There were some Brazil nuts and walnuts in the first package of nuts I
gave the campus squirrels arounf Xmas (the acorn crop failed and they
faced starvation if somebdy didn't give them something).  It was a pound
of mixed nuts and it all disappeared overnight.  I bought most of the
leftover Xmas nuts from the local Walmart - pretty much all almonds.
Since those ran out I have been giving five squirrels a pound of peanuts
in the shell each week.  I fed them two days ago and saw one of them
digging up and eating almonds they had buried earlier.  The ones I've seen
look to be in good condition - better than usual for early April.

There is a story about a squirrel and black walnuts - this really
happened.  One of our prfessors set his students to inventing a device to
separate black walnut meats from the shell fragments (the difficulty doing
this is one of the reasons that black walnut meats are so expensive).
They worked on this for a couple of years. For testing purposes, they kept
burlap bags of nuts in the high bay lab - which has poorly controled
access to the outside.  After a few months, a squirrel took up residence
in the overhead pipes and beams ... and grew fat eating black walnuts.  I
suggested that the students should abandon the idea they were trying to
make work and instead hire a bunch of squirrels.  Of course, while they do
a fine job of separating the meat and shells, they won't give up the nut
meats, so that really would work in reverse of what was needed.  It took a
couple of years to get rid of the squirrel - it took abandoning the
project and getting rid of the left over nuts.