We live in the Sierra Nevada foothills in the Mariposa area. We have a common pesky little fly (much smaller than a house fly) that seems to be growing in numbers each summer. They fly in your face, try to get in your eyes or mouth. We have to wear mosquito nets when we walk or hike. I would like to know if it is co2 that these critters are attracted to in which case, we could at least get some relief on our patio by getting one of the devices like Mosquito Magnet or Dynatrap. Any idea what they are and if such a device would work?
Flies are usually impossible to ID even with images, and a description alone is useless. I'm sorry. You need to take intact specimens to a local entomologist who can put them under a microscope and render a more concrete verdict than I can over the internet.