More than 20 sixth-graders giggled, squirmed with excitement and waved goodbye Tuesday morning as the fish they had raised from eggs set off on their first voyage down the Mokelumne River.
For 15 years, John Muir Elementary School teacher Beth Largen and her classes have nurtured groups of salmon eggs, watching them emerge from eggs to become fry, or young salmon.
The sixth-graders hope that their two-inch long, dark gray fish will grow up to be full-grown salmon that will eventually come back to spawn in the same river where they let them go.
The project coincides with the classes' sixth-grade science curriculum and, Largen said, melds fun, hands-on experiences with concrete scientific knowledge.
It also offered the students a glimpse into the deteriorating salmon population in the Mokelumne River.
This year, only 1,000 salmon returned to the river to spawn. That's down from the regular 4,000 to 6,000, said Shazana Gardner, an office technician from the Department of Fish and Game who led Largen's class on a tour of the Mokelumne River Fish Hatchery.
Gardner said there are several theories out there, but she doesn't know why so few salmon returned to the river this year.
"A day like this is pretty rewarding for me because I get to see the learning come to life," Largen said. "It makes it real for them."
Largen, who received a license to raise the salmon from the state Department of Fish and Game, obtained the eggs from the hatchery on Dec. 13.
Since then, she and her students have kept their scaled friends in a 10-gallon tank inside a regular-sized refrigerator - young salmon need to stay cold in order to develop - stopping by each day to monitor their progress.
In addition to studying the fish, Largen's class also studied rivers - the erosive power of fresh water, the bugs and insects that inhabit them and the electric power they can provide through dams.
The Salmonid Restoration Federation will host its 26th annual
restoration conference in Lodi from March 5 to 8.
Attendees can participate in tours of the Tuolumne and Stanislaus river restoration projects, fish-friendly vineyards and the Cosumnes River Preserve.
Several lectures and workshops will also focus on salmon recovery, restoration, sustainable agriculture and watershed management.
"In light of the recent San Joaquin settlement and the plight of wild salmon in California, it is more important than ever for scientists and restorationists to learn about habitat restoration techniques to recover native salmon and steelhead," said Dana Stolzman, executive director of the Salmonid Restoration Federation.
The Salmonid Restoration Federation is a nonprofit organization that works to protect and restore salmon, steelhead and trout populations.
Other highlights of the conference include films from the Wild and Scenic Environmental Film Festival.
One film, "Tales of the San Joaquin," tells the story of the San Joaquin River. Christopher Beaver, who made the film, followed the river from its source to the San Francisco Bay, documenting its many abusers and the salmon that used to spawn in it.
Films will be shown at the Performing Arts Theater at Hutchins Street Square on March 6 from 6:45 p.m. to 10 p.m. Tickets cost $12 for adults and $8 for adults and senior citizens.
For more information visit http://www.calsalmon.org.
- News-Sentinel staff.
• Salmon like to lay their eggs on the rocks and gravel of backwater pools instead of in the mud. This method protects the eggs from predators while at the same time allowing water to flow over them.
• Salmon eggs need constantly flowing water to provide them with oxygen.
• The female salmon makes a nest to lay her eggs, then signals the male salmon to join her. She lays her eggs while the male salmon fertilizes them. The whole process takes about 15 seconds.
• The largest salmon ever recorded weighed 115 pounds and was caught in Alaska.
• The Chinook Salmon is considered an endangered fish.
• The highest number of salmon ever to spawn at the Mokelumne River Fish Hatchery was 14,000.
This year only 1,000 salmon came to spawn. That's a 25-year low for the hatchery.
• Salmon track their way back to their home river by their sense of smell. Salmon can smell 10 times better than dogs.
• Female salmon hold between 4,000 and 8,000 eggs. All of those eggs can be fertilized with only one teaspoon of male salmon sperm.
- Shazana Gardner, office technician for the Department of Fish and Game.
By weaving what they've learned with an activity, Largen believes her students will not only retain more of what they absorb, but enjoy it as well.
"If your curriculum is engaging, your kids will do it," Largen said.
The kids just think it's fun.
Darting from one backwater pool to the next, the students trapped water bugs with plastic magnifying boxes while their fry sat in a bucket acclimating to the crisp Mokelumne water.
One student, holding a glass slide, pranced back to the picnic table to use the class' field microscope.
"What did you find?" asked Largen.
"A piece of grass," the girl replied.
On top of learning the hows and whys of the Mokelumne River and the fish that live in it, Largen has also helped develop a healthy respect for nature in each one of the children.
"Don't litter in the environment," she cautioned before sending the students out to collect bugs. "And try not to kill anything."
Though Largen expects the experience to be fun for her children, she hasn't shielded her students from the bleak reality that maybe one out of the 50 fish will make it back to the river to spawn.
"They know the odds," Largen said.
Pollution, predators, dams and sedimentation could all lead the fry to an early end.
In fact, several of the students asked Largen if they could keep the salmon, but Largen said the salmon need to enter their natural environment at an early age if they are to know to which river to return.
"I'm going to cry when my fish go bye-bye," said Dakayla Quarles, 13. "We raised them so good. Then they grew big. Then you have to let them go."