Footage of dolphin's 'savage' behavior towards fish leaves onlookers worried
PERTH, AUSTRALIA: One Perth resident was out for a stroll on the afternoon of March 27 when he witnessed a dolphin repeatedly knocking a fish out of the ocean. Although it is well known that a pod of resident dolphins lives in the Swan River and that the group was recently connected to a fatal shark attack last month, locals rarely observe one acting in this manner.
The walker acted quickly to record the behavior, which he called "savage," on video before posting it online. "It doesn't happen everyday but it's pretty common for dolphins to play with things in the water," said Jeff Weir, executive director at the Dolphin Research Institute.
READ MORE
Adam Walker: Swimmer saved by ‘hero’ dolphins that scared off deadly shark about to attack him
'Cat and mouse' hunting strategy
Weir told Yahoo News Australia that there were three possible explanations for why the highly intelligent creature would choose to behave in this manner. According to Weir, mother dolphins frequently use this "cat and mouse" strategy to teach their young about hunting. The motivations can vary from educational to "aggressive" behavior.
Orca mothers, another species of the Cetacea family, which also include dolphins, have been seen using this tactic in the wilds as well. Fish are thought to pose a lower risk of injury than other prey, according to researchers in New Zealand, so moms of orcas choose them as prey when they teach their young how to hunt for food.
Dolphins love to 'play' with their food
However, Weir dismissed the "educational hunt" possibility as the most likely explanation for the Swan River dolphin's behaviour. While "practice" hunting is a common educational activity, the animals in the video seem to be the same size — so they were likely same age peers rather than a mother dolphin with her young ones.
Another explanation is that the dolphin, unable to bite their prey into bite-sized pieces, acted in this manner in an effort to break the "big fish" into smaller "bite-sized" parts. Dolphins are known to throw larger animals out of the water in an effort to tear them apart before consuming the fragmented parts whole without "cutting or chewing" with their teeth.
Eating a live octopus can be deadly, even for a #dolphin. To ensure the octopus is dead and unable to attach its tentacle to its throat, the dolphin will repeatedly toss the octopus in the air until to head pops off. pic.twitter.com/JPoH4rXcdD
— Daniel Schneider (@BiologistDan) November 26, 2017
"That's a pretty big fish and it might be a bit big for them to swallow, so they could have been doing that," Weir shared. "They often bang squid and jellyfish in the hopes of eating them".
The last alternative is that the dolphin could have just been toying with the fish because it could. "Just like humans they can be nasty and really aggressive," Weir shared. High-IQ dolphins have been known to exhibit sinister behaviors, whether they are starving and trying to secure their next food or just passing the time.