A new spider species discovered in Seattle?

It's amazing what we still don't know about where we live, as new finds by scientists and amateurs are helping to rewrite textbooks. A recent discovery in the Arboretum is a case in point, but hardly unique.

Crosscut archive image.

Nature never stops surprising: Scientists believe a new species of crab spider has been found on Foster Island.

It's amazing what we still don't know about where we live, as new finds by scientists and amateurs are helping to rewrite textbooks. A recent discovery in the Arboretum is a case in point, but hardly unique.

It's the 21st Century. The days of naturalists like David Douglas and Archibald Menzies wandering the Pacific Northwest and finding discoveries new to science at every turn are long over, aren't they? Surely we know every nook and cranny of this place by now. 

And yet. ...

On a recent tour of the Burke Museum of Natural History and Culture, we came to the office of Rod Crawford. The Burke, I was told, is not known for its bug collection (mammals, fish, birds, yes), but Crawford is their spider man (technically, their Curatorial Associate of Arachnida). His office door is shut, no light shines from beneath the door. Our guide gently knocks and we hear a shuffling from inside. I am reluctant to enter, being close to arachnophobic. The door opens and a man stands there, eyes blinking like a mole, looking a bit like a character played by Wallace Shawn. He works in the dark to provide a nocturnal environment for some of his specimens, which can be heard scuttling in the background.

He's very friendly to our intrusion as we're introduced. He tells us that he has just identified what he believes is likely a new species of crab spider. Yes, a brand new species. Found where? Here in Seattle, on Foster Island, to be exact. In an email later, he elaborates: 

I could tell immediately that it was a female crab spider of the genus Philodromus, and one of the "Philodromus imbecillus" group (about 10 closely related species, of which only one, Philodromus insperatus, is known from Washington). To tell which species it was, would require dissection, which I couldn't do on a fresh specimen not yet fully preserved. So I set it aside until I came to that collection in the course of curating and cataloguing last year's material in the order in which collected. 

Having done so, I found that the internal female genitalia does not match insperatus (which occurs mainly in sagebrush country anyway), and is similar to Philodromus marxi, a species of the Atlantic states that has very different, metallic body coloration. So as far as I can tell from one specimen, it's a new species.

He says he just informed the Arboretum folks of his conclusion. In a follow-up call, UW Prof. Sarah Reichard, the Arboretum botanist and a specialist in the restoration of rare species, said the find is "cool" and gets "us geek scientists beyond excited."

Crawford needs more specimens for study, and must jump through various hoops to describe, illustrate, and demonstrate his discovery to the satisfaction of the scientific community before it's accepted. Reichard said the Arboretum is currently discussing going out to look for more, possibly this spring (little is known about the spider's life cycle, so it's an educated guess as to when they might be found in abundance).

Crawford pulls out a tray of small test tubes containing dead spiders floating in clear liquid, including this newbie to science. You almost need a magnifying glass to see some of them. The average spider is quite tiny, much smaller than a pepper corn, which makes you realize how anomalous the giant, scary ones are. (Crawford has a Web page devoted to spider myths.)

I have two immediate reactions to the news. The first: amazement that a new species might be discovered on Lake Washington, much less next to a major state highway, a place well-trafficked by joggers and nature walkers. We're not talking deep in the old growth here. The specimen was found during a so-called Bioblitz, an intensive effort involving volunteers to document and map what species of flora and fauna live in the Arboretum. The blitz, held last spring, consisted of scientists, lay people, undergrads, even kids to help them survey the park.

Another Bioblitz is being discussed for later this fall. Reichard says citizen scientists do extremely valuable work in Washington, where there is a lot yet to be discovered, especially among invertebrates like "insects, spiders and soil organisms." Even plants. A newly identified species of Indian paintbrush was found recently in the San Juan Islands.

My second thought is about the planned Highway 520 bridge expansion. Just because a spider hasn't been discovered by science before doesn't mean that it's endangered, but shouldn't the Department of Transportation be informed? Doesn't this impact the EIS for the expanded 520 bridge? Reichard says there will be discussions with WSDOT about the find.

"It's been a long time since we found a new spider species in Seattle," Crawford tells us. But he goes on to say that he's found maybe one new species a year in the region. Crawford, by the way, is a volunteer and self-taught spider expert. (His blog about last year's Bioblitz is here). He's an expert, yes, but also a passionate civilian.

It's extraordinary to me what we still don't know all the basics about where we live. As I reported recently, an outdoorsman in Oregon discovered what appear to be large white worms in the Coast Range near Salem. He's turned them over to taxonomists for study, but they might be a new species of earthworm, or a rare species, or possibly another species that hasn't been described since the 1930s. 

In 2009, another private citizen, Lee Matthews, also discovered some large white worms on his property near Leavenworth. The experts are puzzling over them, too, and have yet to report their findings, but they also could be a new species, an unknown sub-species, or perhaps the rare and much-sought Great White worm of the Palouse, a possibly endangered species of giant native earthworms that were once found in the deep prairie soils of southeastern Washington and Idaho.

One of the foremost experts on the subject of Northwest worms, William Fender, lives in Oregon and has no college degree. He comes from a family line of amateur naturalists (his mother also was a worm expert, his father was an authority on soldier beetles). The two amateur worm-hunters who made the Leavenworth and Salem discoveries were looking for worms, but neither is a trained scientist.

Also at the Burke, we learn from Prof. Liz Nesbitt, curator of invertebrate paleontology and micropaleontology, about small creatures that were long overlooked here called foraminifera, essentially amoebas that have tiny shells around them. They have been collected as fossils and as such they can yield lots of information about past environments, but countless numbers still live in Puget Sound. There is a lot we don't know about them because little research has been done. However, around the world, they have become critical to the study of pollution. Nesbitt is researching a decade's worth of water samples taken by the Department of Ecology to determine and map pollution levels in Seattle, Tacoma, and Everett bays. If you want to clean up Puget Sound, you have to do the science that tells you what's going on and where.

Foraminifera are highly sensitive to the environment, so their presence or absence can tell you about how polluted a place is, what kind of pollution is present (some species love the raw sewage dumped by Victoria, others don't). Deformations of their exterior shells are readily apparent through a microscope and might be suggestive of nasty stuff in the water. Much of the work in sorting through and counting the tiny creatures can be done by undergrads, a rare chance for them to participate in real, hands-on research early in their education.

I find this all fascinating, and startling because I've never heard of foraminifera (my ignorance is on me, of course). As someone who grew up combing Northwest beaches, I never spotted them (and wouldn't likely), and never conceived their existence, but there are literally trillions of them in our waters.

When any matter of the seashore comes up, I turn, as many Northwesterners have for decades, to Between Pacific Tides, the bible of tidepool lovers by Ed Ricketts and Jack Calvin. Ricketts, the main author and marine biologist (also without a college degree, by the way) who put it together back in the 1930s, wrote a classic that opened the life of our shorelines to the general public, that told us the names of things in their regional varieties, such as starfish, limpets, cucumbers, and crabs. Who are they, how do they behave, how do we know them, where will we find them? He was a pioneer ecologist, and his book became indispensable for those of us living on or near saltwater who go beachcombing, clam-digging, or prowling the shores by foot or boat.

Ricketts was the model for the character Doc in John Steinbeck's classic, Cannery Row, and they collaborated on The Sea of Cortez and planned a sequel devoted to Northwest waters between Washington and Alaska. The dog-eared edition of Tides I grabbed from the shelf was last updated in 1962 and has a foreword by Steinbeck. I looked up foraminifera in the index, but found only one tiny reference in the appendix under Protozoa. 

I then flipped to the foreword, and read Steinbeck on the value of Ricketts' book and the importance of "inquisitive men seeing new worlds." He wrote: 

Every new eye applied to the peep hole which looks out at the world may fish in some new beauty, and some new pattern, and the world of the human mind must be enriched by such fishing.

Or worm-hunting, or spider-catching. It takes all hands to learn the secrets of a place. After more than two centuries of scientific probing, there's a lot of work left to be done here.


Please support independent local news for all.

We rely on donations from readers like you to sustain Crosscut's in-depth reporting on issues critical to the PNW.


About the Authors & Contributors

Knute Berger

Knute Berger

Knute “Mossback” Berger is Crosscut's Editor-at-Large.