Marking time on the wetlands

Expert observes the changes over 35 years

Posted: Wednesday, May 23, 2001

After observing Alaska's coastal wetlands since 1965, John Crow urges Alaskans not to take them for granted.

Drawing on a background in biology, chemistry and math, Crow initially studied the Copper River wetlands and what effect the 1964 earthquake had on the habitat of the dusky Canada goose. The quake raised those wetlands 6.3 feet; the subsequent changes and predictions of further change were the subjects of Crow's doctoral thesis at Washington State University at Pullman.

Crow is a stickler for hard data as opposed to "common sense" and "logic." "I don't take everything for granted. If someone tells me how many teeth a horse has, I still want to go and look," he said during a walk Tuesday on the Mendenhall Flats.

Data on Alaska's wetlands was rare in 1965, and what Crow has collected over the years is still the majority of information in the files of the Alaska Department of Fish and Game, said Ben Kirkpatrick of the agency's habitat and restoration division in Juneau. Crow discovered, for example, that brown bears eat more eggs as wetlands nesting areas became higher and drier.

"Brown bear predation went way up to almost one-third of the nests," Crow said at a lecture Tuesday, showing a slide of brown bear scat speckled with bits of goose egg shell.

Crow returned to the Copper River Delta three summers in a row, investigating a 55-mile-long marsh with a width of 12 to 15 miles.

In 1967, Crow began studying the greater Juneau tidelands. He marked, mapped, photographed and counted plant species on dozens of representative plots, some a few centimeters across and some as big as football fields. "My goal was that I would be able to come back to them in my 80s and re-locate many of them to one centimeter," said Crow, 59, a professor of ecology at Rutgers University in New Jersey.

Because of Alaska's wealth of relatively untouched territory, the temptation is not to be cautious enough about development, Crow said. "There is so much resources here that everybody thinks it's inexhaustible. But marshes are a very vital part of fisheries and waterfowl resources. Things may be changing slowly, but they are changing," he said. Egan Drive crosses some of his original plots, and he suggested that, even with culverts, the roadbed prevents sheet flow of moisture.

At the wetlands lookout near Lemon Creek, for example, he noted plant species diversity had lessened. "This suggests a change in water quality," he said, citing runoff and de-icing chemicals. "The marsh is definitely being impacted (by development), and it is definitely shrinking," he said.

Crow's research delves into the food web. He has proved, for example, that every acre of lower marshes produces half a ton to 2.5 tons of detritus a year. Detritus, dead organic material, becomes lunch for post-larval crabs. If marshes are depleted, it would be like "not feeding your baby," he said.

Crow speaks at noon Thursday at the Fish and Game regional office in Douglas, in the King Conference Room. The public is invited.

Most environmental impact statements prepared for development projects are "just lip service," in Crow's opinion. He advised those at Tuesday's lecture that complete mapping of wetlands and compiling a natural resources inventory should be accomplished before building a second crossing of Gastineau Channel. "A (Mendenhall wetlands) management plan, if it now exists, does not have enough data on plants so that wise decisions can be made. If you have hard data, the public will be more receptive to appreciating it," he said.

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