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Why Fish Cribs Work and Why They Fail

Engbretson Underwater Photography

Why Fish Cribs Work and Why They Fail

This article by Eric is the most comprehensive list and overview of fish cribs and habitat

preferences utilized by most of the North American fish species I have ever come across.

His career spanning over 30 years in underwater fish photography has given him and now us,

a look beneath the waves to understand what he and his colleagues have been seeing for years.

In over four years of extensive study, I have not found anyone else who understands

fish behavior and has the photos to prove his findings like Eric. Groundbreaking

information never before available, will help us understand how to best construct,

place and revitalize new and existing fish cribs and why. Did you know fish preferred

to be able to swim under the crib, not to mention key points like density, height

and proximity to aquatic vegetation? More habitat articles at fishiding.com

Eric and I talk regularly about habitat, cribs and fishy stories surrounding this

underwater world which he is so familiar with. He has installed some of our

artificial habitat units in his own lake for long term monitoring as well as other

lakes in the area to see just how well they stack up. Although skeptical at first,

he has seen the aquatic growth, fry and predator fish utilizing our products and

find we meet most, if not all of his criteria for why our products work so well.

Sit back and read into the underwater world of Eric and his team as they share

their insight of how, why and where fish cribs work from the first hand account

of divers under the surface.

Take a look through his site and the thousands of images he has compiled

over his career under the water’s surface. This is only the start of fully

understanding and improving the fish cribs we install. The Fishiding pictures

he has taken and observed will only help us improve on how best to help our

fisheries. Throughout this diving season, Eric and his team will continue to dive

and document our cribs and others for all to enjoy and learn from. Preferred

crib color, fish abundance, water fertility/clarity and sunlight penetration are just

a few of the many unanswered questions we are beginning to understand with

Eric’s help. Watch for a new, taller model to come out soon!

 

Engbretson Underwater Photography


Why Fish Cribs Work and Why They Fail

By Eric Engbretson

 

When I encounter fish cribs in lakes where I scuba dive, I typically see one of two opposite things: cribs holding fish, and cribs attracting no fish at all. In years of first-hand underwater observation, I have noticed that the cribs with fish share certain characteristics. So do the cribs devoid of fish. I’ve concluded that there are two key aspects of cribs that succeed in drawing and holding impressive numbers of fish. Those two critical components are design and location. Let’s look at each one separately and see why some cribs succeed while other cribs fail.

Design:

Years ago, fish cribs usually shared a single design. They consisted of big logs lashed together to make a cube like a miniature log cabin without a roof. The interior was stuffed with brush or tree branches and they were weighed down with concrete, cinder blocks, or heavy rocks. Since these structures can be very large, heavy, and almost impossible to move, they’re built in the wintertime in northern states and left on the ice, where they sink into place in the spring when the ice starts to melt. The cribs are usually square but sometimes rectangular. They are typically four or five feet high and four to eight feet long.

Since the classic wooden log-cabin style is the most popular kind of fish crib, my observations and comments focus on these specific types of cribs and in particular on the best ways to make them as effective as possible.

By their very nature, most fish cribs have a distinctly limited lifespan. When they’re fresh and their interiors are tightly packed with brush and tree limbs, minnows and juvenile fish will flock their way. The thick cover provides shelter and a place to hide from predators. The smaller fish penetrate deep into the cribs. Panfish will congregate outside or squeeze their way in where they can. Larger predator fish, such as bass and northern pike, will hang around the perimeter, attracted by the throngs of fish concentrated in this area.

The interior material of thick brush or tree branches gives rise to a problem that is endemic to fish cribs. The material provides dense cover that small fish need, but over time it disintegrates, leaving only the cribs’ outside skeleton intact. The center portion remains basically empty. Without brush and branches, the cribs can no longer protect small fish from larger fish. And once the small fish–a source of food–disappear, the crib also loses its appeal to the game fish, which no longer gather around the crib to enjoy the all-you-can-eat buffet it once was. While these cribs might occasionally still draw a few larger fish for shade or cover, they lose their major attraction as a feeding center. Most people don’t understand that the secret ingredient that makes a crib design successful is not the frame or the exoskeleton, but the thick interior brush. If that’s not a central component from the start, or if it’s lost, cribs will stop attracting fish. The frame may stay intact and last for decades, but the brush deteriorates much more quickly. If there were some way to re-stock these cribs with interior brush, we could vastly extend their viability and lifetime.

The Vertical Dimension

Height is infinitely more important than length. The higher the walls of the crib extend from the bottom, the more attractive the crib will prove to fish. You want a piece of genuine structure, not something that is just an inconspicuous component of the floor of the lake. In fact, cribs should measure no less than four feet high. Fish want something well above the lake floor, and they like to choose the depth they want to hold while remaining close to the structure.

One of the best fish cribs I’ve ever seen was created entirely by accident. It was rectangular and four feet high, four feet wide, and 12 feet long. It was placed on the ice in 17 feet of water. When the ice melted in the spring, the rocks weighing it down shifted position, and the crib plunged to the bottom on its side. As a result, the crib towered 12 feet from the bottom. Underwater it looked like a skyscraper. Fish flocked to the crib and occupied various stories from top to bottom. A long, dark shadow fell on one side and served as a magnet for fish. In short, the structure turned into an amazingly effective accidental home. Another crib of the same dimensions fell nearby as originally intended but, since it ranged only four feet from the bottom, it attracted only a fraction of the fish the skyscraper did.

Complexity of Design

Since this is not an article about building cribs, I won’t go into the blueprints on how to construct them. The key element in one word is complexity. This refers to the guts of the crib, not the frame. The interior brush should be packed tightly enough to block out most light. Don’t worry about making it so dense that fish won’t be able to get inside. Pockets will form here and there, and fish are astoundingly adept at squeezing into the tiniest spaces. Long branches should extend from the crib on all sides and through all the slats. If possible, include some long branches stuck into the top of the crib to give it some extra dimension. The idea is to create as thick and complex a jungle as possible. The final result will resemble a thick mass of long branches extending from the dense pack inside the crib. The branches should reach from every depth of the crib in every direction and at every possible angle. If your finished crib looks even vaguely tidy, it needs more work.

View from Inside a Fish Crib (c)Eric Engbretson

Designs that Don’t Work from Day One:

Cribs that incorporate Christmas trees work adequately but for a very short time. Christmas trees deteriorate so quickly that in just a year or two, they no longer provide the complex cover that fish desire. In addition, fish will ignore cribs that are too small, too short, or too simple in design.

Examples of poor designs are cribs made of wooden pallets that rest only a couple of feet off the bottom, or cribs with huge spaces between pallets and no interior brush. Star-shaped cribs that resemble the obstacles used on the beaches of Normandy in World War II may look fascinating, but they lack the complexity, shade, and cover to attract fish well. Cribs containing white birch bark or white PVC pipe always fail. After all, fish refuse to be silhouetted against a white background that makes them too visible to predators. This list is scarcely exhaustive: There are many other design flaws in cribs that don’t attract fish.

Location:

Depth

When it comes to location, success depends largely on depth. When cribs are placed shallow enough to let sunlight reach them, they grow algae and other organic material. This serves as a food source for juvenile fish and also makes the cribs fuller and denser. When cribs are placed closer to the littoral zone, they’re much more accessible to the newly hatched fry that will quickly colonize them and provide the food that attracts larger fish.

When I’m scuba diving, I see fish cribs in deep water go largely unused most of the year. The water is colder here and may lack adequate oxygen. In general, these cribs receive visits by fish in fall and winter. On the other hand, fish in shallower water will use a crib virtually year-round. Some of the best fish cribs I’ve seen were ones that weren’t properly weighted. When the ice melted, they floated toward shore and ran aground. When allowed to remain in place, these cribs were quickly covered by algae and were populated immediately by juvenile fish and newly hatched fry. Despite their extremely shallow location, they attracted game fish year after year and even served some fish as a structure for spawning.

The Substrate

Cribs should always be placed on a hard bottom or substrate. If placed on a lake bottom with 12 inches of muck, let’s say, the crib will sink into the muck and you’ll effectively lose a foot of height. Since height is vital to fish, you don’t want to lose it. A muck bottom also eliminates the basement floor.

The Basement Level

Another reason a hard bottom matters is that you want about a foot of clearance between the lake bottom and the base of the crib. If fish can swim underneath your crib in this basement level, you’ve really got something to brag about. Walleyes and bass, by the way, are two species especially drawn to cribs that let them swim underneath.

Plants

If the crib rests in shallow water where plants can grow, it’s often possible to extend the life of the crib almost indefinitely. As multitudes of fish congregate around the crib season after season, their feces can accelerate a lush growth of plants. This patch of vegetation is denser than the surrounding area and creates desirable habitat all by itself. In time, after the interior brush decomposes, it’s possible that tall aquatic plants will replace it, a process that prolongs the lifespan and effectiveness of the crib. If the crib sits in water that’s too deep for plants to grow, none of this growth will take place.

Multiple Cribs in One Location

Cribs located close to each other always outperform single units. Fish will often travel back and forth in a cluster of cribs. Even if they are built alike and placed at the very same depth, they form individual identities, and multiple cribs will be used by different species in various ways. For example, one crib may attract many more rock bass than another that is just a few feet away and populated mainly by sunfish. The differences in the cribs are largely indiscernible to our eyes, but the fish notice subtle distinctions that drive their preferences. The rule, then, is simple: Multiple cribs offer multiple choices and greater numbers of fish.

Regulations

The regulations on the placement of fish cribs are mandated by Natural Resources Departments in many states and other jurisdictions. In my state, Wisconsin, permits for fish crib construction and placement explicitly instruct builders to place them with at least five feet of water over the top of the structure. Since the cribs themselves are typically four or five feet high, the minimum depth for placement is nine or ten feet. The concern here is understandable. Cribs can create hazards for boaters, who may be unaware of their locations. However, if I were placing cribs on my own private lake, free from regulations, I would place them shallow enough so that only two or three feet of water covered the top. This way, I might be able to replenish them with new brush from time to time as the older material disintegrated. This would greatly extend their natural lifespan.

The Future of Artificial Fish Shelters

In recent years, fish-crib makers have gotten very creative and used a variety of materials. Most popular of the new wave of materials are things normally destined for the junk pile or landfill. Today it’s not unusual to see fish cribs made of stacked wooden pallets, plastic, or PVC. They feature clever designs, and I’ve seen some of them underwater in lakes that I frequent. But the truth is that they don’t seem to fare well. While they may be lighter, easier, and cheaper to make, their main drawback is that they lack the size and complexity to prove attractive to fish. The best ones take up the most space and most effectively mimic trees, sunken timber, and other natural elements.

An example of a poorly constructed fish attractant.  Notice the lack of complexity and the large open spaces that provide shade, but nothing in the way of cover. @Eric Engbretson Photo

Fish Cribs as Fish Habitat

Let’s get one thing straight. Fish cribs are definitely not fish habitat. They’re artificial constructions designed to concentrate unusually large numbers of fish in a very small area so fishermen can catch them. Fish cribs do not normally provide the elements fish need for spawning or nesting. At their best, fish cribs merely impersonate fish habitat. In fact, in lakes with an abundance of excellent fish habitat, even the best- made and best-placed cribs will go ignored by fish in favor of superior natural structure. In sum, fish cribs work best in lakes where there is little or no natural structure for fish to use.

Traits of Effective Cribs:

·They reside in relatively shallow water (10 to 15 feet)

·They receive ample sunlight and they support algae and other organic growth

·They are in water that is shallow enough to let submergent plants grow nearby

·They sit on a hard bottom

·They are at least four feet high

·They have a space at the base that lets fish swim under the crib

·They are thickly packed in the center with various sizes of brush and branches

·They have long and complex branches on all faces extending away from the crib

·They have a complex design

·They are placed together with other cribs

·They are in lakes that contain little or no natural structure

Traits of Ineffective Cribs:

·They sit in water that’s too deep (or too shallow if the water’s too warm for fish)

·They sit too deep to receive ample sunlight and support organic growth

·They are in water too deep for plants to grow nearby

·They sit on a mucky bottom

·They are less than four feet high

·They have no space at the base where fish can swim under the crib

·They contain Christmas trees or have little or no brush packed into their center

·They have a design of limited complexity

·They are placed alone

·They are in lakes with abundant natural habitat and structure

Conclusion

As with any set of guidelines and suggestions, there are always exceptions. My observations and conclusions come from years of scuba diving in the northern lakes of the upper Midwest. While complexity of design is universally important, in other parts of the country, many of my suggestions on placement may ignore local conditions and require adaptation. For example, in large southern reservoirs, water temperatures can soar into the 80s and force fish to spawn and live in far deeper water, where lower and more comfortable temperatures prevail. In very clear lakes, sunlight may penetrate 30 feet or more, and plants can grow at greater depths than in other locales. In lakes like these, specific local conditions must be taken into account. Because of such variables, it’s important to have a good understanding of your lake’s ecology and other characteristics. Understanding the specific dynamics of any given lake will help immeasurably when you decide on the best locations for a crib. By Eric Engbretson

PotashCorp Sets New Trend In Tournament Bass Fishing”Helping Nature Provide”

There are countless Bass fishing events that take place across our country each year allowing participants a chance to take home substantial prize money and products. This past weekend was no exception on J. Strom Thurmond Reservoir  in Appleton,Georgia.

 With a first ever of it’s kind, The PotashCorp FishBack Open Team Tournament, contestants competed to raise money and awareness in support of the Georgia Ovarian Cancer Alliance (GOCA) and the North Augusta Fishing Team.  After the two day event, 100% of the proceeds were donated to these two fine deserving groups with $6000.00 and $4000.00 respectively being  awarded.

With a guaranteed payout of $12,000 for first place, more than 125 boats competed in this first annual open. The two man team event goal, was raising money for two great groups. Boats and fisherman from numerous surrounding states, geared up for this unique opportunity to fish this expansive body of water.

Fast boats and seasoned anglers planned to  jockey for a chance at taking home one of the many cash and donated prizes, including two 52″ wide screen T.V’s donated by Fairway Ford.

Before first light on Saturday, hundreds of decked out fishing rigs decended on Wildwood Park and the Tommy Shaw Memorial weigh in at Clark Hill.  Anglers of all levels  including a few FLW pro’s, then discovered fishing wasn’t the only job on hand for the day.

The twist to this groundbreaking Bass tournament concept…….install artificial fish habitat during the event, enhancing the environment and the fishery! Maybe come back on day two and catch a lunker on the habitat unit you installed on Saturday!

That’s right, each boat was required to give something back to the fishery by installing an artificial fish habitat structure at either their first or second stop of day one. Over 150 new artificial habitat units were installed during the event.

More than one strange look was apparent when the requirement was announced. You want  me to put what in my spotless, pristine gel coated water rocket? I barely have enough room for the twenty something rods and hundreds of pounds of tackle we can’t fish without.  Are we going to fit yet more gear and supplies, ropes, cinder blocks, etc.?

No worries, each boat of two fisherman received a Safehouse model habitat by Fishiding.com to unfold and install. These patented, self contained habitat units are made from reclaimed vinyl siding, cemented into a PVC container. Standing about 45″ tall when shipped, the vinyl limbs bend out in all directions and create a “Safehouse” about 7′ diameter and 3′-6″ tall, weighing approximately 15 pounds.

No additional tools or supplies…or mess when putting these habitat units out. Just bend to shape by hand, whatever looks good, then toss over the side. Each artificial fish habitat unit will sink to the bottom and land upright to resemble a bush. The wide limbs create maximum shade, often preferred by bass and forage fish. Nutrients then stick to the vinyl and start the food chain.

The brains behind this first of it’s kind conservation awareness tournament came from the event mastermind, Joey Bruyninckx of PotashCorp.

“Giving something back to the fishery only made sense.” Cancer, Kids and Conservation, what better causes to support?

We met Joey and his team through our involvement with the North Augusta fishing Team. PotashCorp has been a loyal supporter of the North Augusta Fishing Team.( NAFT ) Months back, we were contacted by a hard working young lady named Rosie DeAnnutis, a selfless volunteer for the NAFT. She asked if we may like to get involved in supporting the kids on a cold spring tourney at the same location, Wildwood Park back in March.

We very much wanted to be involved, but because of the timing and the distance, we called on our trusted partners at SOlitude lake Management at their nearby office’s in Charlotte and Raleigh to assist us by speaking to the kids about habitat. SOlitude  has various offices throughout the mid-Atlantic states.  Serving clients in 9 states  including: VA, NC, SC, MD, DE, PA, WV, NJ and NY, offering top notch professional service and advice for all your lake and pond aquatic needs. Aquatic, Fishery, Wildlife and Forestry Biologists, Environmental and Ecology Scientists, all make up the SOlution to a better planet earth.

Matt Phillips, their Aquatic Biologist/Environmental Scientist was happy to help and make the three hour drive to participate. The group discussed fish recruitment, stocking and available habitat. These young, fishing machines embraced the information and wanted to be involved in any habitat restoration plans they could assist with. Matt and Joey began to discuss ideas for the upcoming FishBack Tourney that cold and overcast day as the kids enjoyed the time spent together, outdoors.

The NAFT is open to kids in junior high through high school, ages 11-18. The coach Sean Hall, has a special gift. Gaining the trust and respect of these kids, he loves the outdoors and teaching them about what is important for their future, and the environment. More habitat articles at fishiding.com

Sean brings in DNR officers, Biologists and other related professionals to talk to the kids about boating safety, fish health and species identification to name just a few. “Fishing is only a small part of what these kids take out of being part of the team.”

Although Sean is amazing in how he keeps the kids attention, he certainly can’t do it alone. Jeannie Parks Wilson and Bobbi Boatwright round out the staff to keep this team growing. Getting involved in more events and spreading the message surrounding the multi-faceted benefits of youth fishing teams is their core goal.

After speaking with local DNR officers, it was determined that the lake needed additional habitat, more than any other feasible efforts like stocking, which was another idea and potential option. The lake levels had been extremely low in the recent past which takes a significant toll on fish spawning and recruitment. Additional habitat that fish can utilize to feed, hunt and hide within creates not only big bass, but forage species as well.

This less known concept in habitat improvement is growing Nationwide and moving to installation of inert, artificial materials, that last underwater for decades or longer. In the past, brush piles, Christmas trees and the like have been the norm. Although these materials hold fish and work very well. Their life underwater is short lived due to decomposition, also robbing dissolved oxygen from the water column. Inert materials like boulders, rock and plastics never break down and provide a surface for life to form immediately after submersing.

With over 50% of the Nation’s waters in an impaired state, biologists and esteemed professionals from all the State and Federal agencies are looking for ways to improve water quality before it gets any worse. Aeration, Floating Treatment Wetlands, living shorelines and artificial habitat, are just a few of the tools we are learning have multiple benefits.

These products when placed in the water, attract and convert excessive nutrients like phosphorus and nitrogen into fish food called periphyton. That fuzz that grows on surfaces underwater….”mothers milk” of the underwater world. All fish graze exclusively on this highest known source of food for their first year of life. Unlike aquatic vegetation, these products never die off and continue to process nutrients all year around in a process called biomimicry. This same technology is currently being used in fields like wastewater treatment, fish farming, aquaculture and hatchery settings worldwide.

The Potash Corporation, founded in 1989 is one of the world’s largest producer of Potash, Phosphate and Nitrogen, responsible for 20% of the global capacity through their Canada operations. PotashCorp has built the world’s largest fertilizer enterprise by capacity on world-class potash resources and high-quality phosphate and nitrogen assets. These primary nutrients that crops need, as well as livestock feeds and industrial goods, are an essential part of our everyday lives.

PotashCorp  brought in support from all over for this unique twist on bass fishing. The Clark Hill Committee and Columbia County worked tirelessly for weeks with Joey and his team to make this event the huge success that it was.

Fairway Ford provided registration and support as well as trucks for display on tournament days, as well as prizes for the raffle.

Dixie Riverside A&A Vending services also contributed not only by donating all the food and drinks, but has been an ongoing supporter of the North Augusta Fishing Team.

Fireplaces and More were on hand cooking fresh pulled pork sandwiches, dogs and the like for the two day event, keeping the masses fed.

Zoom baits, another NAFT supporter and integral part of this years FishBack tournament, were on hand with samples of some new baits for all involved and a major part of the planning to make this years event possible. Chris Baxter, Zoom sales manager and FLW pro, has a special connection to this event. After his wife was diagnosed with stage 3 ovarian cancer, he wanted to do more to raise awareness for other women and possibly save a life with early detection. Baxter reached out to Doug Barron with the GOCA.

More on Chris and his partnership with GOCA in a story recently written in Wired2Fish.com.

Doug and his right hand man Chase Powell, were around all weekend to answer questions and provide literature and support regarding ovarian cancer. Passionate outdoors men, these two guys have a soft and dedicated commitment to help women and their families diagnosed with this unfortunate disease.

From black tie events and prestigious supporters, fishing tournaments with shorts and sandals, the message on how to early detect this type of cancer is one of their main goals. Lots of travel and long days are the norm for these two stewards of ovarian cancer support and education.

Kicks 99 radio also was on hand with music and games, proudly showing their support for the kids and the Georgia cancer Alliance.

GreenfishTackle and The Tackle Shop had strong support for their products both on and off the water. Owner Jon Hair not only spent countless hours planning with the team but also got out and caught some fine fish as a contestant in the event.

Seatow was there for all on the water support as well as donating prizes to the raffles.

Loads of bass made their way to the weigh in, almost 8.5 pounds and 7.5 pounds  won the big bass checks for $1000.00 on Saturday and Sunday respectively. The NAFT kids ran to the lake for release of each boats catch like revolving fish doctors, spending needed time to revive tired fish. Two, five fish limits were added together for the total weight of the event, which a number of the top finishers were over 30+ pounds in aggregate!

A unique and welcome surprise for a couple traveling from the Chicagoland area. My wife Renee’ and I were welcomed into this family of fish loving folks, dedicated to helping others less fortunate and bettering others lives. A touching prayer and our National anthem started the event Saturday morning in the dark. Hundreds of eager contestants stood silent with respect, heads bowed and hats off.  Southern hospitality is alive and well in the Augusta area. Take note America, this is how it’s done!

Photos by: Michael E. Johnson Photography 706-832-6762

additional links/stories: ODU, facebook Wired2Fish, potashcorp/facebook

Oklahoma wildlife officials hope fish like tornado debris

  • Oklahoma Debris Spider Block.jpg

    Debris from the recent tornado that swept through Oklahoma is being put to use by state conservation officials, who are submerging it in lakes to form “fish attractors.” (wildlifedepartment.com)

Debris from the recent tornado that swept through Oklahoma is already being put to use by state conservation officials, who are submerging it in lakes to form “fish attractors.”

Cinder blocks scattered by the twister that killed 24 last month have been collected by the Oklahoma Department of Wildlife Conservation, which will use them to make what anglers call “spider blocks,” to sink in state lakes, according to The Oklahoman

“We’ve probably got close to 500 right now,” Greg Summers, of the Oklahoma Department of Wildlife Conservation, told the newspaper. More habitat articles at fishiding.com

Fish congregate around the spider blocks, which get their name from the appearance given by the PVC pipe that sticks out from the cinder blocks.

“Predators use them as an ambush point,” Summers said. “That’s why they are valued as fish attractors because they do attract predators.”

Spider blocks are usually placed at depths of 12 feet or less, and marked for anglers.

Read more: http://www.foxnews.com/science/2013/06/04/oklahoma-wildlife-officials-hope-fish-like-tornado-debris/#ixzz2W0JRnrJw

What Exactly Is Fish Habitat and Why Must We Care?

Forward Post: AFS Journal
What Exactly Is Fish Habitat and Why Must We Care?
Mon Jun 3, 2013 2:29pm
What Exactly Is Fish Habitat and Why Must We Care?Thomas E. Bigford
Office of Habitat Conservation, NOAA/National Marine Fisheries Service, Silver Spring, MD 20910.
E-mail: Thomas.bigford@noaa.gov

“Fish habitat” is a
simple term. We can easily
imagine a fish languishing
under a log or in
a kelp forest, and we can
picture a school of forage
fish zipping through the
water column. We can
also grasp that the preferred
space for many species might change as the seasons change and
the years pass by. But the rest of the story is not quite so simple,
mostly because life is more complicated and knowledge is often
limited. This month’s “Fish Habitat Connections” seeks to demystify
those details so we can appreciate the intricacies in the
fish habitat world and become more emboldened to serve fish
not just as a meal but as they deserve.
Let’s begin with semantics. Each fish occupies its preferred
niche in the ecosystem. The environmental conditions of that
space define the fish’s preference at each life stage—water
temperature, depth, salinity, flow, bottom type, prey availability                                                annual cycles, and much more. It is important for us
as professionals to place those variables in proper context so
that individual fish can survive, fish stocks can flourish, fishery
management can succeed, and society can benefit from our nation’s
waters.
That simplistic summary reflects our hopes, which are
complicated by the reality that we know very little about our
most basic habitat questions. With luck, we know where fish
live throughout their life cycles. But oft times we have few
insights into the shifting preferences of each life stage. Even
that knowledge is elusive unless we have close observations
from multidecadal stock assessments or the insights offered
by a healthy fishery. Almost universally, we rarely understand
the relationships between fish and their habitat.

If a wetland is
dredged, how will the local fish populations change over the
short and long term? If a dam is breached, will the new hydrological
regime support native species or invite invasive species?
If an acre is protected or restored, how will the population respond?
Will harvests increase?
These issues read like the final program at many an American
Fisheries Society (AFS) conference. They have vexed us
as a profession for decades. We must manage fisheries with the
best available information, scant as it might be. And we must
identify our primary needs so that gaps are addressed.
COLUMN
Fish Habitat Connections There is also the still-new concept of ecosystem-based approaches.
Habitat must be an essential variable in stock assessments,
but those analyses must be conducted with an ecosystem
in mind. Those perspectives can be as important as data. Without
that challenge, we won’t even know we have a data gap.
Considering how complex this simple topic can be, and
how it reflects human pressures from our coasts to the mountains,
it is probably no surprise that we continue to lose habitat
function at alarming rates. Along our oceans, marine and estuarine
wetland loss was three times higher between 2004 and
2009 than in the previous 5 years (Stedman and Dahl 2008;
Dahl 2011). Inland wetland loss is not as severe, but hundreds of
rivers representing thousands of river miles are compromised by
blockages that prevent fish movement upstream or downstream.
The first-ever national fish habitat assessment found that 53%
of our estuaries are at high or very high risk of habitat degradation
(National Fish Habitat Board 2010). Given those numbers,
it is unfortunate that those places provide vital nursery habitats
for many of our favorite fish.
As fishery professionals from all disciplines, our assignment
is to combine our skills to protect important habitats and
restore those that are degraded. Our mission will be slightly
less daunting if we and our partners can set a pace to match
the steady pressure of human population growth and looming
challenges such as climate change. AFS represents an incredible
knowledge base. If anyone can analyze our habitat knowledge,
fill our priority gaps, apply lessons learned, and improve habitats
for the benefit of all, it is us.

More habitat articles at fishiding.com
Next month we will shift from the nuances of semantics
to the harsh realities of the challenge before us. It is imperative
that we engage now! Economic and ecological facts urge AFS,
its units, each of us, and our home institutions to accept the challenge.
We will explain the opportunities before us and how our
collective skills are needed for success.
REFERENCES
Dahl, T.E. 2011. Status and trends of wetlands in the conterminous
United States 2004-2009. U.S. Department of the Interior, Fish
and Wildlife Service, Washington, D.C. 108 pp.
National Fish Habitat Board. 2010. Through a fish’s eye: the status of
fish habitats in the United States 2010. Association of Fish and
Wildlife Agencies, Washington, D.C. 68 pp.
Stedman, S., and T. E. Dahl. 2008. Status and trends of wetlands in the
coastal watersheds of the Eastern United States 1998 to 2004. National
Oceanic and Atmospheric Administration, National Marine
Fisheries Service, and U.S. Department of the Interior, Fish and
Wildlife Service, Washington, D.C. 32 pp.

The unexpected consequences of fighting Eurasian Watermilfoil, preventing fish from successfully reproducing?

Lake on the Brink:

The unexpected consequences of fighting Eurasian Watermilfoil

By Eric Engbretson

 

 

In 2012, Greg Matzke, a fisheries biologist for the Wisconsin Department of Natural Resources, made a startling discovery on Florence County’s Lake Ellwood. During a comprehensive fish survey which included spring, summer and fall netting and electrofishing surveys, Matzke discovered that all of the lake’s largemouth bass were older than 5 years of age, with approximately 91% of the largemouth bass population being at least seven years old.  The absence of younger fish indicated a recruitment failure for a number of years.  Such failures in largemouth bass recruitment over multiple years are unprecedented in the state of Wisconsin.

 

“The current largemouth bass population is in serious trouble,” Matzke reported. “It appears that natural reproduction of largemouth bass has not occurred since 2007. As these older/larger fish move through the population, a significant reduction in largemouth bass abundance will take place, with the potential for the complete loss of this species of fish unless the current situation changes.”

 

Matzke next began looking at the lake’s panfish population.  What he found was stunning. Overall, the lake’s panfish abundance had fallen an estimated 75% in just the last 10 years, with bluegill and rock bass abundance down an estimated 65% and 89% respectively, showing that these populations also appear to be collapsing. Intense sampling throughout 2012 found only a single black crappie under six years of age, showing another alarming recruitment failure in several consecutive years. When Matzke analyzed the ages of Lake Ellwood’s northern pike population, the results were even more disappointing: There were no pike under the age of eight!

 

Matzke stared at the data he had collected. His department had never seen a mystery like the absolute and complete recruitment failures of native northern pike, black crappie, and largemouth bass (along with significant reductions in recruitment of other panfish populations). He shared his findings with other fisheries professionals across the state and they all said the same thing.  They had never seen a collapse like this in their careers. Matzke and his team scrambled to collect more data and tried to find a cause that could have brought the fish to the brink of extirpation in Lake Ellwood. Surveys from 2002 had shown normal abundance, size structure, growth, and recruitment in all of these species. What had happened in the last ten years that was preventing fish from successfully reproducing?

 

The only thriving species of game fish in the lake were smallmouth bass. Their abundance and size structure had grown in the last decade and recruitment was high.  This suggested that the problem was targeting specific species of fish. Because Lake Ellwood’s smallmouth bass were doing so well while the other species were collapsing, the focus turned to the lake’s historically sparse but important aquatic plant community. All the species showing recruitment failures are highly dependent on aquatic vegetation for spawning as well as cover and food for their young. Matzke observed that smallmouth bass seem to be different. “The fact that this species was not affected by the reduction in plant life,” he said, “is not a major surprise since as a species smallmouth bass are less dependent on aquatic vegetation.”

 

The Smoking Gun

 

Eurasian Water Milfoil was discovered in Lake Ellwood in 2002. Herbicide treatments began in 2003 and increased every year. By 2007 recruitment of northern pike, largemouth bass and black crappie had come to an end. “When I started to analyze the data it was strikingly obvious to me that there are some problems associated with the herbicide”, said Matzke. When he graphed the fish abundance (by year class) over the last decade and overlaid it with a graph showing yearly herbicide treatments, he found what he believed was a critical connection.  Fish numbers fell as the amount of herbicide increased.  Interestingly, in the year following a relatively low application of herbicide, young bluegill (and black crappie to a much smaller degree) began to appear again, but their numbers are still very low and they will likely disappear before they reach age 2.

 

 

 

Year class strength, indexed using age estimation to determine number of individuals of each year class captured during a 2012 comprehensive survey, for northern pike, black crappie, largemouth bass and bluegill plotted against the number of pounds of 2,4-D (not acid equivalent) used to treat aquatic plants in Lake Ellwood, Florence County, 2003-2012.

 

 

 

“We still wonder which stage of reproduction has failed in these species”, says Matzke. “Aquatic vegetation plays a major role in spawning site selection and in the survival of eggs and fry. Plants are also the source of primary production providing food and habitat for young fish and prey items, including invertebrates and minnows. It seems likely that one or all of these important phases of reproduction are dwindling in Lake Ellwood.”

 

On April 17, 2013 Matzke met with the Lake Ellwood Association to reveal his data and conclusions. He told the group, “The main cause for failed northern pike, largemouth bass and black crappie recruitment (along with the massive reduction in panfish abundance) appears to be the loss of aquatic vegetation.” The 2-4-D herbicide used on Eurasian watermilfoil had been successful in reducing the abundance of this invasive species significantly. Conversely, other native plants were also harmed by years of chemical treatment. Matzke said he has no reason to believe the chemicals have directly caused a failure in reproduction of any species of fish in Lake Ellwood. However, Matzke does believe that the chemicals have indirectly caused recruitment failure by eliminating too many of the aquatic plants young fish need in order to survive.  Matzke has called for a change in the way the Lake Ellwood Association has been managing the lakes aquatic plants.  He recommended that further chemical treatments for milfoil be stopped.

 

“First and foremost,” says Matzke, “we need to promote and strengthen aquatic vegetation in Lake Ellwood.” He stresses the role of aquatic vegetation in spawning and concludes that the loss of vegetation (including the invasive milfoil) has almost certainly wiped out a great deal of forage for young fish.

 

It seems that milfoil treatments controlled the invasive plant but also jeopardized the health of the lakes fishery. Today the lake contains a dwindling and rapidly aging population of largemouth bass, black crappie, northern pike, and bluegill. Matzke hopes the plants will come back in time for the remaining old fish to produce at least one year class before they die. If that doesn’t happen, many fish populations will likely be extirpated from Lake Ellwood. New fish can be stocked, of course, but the lake would lose the unique genetic lineage of the fish that have lived there for thousands of years.

 

 

The Future

 

Could chemical herbicide treatments for Eurasian watermilfoil be reducing fish recruitment in other lakes? None of the other lakes that have been receiving chemical treatments have had their fish populations surveyed this intensely. Large scale recruitment problems due to loss of important plant cover could be taking place throughout the region where the invasive plant is now being fought. There is no way to know if this is happening, and frankly, up until now, there has been no reason to find out.  Fisheries experts around the state are only now learning of Matzke’s findings on Lake Ellwood. In the future, they will likely start paying more attention to fish recruitment on lakes treated for Eurasian watermilfoil which would allow the Department of Natural Resources to determine whether this crisis is an isolated instance or a more widespread problem.

 

In the meantime, it’s a race against time for Lake Ellwood’s native fish. The question remains: Will the plants come back in time to save these fish populations?

GRDA to host ‘Build A Brush’ Saturday

 Spidery habitats

Cheryl Franklin / Grove Sun

Spidery habitats

Fish habitats built by volunteers at Build a Brush workshops.Kaylea M. Hutson

Anglers and others who have a passion for all things Grand Lake will have a chance to learn how to build an artificial fish habitat on Saturday, during a workshop sponsored by Grand River Dam Authority.

The “Build A Brush” hands-on workshop, set for 9 a.m. Saturday, May 11, Wolf Creek Park, is designed to teach people how to build artificial fish habitats made using cement blocks and plastic pipes.

Members of the GRDA staff will be on hand during the event, to teach those gathered how to make the habitats, known as “spider blocks” because of the way the black plastic pipes resemble spider legs.

Jacklyn Jaggars, assistant director of GRDA ecosystems and lake management, said the spider blocks become fish habitats once immersed in the lake, because moss and algae grow on the pipes. Five or six blocks placed together provide cover for even the smallest fish.

Those in attendance will have the opportunity to take home several blocks, and encouraged to place them in their favorite fishing spots, explained Jaggars.

The workshop is set for 9 a.m., Saturday, May 11, at the Wolf Creek Park. The event is free, but Jaggars said reservations are encouraged to ensure they have enough materials. To register, persons may call 918-256-0723.

This is the first of two “Build a Brush” workshops. The second workshop is set for Saturday, June 1, at Cherokee State Park, below the Pensacola Dam in Langley. More habitat articles at fishiding.com

Fisheries habitat plan aims at ensuring great fishing for the long term

NEWS RELEASE — St. Paul, MN – Dirk Peterson won’t tell anglers where to catch a big fish, but he can tell them what’s needed to make sure there are big fish to catch when they get there.

More and more these days, he’s boiling it down to three words: good fish habitat. More habitat articles at fishiding.com

Peterson is in charge of the Minnesota Department of Natural Resources’ (DNR) fisheries section, which has just launched a new fisheries habitat plan. It outlines a strategic road map for making sure the state’s 10,000 lakes and hundreds of rivers and streams continue to provide the healthy aquatic habitat underpinning great fishing.

Pete Jacobson, a DNR fisheries research supervisor and one of the plan’s authors, makes it sound pretty simple. “The reason we have good fishing in Minnesota is because we have many lakes and streams with good water quality and habitat,” he said. “Healthy fish habitat is critical.”

But assuring the future of healthy aquatic habitat is anything but simple, because clean water depends on all that happens across a watershed, the hundreds or thousands of acres that drain into any particular lake or stream.

“When you lift a fish out of the water, that fish is a reflection of all that happens on the land,” Peterson said. “If we want to maintain great fishing, we need to focus more effort at the landscape and watershed scale.”

Peterson compares fisheries management to a three-legged stool: one leg is stocking fish, one leg is regulations that help control harvest, and one leg is habitat. Historically, the first two legs have been a little longer and more robust than the last one. The new plan aims to rectify that imbalance by directing staff and other resources to habitat protection and restoration.

While past fisheries habitat projects focused more on near-shore efforts such as protecting aquatic vegetation and stream channel improvements, the new approach seeks to move away from the water’s edge to encompass entire watersheds.

Because the DNR has little authority over land use – a chief determinant of water quality – working at the watershed level will rely more extensively on collaboration and coordination with other DNR divisions, local government, landowners, and other state and federal agencies.

Now there’s collaboration with DNR’s Forestry Division and local soil and water conservation districts to protect the watersheds of lakes with healthy populations of tullibee, a coldwater species sensitive to water quality, which provides important forage for game fish.

In the metro region, watershed scale collaborations with local government and other agencies have helped protect several trout streams, including Dakota County’s Vermillion River, a trophy brown trout stream just a half hour from downtown St. Paul.

While DNR fisheries has undertaken a few larger scale habitat projects before, they tended to be few and far between because there was little funding for big-picture, long-term approaches. The passage in 2008 of a state constitutional amendment dedicating a portion of a sales tax hike to the outdoors and to clean water has changed that. Much of the new habitat plan, available on the DNR website athttp://www.files.dnr.state.mn.us/fish_wildlife/fisheries/habitat/2013_fishhabitatplan.pdf, is aimed at better coordination and focus of funding sources to achieve the most bang for the buck.

An increase in fishing license fees – approved by the Minnesota Legislature last year – also is helping to put more focus on fisheries habitat work.

“We’ve always talked about habitat, but there rarely was adequate funding to really attack it at the appropriate scale,” said Jacobson, the fisheries researcher. “The constitutional amendment changes that, and we need to take advantage of it. The amendment is a mandate from the people for us to take fish habitat conservation seriously. This plan helps us do that.”By Site Editor

B.A.S.S. Federation Nation Improves Habitat with long Term Advantages

Artificial Habitat Benefits Bass Fisheries

DateFriday, March 8, 2013 at 9:21AM  ActivistAngler.com

Fisheries in West Virginia and New Mexico are showcasing a new generation of manmade habitat, thanks to innovative state conservation directors in the B.A.S.S. Nation (BN).

Both Jerod Harman and Earl Conway saw the need for effective and long-lasting habitat in reservoirs that endure huge water fluctuations on a regular basis. More habitat articles at fishiding.com

“Climate change is already impacting the Southwest,” said New Mexico’s Conway. “Over-allocation of water rights and drought have drained many reservoirs in New Mexico and west Texas. Shoreline and aquatic vegetation is gone and replanting is futile when lake levels fluctuate 20 feet or so every year.

“That’s where floating islands come to the rescue.”

In West Virginia, meanwhile, the West Virginia BN has teamed with a company that makes fish habitat from recycled vinyl and reclaimed PVC to build an “oasis for bass” in Sutton Lake, according to Jerod Harman.

It consists of pea gravel, spider blocks, artificial structures fromFishiding, and vegetation growing in a 5,000-square-foot cage on a mud flat, with a creek channel nearby.

“The artificial structures attract the bass looking for a place to spawn,” Harman explained. “The pea gravel provides the correct bottom structure for bedding.

“When the young bass hatch, the artificial structures help provide a protective environment. The periphyton (mixture of algae, microbes, and bacteria that forms the base of food chain) will provide nutrients for growth, and, later on, the small bass fry can relocate to inside of the vegetation cage for protection from predators.

“This is something that I am really excited about!”

Harman added that he believes the habitat made by Dave Ewald’s Illinois company, which features vinyl strips attached to a heavy base, will greatly enhance periphyton growth, as well as provide better cover for survival of young bass than will the spider blocks alone.

“The structures are ready for installation right out of the box, and David was great to work with,” the conservation director said. “I would definitely recommend these, especially for a small group of volunteers who need to complete a larger-scale project in a limited amount of time.”

Conway and the New Mexico BN also are growing periphyton, but on floating islands instead of vinyl strips. One of those islands, complete with spawning platform, won the 2010 Berkley Conservation Award and was the first step in what the conservation director hopes will be a major habitat restoration project for Elephant Butte.

Bruce Kania’s Floating Island International, a Montana company, has provided the New Mexico BN with prototypes and expertise.

“Floating islands aren’t new,” Conway said. “They occur in nature and have a proven track record for improving water quality and enhancing fish production, but I think that we are just beginning to realize how they can add an entirely new dimension to habitat restoration options.

“My experience is that the shade and food they provide makes them better fish attractors than boat docks or tire water breaks. They are being used more often in public waters and it is just a matter of time until someone wins a major tournament or catches a monster bass off a floating island.”

(This article appeared originally in B.A.S.S. Times.)

Floating Islands Southeast is offering a free webinar

Our first Webinar for 2013, BioHaven® Floating Island Technology Overview & Update, will be Friday, March 15 at 11am EST.

This is a FREE Webinar.

This session will provide an updated, general technology overview, and will include:

  • BioHaven® Floating Islands technology (Floating Treatment Wetlands)
  • Leviathan – adding circulation to increase results
  • BioCoral – increasing surface area
  • BioSwale – “in ditch” treatment
  • Living Shoreline – alternative to conventional solutions

We recommend/encourage inviting scientists, engineers, facility/municipality managers, and anyone interested in improving water quality, creating habitat and or preserving shorelines.

More habitat articles at fishiding.com

To join this free webinar, send an email requesting “log on” information to: info@floatingislandse.com.

You can invite as many others as you like, but they must also send a request for “log on” information.  Each “log on” is unique and they will not be able to use yours.

Please note – you must have the “log on” information that is provided by the webinar software ilinc.  About 24 hours prior to the session, you will get an email from the ilinc software that will provide you with your unique “log on” information.  If you have any questions, please call us at (888) 660-3473.

For ilinc technical support, please call (800) 799-4510.

BioHaven Floating Islands

Technology Overview & Update

Free – Webinar

Friday, March 15

at 11:00am EST

Submit your request to join this free webinar to:info@floatingislandse.com

24 hours prior to the webinar, you will receive the log on information and password to join this free webinar.  For ilinc technical support, please call (800) 799-4510.

BioHaven® Floating Islands biomimic nature and provide a “concentrated wetland effect” that can help solve many environmental problems challenging our water and wildlife. Unlike natural or constructed wetlands, they can be launched in any depth of water and are unaffected by varying water levels.

Floating Island SE

(FISE) is an exclusive and licensed manufacturer of BioHaven® Floating Islands and this proprietary technology.  FISE works with universities, municipalities, government agencies, engineering firms, private parties and various environmental strategic partners to design and sell customized solutions that leverage the BioHaven® Floating Island technology.

Phone: (888) 660 3473          Website: www.floatingislandse.com          Email: info@floatingislandse.com

Volunteers complete fish cribs for Brevort Lake

MORAN, Mich. (AP) — Using volunteers, 100 cords of hardwood, more than 2,500 cement blocks and 418 Christmas trees, the Straits Area Sportsmen’s Club and Brevort Lake Association put the finishing touches on an 11-year project designed to improve fish habitat. More habitat articles at fishiding.com

“It’s been rotten this year,” SASC President Louis Colegrove told The Evening News of Sault Ste. Marie ( http://bit.ly/1055YlK ). “Real bad conditions — a lot of slush.”

Colegrove added that was especially tough on the core group of volunteers.

“Most of our guys are in their 70s and 80s,” he said, but that did not deter them from completing their task.

When the ice melts later in the spring and the final string sinks in the center of the lake — roughly defined as southwest of Davis Road — the work crews will be responsible for 209 new fish cribs.

“Brevort’s a pretty barren lake,” said Colegrove of the need for the project as large swaths of the lake bottom are comprised solely of sand with little other structure or growth.

The cribs, which stand 4- to 5- feet high, will provide long-term habitat for a variety of fish species living in the lake.

Colegrove said fisheries biologists have given varying estimates regarding the life span of the new reefs and, from that information, he believes they will last somewhere between 50 and 100 years. He also noted that remnants of some of the reefs placed by the Civilian Conservation Corps in the 1930s still remain on the lake bottom to this day.

Colegrove was quick to credit Nelson Logging of Rexton and the Hiawatha National Forest Stewardship program for the 8-foot-by-8-foot sections of hard maple and birch utilized in the construction.

“That saved us a thousand dollars right there,” said Colegrove.

Maverick Construction, Inc. of St. Ignace was also a key player over the past two years, donating all of the cement blocks required to sink the cribs.

The avid angler says he is looking forward to visiting the reefs on future outings, adding that assisting fisheries biologists with various research projects on Brevort has really opened his eyes to this body of water’s potential.

“You can’t believe the fish that are in that lake,” he concluded.

Maps complete with GPS coordinates of all the new fish reefs will be available at Ace Hardware in St. Ignace and KNV Grocery in Moran.

___

Information from: The Evening News, http://www.sooeveningnews.com

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