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Aquatic Ecosystems

Climate change will affect our aquatic ecosystems in Illinois as well. With earlier spring seasons, lake water surfaces will warm earlier. With higher air temperatures, the water will reach higher temperatures in the summer and cool more slowly in fall. Warmer water will likely result in the production of phytoplankton earlier in the year. Stratification of the water (the separation of a body of water into relatively distinct layers by density) may reduce the size of the crop. Stratification may reduce the amount of oxygen for bottom-dwelling bacteria, plants, and animals and could cause fish kills. Warmer water conditions will also favor warm-water species and change the species composition in lakes and rivers. As reported in the 2018 “Building Resiliency to Climate Change,” it may also increase harmful algae blooms (15). 

What has IDNR Been Doing?

Supporting native species is the main goal of the IDNR’s Division of Natural Heritage. Staff conduct novel research, design studies, and utilize existing data to answer conservation questions. As part of IWAP, the Streams Campaign enhances and protects native aquatic habitat and aquatic species throughout the state. It aims to implement effective aquatic conservation through monitoring and assessments, protection, water quality and flow management, connectivity efforts, and eradication of invasive species.

  • The Streams Campaign
  • The Aquatic Ecology Program 
  • IDNR Endangered Species Program
  • IL Endangered Species Protection Board
  • Biological Stream Ratings

Read More

Species Conservation
This IDNR webpage provides information about IDNR’s species conservation efforts. It includes information about IDNR’s Aquatic Ecology Program and endangered and threatened species. 

Educational Resources for Aquatic Topics
This collection of IDNR educational resources provides a wealth of information about aquatic topics. Resources include posters, lessons, resource trunks, coloring pages, educational resources and more.  See, for instance, their Aquatic Illinois Teaching Unit.

Biological Stream Ratings
This IDNR resource is a conservation program that classifies streams based on fish communities. The rating process also includes information on endangered and threatened species and mussel diversity.