Jessi DeMartini stood in the shallows of the West Branch of the DuPage River, explaining the plan. To her left, Joe Limpers kept a cooler of 2,000 plain pocketbook mussels from floating off.
‘‘Our vision is to keep common species going in an urban stream,’’ said DeMartini, the coordinator of the aquatic research center for the Forest Preserve District of DuPage County.
There were double-pronged actions June 24 by volunteers from the Illinois Smallmouth Alliance under the direction of DeMartini and Limpers, an aquatic tech.
One prong was planting 10 flats of water-willow, three flats of sweet flag and a flat of lizard’s tail. Two patches of water-willow from plantings several years ago grew well near the Mack Road dog area at Blackwell Forest Preserve.
DeMartini calls those plants ‘‘river warriors.’’
‘‘Lots can’t handle urban waterways; these can,’’ she said.
Those ‘‘warriors’’ include sweet flag, blue flag iris, water-willow, softstem bulrush, other bulrushes, lake sedge, golf-course grass (bentgrass) and, lately, indigo bush.
DeMartini has been around long enough to see the restoration of the DuPage watershed take root — literally.
What she calls ‘‘my big fat mussel restoration’’ is the latest example.
That morning, 2,000 1œ-year-old plain pocketbooks were going into 20 quadrants near Mack Road. They were part of the 9,000 mussels raised at the Urban Stream Research Center in Warrenville that DeMartini hopes to release this year at 11 sites along 13 miles of the West Branch and Kress Creek, a tributary. Fatmucket mussels, which are rarer in the West Branch, will be in the next round of releases.
This is a new project, so each tiny mussel is tagged in gluing parties with glitter or blue dots.
‘‘There were fans and lots of doors open,’’ DeMartini said. ‘‘It was like the 60s.’’
Forty mussels (8 percent) this time had PIT tags glued on. PIT tags allow them to come along later with an underwater antenna and tell where those mussels are.
This is a long-term project because it takes five years for them to propagate. In the wild, the mussels attach larvae to host fish, such as smallmouth bass.
‘‘What they do in the wild, we do in the lab,’ DeMartini said.
And much better. About 1 percent of juveniles in the wild reach adulthood; in the lab, it is 25 percent.
Mussels matter in restoration for more than diversity. Adult mussels can filter 18 gallons of water a day.
‘‘Repopulation could filter 20 percent of the stream daily,’’ DeMartini said.
She and Limpers directed us on proper placement. There were 20 (4 x 5) numbered stakes of a meter square. Limpers doled out numbered bags of mussels to match each stake. Each bag included two PIT-tagged mussels to be spaced upstream and downstream of the stake.
The mussels were pushed, one at a time, about three-fourths into the bottom — ‘‘pointed side up, foot down’’ — with the edge facing upstream.
Max Kasick, a sophomore at Reavis, started with Stake 1. It was harder to figure out those instructions than it might seem, but you got the hang of it after a while.
With a half-dozen of us, placement went quickly.
When we finished, DeMartini said, ‘‘It’s another piece of aquatic conservation.’’
Follow me on Twitter @BowmanOutside.