Swallows have small narrow pointed wings, short bills and some have forked tails. They spend a lot of time in the air hunting insects and are agile flyers. They have many nesting habits which can include holes in trees, burrows in banks, nest boxes or even using mud to make homes on buildings. Swallows will migrate and spend winters where more insects are abundant. Purple Martins are a member of this family and rely more on human made housing which originated from gourds which were hung next to villages out East. Now Purple Martens do phenomenal jobs of insect control.