It took us a while to figure out why: it was probably a bird-of-prey detection circuit looking for gliding motion.

A feral cat that gave birth in a family member's garage in east San Diego (not the sierras but mountainous at ~3k ft elevation) found a rattle snake on their property one time. I had to scare her away several times while running around looking for a bucket and some long sticks because she did not recognize the danger at all. It looked more like she was approaching a strange new male cat that was about to court her than a venomous snake

Regarding the cucumbers: another family member had a cat in Europe in a village around 56°N - which is near the upper limit for snakes, so he's unlikely to have ever seen any, let alone eaten one - and the cat loved cucumbers. They had a greenhouse and had to be extremely vigilant after picking cucumbers because the second they'd turn their backs the cat would proceed to take nibbles out of every single one of them in turn, even if he was given one of his own. I think your cat just likes cucumbers.

Interesting, although I suggest it much more likely that this cat also really is triggering some kind of "snake recognition circuit", it seems to be driven by some desire to make sure each cucumber is "dead". If it were only about liking cucumbers you would expect it to gobble down the nearest delicious thing it sees, which in my own observation of the felis catus, this is their default behavior when there is favored food and no danger present, they tend to act like greedy vultures, though it differs from cat to cat.

That's the problem: people are extrapolating species-wide behavior from a tiny sampling of an animal with high variability. Some feral sisters have set up shop on a family member's property and given birth to several litters so at this point I've got experience with two dozen cats over my lifetime. The natural variability in personality I've observed in three month old kittens raised in the same environment by two biological sisters (who themselves have vastly different personalities), is staggering. I have no freaking clue where people get most of their cat stereotypes.

> If it were only about liking cucumbers you would expect it to gobble down the nearest delicious thing it sees

Why? I can't imagine anyone in my family eating a cucumber after a cat has bitten it for sanitary reasons so I expect he quickly learned that the more cucumbers he nibbled on the more he got (these are home grown cucumbers, not the giant monstrosities in US supermarkets, so he'd want more than one).

In Africa, most of the storks ate snakes; including really deadly ones. They would stomp them to death. That would probably not work on pit vipers.

my pet goose does this as well with anything remotely snake-shaped.

She's used to it now, but she used to do the same hopping-dance every time she'd encounter a garden hose.

hop hop hop with her wings out to appear bigger while quickly snapping at the 'victim' with her beak and then darting to caution with her head while keeping her distance from it otherwise and continuing the stomp dance.

must just be a bird thing (the dance, not the anti-snake behavior), I have my doubts that her soft webbed-feet would do anything but perhaps scare an actual snake.