Groton — Lucas Ranelli, 9, held a chunk of the tidal saltwater marsh off Bluff Point and squeezed as hard as he could.

"I thought it was really mushy. And it really smelled," said Lucas, of Niantic.

His observation was part of the Ocean Explorer Academy day camp, one of four programs Project Oceanology in Groton is running this summer, along with a fifth program in cooperation with Mystic Aquarium.

About 450 students from across southeastern Connecticut and elsewhere are enrolled in the marine science programs through August.

Lucas explored the marsh on Thursday with students from Groton, Salem, Oakdale, Old Lyme and other communities.

"For just a couple of minutes, we're going to quietly look around," instructor Abby O'Brien told the campers after they arrived by boat.

Listen, look and smell, she instructed.

The state's budget crisis affected one Project Oceanology program this summer: The Connecticut River Institute, a two-week, grant-funded program run out of Old Lyme, lost one of its sessions.

Jim McCauley, executive director of Project Oceanology, ran the first session of the camp, then had to cancel the second session.

He's awaiting word from the state about the next two sessions, he said.

The weeklong explorer academy took students to Pine Island, out into Long Island Sound, to Bushy Point beach at Bluff Point and to the saltwater marsh and to an area to observe near-shore fish.

"What I like about this camp is most ocean camps you learn about a lot of exotic animals, but at this camp you learn about the local animals," said Celia Nichols, 10, of Montville. "I like learning about things I can study that are right near me."

Hayden Tyler, 13, of Groton liked seeing how different a marsh is from other environments. 

"It's all, like, grass and mud, and a beach would be all sand," he said. "It's interesting."

Campers received a "passport" to fill out and get a stamp for each environment they visit.

"We're trying to show them a snapshot of everything that's available here, hoping they fall in love with it as much as we have," O'Brien said.

It can be challenging to get children to appreciate a marsh at first — it's muddy and occasionally smelly, she said.

But it's crucial to the health of other ecosystems.

Usually, campers love it by the end of the day, she said.

"People save what they love," O'Brien said. 

Students jumped on the marsh to hear it squish. O'Brien dug up a large spade of peat and handed it to the campers. 

If you squeeze hard enough, you can get water out sometimes, she said.

Lucas tried and got muddy. But if the chunk were closer to a tide pool, it would have been wet, he explained.

Then he and other students tested the water for measurements such as dissolved oxygen and salinity.

"They're our little masters of science," O'Brien said.

Nora Walker, 12, of Marlborough said she'd go to the camp again.

"But probably the overnight one. Because that one sounds really fun," she said.

d.straszheim@theday.com