Responsible Manufacturing, Construction, and Deployment of Plastic Habitat
Freshwater fish habitat declines as water bodies age due to the cumulative ecological
processes of increased sedimentation, nutrient buildup, and decay of submerged wood
and other plant materials. As this process occurs, habitat restoration has emerged as
an essential and popular fisheries management strategy to reinvigorate aging fisheries.
Artificial habitats offer a promising approach in many systems to counteract decline,
with plastic structures emerging as a solution.
Plastics resist natural decay and are impervious to the forces that degrade traditional
materials like wood. Their longevity ensures the structures endure in dynamic
environments, providing lasting support for aquatic life. Additionally, their lightweight
and adaptable properties enable efficient transport and deployment, making them a
practical choice for both small- and large-scale habitat restoration efforts. When
sourced from recycled materials, plastic habitats also present an opportunity to
repurpose waste, simultaneously addressing ecological and environmental challenges.
Despite the growing popularity of plastic artificial fish habitats, the field lacks
standardization. Clear guidelines for manufacturing, ecological compatibility, and
on-site assembly are essential to maximize their benefits while ensuring environmental
safety. Establishing these standards is critical to safely scaling up the use of plastic
habitats and unlocking their full potential to restore, sustain, and enhance freshwater
ecosystems.
Avoidance of Toxic Additives
One of the primary concerns when using plastic in freshwater habitats is the potential
leaching of toxic additives or chemicals into the water. Compounds such as phthalates,
heavy metals, and certain stabilizers can negatively impact water quality and harm
aquatic life. To mitigate these risks, materials should be chosen based on their safety
and environmental compliance certification. The NSF/ANSI 61 certification
addresses concerns regarding the safety assessment of plastic used for potable water.
Additionally, selecting plastics that do not require a Proposition 65 (Prop 65) warning
is vital. Prop 65 is a regulatory framework in California that identifies substances
known to the State of California to cause cancer, birth defects, or reproductive harm.
Plastics that are certified free of Prop 65-listed chemicals are considered safe for use
in sensitive environments. Manufacturers can ensure compliance by sourcing materials
with verified safety data sheets (SDS) and certifications attesting to the absence of
harmful substances.
Durability Considerations
In addition to ecological safety, the long-term success of artificial habitats depends on
their durability. With growing concerns regarding the impacts on human health from
microplastics (small pieces of plastic less than 5 millimeters in length), the structural
integrity and, therefore, longevity of habitat materials must be a priority. Two critical
factors in material performance are UV stability and abrasion resistance.
UV Stability: Exposure to sunlight can cause many plastics to degrade over time,
resulting in brittleness, fading, or loss of structural integrity. UV-stabilized plastics,
which incorporate additives such as hindered amine light stabilizers (HALS) or
UV-absorbing pigments, are designed to resist photodegradation. This property is
significant for habitats deployed in shallow waters or areas with considerable sun
exposure, ensuring their effectiveness and longevity. UV stabilizers should be avoided
if the goal of the artificial habitat is to promote the growth of aquatic organisms on
the material’s surface. Stabilizers may also not be necessary if structures are deployed
at an adequate depth to avoid UV exposure.
Abrasion Resistance: Freshwater habitats often encounter mechanical wear from
sediment movement, flowing water, wave action, and human interactions. Specially
engineered thermoplastics offer high abrasion resistance. These plastics maintain their
surface integrity and structural strength even under harsh conditions, making them
well-suited for environments with high friction or turbulence. Additionally, the
deployment depth and location of the habitat can mitigate the potential for
mechanical breakdowns. Sites should be selected considering boat traffic, water flow,
and wave action. Placement in areas such as coves or on the slopes of a secondary
point may provide protective refuge not available in the main channel, on shallow
flats, or in high-traffic areas.
Virgin, Recycled, and Reclaimed Plastic
When selecting plastics, it is crucial to consider sustainability and safety. Prioritize
using recycled or reclaimed plastics to reduce the demand for virgin materials,
conserve resources, and minimize environmental impact. However, when working
with reclaimed plastics, it is essential to thoroughly understand their prior usage to
assess potential contaminants or compromises in material integrity. This ensures that
reclaimed materials are safe and suitable for their intended applications, striking a
balance between environmental responsibility and functionality. Both recycled and
reclaimed plastics offer the opportunity to close the loop on plastic waste, with
recycled plastic minimizing the risk of unknown previous use.
Processes
Stringent quality control measures throughout manufacturing, packaging,
construction, and deployment should ensure that no substandard materials enter
ecosystems. Manufacturing artificial habitats requires a meticulous approach to
minimize environmental impact, particularly regarding material waste and preventing
“passenger plastics”- unintended plastic fragments that can degrade into microplastics.
The cutting and shaping processes should be optimized for minimal waste. Any
off-cuts and defective products should be recaptured and recycled. Additionally,
suppose products are to be scarified or textured to encourage the colonization of
aquatic organisms. In that case, the resulting product must once again be cleaned
before packaging or construction to ensure the removal of all “passenger plastic”.
Once located within the watershed, the onsite construction element of artificial
habitat offers a final opportunity to prevent the unintended introduction of
“passenger plastics” into the environment. Using ground cover (such as tarps or
sheeting), minimizing onsite alterations, and recapturing plastic waste ensures that the
artificial habitat enters the system as clean as possible.
Proper anchoring and deployment of artificial habitats are crucial to ensuring their
stability, functionality, and longevity. The anchoring system must use appropriate
weights and durable materials to securely hold the habitat, preventing displacement
caused by mechanical wave action, wind, or boat traffic. The deployment depth
should be carefully chosen to avoid high-energy zones where such forces are most
potent while also considering seasonal water level fluctuations and potential
drawdowns to ensure the habitat remains effective and accessible. Flexibility in project
design should allow for adjustments to accommodate changes, maintaining habitat
benefits across varying conditions. Additionally, it is essential to plan for the
reclamation of the habitat, incorporating features that enable safe and efficient
removal of structures if they become damaged, obsolete, or need relocation, thereby
preventing debris accumulation and preserving the integrity of the aquatic ecosystem.
Summary Review
The restoration of freshwater fish habitats using plastic structures offers a practical
and innovative approach to countering the ecological decline of aging water bodies.
Plastics provide durability, adaptability, and sustainability through their long-lasting
properties and potential for recycling. Ensuring the safety and effectiveness of these
habitats requires a careful selection of materials, with an understanding of toxic
additive leaching, UV degradation, abrasion resistance, and the use of recycled
materials. Adopting best management practices that include stringent manufacturing
standards, waste plastic recapture, and thoughtful deployment practices will be
essential to fully realize the potential of plastic fish habitat while safeguarding
environmental integrity.
For further information on habitat best management practices in reservoirs in general,
refer to Best Management Practices Manual – Friends of Reservoirs
Authors
Steven Bardin Pro Lake Management LLC/ Co-Owner BBSG
Gene Gilliland Conservation Director B.A.S.S.
Dave Terre Texas B.A.S.S. Nation Conservation Director
Gary Klein Major League Fishing Co-Founder/Angler/ Co-Owner BBSG
Standardized Questionnaire for Artificial Habitat Manufacturers
Are the plastic types of all materials known? (PVC, HDPE, LDPE, Other)
Do you review the plastic supplier’s ingredients and additives through an SDS sheet?
Does the plastic contain plasticizers or have potentially toxic coatings?
Does the product carry a Prop 65 Warning?
Is the material recycled or reclaimed?
If recycled or reclaimed, is the previous use known?
Do you recapture drill cuts and skeleton plastic?
Is your product cleaned before shipping?
Are your products packaged to minimize waste?
Are tools required to build your product on-site?
Will the product need to be altered before deployment?
Standardized Questionnaire for Internal Review of Projects
Is the planned habitat commercially manufactured?
If YES, is it manufactured according to the above-recommended guidelines?
If NO, is the planned habitat homemade using plastic?
Are the plastic types of all materials known? (PVC, HDPE, LDPE, Other)
Does each plastic component of the habitat have an NSF/ANSI 61 certification stamp?
Does the plastic contain plasticizers or have potentially toxic coatings?
Are the plastic materials recycled or reclaimed?
If the material is recycled or reclaimed, is the previous use known?
Will you recapture drill cuts and skeleton plastic?
Will glues or adhesives be used?
Will the habitat be built within the watershed?
Will a tarp or ground covering be used at the build site?
Is the habitat cleaned before deployment?
Does the water body experience drawdowns or drought?
Do we have a current hydrographic map of the water body to determine optimum locations?
Have sites been selected to avoid mechanical wear?
Commitment to Review and Adopt
Below is a list of reviewers who have committed to following or implementing the
standards. Manufacturers have provided SDS sheets and a review of their
manufacturing process to the authors and are committed to providing the same to
your organization.
If you would like to add your name to the list below as an official reviewer and
adopter, please contact the author above.
Commercial Manufacturers Who Have Committed to Adopt
MossBack Fish Habitat – David King, President/Owner
Submit SDS request to Tracey Rosenau at tracey@mossbackfishhabitat.com
Pond King Inc. – Brad Metzler, President/Owner
Submit SDS request to Jill Roush at marketing@pondking.com
Texas Hunter Products – Cody Borgfeld
Submit SDS request to cody@texashunterproducts.com
