by Madelyn Anderson –Have you ever wondered what happens to a lake when the water rises? Aquatic plants, lake sediment, fish communities and more can be affected and, here at Hasler Lab, we’re uncovering how.
Last summer we introduced you to Cassie Ceballos, a PhD candidate investigating the ecological impacts of rising water levels at Fish Lake, one of the North Temperate Lakes Long-Term Ecological Research (NTL-LTER) sites.
Located just west of Lodi, Wisconsin, Fish Lake’s water level has risen nearly twenty feet since the 1970’s. Not surprisingly, its ecosystem has undergone drastic changes that can be felt at every level.
“There are so many questions surrounding this one changing thing,” said Ceballos. “Everything is connected.”
Her team, housed in Dr. Emily Stanley’s lab, hopes to build continuing knowledge on the effects of high water – a task made possible by the decades’ worth of data NTL-LTER has collected on the lake. This long-term data also allows researchers to see trends beyond year-to-year variability.
Last summer, Ceballos’s work began in the midst of a drought. This season, the team has been met with persistent rain.
“[Water] clarity is deeply affected by rising water and precipitation,” said Ceballos. “The contrasting weather patterns we’ve already experienced will be interesting. Fish Lake is noticeably more green.”
But water color isn’t the only thing they observe. Ceballos and Maddie Muller, her summer undergraduate field technician, are sampling five littoral sites – nearshore terrain that is now submerged in the lake’s rising water – and one deep site out in the middle of the lake each week.
As they work, their anchor often pulls up remnants of Fish Lake in lower-water times, carrying with it asphalt from underwater roads or branches of decomposing trees.
They are also bringing new data abroad that is slowly revealing the fate of different species in the lake.
“I’m interested in the biological communities facing high water: are they suffering or thriving?,” Ceballos asks. She’s learning that “some aquatic plants, like smartweed, take hold of the opportunity and make new habitats. Some fish species, which feed and nurse in littoral zones, are recovering. Coontail, a native species, has grown instead of milfoil (an invasive plant), but [the coontail] can form dense mats” and become a nuisance, she says.
Understanding these complicated dynamics requires a careful eye and repeated sampling. With recent storms and rain-soaked runoff leaching into Fish Lake, things can change weekly. But Ceballos keeps her eye on the data she’s collecting, especially the key species of plants that can help provide answers about what’s going on beneath the surface.
“Macrophytes (large aquatic plants) offer a first look at the ecological impacts of rising water,” said Ceballos. “They are surviving on the edge.”
As Ceballos continues to explore aquatic interactions between the chemical, geological, biological, and beyond, more answers will wash ashore but one thing is, so far, fairly certain – aquatic communities can persevere, even in the face of never-ending floods.
