Can a house sparrow swim?
Not very well. If you're asking if they can swim like a duck or a penguin, then no. But a bird that finds itself in the middle of a pond will sort of flail/paddle around in an attempt to get back to land.
Legally the only way you can move a sparrow nest is if it is a house sparrow nest. These are not native to the US and are considered an invasive species. If it is not a house sparrow no you can't move it. The Migratory Bird Treaty Act makes it illegal. See the related link below for more information.
Depends on the species, most native sparrows have little or no sexual dimorphism, while the English or house sparrow,has the male bird with a dark cap and throat patch while the female is a drab, gray brown bird. The English sparrow is an introduced European species in the U.S., and is not a true sparrow, but a Weaver Finch.