DEAR JOAN: We have a house at 7,000 feet elevation off Highway 4, in Skyhigh, about five miles from Bear Valley. Last month we were surprised to find that after dark we have critters eating the bird seed we put on the deck rail.

It's possible that they've been there for years and we just haven't seen them. At first we thought they were pack rats, but the tail and snout weren't right and we were seeing several of them at once, while pack rats are solitary. A search of our mammal book gave us the answer -- Northern flying squirrels. They are supposedly common in the Sierra but rarely seen because they're nocturnal, and after a lifetime of hiking and camping in the mountains neither of us had ever seen one.

A flying squirrel snacks on bird seed.Courtesy of Wendy Hillhouse
A flying squirrel snacks on bird seed. Courtesy of Wendy Hillhouse ( Wendy Hillhouse )

One night we had seven of them, and we were lucky enough to see them gliding from our roof beam and our high deck. They're pretty little creatures. Their fur is thick and looks soft, and that flat, furry tail is really unusual. They look so much like our daytime Douglas squirrels. They are the same size and coloration, except for the larger eyes and the tail. Cool, yes?

Wendy Hillhouse

Redwood City

DEAR WENDY: Very cool. The Northern flying squirrel -- they actually glide, not fly like a bird -- found in the Sierra is genetically unique to the region. They are nocturnal and their favorite food is mushrooms. Apparently they can smell out truffles by sniffing the air, and reading the signs of decaying trees and recalling what other truffle areas looked like. Smart squirrels.

It's good to know they are in the Sierra, though, because I know a lot of gardeners with squirrel-proof fences who would be very worried to learn they had to start dealing with flying versions here in the Bay Area.

DEAR JOAN: Something is eating the garden snails in my front yard. Don't get me wrong, this is a good thing!

When I go out to my driveway in the morning to retrieve my Mercury News I've been seeing many broken snail shells with no sign of their previous occupants. I find these along the concrete walkway that borders my ivy.

Near the broken shells I sometimes see what appears to be dark, rice-kernel-sized feces.

Could rats be dining on my escargot crop? The only other critters that frequent our west San Jose neighborhood are skunks, squirrels and an occasional raccoon and opossum.

R.J. Foppiano

San Jose

DEAR R.J.: At last, a reason to like rats.

Rats eat pretty much anything and judging by the description of the droppings and the proximity to the ivy, a rat's favorite nesting spot, I'd say the rats are indeed doing you a favor and eating those snails.

Raccoons, skunks, opossums and other creatures also eat snails, and they may also be joining the rats at their escargot dinners.

DEAR JOAN: We would like to share a two-minute video we compiled from the surveillance camera that overlooks our back porch. We knew we had animals visiting at night, but were quite surprised at just how much activity the infrared camera could show us.

Marilyn and John Walker

Castro Valley

DEAR MARILYN and JOHN: That is a fantastic video that shows us just how much of a jungle it is out there. I bet a lot of us have this sort of thing going on in backyards and we never even know.
