NEWPORT — It’s not often that a high school science project ends with the entire class covered in mud, but for the Lebanon High School advanced placement biology class, Tuesday’s exploration of parasitic isopods ended in a lot of gloriously squishy fun.

Laura Saxe-O’Brien’s students spent the morning on the mudflats of Yaquina Bay, just beyond the Hatfield Marine Science Center, as they dug for shrimp and helped Oregon State University scientists unravel the mysteries of the sex life of bloodsucking parasites.

OSU associate research professor John Chapman and Brett Dumbauld, a U.S. Department of Agriculture ecologist and OSU researcher, have been studying the effects of parasites on two kinds of shrimp found right outside the doors of their offices at the Hatfield Marine Science Center — mud shrimp and ghost shrimp.

Dumbauld is interested in finding ways of controlling shrimp populations that are threatening oyster farming areas, especially in Washington, where pesticide use on the shrimp has recently been phased out. Chapman is interested in a new type of parasite that has recently begun attacking mud shrimp in Yaquina Bay and appears to be affecting a wide part of the shrimp population.

Tuesday morning, the Lebanon students were helping Chapman and Dumbauld gather and sort ghost shrimp, hoping to find the .5 percent of the ghost shrimp population infested with a parasitic isopod native to the area. Not a lot is known about the hermaphroditic isopods, especially their complicated sex life, and the students were hoping to gather information about the isopods and perhaps add to research that might expand knowledge about their reproductive cycles.

“The ones we’re working on now are in many respects the good guys,” Chapman explained as he gathered equipment in preparation for the hike down to the mudflats. “They’re a sand shrimp that’s native and have a parasite that’s native.”

The students followed Chapman and Dumbauld down the hill to the mudflats, where they quickly realized that even rubber boots weren’t enough to protect them from the deep, sandy mud. All too soon, students were falling over into the mud, including Megan Vorderstrasse and Megan Hainz, who were attempting to pull a submerged bucket out of the mud when the handle broke and sent them both crashing.

Ten of the 13 students took their AP science test on May 8, and since then their teacher has been focusing on fun projects that relate to what they’re learning and get them away from textbooks and into real-life experiments. The Newport trip was an especially exciting opportunity to learn about

university-level research and data analysis.

“Here you have a group of really detail-oriented kids that are all going to go to good colleges,” Saxe-O’Brien said, “so they’re getting a start on that.”

First, the students trekked out to find mud shrimp, a hand-sized shrimp with intimidating pinchers that lives deep in the mudflats. Those shrimp have recently been aggressively attacked by a non-native isopod that might have arrived from Asia aboard a ship and is now threatening the mud shrimp population.

“If we lift this carapace up, you can see the orange color there,” Chapman said, holding up a large male mud shrimp and showing the students where the parasite was located. “The isopod is a female, and she’s upside down and backwards. And that’s her tummy facing up this way, and her mouth is attached to the carapace there.”

After the easy-to-spot parasites living inside the big mud shrimp, sorting through the diminutive ghost shrimp to find relatively rare parasites wasn’t easy, but the students were eager to help, getting on their hands and knees in the mud to search out shrimp as Dumbauld pumped water into the mudflat to push the shrimp to the surface.

Four students sorted the shrimp at a nearby table, trying to find the few shrimp infested with isopods.

“We’re looking for a big lump on the side which could be a parasite, a little isopod, right in here,” Megan Vorderstrasse said, holding up a small, wriggling shrimp. So far, of the hundreds of shrimp they’d sorted, only one appeared to have been infested.

For the students, the trip to the coast was a welcome break from classroom work.

“Now that the AP tests are over, we’ve been doing a lot of hands-on stuff,” said Claire Nauman.

“This is the first field trip I’ve been on in high school,” Megan Hainz said.

“This is the first field trip I’ve been on since the fifth grade,” added Linda Loehr.

Once the students were done catching and sorting shrimp, they were ready to head back to Chapman’s lab and take a closer look at what they’d found. On the way, they were learning lessons of biology, science and simple life skills.

“If you get stuck in a mudflat and die,” joked Chapman, “you deserve it.”