Smartphone Apps Enable a New Phenomenon: the Grassroots 'Bio-blitz'

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On a sunny day in May when 60 people canvassed San Francisco's McLaren Park and logged sightings of more than 200 species of plants and animals in just three hours, it seemed like a coming-of-age for smartphone-powered citizen science: At this point, just about anyone can do it and produce a remarkable quantity of usable data.

Traditional bioblitzes often include scientists intensively collecting specimens over a 24-hour period. That takes special equipment and, depending on the species and the park, special permits. A smartphone-powered bioblitz skips the specimens in favor of map coordinates and photos. Without the need for permits or special nets and traps, the McLaren Park Urban Bioblitz could be almost entirely grassroots, fueled by two all-volunteer groups, Nerds for Nature (which I helped found) and Save McLaren Park, with major assists from and Bay Nature Institute.

"In terms of research on biodiversity and biogeography, like distribution of bird species, this data is extremely valuable," said Scott Loarie, iNaturalist's codirector and a research fellow at Stanford. Before the blitz, Loarie had checked existing museum records for biological specimens collected at McLaren park and found almost none. "We were able to gather orders of magnitude more observations in just a few hours compared to 25 specimens in the history of collecting."

Using iNaturalist's mobile app, the group flew through the 300-acre park in three hours and racked up more than 1,250 sightings. The near ubiquity of smartphones is what makes an event like this possible: Just about everyone is walking around with a device capable of things that, a decade ago, would have been the purview of professionals with an armload of gadgets, and people are so comfortable using map and photo apps that there's almost no training required. (Correctly identifying species is another matter, but luckily iNaturalist has a good online community that helps out with that.)


"When the city developed the [San Francisco] Natural Areas Plan back in the 90s, there was this huge project to get all these professionals mapping out all this stuff," said Ken McGary, a leader of Save McLaren Park who lives nearby. "Now 15 or 20 years later, we did something similar with a few experts and volunteers. And we're also inspiring a new group of naturalists."

Now, according to Jean Farrington, director of lifelong learning at the California Academy of Sciences, the academy hopes to use the McLaren Bioblitz as a model for a series of bioblitzes, partnering with groups like Nerds for Nature, Bay Nature, and local park groups to document species across San Francisco as part of an upcoming San Francisco biodiversity citizen science campaign.

umber skippers, Ken-ichi Ueda, creative commons
umber skippers, photo by Ken-ichi Ueda, creative commons

iNaturalist was the brainchild of Ken-ichi Ueda: He and other students at UC Berkeley created it for a masters project in 2008. Since then, as KQED has reported in the past, it's gotten bigger and better. iNat users are tracking pikas in the High Sierra, logging global amphibian sightings, and chronicling the effects of climate change at Stanford's Jasper Ridge.

But this was the first time Ueda and Loarie helped organize an on-the-ground blitz. None of us knew if turning novices loose on the park with minimal guidance would work. It did. "You don't need to know what you're looking at, but you can still record interesting and scientifically relevant data," said Ueda. "The one pipevine swallowtail was recorded by a guy who just showed up and wasn't looking for it."

We divided up into four teams and fanned out across the park, trying to find as many different kinds of plants and animals as we could in just three hours, and recording our sightings using the iNaturalist smartphone app. Blitzers found the expected—like a raven or a scrub jay—but also the unexpected, like that pipevine swallowtail butterfly, a Lazuli bunting and oddest of all, a dead Anna's hummingbird resting in a cala lily.

Logging a plant with giant leaves. Photo by Tamara Schwarz
One team was fascinated by this South American import (genus Gunnera) with enormous leaves and spiny stalks. Photo by Tamara Schwarz.

And people had a lot of fun making those discoveries: "I guess it was pretty obvious that we were having a good time," said one blitzer, "because a woman who happened to be jogging through the park stopped me to ask what group we were with and how she can join." At the end of the day, we watched as the numbers rolled in on iNaturalist's leaderboard page. Once those sightings have confirmed species IDs, the data flows to both the Global Biodiversity Information Facility (GBIF) and the Encyclopedia of Life, where researchers all over the world can make use of it. Loarie tells me that some 66,000 verified research-grade observations are now in the GBIF database (out of more than 200,000 total sightings on iNat).

Blitzers at McLaren Park, photo by Tamara Schwarz
Blitzers at McLaren Park, photo by Tamara Schwarz

iNaturalist data can be used not just for academic research, but for grassroots restoration and outreach as well. On Saturday, we heard about an SF State student using iNaturalist data for research on Pacific chorus frogs. Local activists concerned about a new plan for the Jerry Garcia Amphitheater want to log wildlife in that area. Amber Hasselbring, director of Nature in the City, and lepidopterist Liam O'Brien are using the app to track butterflies on Market Street.

Beyond all those specific cases, I love just looking at the cast of characters we know live in a park once it's gotten the attention of iNaturalist users. Here's McLaren Park's iNaturalist page. Who wouldn't want to go there?

Thanks to Tony Iwane for producing the event video, and to Ken McGary, Tom Scott, Ken-ichi Ueda, Scott Loarie, Ryan Kaldari, Liam O'Brien, and many others for making the event possible.