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Any other July day, you'd expect to see 100 or more white pelicans dotting this 350-acre rural Stutsman County wetland, their large pouched bills unmistakably heavy with salamanders.

Today, only four birds are in attendance and sitting motionless, a testament to just how poor the fishing is here.

The birds, migrants that make up the largest North American breeding population at nearby Chase Lake National Wildlife Refuge, aren't the only ones who have noticed the skimpy pickings. Scientists have reported a dramatic die-off of tiger salamanders at this Cottonwood Lake Study Area wetland, identified simply as P11.

It's speculation at this time, but scientists believe the salamander crash is the result of a lethal iridiovirus first observed elsewhere in insects.

"There have been times (in 1996) when we'd get 150 to 200 pounds of salamanders in a trap and it would take two large human beings to drag it to shore," said Ned Euliss, research biologist with Northern Prairie Wildlife Research Center in Jamestown

	David Mushet, wildlife biologist with Northern Prairie Wildlife Research Center in Jamestown, returns an empty salamander trap to a wetland known simply as P11. The salamander population in this wetland in Stutsman County has crashed this summer, possibly because of a virus.

On July 13 when the three traps were checked at P11, they were empty.

"That's a first for here," Euliss said. "July is typically a big (salamander) sampling event..."

Typically, biologists are catching a lot of the newly hatched young.

"Normally, there are tens of thousands of salamanders in this wetland (at this time)," he said.

Today, you might be able to count this wetland's entire population on your fingers and toes.

In May, researchers first noticed a problem when some of the salamanders started turning up with discolored skin, said David Mushet, wildlife biologist with Northern Prairie.

"In June, we started finding dead ones in the traps," he said.

Scientists with the USGS Wildlife Health Center in Madison, Wis., are testing dead salamanders from Stutsman County and could determine sometime soon why the animals are losing their skin and dying.

"The lesions tend to start up behind the head...the skin just basically falls off," he said. "Their livers are also enlarged as well as their spleens, which is consistent to fighting off some kind of infection."

There is believed to be no link between the decline of the salamanders this summer and a population of frogs near Butte that plummeted last fall, Euliss said. The only common thread is that hundreds of individuals from both populations have died.

Officials with the Wildlife Health Center determined that the leopard frogs fell to a highly contagious chytrid fungus new to North Dakota.

If the cause of the salamander crash is indeed an iridiovirus, it's guessed that it will eventually run its course. Researchers are taking precautions by disinfecting their gear so as not to spread the mysterious salamander killer to other wetlands.

What's killing the animals is making the rounds, nonetheless. So far, scientists have determined problems in three of Cottonwood Lake's 17 wetlands.

"It's spreading...it's getting worse," Euliss said.

On the other hand, the die-off is worrisome because salamanders are an important food source for pelicans and other species, Euliss said.

"What is it going to do to the food chain? We don't know," Euliss said. "That's the big question."

Yet, on the other hand: "Even though we don't like to see it, large population die-offs are natural," Euliss said. "We see these populations go up and down. The animals that live on the prairie have explosive populations. Most of the animals in this part of the world are on a roller coaster."

This is not the first time salamander populations have dropped significantly at the Cottonwood Lake Study Area. Past die-offs, however, were tied to winterkill, or a shortage in what the amphibians eat—invertebrates—to stay alive.

Interestingly, scientists aren't seeing a bunch of dead salamanders just lying around. Euliss said those invertebrates, or amphipods, that the salamanders eat are now feeding of the dead amphibians.

"They're little scavengers," Euliss said of the amphipods.

The good news about the salamander die-off is the location. The Cottonwood Lake Study Area, about 40 miles northwest of Jamestown, is said to be one of the most intensively studied wetland complexes in the world. Scientists have been collecting biological data here since 1967 and looking into the underwater and terrestrial lives of salamanders for nearly a decade.

"Because it's so heavily studied, we may be able to determine down the road what triggered the outbreak," Euliss said.

Tiger salamanders are fascinating creatures. They grow to 10 to 11 inches in length and sport slimy, homely features only another amphibian could appreciate. In the wilds, they can live up to about 3 years of age.

This underwater-dwelling tiger salamander still has gills. It calls a fish tank at the Northern Prairie Wildlife Research Center in Jamestown home. Its counterparts living in the wilds in Stutsman County are dying at an alarming rate due to what scientists believe may be a lethal virus.

Salamanders, like those in P11, crawl from the wetland sometime in the fall and scout out rodent burrows in which to spend the winter. Then again, some animals never venture from the water and spend their lives there.

The latter happens when the young salamanders develop lungs, yet hang onto their gills, enabling them to live under water. This neotinic behavior, Euliss said, may be the result of the amount of food available when the animals come to the development crossroads when their gills stay or fade away.

Meaning: If the wetland is loaded with amphipods, then there may be no reason for the animal to lose its gills and wander up on land. But if pickings aren't as lush in the water, then maybe it becomes a necessity to be able to spend part of the time on land.

Those salamanders that live their lives under water tend to be larger than those that migrate between the wetland and the prairie. What's killing these animals is not discriminating, however. Both the big and small are dying.

"Disease is like anything else in nature," Euliss said. "It's one of those ugly things we have to deal with."

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