[seszett]

I'm not sure about Yosemite or even nature in the US so maybe this wouldn't be an issue, but even biodegradable things like apple cores or egg shells can spread diseases to local populations of trees or birds. That's a real thing to take into account in natural parks with endemic species at least.

[heartsucker]

Huh. I didn't know. Do you have a link on that?

[seszett]

I don't have a link though, it's just something that was been repeated at length by the Natural Reserve agents and the ecobiologists to the personnel and visitors while I was on Kerguelen island (precisely about apple cores and egg shells - most of the vegetation is actually in the same Rosaceae family as apple trees, and there are many local bird species).

It makes sense to me, seeing how a single disease like chestnut blight or phylloxera can be very devastating to a population on a whole continent, it could be both as bad but also less noticeable in a natural park.