All players get a Baby Bee Fly in their forests when their Flutterpedia score reaches 1700. Not to be confused with the regular Bumblebee, it's a smaller fuzzy-looking dude with big black eyes.
Feed your Baby Bee Fly pollen from your flowers and it will grow and give you rewards like flowers and storage materials.
To Feed the Bee Fly, tap and drag it through some pollen, just like you would feed your moths! You'll see an info bar at the top of the screen that shows your Bee Fly's vital info:
You can see the Bee Fly's life stage. It starts as a baby and progresses from there.
The 'level' shows how mature your beefly is! the higher the level, the better the rewards!
The progress bar shows how much pollen the Bee Fly needs for one feeding (like a moth leveling up.) Once you've completed a feeding, the Bee Fly will give you a small reward.
When your Bee Fly is full, it will puff up and freeze in place. Tap the Bee Fly to release your reward. You can then start the feeding process again.
Feeding your Bee Fly pollen is another awesome way to get attraction flowers!