The Great Lakes are feeling climate impacts, too. Here’s how.

Warmer waters = animals on the move

Wading into warmer water during a summer swim is a nice perk for people, but not so nice for the fish and other wildlife that call the lakes home. Since 1995, average surface water temperatures have increased slightly for each of the Great Lakes, according to EPA data. Those increases have mostly been driven by warming air temperatures during the spring and summer months.

Here’s why it matters: You may be getting fewer bites on your fishing line. Changes in water temperatures have disrupted the geographical ranges of fishes over the last several decades. For example, game fish like bluegill, smallmouth bass, largemouth bass and brown bullhead have moved “poleward,” extending their ranges north. Changes in individual populations like this can upset entire ecosystem structures with new species interactions, changes in the food web and more. This threatens the livelihoods of animals and people who rely on them and impacts recreation. Studies show that invasive species also have more opportunities to invade Great Lakes habitats because the defense of natural communities are reduced in an environment stressed by climate change.

Less ice = less water

Northerners and Midwesterners appreciate any reprieve from the normally frigid winters. But milder winters are causing lake ice to form later than usual. This increases the amount of time that water can evaporate into the atmosphere, lowering the Great Lakes water levels. The Great Lakes have lost more than 70% of their total winter ice cover over the past 50 years, impacting fish habitat and ecosystem health.

Here’s why it matters: Beloved Great Lakes beaches could be disappearing. Less ice, coupled with more frequent and intense storms, leaves shores vulnerable to erosion, flooding and other impacts on aquatic life that rely on shoreline ecosystems. Lower water levels can also affect water supplies and the usability of infrastructure such as docks and piers. EPA research said lower water levels in the Great Lakes forced ships to reduce their cargo tonnage, which increased shipping costs for the consumer.

Erratic weather patterns

Get used to wearing shorts one day and a parka the next. Unlike global ocean levels, which are projected to continue rising about an eighth of an inch per year, we can expect to see more erratic patterns in Great Lakes water levels overall due to an increase in extreme weather patterns.

Here’s why it matters: You should be prepared for any weather emergency. Erratic weather can cause higher winds, which then produce swells and waves that can threaten homes and businesses on the shores of the Great Lakes and further inland. Climate change can cause heat waves and drought, heavy downpours, tornadoes and more.

The domino effect

Like a row of dominos, it seems that one impact tips into the next into a long string of climate woes for the Great Lakes and surrounding regions. While these changes may seem daunting, Shedd, along with you and the greater Surge community, is committed to mobilizing to take action to combat the effects of climate change. Shedd researchers are working to help us better understand how animals respond to a changing climate. Shedd Aquarium Action Days allow us the opportunity to restore local woodland and shoreline habitats. And we continuously advocate for science-based policies across local, national and global governments that will build a more sustainable future for us all.