The article indicates that it was 841's mother who was likely fed by humans. 841 was born in captivity and care was taken to prevent human association:
The pup was raised by her mother until she was weaned, then moved to the Monterey Bay Aquarium. To bolster her chances for success upon release, 841’s caretakers took measures to prevent the otter from forming positive associations with humans, including wearing masks and ponchos that obscured their appearance when they were around her.
"Nearly all domestic animals have been shown to have smaller brains than their wild counterparts [1–7]. Those that are most important to humans, mostly for consumption or companionship, display the greatest amount of reduction. These include pigs (approx. 34%) [8] and sheep (approx. 24%) [2], and dogs (approx. 29%) [3] and cats (approx. 24%) [3], whose brains reduce more than twice as much as those of other domestics"
"Bullfighting cattle, which are bred for fighting and aggressive temperament, have much larger brains than dairy breeds, which are intensively selected for docility."
So if you are aggressive and violent, you have a bigger brain, but does brain size correlate to intelligent? Maybe the recent musk v zuck is an indication of throwing off those social constraints.
Either way, the state stating they have to kill the otter would mean this is a smart otter not fearful of predators like humans. Interesting that hormones are also cited for the increased aggression, is the oestrogen choline pathways giving the otter ideas?
As if the whole captivity experience isn't inextricably colored by those silly humans running the show and all their associated machinations. Ponchos? seriously?
The pup was raised by her mother until she was weaned, then moved to the Monterey Bay Aquarium. To bolster her chances for success upon release, 841’s caretakers took measures to prevent the otter from forming positive associations with humans, including wearing masks and ponchos that obscured their appearance when they were around her.