What’s the only non-human animal capable of giving a killer whale a fright? Pilot whales! A thread 
Killer whale-pilot whale interactions have been documented in Iceland, Norway, Spain, and there are anecdotal reports from Western Australia. The Selbmann et al. (2022) paper gives great insight into these interactions in Iceland
Anna Selbmann@annaselbmann
Jun 10 22
View on Twitter
Our new paper on occurrence of pilot whales and killer whales in Icelandic coastal waters and their interspecific interactions is out now in Acta Ethologica and it’s open access! rdcu.be/cPnCi
Below is a short thread summarising the main results.
Here is a short video showing one of the interactions
Anna Selbmann@annaselbmann
Jun 10 22
View on Twitter
Interactions common when both species sighted simultaneously. Pilot whales move towards killer whales, who show avoidance response (moving away, minor evasive behaviours) in 68% of interactions but high-speed avoidance (porpoising) observed in 28%. 
Rebecca Bakker
Rebecca Bakker When I was doing field research in Norway, a massive pod of pilot whales showed up one morning. I missed out on the sighting, but all of the killer whales in the area vanished. The pilots were gone by the following morning, and the killer whales started coming back.
In Western Australia, the southern subspecies of long-finned pilot whale has reportedly been seen charging and chasing killer whales there
m.facebook.com/story.php?stor
It’s not currently known why pilot whales display this antagonistic behavior. While killer whales do occasionally prey on pilot whales, it is not common, particularly amongst the fish-eating killer whales they are known to harass in Norway and Iceland.
Regardless, it may be an anti-predator mobbing behavior. Basically, a pilot whale’s way of saying “Hey, I see you! Get out of here!”
Why do the killer whales run away from the pilot whales? The triggers for this fleeing behavior are not yet known. Are there acoustic cues? Does the size of the pilot whale pod vs killer whale pod matter?
To add to the mystery, last year, researchers in Iceland documented a newborn pilot whale traveling with a pod of killer whales, with no other pilot whales in sight. Are they calf-napping?!
Icelandic Orca Project@icelandic_orcas
Jun 24 22
View on Twitter
BREAKING: ORCAS AND A BABY PILOT WHALE 
Yesterday our team found a group of playful #orcas and to our absolute astonishment amongst the orcas was a newborn pilot whale. There were no observations of pilot whales in the area the whole day. Where did this baby come from?
Yesterday our team found a group of playful #orcas and to our absolute astonishment amongst the orcas was a newborn pilot whale. There were no observations of pilot whales in the area the whole day. Where did this baby come from? 
There’s still many things to be learned about these interactions. References below!
Emma Luck
@emmaluck22
BSc in marine biology from @uasoutheast. Wildlife photographer and naturalist specializing in marine mammals 🐋 🦦 let’s talk about whales
Missing some tweets in this thread? Or failed to load images or videos? You can try to .