Swarms of bees have come through the American Museum of Natural History, and each one gets a shampoo and blow-out upon arrival. The Museum has posted a run-down of the process on their website, noting that "the bee specimens in the Museum’s Division of Invertebrate Zoology are treated to a day of beautification before they join the research collection."
Why? The bees are often stored in alcohol when collected in the field, but researchers prefer them dry, so they're put into a vial of shampoo, shaken up, and washed off. Here's a little more on the process, from the AMNH:
The hair of bees, which helps many species gather pollen, has to be immaculately “styled” so that their anatomical features are best preserved for scientists to study. Curatorial Assistant Melody Doering is the Museum’s go-to insect stylist.
As with any visit to the salon, this starts with a good shampoo. Doering adds a single drop of soap to a vial of water, drawing a tiny bee bath. With a pair of tweezers, she gently removes the specimen from its field transport jar and places it in the soapy solution. A shake or two and a brief soak is all that’s needed to clean the alcohol from the bee’s fine hairs.
In order to get them dry, a makeshift bee dryer is used—something akin to a bicycle pump. The Museum tells us, "They have only done about 100 of these. They only need to wash specimens unfortunate enough to be preserved in alcohol; and, luckily, most do not come that way."
The Museum is pretty serious about bees, and launched a Bee Database Project over a decade ago, with specimen records entered into their Invertebrate Zoology Divisional Database. Their bee efforts have even helped identify four new species of bee in New York City.