Mount St. Helens  (MSH)
Visitors Resource Packet
Compiled/Written by Lloyd & Doris Anderson
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Rapid Recovery in the Blast Zone

Overview:  So rapid has been the recovery of life at Mount St. Helens that studies here are providing the basis for new textbooks on ecosystem dynamics. Creation scientists are using their research to expand modern understanding of how the world started over after the Noahic Flood.

Congress Provides for Scientific study:  For a decade there had been a growing sentiment for making the MSH area a national wilderness.  With the eruption a new group lent their voice to this drive--biologists interested in the recovery of life in the blast zone.  In 1982 Congress established the Mount St. Helens National Volcanic Monument, setting aside 110,000 acres where human activity would be minimized.  Most of the sensitive areas near the mountain would not even be accessible to the general public. Scientists would watch the recovery of life unaided by man.  What have these scientists learned?

Large Animals Returned Within Two Years:  Because elk have been considered forest animals, they were not expected to return for several hundred years --enough time for the forest to reestablish itself.  However, ash from the eruption grew extremely nutritious grass, causing them to begin living in the blast zone just two years after the eruption.  The grass was so nourishing that the elk could survive the extreme cold of winter in the open.  As a result the blast zone herd is the healthiest and largest elk population in the Cascades.  Deer had extraordinary numbers of twins and triplets.  Apparently some hormonal change stimulated by the environment allowed them to reproduce faster.

Spirit Lake Recovered Quickly:  Before the eruption the lake was stocked annually with 10,000 legal size rainbow trout.  The lake was so clear one could see 40’ down. The landslide raised the lake bottom 300’, causing the surface to double in size to four square miles.  The lake’s depth decreased from 180’ to 120’, was filled with organic and inorganic materials in suspension, and became a warmer environment. Almost immediately bacteria began changing the organic materials into rich fertilizer while the inorganic materials settled out.  Within three months the bacteria had fulfilled their mission and died off.  Shortly thereafter, other types of microorganisms proliferated and processed deadly materials in the lake so that within two years the lake was prepared for the return of additional lifeforms. The lake abounds with insects and aquatic creatures and fish are returning.

Insects and Rodents Repopulate by Survival and Immigration:  Some insects and rodents were in burrows or were buried in the ground under the snow pack at the time of the blast.  While many of them that climbed out or hatched perished with the ensuing eruptions, some remained sheltered and reestablished their colonies.  They also spread seed and aerated the ground that was crusted with ash.  Others came drifting in with the wind, including spiders whose silk threads served as kites.

    Such examples of rapid recovery of life in the blast zone are the special emphasis of the Coldwater Ridge Visitor Center. There you can interact with the displays and gain an appreciation for creatures like the northern pocket gophers that became heroes after the blast because, as they dug their way out to the surface, they pushed fertile pre-eruption soil onto the pumice plain, providing choice sites for early plant colonization. Pocket gophers are a symbol of the complex interaction of species with the environment.

Above are a few examples of the following elements to keep in mind when considering blast zone recovery. Additional examples are included below.

·        Biological setting before the eruption.

Example: Giant conifer trees 200 feet tall and five feet in diameter were destroyed, and cannot return quickly -- not for perhaps 200 years.

·        Changes to the setting from the eruption.

     Various zones were established depending upon three factors: force of impact, temperature suffered and the depth of burial to life forms.  Example: the pumice plain, hard and dry, for the most part supports the life of a few very specialized plants. However, in one place a crack allows a spring of water to rush forth where colorful plants can be found.

·        Casualties of the eruption based on both the blast and the destruction of former habitats. Example: Everything died in Spirit Lake until certain bacteria began the work of cleaning it up. Now fish have returned.

·        Survivors of the eruption based on the preservation of their former habitats or timing of the eruption (night vs. day, season, etc.). See previous page for northern pocket gophers.

·        Influences contributed by plants and animals carried here by wind, water or hitchhiking activities. Example: weeds sticking to the feet of ducks as they return to ponds.

·        Linkages of life forms so complex scientists admit they are beyond our comprehension. (See previous page -- Spirit Lake recovery).

·        Successive changes in life forms due to the complex interactions (such as stages of forest growth). At MSH the typical “pioneers” of a newly growing forest are not the only trees present. This has surprised scientists.

·        Boom and bust elements of population dynamics brought about by the destabilized environment. Example: Large numbers of frogs appeared for awhile on algae laden hillsides, but soon died out because the food source was not stable.

·        The generalists and specialists who colonize the destabilized environment. Pacific tree frog is a generalist at MSH -- widely adaptable; the red tree vole, on the other hand, is entirely dependent on old growth forests.

·        The effects of microorganisms on ecosystem dynamics. (as previously mentioned).

·        The human element that sometimes hinders/helps recovery. Example: Millions of dollars were appropriated to reseed hillsides and prevent erosion using helicopters. The seed either blew away or fell to the bottom of the hills, giving food to large numbers of deer mice who, when the seed was gone, began eating the bark of trees and eventually had to be poisoned.


ICR Handbook:  Material in the above list is taken from a much more precise, orderly and thorough explanation of recovery provided by Dr. Keith Swenson, a dermatologist and President of the Design Science Association in Portland, Oregon. His long interest in creation science has recently involved him in the task of writing a unit on blast zone recovery for a manual to be used with ICR tours to Mount St. Helens. His research, teamed with his medical background, continues to provide a clear and inspiring contribution to the work going on today around the mountain. One purpose of his work is to provide a basis for further study on how life would have returned after the Biblical Flood, a global catastrophe.

A further resource:

Franklin, Jerry F. 1985. “Ecosystem responses to the eruption of Mount St. Helens”. National Geographic Research. 1(2): 198-216

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