SOS Forests

Artillery Bombardment, Butterflies, and Anthropogenic Fire

The Tacoma Tribune reports that efforts to restore the Taylor’s checkerspot butterfly in Puget Sound are most successful at the Fort Lewis artillery range.

Does that mean the butterflies are ecologically adapted to artillery bombardment?

‘Just a bug, but a very beautiful bug’

Back from the edge: Checkerspot butterflies thrive in new prairie home

by John Dodge, Tacoma News Tribune, 05/25/10 [here]

Monday was a reluctant moving day for a batch of brightly colored Taylor’s checkerspot butterflies that began life at the Oregon Zoo in Portland and will end it soon on a South Sound prairie preserve near Littlerock.

The release of 60 adult butterflies was the latest chapter in a five-year project to bring the black, reddish-orange and cream-colored insect back from the verge of extinction.

Once found at more than 70 sites from Vancouver Island to the Willamette Valley in Oregon, the only self-supported population is limited to, of all places, the artillery impact zone at Joint Base Lewis-McChord.

The decline, which makes them a candidate for listing under the federal Endangered Species Act, is traced to fragmented and degraded prairie habitat, development and maybe even climate change, according to Hannah Anderson, a rare species program manager for The Nature Conservancy.

But there’s growing evidence that efforts to establish a population at the prairie site near Littlerock is paying dividends, said state Fish and Wildlife biologist Mary Linders. … [more]

Bombs away for butterflies?

Not exactly. Retired DNR forest soil scientist Ken Schlichte (frequent contributor to News From the Salmon Front and other W.I.S.E. subsites) offers a more nuanced explanation:

PRAIRIES: Burning required to maintain habitat

by Ken A. Schlichte, Letter to the Editor, Tacoma News Tribune, 05/25/10 [here]

Re: “‘Just a bug, but a very beautiful bug’” (TNT, 5-25).

The state Department of Fish and Wildlife and others have reported that the prairies of the South Puget Sound area developed by replacing forests during a warm-dry climatic period around 10,000 to 7,000 years ago. Temperatures have been cooler for thousands of years since this warmer period, known as the Holocene Maximum, but these prairies were maintained against naturally advancing forest vegetation by Native American prairie burning.

Native American prairie burning ended in the 1800s, and prairie habitat suitable for the Taylor checkerspot then became more fragmented and degraded as forest vegetation naturally reclaimed these prairies. But the fires escaping from the Joint Base Lewis-McChord artillery impact zone have maintained the surrounding prairie habitat with the only self-supported population of the Taylor checkerspot.

Native American prairie burning and artillery impact fires have maintained the prairie habitat for the Taylor’s checkerspot and other prairie species during the thousands of years of cooler temperatures since the Holocene Maximum. These cooler temperatures require continued prairie burning in order to maintain our remaining prairie habitat against the naturally advancing forest vegetation.

Mr. Schlichte’s assessment is well-supported by the latest and best available science. The W.I.S.E. Colloquium: History of Western Landscapes includes the following papers and book review:

Daniela Joy Shebitz, Sarah Hay den Reichard and Peter W Dunwiddie. 2009. Ecological and Cultural Significance of Burning Beargrass Habitat on the Olympic Peninsula, Washington. Ecological Restoration Vol, 27. No. 3, 2009 [here].

David Peter and Daniela Shebitz. 2006. Historic Anthropogenically Maintained Bear Grass Savannas of the Southeastern Olympic Peninsula. Restoration Ecology. Vol. 14, No. 4, pp. 605–615 [here].

Linda Storm and Daniela Shebitz. 2006. Evaluating the Purpose, Extent, and Ecological Restoration Applications of Indigenous Burning Practices in Southwestern Washington. Ecological Restoration, Vol. 24, No. 4, 2006 [here]

Bob Zybach. 2001. The Alseya Valley Prairie Complex, ca. 1850: Native Landscapes in Western GLO Surveys. IN Changing Landscapes: Proceedings of the 5th and 6th Annual Coquille Cultural Preservation Conferences 2001 and 2002, Don Ivy and R. Scott Byram (eds.), Coquille Indian Tribe, North Bend, Oregon: pp. 161-188 [here].

Mark Vellend, Anne D. Bjorkman, Alan McConchie. 2008. Environmentally biased fragmentation of oak savanna habitat on southeastern Vancouver Island, Canada. Biological Conservation 141(2008) pp. 2576-2584 [here].

Boyd, Robert, editor. Indians, Fire, and the Land in the Pacific Northwest. 1999. Oregon State University Press [here].

All the above report similar findings, namely that anthropogenic (human-set) fires have maintained West Coast prairies for thousands of years.

Lightning is rare in western Washington, Oregon, and British Columbia, and when thunderstorms do occur here, they are generally accompanied by abundant rainfall. Lightning does not ignite fires in this climate. But fires have maintained prairies here during the entire Holocene. Without frequent fire, trees invade.

As most people know, western Washington, Oregon, and British Columbia are home to the genetically superior Douglas-fir (the only conifer genus with 13 haploid chromosomes — the rest have 12), and the most aggressive weed in the world. The genus Pseudosuga is found from Mexico to Alaska and around the Pacific Rim to Japan and China. Here in the heart of its range, Douglas-fir is the fastest growing, tallest, most dominant plant (quite possibly in the whole world).

A carpet of grass and meadow plants can’t resist invasion by Douglas-fir — not on their own. In the absence of fire, West Coast prairies are overrun by Douglas-fir in a matter of years (a decade or two at the most). Lightning fires are rarer than rare here, yet prairies were once widespread. Now prairies seem to be persisting only where artillery rounds blow invading trees to smithereens.

Ergo and deductively, based on a variety of oral histories, settler journals, fossil pollen, and other lines of evidence, it must have been human-set fires that maintained the habitat for checkerspot butterflies during the Holocene.

Without people and our most ancient tool, fire, chances are good that the checkspots would have gone extinct or at least would have been extirpated from regions where lightning fires are rare. Indeed, in the absence of anthropogenic fire over the last 100 to 150 years, the checkerspot population has plummeted. Except on artillery ranges, that is.

Note: coming soon to the digital pages of W.I.S.E.: two of the most profound and well-researched papers ever written about anthropogenic fire — real treats for you aficionados of authentic landscape history and forest development. Get ready for pure gold in the form of exemplary science.