“Hello, Oscar: As you have already sensed, my interests overlap with my son Andrew's, but are somewhat different. We very much enjoyed his own experiences with you.  One of the most difficult skills to acquire in birding is learning the slight differences in bird sounds, and Andrew did learn much from you.  For our part, we saw a lot of new birds (we don't keep lists) and the wonderful Mara (if that’s how it is spelled). If we return, we might well look you up for a possible trip around the eastern part of the country.  We were impressed by your many skills. Thank you for a wonderful trip!”