Where are keys in snow-pack park

the blue key is at the forest/beach: a snake is wrapped around it, to get it you must throw a fish to distract the snake and then grab the key.

the silver key is on the iceberg that you can go to for free (first area you were able to go to with the balloons): it is in one of the square ice chunks that you can pick up and throw.

i've only gotten that far in the game so thats all i know...i hope this helped :)