The stat comes from Jeff Reutter, Director of Ohio State University's Stone Laboratory. He says the converse is true for Lake Superior. It holds 50% of the water, but just 2% of the fish.
It's a rough estimate, he says, but it gives you a good understanding of how each of the five Great Lakes have unique characteristics, which present unique challenges in managing these lakes.
As part of our series on how climate change is affecting the Great Lakes, Reutter spoke to us about how Lake Erie is especially vulnerable to temperature variations. It is the southernmost, and the shallowest of the five Great Lakes.
He also spoke about how, unlike the other four Great Lakes, Lake Erie is surrounded by agriculture and a more urbanized landscape.
You can listen to him speak about his "50 and 2 Rule" here:
Lake Erie has seen a resurgence in blooms of cyanobacteria (sometimes referred to as blue-green algae) over the last ten years. It was once a big problem in the 60s and 70s, and it has returned as a problem again.
You can see pictures of a bloom and read more about it here.
Sport fishery taking a hit
With a lake that is home to so many fish populations, you can imagine the importance of the sport fishery in Lake Erie.
Charter boat captains in the area have taken a big hit - especially after the 2011 bloom (see photo above).
Their customers don't want to fish in the blooms, so the captains have to burn a lot of gas to get out of them. For boats that average one mile per gallon, you can imagine how the cost adds up.
On our visit to Lake Erie, we also spoke with Paul Pacholski, the vice president of the Lake Erie Charter Boat Association.
In the late 1980s and early 1990s, Pacholski says there were once around 1,200 charter boat captains on Lake Erie. Today, he says, there are around 675.
Here he explains why he loves what he does, and how the return of cyanobacteria blooms on Lake Erie threaten that.
Clarification: An earlier version of this story referred to "algae blooms" in Lake Erie. These are really bacterial blooms (cyanobacteria) that look like algae. The copy has been clarified above.