cetaceans trained to perform for public entertainment.
In a study involving 378 orcas (or killer whales), researchers observed the first non-human example of the "grandmother effect" in a menopausal species.
This is when post-reproductive grandmothers (in this case, orcas) assist other members of the species with their offspring, thereby improving the young ones’ chances of survival. It was found that these post-reproductive orcas had the largest beneficial impact on their grandoffspring’s survival chances.
Regarded as one of the ocean's most formidable predators, killer whales are pack hunters, with some orcas hunting other marine mammals while others prefer to eat only fish. In a new study published in the Journal of Experimental Biology, Matthew Bowers from Duke University and colleagues speculated whether aquatic mammals that are potential killer whale prey could distinguish calls of the predatory killers from those of other marine mammals.
Regarded as one of the ocean's most formidable predators, killer whales are pack hunters, with some orcas hunting other marine mammals while others prefer to eat only fish. In a new study published in Journal of Experimental Biology, Matthew Bowers from Duke University and colleagues speculated whether aquatic mammals that are potential killer whale prey could distinguish calls of the predatory killers from those of other marine mammals.
