The Giant Spitting Earthworm Needs Your Help!

The northwestern prairies are home to an unusual creature who was once very abundant in these fertile soils. Frank Smith was the taxonomist who described this species in 1897 stating:

"This species is very abundant in that region of the country and their burrows are sometimes seen extending to a depth of over 15 feet."

The impact of this creature on the prairie ecosystem is immense, to the extent that its disappearance might threaten the prairie's viability. What is this creature whose importance cannot be understated? The giant Palouse spitting earthworm (Driloleirus americanus, the "american lily-like worm"), whose saliva is said the smell like lilies, has not been sighted in Palouse Prairie region since 1988 despite several organized expeditions to the area.

The Palouse Prairie spans western Idaho and Eastern Washington. Prairies in the United States have been shrinking dramatically under the weight of industrialized agriculture, pesticide runoff, invasive species and suburban development. Protection of this species would mean protection of the Palouse Prairie, considered by some scientists as the most endangered ecosystem in Washington. As Steve Paulson, founder of the Friends of the Clearwater, put it,

“This worm is the stuff that legends and fairytales are made of. What kid wouldn’t want to play with a three-foot-long, lily-smelling, soft pink worm that spits? A pity we’re losing it.” (cited here)

That's right, the giant Palouse spitting worm can grow up to 3 feet, is pinkish due to a lack of pigment in the skin, smells like lilies when disturbed and can dig burrows of up to 15 feet. All this living right under the noses of Washington and Idaho residents.

Landscape of the Palouse Prairie. Painting part of Oregon State University's Art About Agriculture.
The rarity of this earthworm has fueled conservationists wanting to protect the Palouse from future development. It listed as "vulnerable" under the 2007 IUCN Red List. IUCN defines a species as vulnerable when it faces a "high risk of extinction in the wild in the medium-term future." For a species to be "endangered" its estimated population must be less than 250 mature individuals and to be listed as "critically endangered" the estimated population must consist of less than 50 mature individuals. Since the original discovery in 1897 by Frank Smith, only a mere handful of sightings have taken place in that 110 year span. In fact, a 2002 survey of earthworms of 46 sites in the Palouse region failed to document its presence. To me, this should qualify as critically endangered. Though I recognize that a more thorough and quantitative study needs to be done, the fact of the matter is that this earthworm is very rare. For instance, if there have been 10 sightings in the last 110 years over an area about 8000 square miles (~20,000 square km), we can likely conclude that the population size is certainly less than 250 mature individuals and possibly under 50.

That must also be what several conservation organizations and individuals thought when they petitioned for the protection of D. americanus and its prairie habitat under the Endangered Species Act. Friends of the Clearwater, Palouse Audobon Society, Palouse Prairie Foundation and 3 individuals wrote to the Department of the Interior (pdf of petition here) in August, 2006. Two months later, the U.S. Fish and Wildlife Service responded:

"[...]. We reviewed your petition to issue an emergency rule to list the giant Palouse earthworm. Our assessment is that circumstances pertaining to the status of the species do not warrant emergency listing. If conditions change, and we determine emergency listing is warranted, an emergency rule will be developed.

We are currently required to complete a significant number of listing and critical habitat actions in Fiscal Year 2006, pursuant to court orders and judicially approved settlement agreements. Complying with these court orders, settlement agreements, and other priorities obligates all of our listing and critical habitat funding for Fiscal Year 2006. Therefore, while we are not able to further address your petition to list the giant Palouse earthworm as endangered or, alternatively, as threatened, we will address your petition as soon as funding becomes available."-Letter posted on Palouse Prairie Foundation website.

A year later, the USFWS has not conducted the required 90-day review and 12-month review. Last month, the petitioners teamed up with the Center for Biological Diversity and issued a 60-day notice of intent to sue USFWS to speed up the process. To date, the Bush administration has protected 58 species, only 25% of his father protected in his 4-year presidency (Clinton protected 522 species in his 8 years in office).

"...this ecosystem is one of the rarest on earth. Listing the giant Palouse earthworm may be the only salvation for the Palouse prairie."-O. Lynne Nelson, Friends of the Clearwater quoted from this CBD press release.