Training Wild Crows

Imagine if every city had training machines for pigeons and crows in every city park, with every machine training a slightly different trick.

Now imagine if the machines were set up to chain several behaviors together -- they could be made to be progressive. 

What would we train the crows?  What would we train the pigeons?

Should we train the rats?

Now, let's get down to it.  I have yard foxes.  They come every night.  What should I train them to do, now that I have trained them to come? 

I think getting them to pull a cord to lift a lid for more food will be fairly easy. 

In theory, of course. 

In theory, theory and practice are always the same, but in practice they are often quite different.
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