Four Legs Good, Two Legs Bad
Despite all the hooha over squirrel-proof bird feeders, I figure I am not alone in wanting the opposite. After five years of tinkering, I came up with a design that admits a squirrel of average intelligence but thwarts the scrub jays.

Materials:

• Two rectangular plastic containers (Hershey's Cocoa or similar) and one lid.
• Four hinged metal rings, about 3/4 inch in diameter.
• About 8 inches of lightweight chain.
• A few nails or tacks.

Assembly:

• Cut out the bottom of one of the cocoa containers.
• Poke two holes at one edge of the lid and corresponding holes at the top of the bottomless cocoa container. Use two of the rings to hinge the lid to the container.
• At the other edge of the lid, poke a hole near one corner, and then a corresponding hole on the cocoa container. Put the remaining two rings in the holes. Run the lower ring through a link at the end of the chain, and the lid ring through a link about four inches up the chain. Close the rings.
• Near the bottom of the other container cut a small slot to let water drain out.

Mounting: Ideally, this is mounted on a plank fence that has a crossbeam about eight inches below the top.

• Stand the lidless cocoa container on the cross beam, with the rain hole facing out, and nail or tack it down through the bottom.
• Insert the bottomless container into the tacked-down one, with the lid hinges away from the fence. Push it down maybe a couple inches, so it can't easily be knocked off.
• Fill halfway (or less) with nuts.

Use/adjustments:

• A savvy squirrel will stand on top of the plank, open the lid and tip in to get a nut, letting the lid rest on his back. The jays won't go in if the lid isn't going to stay open on its own. Watch to make sure the chain is long enough that the squirrels can get in, but not so long that the lid flops backward and supports itself. Keeping the slack hanging off the top ring helps the lid fall shut.
• If the bin is too deep for the squirrels to grab the nuts, shove the top part down a little farther. (Possibly this idea will work with just one lidded container. For me, the stacked assembly preceded the lid, so I left it that way.)
• A frustrated squirrel will sometimes pull the top container out of the tacked-down part. You might want to duct-tape them together.
• Squirrels also chew stuff, so string is not a good substitute for chain and metal rings. If you don't fill the bin too high, they aren't tempted to do much damage to the container itself.

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