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Volunteers search for eggs in bid to save Glenwood frogs

At Conboy Lake Wildlife Refuge

It's an odd job if ever there was one: wading through shallow lake water, looking for egg masses. But those working to help ensure the safety of a population of endangered frogs at the Conboy Lake National Wildlife Refuge near Glenwood are finding no shortage of volunteers.

The Oregon spotted frogs at Conboy Lake represent the largest population of the frogs in the state of Washington, and wildlife biologists -- with as many as 70 volunteers helping out -- are working to make sure the population continues to thrive.

The frog, a Pacific Northwest native, is listed as endangered in Washington, and is proposed for listing as an endangered species at the federal level as well.

Harold Cole Jr., a U.S. Fish & Wildlife Service employee and manager of the wildlife refuge, said the refuge has been working on a variety of projects in recent years that will help the frogs, which grow to about three or four inches long.

Swales have been cut in certain areas, which helps keep water in channels until frog eggs hatch and the tadpoles mature. Without the water, the eggs and tadpoles would dry up and die.

Marc Hayes, an Olympia resident and a research scientist with the Washington Department of Fish & Wildlife, is leading the volunteer effort, and setting a selfless example: He takes a month off from his WDFW job every year to run the surveys in Glenwood.

"This is one of the rarest amphibians in the Western United States," said Hayes, who added that the frog is now extinct in California and in the floor of Oregon's Willamette Valley.

To track the frogs' numbers, volunteers walk along at the edge of the lake bed and count and flag the egg masses.

The egg mass surveys, which generally take place from early March to late March, began on an annual basis at Conboy Lake in 1995. Since 1998, the data has been entered into computers to track how the frog's distribution changes.

Cole said volunteers have come from as far away as Texas, and he praised the efforts and dedication of those helping with the research.

"It's no fun wading in shallow water all day looking for something," he said.

According to Joe Engler, a biologist with the U.S. Fish & Wildlife Service, each egg mass has about 600 eggs in it.

"There are four places in the state where these frogs live, and this is by far the largest population," said Engler, who lives in Ridgefield. "There is a population in Trout Lake, and two populations by Olympia."

"We had a drought or two (in the 1990s) and the populations dropped way down," Cole said.

In recent years, however, the frogs' numbers have been coming back up significantly in Glenwood, and Cole believes the effort to keep water in pools and channels has made the difference.

"We hold some water to maintain habitat. This is a cooperative effort with the local landowners," Cole said.

Cole explained that what is good for the frog is also good for the neighboring farmers and ranchers.

"Projects like these helps the landowners with hay and forage, and helps us with frogs and eagles and elk," Cole said. "Conboy Lake is one body of water, but it requires cooperation. If the water goes away, they don't get any hay and we don't get any frogs. It has been mutually beneficial. Not everyone agrees, of course. Some think biologists ought to get a real job."

In a brochure about the refuge, the presence of the frogs in such large numbers near Glenwood is explained this way: "Like many frogs, the Oregon spotted frog needs a permanent water source -- lakes, ponds, or slow moving streams. In addition, these frogs must have emergent wetlands, which are shallow pockets of water that occur in adjacent flood zones," read an excerpt. "Most of these shallow floodplain pools were drained, diked, and filled to accommodate people. However, drainage efforts on Conboy Lake were not entirely successful. Rain and snowmelt overflowed drainage ditch banks even in settlement days, so frog habitat persisted."

In a rarity, the spotted frogs in Conboy Lake have coexisted with the larger and more aggressive bullfrog, an introduced species that has "out-competed" native frogs. The bullfrogs' predation of the smaller spotted frogs is believed to have significantly contributed to the disappearance of the native frogs from a large part of its former range.

Using information gleaned from research at Conboy Lake, biologists hope to find clues that could help the spotted frogs coexist with bullfrogs in other locations as well.

"This is the only system where bullfrogs and spotted frogs have coexisted for a long time -- 60 years," Hayes said. "Why is that?"

The Conboy Lake Wildlife Refuge was created in 1964, and now totals about 6,200 acres.


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