Now I know some mermaid media have mermaids that can straight up talk to fish, and then there's OTHER media where mermaids can't, so for my mermay AU (which. I think calling it Water Falls is just. So ridiculous that its sticking. Idk its hilarious) Stan kinda. Gets both.
He doesn't talk to fish. He's not Aquaman. But he doesn't. Not talk to fish. Mind you, this is a guy who drove off a cliff and woke up with a tail, hes not well versed in mermaid magic/lore and is figuring shit out as he goes. So its a COMPLETE surprise when hes gathering clams one morning and a sea lion (TERRIFYING CREATURES) pops up next to him and Stan hears, very clearly and LOUDLY,
GIVE. WANT.
He gets these impressions of speech in his brain, simple words from larger marine life. Fish dont really..have the compacity most times, occasionally he'll get a ding of a fish talking at him, but its rare. Mostly Stan "talks" to turtles, seals, sharks, big stuff.
Now "talking" isn't the right word for it. He hears these creatures because he is a creature of the sea, but he can't exactly. Talk back. He speaks English outloud to them (and sometimes Spanish and Yiddish, for practice) but its clear these creatures aren't hearing every word, just like how HES not hearing every word.
He'd describe it like talking to someone standing super far away from you. He can..sort of understand them, if they're really yelling, but mostly hes looking at body language. Fine detailed words are lost pretty much entirely, but stuff like EAT and SWIM AWAY are clear enough
However, this does not apply to whales.
Whales are the single loudest creatures Stan has every been around, and NOT hearing them is physically impossible. Whales come in remarkably clear, and Stan can hold actual conversations (its mainly small talk) and its clear everyone understands everyone. Stan likes talking to whales!
He does not particularly like talking to dolphins. He can, but dolphins speak very fast and dont linger around very much, although he has gotten a few out of a couple jams (nets) and they've in turn helped him out (sharks) so he's cool with them.
Orcas though. Stan fuckin hates Orcas.
Sometime in his first years as a mermaid, Stan accidentally pissed off a mama Orca in the Washington pod that travels for summer, and every single year since he's had to dodge, swim down, or literally fight for his life against every generation of Orcas whales with a vendetta. Those guys are assholes
They aren't trying to kill him exactly, but they seem to take enjoyment out of regularly jumping him, and no matter how often Stan bribes them or tries to talk it out, those dicks will chase him down next year.
He has conversations with them too (Orcas swear. A lot) and after a while the conversations are just the mental ocean equivalent of flipping each other off. And Orcas have excellent sonars so sometimes Stan will just be chilling in shallow Oregon water and get a ping of a 20 something Orcas whale five miles away essentially punching him in the face with the impression of a middle finger. Its utterly ridiculous.
Ford actually SEES this vendetta during a migration season when a pod takes a rest point off the coast of gravity falls and Stan climbs onto and into Ford's rowboat like a cat out of a bathtub to get away from the Orca coming up to nibble.
Ford ooos and ahhs at the juvenile who is literally RIGHT THERE, taking pictures and notes and being all excited
And meanwhile Stan and the Orca are having a staring contest and just mentally screaming "FUCK YOU" "NO, FUCK YOU!" at each other
