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National Black Fly Day 

It's National Black Fly Day and if you spend time near the foothills 🌄 of the San Gabriel Valley or are near running water ⛲, you've probably encountered Black Flies

May contain: insect, invertebrate, and animal
Actual image of an adult Black Fly.

3 things you need to know about Black Flies:

  1. They grow in flowing water 💦 & fly in great numbers 😲
  2. They bite around the eyes 👀 & neckline of humans & domestic animals 🐕
  3. Wearing repellent (DEET) stop the bites 🙅🏽‍♀️
Black Fly bites are painful, but they do NOT transmit diseases in L.A. County. 

Mosquitoes 🦟 VS. Black Flies

Mosquitoes are a threat to all communities because they transmit disease when they bite us. They emerge from stagnant water 💦, are bigger than black flies (about the length of the tip of one's thumb 👍🏾).

person in Mosquito costume waving

But Black Flies emerge from running water ⛲ (rivers, streams, fountains, cascades, irrigation ditches, & etc.) They're only 2-3 mm large📏 and way smaller than mosquitoes. Most importantly though, black flies painfully bite people in LA County, especially around the eyes and neckline of humans and domestic animals 🐕🐈

How you can avoid Black Fly bites: 🙅🏽‍♀️

person applying mosquito repellent
Wear repellent to avoid Black Fly bites.

Wear repellent (DEET) on exposed skin to stop the bites 👍🏾

Turn OFF personal water features for 24 hours once a week 🚫💦

** Don't forget to turn water back on to prevent mosquitoes 🦟using the stagnant water **


Continue Learning: Want to learn more about Black Fly repellents?

🖋 Written by Ally Gaspar, Outreach Assistant