In Search Of L.A.'s Slimiest Residents
"Are you looking for something? Did you lose something?" A college student wandered by, eyeing us quizzically. It's probably not every day that three fully-grown adults are spotted crawling through the carefully manicured planters of a university campus on a damp January evening. Jann Vendetti looked up. "No, we're looking for slugs," she said.
Vendetti works with the Natural History Museum of Los Angeles County. She's a malacologist; she studies mollusks. This group of animals is the second largest on Earth (after the arthropods), and includes critters like octopuses and squids, clams and chitons, snails and slugs. We met on a Friday night on the UCLA campus to go on a snail and slug hunt. With us was our guide, a third year UCLA transfer student named Cedric Lee.
In the last few years, researchers at the Natural History Museum have begun to turn some of their attention away from their expansive specimen collections and from expeditions to far-flung locales, opting instead to try to learn just what else, besides us, calls Los Angeles home.
But most of L.A. is private property, which means that scientists can't just wander around lifting up every rock and log to see who might scurry away. (That's called trespassing, and it's frowned upon by museum higher-ups, and by law enforcement.)
That's why the newly formed Urban Nature Research Center at NHM has turned to citizen scientists, regular folks who can spot an interesting-looking critter on their own properties, snap a quick photo or two with their smartphones, and upload them to an app called iNaturalist. Researchers can then attempt to ID the observations and combine all the data to understand which species live where. In all, more than two hundred volunteers have signed up to seek out and document the snails and slugs in their neighborhoods twice each month.
Vendetti's aptly named project is called SLIME, which stands for Snails and Slugs Living in Metropolitan Environments. (Malacologists seem to revel in the fact that most folks regard their critters of interest as kind of icky; Vendetti is a member of a professional organization called Southern California Unified Malacologists, or SCUM. "Slugs have a gross out factor. I don't know why, but they do," she says.)
The recent El Niño-driven storms have offered up a molluscan bounty for gastropod enthusiasts to document. "When it rains, that's when they're free to come out and not die of heat and lack of moisture, so they find their mates, lay their eggs, eat, and hang around for a while," she says. Then they burrow back into the ground or hide under rocks where it's a bit cooler and wetter, waiting for the next opportunity to reproduce. (You have until April 14 to participate in the museum's El Niño Snailblitz.)
Lee, an ecology and experimental biology major who lives in Monterey Park and commutes to UCLA, wasn't at first particularly interested in snails or slugs. As a kid, he spent lots of time crawling around chasing after bugs and lizards, but then he "got sidetracked by others things," he says, "like video games." (For her part, Vendetti can trace her interest in the oft-overlooked creatures to a childhood spent exploring east coast tidepools.)
Years later, Lee rediscovered his love of nature and ecology. And after he saw some of the local species in the NHM collections, he marveled at the biodiversity he must have overlooked while working to map local vegetation for a separate project. As of this writing, he's become the most prolific contributor to the SLIME study, with 161 observations and 27 species, the most of anyone who has contributed to the effort so far. One of them is a new record for LA County.
It's not just that Vendetti and her colleagues want a census of our slimy neighbors for purely academic purposes, though that's part of it. Her background is in marine slugs, so when she decided to turn her attention to the terrestrial gastropods (the group of animals that includes snails and slugs) of LA county, she tried to find the right book to study. The problem? "There is no book," she says. As with lizards and birds and flies and everything else, researchers have historically gone abroad to study biodiversity and all but ignored their own backyards.
Then there's the practical part. Our native species - all twenty-one of them, or so - mostly feast upon garden detritus, helping like earthworms to decompose dead plant matter, allowing the nutrients locked away in it to continue their cycle through the ecosystem. But some snails and slugs, especially the non-native species, can prey upon native species or carry disease, and can wreak havoc on gardens, farms, and orchards. With two major shipping ports nearby, all it takes is a couple snails or eggs to hitch a ride in a potted plant and a new species becomes introduced. If it's a hardy species able to adapt to a variety of habitats, it can quickly multiply and spread.
Over the course of a single hour, Lee, Vendetti, and I crawled around three landscaped planters surrounding UCLA's Powell Library. This is far from a natural landscape. Highly managed and immaculately arranged, it's likely that the university's landscaping department brings in new plants all the time. Combined with the time of day (most gastropods are nocturnal) and the moist air, Lee and Vendetti's expert eyes allowed us to document a total of eight different species. There was the ubiquitous European garden snail of course, the most familiar species to just about everyone, plus common chrysalis snails, garden slugs, a striped greenhouse slug, some appleseed snails, a few glass snail called Oxychilus draparnaudi, and a pair of milk slugs, so named for the milky white slime they leave behind as they crawl along.
Lee also brought a few specimens he'd collected earlier in the week from other spots on campus: slippery moss snails, rounded snails, orchid snails, and eccentric grass snails.
Surrounding one sprinkler control box we found an aggregation of at least sixteen European garden snails, ostensibly taking advantage of the drips escaping the exposed, leaky pipes.
This is yet another reminder that wildlife exists everywhere, that wild creatures have figured out how to take advantage of every nook and cranny in our artificial urban environments. "Sometimes the biodiversity that's around you is unappreciated because this is where you live, and you feel like its not where [other] things live," says Vendetti. "We have this idea that nature exists in some place you have to drive to, but biodiversity is around us all the time."