Magpies are related to crows, smart birds and fun to watch. We've had a pair of them in the yard for as long as I can remember and now a nest right next to our house in an evergreen tree. They get pretty social and make a variety of sounds / calls . A few days ago the cat was outside and a magpie was sneaking up behind him trying to peck his tail. We also have a resident pair of fox that show up once in a while and he does the same to them.
Update on the Martins , The whole colony showed up yesterday the 22nd and they are building nests. We had just that one and a couple here and there that came and left but never started building .
There are a few vids online of magpies playing with cats.