Calling all citizen scientists! The Natural History Museum of Los Angeles County and the California Academy of Sciences in San Francisco are launching the third annual City Nature Challenge. It’s an incredible opportunity to show your civic pride while doing real science.

People around the world will compete to catalog the greatest amount of wildlife in their cities. Download the iNaturalist app before April 26 (that’s this Friday), then start snapping pictures of all the wildlife in your city, be it plant, animal, fungi, or slime mold.

Scientists can’t be everywhere at once, so without the work of citizen scientists, they’d miss out on some incredible finds. In fact, in last year’s Challenge, an Asian hammerhead worm was observed in the Bay Area for the first time ever.

There will also be some great events where you can participate: the Cabrillo Marine Aquarium in San Pedro will host tidal pool searches on Saturday and Sunday and the Natural History Museum will host a BioBlitz at Devil’s Punchbowl in the Antelope Valley on Saturday.

San Francisco won last year; let’s see if LA can make a comeback!