It’s just the kind of quirky story from the animal kingdom that grabs everyone’s attention. A new documentary series by BBC One called "Dolphins - Spy in the Pod" allegedly contains footage of dolphins getting "high" on the toxin produced by puffer fish. A video clip of the behaviour released as a teaser has been generating lots of buzz and discussion all week … and it’s not hard to understand why: who doesn’t want to watch the world’s favourite cetaceans "passing the puffer" around to get stoned?! 

The series producer, zoologist Rob Pilley, told The Sunday Times that the dolphins "are purposely experimenting with something we know to be intoxicating" and entering a “trance-like state”. 

“After chewing the puffer gently and passing it around, they began acting most peculiarly, hanging around with their noses at the surface as if fascinated by their own reflection,” he said.

Watch:

But is getting stoned really what's going on here? The series episode in which the puffer fish sequence appears (revealingly called "Pass the Puffer") airs later today, but some experts have been weighing in on the issue in the meantime. 

We got in touch with science researcher and dolphin blogger Justin Gregg, who’s posted on the stoned-dolphins controversy here. First off, he notes that the dolphins’ "stoned" appearance in the clip is quite possibly the result of the animals squinting due to bright light. As for the their apparent fascination with their own reflection after chewing on the puffer, Gregg says:

If they are looking at their reflections (which is impossible to say from the footage), it would not be anything out of the ordinary. As dolphin cognition researcher Diana Reiss pointed out, “I can tell you that when they’re not intoxicated, they are also fascinated by their reflection.” In other words, this is fairly typical dolphin behavior and not direct evidence of intoxication.

They might not even be looking at their reflections, however. It looks more like they are playing with something floating at the surface – possibly with the puffer fish. In any event, hovering upside down or vertical near the water’s surface – whether looking at their reflections or playing with objects – is pretty common dolphin behavior.

He also adds:

Consider also that it is impossible to tell if the puffer fish is releasing any toxin at all. The footage shows dolphins gently grabbing the fish as opposed to “chewing” on it. I don’t know much about puffer fish, but I am pretty sure that most of the neurotoxin they produce is located in their internal organs, which means simply mouthing the fish is unlikely to result in any/much toxin being released.

But let’s say that the dolphins were somehow able to extract some toxin from the fish. Would this result in them “getting high?” Does puffer fish toxin have an “intoxicating” effect on dolphins (or other animals)? We simply don’t know the answer to this question. Christie Wilcox has argued quite convincingly that “getting high” from tetrodotoxin (the neurotoxin puffer fish release) is probably not a thing. Exposure to the toxin is more likely to make an animal feel numb (in small doses), paralyzed (in medium doses), or dead (in high doses), as opposed to “high.” In any event, it might be that dolphins are immune to tetrodotoxin – feeling no effects whatsoever. Plenty of aquatic predators are able to consume puffer fish without being troubled/affected by this toxin (like this tiger shark – which is seemingly immune to tetrodotoxin given how often these sharks consume puffer fish). 

And finally, it's important to note that the dolphins' playful pass-the-pufferfish behaviour is not really all that rare. Gregg notes that dolphins play with all sorts of different sea creatures in this way (including fish, octopuses, crustaceans and even things like seaweed and plastic bags). And after digging into our own video archive, we’ve come up lucky! Here’s our very own clip of a puffer fish and dolphin interaction:  

Click here for more info on the BBC's "Dolphins – Spy in the Pod".