Relocating Fish to a New Spring Brook

A Blog Story About Nature in Our DuPage Forest Preserves

Relocating Fish to a New Spring Brook

Posted by Scott Meister | 9/14/20 11:50 AM

Restoration of Spring Brook as it flows through Blackwell Forest Preserve includes building a new stream channel and removing a dam to provide better habitat and a gentler slope to allow fish to swim upstream.

In late August 2020, construction of the new channel was completed and water flow was diverted into the new channel. This left the old channel — and any fish in it — isolated. As the remaining water in old channel began to recede, Forest Preserve District ecologists scoured the old stream remnants in search of fish for three days in early September.

fish-relocate-2

To do this, staff used a backpack electrofisher to send a small electric current into the water and temporarily stun the fish. At that moment, fish briefly float to the surface and can be captured with nets. Electrofishing does not harm fish and is a common practice to conduct fish surveys.

Over three days, staff collected 1,159 fish of 22 species from an approximately 1,200-foot stretch of the former stream (crayfish and freshwater mussels were also collected). These fish were then relocated into the newly constructed stream to live their lives in better habitat that included oxygen-rich water, a diversity of aquatic plants, a mix of deep and shallow water, and better substrate for spawning. A complete list of the translocated fish is below.

spring-brook-fish

Previous fish surveys in the upper reaches of Spring Brook at St. James Farm Forest Preserve indicated there were only 8 species of fish in the waterway. Restoration of Spring Brook and removal of the dam provides the opportunity for a greater diversity of fish to freely move upstream and colonize areas where they were previously restricted.

Species Count
Green Sunfish 451
Bluegill  166
Yellow Bullhead  125
Creek Chub  77
Bluntnose Minnow  67
Western Mosquito Fish  61
Blackstripe Topminnow  43
Largemouth Bass  39
Central Stoneroller  36
Sand Shiner  21
Johnny Darter  20
Smallmouth Bass 
18
White Sucker  13
Stonecat  
8
Gizzard Shad  5
Pumpkinseed  2
Black Bullhead 2
Bluegill/Green Sunfish Hybrid  1
Golden Shiner 1
Spotfin Shiner  1
Black Crappie  1
Redear Sunfish  1
Total 1,159

fish-relocate

 

 

Topics: Insider, Locations, Wildlife, Conservation, Nature

Written by Scott Meister

Scott Meister is manager of Natural Resources for the Forest Preserve District of DuPage County and has been on staff since 2002. Scott has a passion for wildlife and began his career as an ecologist. He continues to participate in programs that restore habitat and promote wildlife diversity in DuPage County.