[What do I do with the mossy key?]

I found a mossy key in a tunnel that is in the koi pond, you'll need a torch to find it. The tunnel was near one of the breakers that has to be flipped to open the hatch to get the fish bowl burgl chip. I'm not sure what the key is for; I'm hoping someone can enlighten me.

[Adjust berry leather framework.]

Due to more things needing berry leather I believe it necessary to make berries more plentiful, adjust spawn time of berries, and/or adjust necessary amount of berry leather required to craft objects - etc.