Mount St. Helens: 30 Mươi Năm Sau

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At 8:32 Sunday morning May 18, 1980, Mount St. Helens erupted, detonating a massive landslide and lateral blast that reduced the mountain's summit by 1,300 feet and destroyed 230 square miles of forest within three minutes. But the big bang and the three decades that followed also gave rise to a whole new ecosystem.

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Northwestern salamanders are thriving at new ponds built by the eruption at Mount St. Helens by keeping their gills and living their entire life as aquatic animals. That enables them to shrug off the loss of the mature forest they normally would use as terrestrial adults. Predators and parasites also haven't caught up with them yet, allowing the salamander population to boom.

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A hike takes visitors past a tree that was stuck in its current location by the blast or mudflows. The droppings of birds using the tree brought seeds, creating the stand of huckleberry to the right. Rocks scattered along the landscape were hurled by the eruption.

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Frogs gone wild: Frogs, toads and salamanders traveled much farther than scientists initially thought possible to colonize habitat after the eruption. Some red-legged frogs, such as the one above, traveled more than 2 miles as they hopped, crawled and scrambled over and around whatever was in their way.

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Charlie Crisafulli, ecologist for Pacific Northwest Research Station, looks for frog or salamander eggs in a beaver pond alive with waterfowl and amphibians. None of the habitat in this photo existed before the blast.

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Lupine turned out to be a very important colonizer after the blast at Mount St. Helens. The plant holds and enriches the soil, creating a soft landing and good start for a wide variety of other plants.

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Elk are inadvertently helping spur a resurgence of toads, as their hooves break open gopher tunnels that crisscross the deforested blast zone. Toads find the openings into the tunnels, which they use as cool, moist hidey-holes and migratory pathways. Solid populations of elk and other animals have become keystones of the ecosystem.

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"A new day": The North Fork of the Toutle River slices through what once were spectacular avalanche deposits from the eruption, which unleashed the biggest landslide in recorded history. The mounds of rock, ash and mud were so high that it was possible to walk from the towering cliff on the far shore straight across to the other side.

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Delicate mayflies help complete the suite of life assembling in new pond ecosystems at Mount St. Helens. They live only one day and provide crucial food for frogs and other hungry pond-dwellers. The amphibians also can dine on algae in the warm, sunny ponds.

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Scientists have found very few adult Northwestern salamanders like this one at the mountain's new ponds. It has shed its gills and finlike tail to become a land-dwelling animal. Nearly all the Northwestern salamanders found at the ponds remain aquatic their entire lives.

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A hiker photographs a beaver dam and lodge along the Hummocks Trail in the Mount St.Helens National Volcanic Monument. The trail winds through new ponds created by the avalanche detonated by the eruption.

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Beavers use young trees to build a huge dam along the Hummock Trail.

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Taking a fresh look at Mt. St. Helens and how the ecosystem has recovered, 30 years after the big blast. Spirit Lake can be seen from the Johnston Ridge Observatory.

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