things I didn't know about butterflies

This weekend I was walking with my parents on one of the stony beaches along Lake Ontario. I'm looking down for interesting stones as we go along and suddenly see two large yellow butterflies just sitting there! They're hanging out, flapping their wings a little, and we're trying to figure out if they might be hurt. We end up taking a couple photos and moving on.

On the way back, we get to the same spot and now see at least six of that kind of butterfly fluttering around! We had no clue what was going on but a woman who studies butterflies as a hobby clued us in. She said that the butterflies are actually eating salt minerals from the soil and when they do this, it's called "puddling." (At first I thought she said "cuddling" and was greatly amused until I realized the correct word. I still prefer my version.) She also said that sometimes you can attract butterflies if you pour soapy water into a spot in your garden. The butterflies we saw that day were some kind of swallowtail but I forget which variety.

I also finally saw The Princess and the Frog. It was a nice movie, though I had a few minor problems with the plot. ( spoilers )