Artificial Fish Habitat or Fish Attractors: Which Do Fish Need and Why?

​Artificial Fish Habitat or Fish Attractors: Which Do The Fish Need and Why?  First of its kind comparison of artificial fish attractors and artificial fish habitat, explaining what works best for fish reproduction, protection and sustainability of fisheries.


Newly placed, this Fishiding High Rise model towers 12 feet off the lake floor and will soon become a haven for fish in lakes where natural cover is at a premium.  (C)Eric Engbretson Photo

Fish Sticks-The Habitat Management Tool That's Giving Wisconsin Lakes A Make-Over

 

Fish Sticks are assembled on lake ice over the winter. (DNR Photo)

In pre-settlement times, the near shore areas of all of Wisconsin’s lakes were filled with vast amounts of fallen trees.  Due to natural decay and storms that toppled large trees into lakes, our waters contained impressive amounts of timber that provided important habitat for fish and other species.  Today, those natural shorelines and their abundance of downed trees can only be found in a few places.  Lakes like those in Michigan’s undisturbed Sylvania Wilderness Area for example, give us a glimpse of the way all our lakes looked at one time.

As Wisconsin was settled and lakes were developed, shoreline trees were removed to make swimming beaches or to create an “uncluttered” look.  Large trees still growing along the shores were cut down to provide vistas of the lake for home owners to gaze at from their cottage windows.  In a short period of time, most of the wood on Wisconsin’s lakes was gone, eliminating a critical habitat element important to a wide variety of animals who made their homes in or near the lakes.

Today, we recognize the damage we’ve done by removing trees and interrupting the eons old process that replenished our lakes with a constant source of wood.  While it may take hundreds of years to restore our lakes to begin to resemble their original state, one innovative idea is jump-starting the process.  Referred to as “Fish Sticks”, it’s a way to move wood back to our lakes that’s been lost.  Fish sticks were made popular in Wisconsin by Bayfield County Fisheries Biologist Scott Toshner.  He’s worked on more than twenty fish sticks projects in the past four years.  "People tend to clean up their shorelines and remove fallen trees," said Toshner. "Sometimes the trees never get the chance to naturally fall into the water because lawns have taken over eliminating trees, shrubs, and ground cover. Fortunately, some northern Wisconsin communities are taking action to turn back the clock and restore the habitat on which fish, frogs, turtles, bugs, songbirds, ducks, and other critters thrive. Not only that, but they're good for water quality and shoreline protection, too."

Last year, a similar project, called “tree-drops” began on Florence County’s Lake Emily.  Tree drops are helpful but differ in that they usually involve single trees.  While their impact is important, a single tree can’t do the same job as multiple fish sticks.  Dr. Mike Bozek, formally of UW-Stevens Point, has studied this distinction.  “Submerged trees located closer to other submerged trees result in greater numbers and diversity of fish compared to individual trees. Larger numbers of submerged trees create a mosaic of habitats over greater shoreline areas than single trees do. This underscores the importance of riparian areas. We need to manage entire riparian areas and develop complex littoral zone habitats, not just individual trees.” 

As science has begun to better understand the importance of woody habitat in lakes, one type of habitat enhancement that’s been used on Wisconsin’s lakes for generations is on the way out.  In recent years, Fish cribs, have fallen out of favor with fish managers.  New studies show it’s a poor substitute for more natural and legitimate types of fish habitat like fish sticks.   "With the fish cribs, the one thing you kind of miss with them is the link between the near shore area where a lot of these fish spawn and spend their lives as juveniles ... [With fish sticks] the wood in this near shore area may be a missing link in terms of habitat in some of these lakes," Toshner said. 

To further illustrate the difference between single tree drops and fish sticks complexes, we can look to Bony Lake in Bayfield County.  This 191 acre lake was one of the first to employ fish sticks.  To date, more than 400 trees have been added to the lake, and they’re not done yet.  This may seem like a whole lot of wood, but in truth, it’s only a fraction of what the lake would have contained had shoreline property not been radically altered by development. Toshner hopes that as users of lakes, we’ll redefine our idea of what beauty is and discard our desire to create white sandy beaches and instead embrace the wild, unorganized, and natural look of shorelines comprised of fallen trees.  “Fish sticks projects are paying off in northern Wisconsin lakes by providing critical habitat for fish and insects, birds, turtles and frogs," says Toshner. “Beaches are really ecological deserts which don’t support any habitat or sustain any life”. 

A new streamlined permit available from the state and an easy step-by-step guide for fish sticks is now available from the Wisconsin Department of Natural Resources.  This will help lake associations or individuals get started with their own lake improvement projects that incorporate fish sticks.  Scott Toshner is excited about the changing landscapes of our lakes and is optimistic about how as stewards we’ll make better decisions in the future.  "If people can see that trees in the near shore area are a valuable resource, they're less likely to remove a tree that might fall in along their own shoreline."

Creating Great Fish Habitat

A fallen pine tree creates shelter for schools of small bluegill which attract
largemouth bass and other game fish.  (c) Eric Engbretson

When I speak to various organizations or lake associations, one of the questions most often asked is "How can we create good fish habitat?"  One way to do that is actually easier than you might imagine.  One of the best things we can do is... "nothing". 

Every time there's a storm and trees get blown down in our yards, we respond right away by picking up the brush and debris and quickly cutting up the fallen trees and branches with chainsaws to restore our yards to their pre-storm state.  This is fine to do in your yard, but if you have lakefront property, it's one of the worse things you can do near the water.  Trees, large and small that fall onto our beaches or into our lakes due to storms or natural decay are one of the most valuable habitat elements for fish, birds, reptiles and amphibians.  We're tempted to remove the trees to return our shorelines to a state that resembles Waikiki Beach, but when we do, we're robbing the lake and it's inhabitants are critical elements that enhance fish populations.    

Even small trees or branches in shallow water provide critical habitat elements
for a wide variety of fish. (c) Eric Engbretson

I visit many lakes that are ringed with homes and bordered by forest, but in a great many lakes, there’s scarcely any downed trees in the water. Since trees must go down from time to time in storms, falling into the water, I can only assume that lakefront property owners quickly remove them.  This should be avoided because wood and trees that have fallen in the water are a critical habitat element important to a variety of aquatic and terrestrial life. I strongly encourage all lakefront property owners to keep fallen trees in the lake instead of removing them. If they absolutely impede navigation, they should be moved, but not removed.

Trees that fall into lakes are magnets for crappie and
other panfish. (c) Eric Engbretson

I have thousands of underwater pictures that show what great habitat fallen trees provide and how fish utilize them.  Trees of all sizes provide important shade, cover for minnows and juvenile fish, ambush areas for game fish, and protection that's important for successful spawning.  They attract aquatic insects, crayfish and other food sources important to fish.  Studies done in northern Wisconsin show that lakes without coarse woody habitat show declines in fish growth rates and the amount of fish a lake can support. 

So, one of the best ways to actually create terrific fish habitat in our lakes is simply not to destroy or remove the habitat that is naturally made by nature when trees are blown down in storms.