The Ripple of Effect of Climate Change: A look at how climate change and human impacts are impacting fish in New York lakes and streams

In some regards, the quality of New York’s lakes and streams has improved since the 1970s, according to Trevor J. Krabbenhoft, PhD, a fish biologist at the University at Buffalo. The enactment of the Clean Water Act formalized a system for discharging pollutants into the water.

But new challenges have arisen.

“Now we’re dealing with microplastics in the environment and other types of chemicals,” Krabbenhoft said. “There are multiple stressors that fish are facing, including human impacts, invasive species, and climate change.”

Microplastics, algal blooms, hazardous toxins, and habitat destruction, including dams and deforestation, are a few examples he offers. According to the New York State Department of Environmental Conservation (NYSDEC) winter temperatures are increasing faster than other seasons.

As a result, the traditionally cold-water lakes and streams are heating up. In addition to the environmental implications, the impacts on the fish populations pose an economic threat to the communities that rely on recreational and commercial fishing activities.

Collectively, those activities represent $7 billion and 750,000 jobs across all five Great Lakes—two of which share coastlines with New York. And that doesn’t account for the Finger Lakes or Adirondacks regions, both of which rely on fishing-related industries.

Krabbenhoft co-curates the Fish and Climate Change Database (FiCli), which is a repository of scientific articles on how climate change impacts fish. Based on the literature, he says rising temperatures are contributing to:

  • Changes in the distribution of fish populations. Fish are moving farther north or to higher elevations to find colder waters, while inland fish seek out deeper, colder areas within a lake.
  • Shifts in seasonal timing related to migration and spawning.
  • Changes to the species found and/or the abundance of specific species in a lake or stream.
  • Shifts in offspring population growth rates.
  • Changes in the genetics of fish populations as some species evolve to become more tolerant of warmer temperatures.

“I think they [fish] are a critical part of the food web and how nutrients flow through the Great Lakes,” he said. “Those dynamics are really important not just for what’s happening inside the lakes but also the surrounding terrestrial areas. A lot of birds feed on fish populations, so it’s all connected.”