Academic Review 2024

15 ACADEMIC REVIEW 2024

“ ...they will zero in on one fish, and they will follow that single fish until they catch it. ”

HUNTING In this section I will analyse the differing hunting methods of both O. orca and T. truncatus . These hunting techniques are evidence of the intelligence acquired by these cetaceans. Each technique connects to the particular scenario at hand. When these cetaceans adapt to their environment, they can thrive to an exceptional extent. When both these odontocetes hunt a shoal of fish using echolocation, Dave Anderson, the captain of Dave’s Dolphin & Whale Watching Safari, explains ‘they will zero in on one fish, and they will follow that single fish until they catch it’ (Illustra Media, 2016). 1. Slap and stun: Killer whales use their tails to slap fish on the edge of a baitball, or shoal of fish, effectively paralysing them. When stunned the fish are left floating, as an easy pick for the killer whales, who therefore conserve energy as no chasing is involved. They seem to curl their tails inwards at either end, increasing the streamline speed of the strike. Sometimes the momentum of the slap causes them to spin 360° before they feast on their victims (Learning from Whales, 2016). 2. A life-threatening wave: Killer whales of the Antarctic have been filmed coordinating very sophisticated attacks. A pod of orcas spotted a lone crabeater seal on a small ice sheet. Four orcas from the pod lined up, side by side and swam in synchrony straight towards the ice sheet with the seal on top. Once they reached it, they quickly submerged creating a huge wave, pushing the seal into the sea on the other side where another orca was waiting for the kill (Lindblad Expeditions-National Geographic, 2018). HUNTING TECHNIQUES OF ORCANUS ORCA :

HUNTING TECHNIQUES OF TURSIOPS TRUNCATUS :

1. Mud cages: Pods of T. truncatus in the shallow estuary off the coast of Florida catch fish in the most bizarre, cooperative fashion. Once a school of fish has been located, one of the dolphins is assigned the job known as the chaser, circling their prey while slapping their tail flukes against the seabed. This disturbs the silt creating an artificial wall, or net. The other members of the pod scare the fish inwards, enclosing them in this circle. Out of distress the fish jump out the water over the mud cage to escape, however the rest of the pod are waiting for them. It is so effective that the fish jump straight into their mouths (BBC, 2015). 2. Stranded: A different population of common bottlenose dolphins hunt at low tide by the mudbanks of Orlando and South Carolina. Working together, they use the mudbanks to corner their prey. Forcing the fish and themselves onto the banks with a wave of water, both species become beached. The dolphins risk their lives to get these meals. They all beach with their right side facing on the mud, this stops the fish from retreating back into the water (BBC Earth, 2018). The sources I have used are dependable, as the footage is either from wildlife studies or broadcast television documentaries, showing real footage of these attacks in the wild. The hunting strategies differ between species due to their contrasting environments. Different populations adopt different techniques because of the particular habitats which they live in, which is proof of their intelligence.