AUDIE CORNISH, host: Look out your window. How long do you think it would take to identify all the living species you see in your backyard? From a giant oak tree or the family dog right down to the microscopic level, thousands of volunteers and scientists tried to do just that on 142 square miles in one day. NPR's Ted Robbins reports on the BioBlitz outside Tucson.
TED ROBBINS: Bert Frost, the chief scientist for the National Park Service looked at the people roaming Saguaro National Park and thought, we're having a treasure hunt.
BERT FROST: Treasure hunt for the scientists, treasure hunt for the kids. What more could you ask for?
ROBBINS: If you're one of the 150 scientists normally studying Gila monsters, mountain lions or cactus, you could ask for help. That's what a BioBlitz's offers. In this case, three to five thousand volunteers showed up to help.
THERESA CRIMMINS NATIONAL PHENOLOGY NETWORK: Do you see any open flowers, any flowers on this guy?
NETWORK: Nope. Do you see any fruits?
ROBBINS: Theresa Crimmins is showing a group of students from Flowing Wells Middle school what to look for on a saguaro cactus. Crimmins is with the National Phenology Network, which studies the seasonal activity of plants and animals to understand how they adapt to climate change. They now have baseline data on this saguaro.
NETWORK: Rather than us not knowing, you're able to now say we absolutely know with confidence that on this day, October 21, 2011 here in Saguaro National Park, this cactus did not have anything on it.
ROBBINS: BioBlitzes take place all over the world. In the U.S., the Park Service has teamed up with National Geographic to hold five of them - from the Santa Monica Mountains next to L.A., to Biscayne National Park near Miami. All are close to urban areas so non-scientists will get involved in the natural world. In Joshua Nichols's case, a little too involved.
JOSHUA NICHOLS: Ouch.
ROBBINS: He backed into a cholla cactus, a species notorious for leaving spines in you.
NICHOLS: I just pulled all of them out. The last one really hurt.
ROBBINS: Lesson learned. Other volunteers went high into the mountains and deep into canyons to spend the day and night looking for plants and animals. The Park Service's Bert Frost says at every BioBlitz they've at least discovered species scientists didn't know were in the park.
FROST: The one at Biscayne, we discovered a new species to science.
ROBBINS: What was that?
FROST: It's a water bear. It's a very small critter that lives in water.
ROBBINS: It'll take a while to catalogue what was found at Saguaro National Park during this weekend's BioBlitz. But let's get real, not even all these people can find every species here in a day. Fun trying though. Ted Robbins, NPR News, Tucson.
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