Why do Hoverflies hover in one spot?
Similarly, why do honey bees hover in one spot?
Bees share with hummingbirds the ability to hover in one spot midair. They use it to explore flowers for nectar, same as hummingbirds. I have often seen male carpenter bees hovering in one spot, far from flowers. Female carpenter bees are solid black, but the males are yellowish and hairy looking.
Similarly, you may ask, why are Hoverflies attracted to me?
Adult hover flies feed mostly on nectar and pollen and can often be seen hovering around flowers. They are considered a very important group of pollinators outside of the bees. Some hover flies are attracted to the salt in human sweat and will land on exposed skin.
Just fill up a plastic container, such as a milk carton, with water and sawdust, and leave it in your garden to provide habitat for hoverflies with semiaquatic larvae.