JEAN LAKE – Another big fire of the type many have been expecting since spruce-bark beetles devasted Southcentral Alaska forests in the 1990s has swept across the Kenai National Wildlife Refuge south of Alaska’s largest city, but the results do not appear near as grim as those found in the wake of fires north of Anchorage that consumed at least 80 structures.
When the Kenai’s long-burning, Swan Lake fire broke out to the south and jumped the Sterling Highway earlier this week, state and federal fire crews were able to get everyone safely out of the area and protect the community of Cooper Landing to the north.
Sparked by a lightning strike in early June, the Swan Lake fire had looked for a time to be under control but roared to life when winds began whipping across the Peninsula. It has now burned nearly 150,000 acres in the Mystery Creek and Chickaloon River drainages and advanced into the refuge’s Skilak Wildlife Recreation Area.
The scent of woodsmoke in the air left Ted Spraker, the former area wildlife biologist for the Alaska Department of Fish and Game and now the chair of the Alaska Board of Game, in Soldotna smelling a new boom in moose numbers in future years.
And an on the ground examination of conditions in the wake of the fire indicated that might indeed be what happens. The still-smoldering lands near the Sterling had burned deep into the duff layer of the forest.
This the mark of the kind of fire that sets the stage for heavy regrowth of birch and willows, the best of Alaska moose food, according to the U.S. Forest Service.
“Few, if any, feltleaf willow seedlings are likely to establish following low-severity fire because organic soils are only partially consumed and prevent establishment,” the agency’s scientists have found. “Following severe fires, however, the primary mode of feltleaf willow recovery is likely seedling establishment. Severe fires that burn deeply into organic soils may kill feltleaf willows but expose mineral soils, which provide excellent seed beds for feltleaf willow. Early summer fires that occur prior to seed dispersal are most likely to benefit feltleaf willow because seeds would be available to germinate on the newly burned areas soon after fire.”
Fire was for centuries a driving force in shaping the habitat of a Kenai refuge that began life as the Kenai National Moose Range in 1941 by order of President Franklin D. Roosevelt. Scientists had already in those years begun to suspect that the removal of wolves from the Kenai, and wildfire were responsible for big increases in the moose population.
“There had been three large fires. The first occurred in 1871, the second in 1891, and the third in 1910,” Alaska historian Claus Naske has written. “The first of these left so many fallen trees that hiking across country became exceedingly difficult.
“The 1910 fire cleaned the downed material. Moose rapidly increased thereafter. During the winter of 1921-22 with feed low, large numbers of moose migrated east across steep ridges resulting in the natural restocking of moose in the Resurrection River area along the Alaska Railroad, which had been depleted of moose for years” due to overhunting.
Moose Range designation brought modern wildlife management to the Peninsula and decades of excellent moose hunting followed even as spruce forests once again began to replace willow thickets and young stands of birch that provided the food necessary to support large numbers of moose.
Forest Service plant ecologist Michele Plotkin, who died tragically in an Alaska avalanche in 2000, would later conclude the boom-bust cycle for moose tied to habitat type went back to far before white contact in Alaska.
“Within the historic burns, remnants of older stumps and isolated residual trees reveal mature forests existed prior to disturbance,” she wrote in a 1997 Fire History Disturbance Study. “Needleleaf forests adjacent to these historic burns have ages greater than 200 years before present (ybp). The ages of living Lutz spruce and mountain hemlock with the mature forests sampled are greater than 200 ybp, (but) subsurface charcoal is greater than 500 ybp.”
Radiocarbon dating of the charcoal pointed to a fire history at least 3,000 years long, leading Plotkin to finger fire “as an important disturbance process over many millennia in this transitional climate” and to warn – more than 20 year ago – that “the historical records of fires and tree ages, together with the present mature forest and beetle-kill fuel loads suggests that the next interval of stand-regenerating fires is near.”
The first big fire to follow that report – The Funny River Fire – burned almost 200,000 acres in 2014, but remained generally south of the Kenai River and east of the Kenai-Soldotna area in a little-visited portion of the refuge.
The latest fire, which for a time closed the Sterling Highway linking Kenai and Anchorage, has been much more noticeable.
A natural phenomenon in most inland Alaska ecosystems, fire been controlled for decades along the limited Alaska road system. Regular fire fighting efforts have limited the damage from fire but allowed fuel loads to increase. Meanwhile, the consequences of beetle-kills of large expanses of forest have only added to the fuel-load danger.
Once the trees die, Plotkin observed, a lot of sunlight streams into the forest and “blue joint reed grass has been show to increase from under 5 percent to over 50 percent five years after a spruce beetle attack. Total fuel loadings (then) increased from about 10 tons per acre to 35 to 100 tons per acre. When sustained dry conditions occur in the spring fire season, fire danger can increase very rapidly. Fuel loadings that are heavy with an abundance of flashy surface fuels can spread fire into beetle-killed spruce jackstraw resulting in hot, intense fires.”
A naturally sparked fire spreading into beetle-killed spruce to become a hot, intense fire is pretty much what happened on the Kenai this year, although the sustained dry conditions came during an unusually, warm, near-drought summer.
Some have been quick to blame this on global warming, though most climate-change models predict a warmer-wetter, coastal Alaska rather than a hotter-drier one. The models suggest the Juneau climate becomes more like that of Seattle, and the Anchorage-Kenai climate more like Juneau.
Juneau is in the coastal rain forest where fires are rare. Despite that, many news outlets have been quick to link the 2019 Anchorage-area fires and the far-more-common Interior fires to the hottest July on record in the state.
The number of fires had increased to 667 by Thursday and the acres burned had crept over 2.5 million, according to Tim Mowry, a spokesman for the Alaska Department of Natural Resources, but that’s far from the record 6.6 million acres that burned 15 years ago, the 5.1 million acres that burned four years ago, the more than 4.2 million acres that burned in 1969 and the nearly 3.2 million acres that burned in 1990.
And though wildfire are generally thought of as a “bad” thing, University of Alaska Fairbanks scientists portrayed fire somewhat differently in “Wildland Fire in Alaska: A History of Organized Fire Suppression and Management in the Last Frontier” in 2006.
“During the past century, we reacted to wildland fire in much the same way we reacted to predators,” wrote authors Susan Todd and Holly Ann Jewkes. “At the beginning of the century, we saw fires—and predators—as something to eliminate. We were remarkably
successful at doing so; we eradicated predators from most of their range in the Lower 48 States and, for a time, we almost eliminated fire.
“But by midcentury, many scientists realized that both fire and predators play important roles in ecosystems and that their elimination had unexpected consequences. Where
predators were eradicated, prey species such as deer became overabundant and died slow deaths from starvation. Similarly, when fire was eliminated from areas where it had once been frequent, fuels in the form of underbrush and dead and downed wood became overabundant, increasing the potential for a catastrophic fire.”
“What many in the media, and in the general public, failed to understand at the time was that fire — even fire of this magnitude — was necessary to maintain the overall health of Yellowstone’s ecosystem,” National Public Radio reported a decade later.
Now, a little over a decade on from that, the narrative is shifting again with climate change the focus of attention. This year, NPR was focused on “How Arctic Fires Are Impacting Earth’s Atmosphere” and zeroed in on Alaska even though only about 5 percent of the hundreds of fires burning in the state are actually in the Arctic.
There is, however, no doubt the Alaska fires are adding carbon dioxide to the atmosphere or that the trendline shows the annual acreage burned in Alaska slowly but steadily increasing since 1965 despite huge seasonal variations in the number and size of wildfires.
“Recent changes in climate have resulted in increases in the frequency of large fire years and have resulted in a dramatic increase in extreme fire events,” Eric S. Kasischke from the University of Maryland and colleagues concluded in a peer-reviewed paper published at NRC Research Press in 2010. “Four of the 11 largest fire years on record since 1940 have occurred between 2002 and 2009, and the increase in frequency of large fire years has been accompanied by a fourfold increase in late-season burning that occurs because large and increasing numbers of extreme fire events in remote areas are too large to control.
“The evidence now points toward the fire regime being vulnerable to climate warming over the near term with the potential for a continuation of large fire years and events and more late-season burning being high.”
The good news is that they expect the problem to cure itself.
“At some point, however, increases in early-successional vegetation combined with changes to postfire succession in black spruce forests will reduce the vulnerability
of the landscape to fire spread,” they wrote.
As the Alaska Regional of the National Park Service notes, “fires occur infrequently and are usually fairly small in the forests of aspen, cottonwood, and birch. It is in Denali’s northwest taiga and tundra, where black spruce is abundant and where precipitation is limited, that fire is a dominant process.”
All the smoke in the air over the Anchorage Metro Area seems to have moderated what was by local standards an overheated summer. With smoke blocking the sun rays, temperatures have returned to normal for this time of year, and temperatures in Willow fell to near freezing on Monday with the dewpoint low enough that some people reported ice forming in their pets’ dog dishes.