Just when you thought it was safe to go back in the water.

Three-year-old Riley Chatman was all sandy from playing on the beach at Lone Ranch last week, so her father, Quinn, told her to rinse off in one of the freshwater creeks that run from the land to the ocean along the Oregon coast.

The Brookings girl laid down in a pool andndash; and promptly got out, covered in tiny, clear, big-eyed andhellip; bugs.

"Daddy, they're eating me! she screamed.

"It was a beautiful afternoon, you take the kids to the beach, and it turns into the beginning of a horror story," said Joanne Wiley-Apicello, Riley's grandmother. "This was a scary situation for her."

The little girl suffered about a dozen bites from just a few of the thousands of creatures Quinn and his wife, Jacquelyn, said they saw in the pool of water. He described them as being to andfrac14; inch long, leech-like, clear, segmented like a pill bug and with "really big eyes."

They brought a jar of the little bugs to the Harris Beach State Park office.

After three days of analysis, biologists on the East Coast, West Coast andndash; even Panama andndash; determined the critters are one of some 10,000 members of the isopod species Excirolana.

An isopod is in the crustacean family, but Excirolanas look like tiny slugs or leeches.

The species is native to the West Coast, and scavenges on debris in brackish intertidal pools.

And for whatever reason, said Harris Beach State Park interpretive ranger Angela Stewart, the Excirolana population is exploding this year, from Half Moon Bay to British Columbia. Riley apparently sat in a pool with a high concentration of the critters.

"It's kind of like a detective story," Stewart said. "It's like 'Who killed Colonel Mustard in the parlor?' When you get into critters that look a lot alike, we want to make sure they're (identified) right."

The Chatmans took their daughter to Curry Medical Center in Brookings, where doctors told them the bites were likely from sand fleas or baby crabs.

"Why would a baby crab suck my daughter's blood?" Jacquelyn said. "And everyone keeps telling us it's sand fleas, but we caught some and they look nothing like it."

But Excirolana are native to the area, Stewart said, adding that a similar incident occurred in Sunset Bay near Coos Bay two years ago. They're scavengers, and can bite andndash; and little Riley, Stewart said, merely sat in the wrong puddle at the wrong time.

"Very few crustaceans will actually bite you, but this nasty little creature is definitely one of them," wrote Dave Cowles, a biologist at Walla Walla University in Washington. "Barefoot waders in an area with Excirolana find that the animals quickly swim toward and swarm over your bare feet, biting them so hard that blood will be flowing within moments. Since the animals are so small, the bites are tiny, but painful like a pinprick, and they're often present in swarms of thousands."

That's pretty much how Quinn described the experience.

Stewart's glad the isopods are native to the area and aren't seriously harmful to people.

"It's natural," Stewart. "It lives here; it's part of our environment. It may die down as winter comes, but it's a natural thing."

And Riley is doing fine, Jacqueline said.

Beachcombers don't need to do anything special while out enjoying the Labor Day weekend, except examine pools before stepping in them.

"It's just part of the season," Stewart said. "It's been a wonderful year for salmon; it's been a wonderful year for the isopod. The isopod's having a very happy year."