“It’s so embarrassing,” cries young Ajay the Blue Jay…
“Here I am completing my first adult molt and looking dapper as Dad—
“But before I can grow out my glorious crest, down swoops this dirty old miniature fly and totally ruins my style!
“No matter how I squirm and shake, he keeps hanging on. What’s the deal here!”
If you watch your bird friends closely, chances are you may have seen a tiny fly like this from time to time. Scientists call them Hippobocidae or Keds for short, and they’re actually no laughing matter.
Like the much larger horse and deer flies that can make life miserable for livestock and the humans who tend them, Keds inflict painful bites on songbirds.
Like mosquitoes, Keds have special mouth parts that attach to the victim and drill down to collect a generous meal of bird blood before they fly off to annoy another.
There are 200 species of Keds, and many appear to specialize in just one bird species. Thus, Keds on Boobies aren’t interested in Frigate Birds, and vice-versa. And Keds don’t appear to go for humans—extremely fortunate, because they’re suspected of carrying West Nile Virus. Yuck!
There’s one more fact about these “bird flies” I can’t resist sharing —they don’t lay eggs
Instead the female Hippoboscid gives birth to a live baby larva—just one. The larva feeds off ‘’insect milk” inside its mother’s womb and spins itself into a pupa before mama finally deposits her baby into a bird nest.
So these flies in many ways imitate the life cycle of a mammal!
Happy ending: the next time I spotted Ajay, his crest had started to grow out, and the mini-fly was gone! As soon as I can, I’ll post a photograph of Ajay in full adult glory—feeling, no doubt, much relieved.

