WARRENTON - With their destination - a small wooden nest box - in sight, Astoria High School freshmen Josh Crowder and James Strecker and mentor Emily Brunner left the terra firma of the dike east of the Astoria Regional Airport and stepped into the smelly, dark mud.
Their boots sank in as the group walked single file through a mucky stretch, then crunched over dried-out cattails to reach nest box No. 24.
Crowder put his hand over the opening, pulled out a nail and lifted the side of the box to reveal a nest.
"It seems to be empty at the moment, no eggs," he observed. "The nest consists of feathers and grass" - typical building materials of a sparrow, he concluded.
The status of nest box No. 24 was recorded, and became part of nine years of data that has been collected by Astoria High School students on the Astoria Airport Mitigation Bank. Every year since 1998, students have been coming out to the wetland to take measurements of the area's flora, fauna and water quality.
"When I came here ... I was looking for a way to get kids outdoors and do real science," said Lee Cain, walking between groups of student scientists Thursday morning, taking pictures and making sure the they were on the right track.
He found out that the area by the airport is a mitigation bank wetland, constructed to compensate for Warrenton development. While scientists from the Oregon Department of State Lands and Oregon State University monitored the wetland's project for five years, by the late '90s no one was checking up on its health. So the high schoolers took on the monitoring job.
On Thursday and Friday last week, the Integrated Science classes were divided up into groups of two or three students, who went with mentors to examine different aspects of the wetlands.
Three set out with Todd Cullison of the Columbia River Estuary Study Taskforce to check on the abundance of red-legged frogs, Pacific tree frogs and bullfrogs as well as other amphibians like salamanders. They walked in a zig-zag pattern, with eyes on the ground, dodging willows and other obstacles.
"Just keep looking for frog movement," Cullison advised, as it started to sprinkle. At the end of the first survey, a critter was spotted.
"Victory, we saw one tree frog," Cullison said.
Another group, led by Astoria High School science teacher Allan Garvin, was measuring the water quality in a small stream nearby. Leona Russell held a small container of water, adding drops of a chemical solution one by one until the liquid turned pale yellow, adding eight drops of a starch solution to turn it blue, then adding more of the first solution until it became clear. The number of drops allowed her to calculate the amount of dissolved oxygen in the stream.
"How did they figure that out, by the way," she asked, adding that she wants to measure dissolved oxygen again: "That was fun."
Others are taking a survey of plants - stopping every five meters along a 75 meter transect to record the composition and height of the vegetation.
"How much tule is there?" Nicole Jones asked, reading down the checklist of plants. She looked up: "Whoa, there's a lot."
Up on drier land, a group led by Mike Patterson was listening and looking for birds at different stations in the wetland area, and finished by checking mist nets Patterson had set up. The first net had a vocal inhabitant - a Bewick's wren, which makes a distinctive cry when caught, Patterson said.
A fox sparrow and a pair of black-capped chickadees had tangled up in the second net. As students from other groups started gathering around, Patterson measured, weighed and tagged the small birds, handing them to students to release them.
Wetland monitoring wouldn't be complete without a fish survey, and two students were checking traps made of two-liter plastic bottles for three-spined sticklebacks, measuring them, checking to see if they were spawning and looking at the plate's on the fish's side to record the morph type.
The students will take the data they collect during the fieldtrips back to the classroom, analyze it and give a Power Point presentation to their fellow students. Over the years, they've found that most of the wetland, designed to be tidal, isn't really influenced by the tides, Cain said.
But still, he said, "It seems to be pretty vibrant, pretty alive." And next year, a new class of freshmen will be on site to measure more of its changes.