Invasive Species Removal – Mechanical Methods to Remove Invasive Plants
Invasive species adversely impact their introduced environments by causing environmental, ecological, and economic damages. Due to the reproductive biology and competitive strength of many invasive species, they can be extremely difficult or impossible to eradicate once established. Early management interventions such as removal and eradication programs can help control or eliminate populations of invasive aquatic plants. Physical or mechanical removal can be accomplished through capture by methods such pulling, dredging, raking, or suffocation. Though successful in some circumstances, physical removal efforts can be intensive, expensive and take numerous years. Physical removal can break whole plants into fragments that can travel and propagate elsewhere; extreme care must be taken to remove plants by the entire root system and keep them intact. Application, eradication success, and management implications are discussed in these syntheses.
Rating:
Syntheses in this intervention scored mixed CEESAT ratings; 12 syntheses scored poorly but 3 reviews scored Green in at least 1 or more categories (Smith & Sutherland 2014, Smokorowski & Pratt 2007, Roni et al. 2008). These three reviews able to demonstrate in part, defined eligibility criteria, comprehensive sources, detailed methodology, or examination of effect modifiers.
RASCAT scoring was mixed for this intervention; most syntheses reviewed studies based in habitats, climates, and countries relevant to Canada, but many syntheses did not demonstrate any consideration of implications, practical advice, or recommendations for decision-makers. Many of the syntheses were also not published recently.
Photo credit: U.S. Fish and Wildlife Service Northeast Region
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Roni, P., Hanson, K., Beechie, T., Pess, G., Pollock, M., & Bartley, D.M. (2005)
Habitat rehabilitation for inland fisheries: Global review of effectiveness and guidance for rehabilitation of freshwater ecosystems.
Title: Habitat rehabilitation for inland fisheries: Global review of effectiveness and guidance for rehabilitation of freshwater ecosystems.
Authors: Roni, P., Hanson, K., Beechie, T., Pess, G., Pollock, M., & Bartley, D.M.
Journal: NA
Year: 2005
DOI: NA
Species or groups: Tamarisk, salt cedar, Japanese knotweed, reed canary grass, giant reed, leafy spurge, cottonwood, willow
Other sources of evidence: https://www.conservationevidence.com/actions/1228
Abstract: The degradation of inland aquatic habitats through decades of human activities has lead
to massive efforts to rehabilitate freshwater habitats for fisheries and aquatic resources
in watersheds throughout the world. Many texts have been written on techniques
for rehabilitation though no comprehensive worldwide review of the effectiveness of
techniques has been undertaken. This paper reviews published evaluations of freshwater
habitat rehabilitation projects, including studies on roads improvements and sediment
reduction, riparian and floodplain rehabilitation, placement of habitat structures in lakes
and streams, addition of nutrients to increase aquatic production and other less common
techniques. In particular, the authors summarize what is known about the effects of
various techniques for restoring natural processes, improving habitat, and increasing
fish and biotic production. Recommendations on limitations of techniques, which
techniques are effective, as well as information on planning, prioritizing and monitoring
rehabilitation projects are also provided.
Despite locating more than 330 studies on effectiveness, as well as hundreds of
other papers on rehabilitation, it was difficult to draw firm conclusions about many
specific techniques because of the limited information provided on physical habitat,
biota and costs, as well as the short duration and scope of most published evaluations.
However, techniques such as reconnection of isolated habitats, rehabilitation of
floodplains and placement of instream structures have proven effective for improving
habitat and increasing local fish abundance under many circumstances. Techniques that
restore processes, such as riparian rehabilitation, sediment reduction methods (road
improvements), dam removal and restoration of floods, also show promise but may take
years or decades before a change in fish or other biota is evident. Other techniques such
as bank protection, beaver removal and bank debrushing can produce positive effects
for some species but more often produce negative impacts on biota or disrupt natural
processes.
Comparing the cost-effectiveness of different types of rehabilitation techniques
was not possible because few evaluations reported various costs or economic benefits;
however, estimates of average costs for various techniques are provided. Monitoring
and evaluations clearly need to be designed as part of the rehabilitation action. The
authors discuss the key steps to consider when designing monitoring and evaluation of
rehabilitation actions at various scales.
Similar to less-comprehensive reviews of rehabilitation, this review demonstrates
three key areas lacking in most rehabilitation projects: 1) adequate assessment of historic
conditions, impaired ecosystem processes and factors limiting biotic production; 2)
understanding upstream or watershed-scale factors that may influence effectiveness
of reach or localized rehabilitation; and 3) well-designed and -funded monitoring and
evaluation. These are the same factors that consistently limit the ability of published
studies to determine the success of a given technique at improving habitat conditions
or fisheries resources. Finally, this review suggests that many habitat rehabilitation
techniques show promise, but most have not received adequate planning, monitoring or
cost-benefit analysis.
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Smokorowski, K.E., & Pratt, T.C. (2007)
Effect of a change in physical structure and cover on fish and fish habitat in freshwater ecosystems – a review and meta-analysis
Title: Effect of a change in physical structure and cover on fish and fish habitat in freshwater ecosystems – a review and meta-analysis
Authors: Smokorowski, K.E., & Pratt, T.C.
Journal: Environmental Reviews
Year: 2007
DOI: https://doi.org/10.1139/A06-007
Species or groups: Bluegill, Largemouth bass, Northern pike
Other sources of evidence: https://www.conservationevidence.com/actions/1228; https://www.conservationevidence.com/actions/1314
Abstract: Aquatic resource managers are continually faced with construction or site development proposals which, if allowed
to proceed, would ultimately alter the physical structure and cover of fish habitat. In the absence of clear quantitative
guidelines linking the change in habitat to fish, resource managers often use the change in habitat area as a basis for
decisions. To assess the weight of scientific evidence in support of management decisions, we summarized both the observational
and experimental freshwater fish-habitat literature. We then extracted data from experimental studies (where possible)
for inclusion in a meta-analysis, to provide a more rigorous assessment of the published results of experimental
habitat manipulations. We found relatively strong and consistent correlational evidence linking fish and physical habitat
features, yet inconsistent evidence when narratively reviewing the experimental literature. On the whole, decreases in
structural habitat complexity are detrimental to fish diversity and can change species composition. Increases in structural
complexity showed increases, decreases, or no measurable changes in species and (or) communities. The majority of our
meta-analyses resulted in supporting a direct link between habitat and fish abundance or biomass, with fish biomass responding
most strongly to habitat change. Habitat alterations are most likely to affect individual species or community
structure, and thus evaluating the extent of the effect on a biological basis depends on management objectives.
Assessment of reliability and robustness (CEESAT)
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Roni, P., Hanson, K., & Beechie, T. (2008)
Global review of the physical and biological effectiveness of stream habitat rehabilitation techniques
Title: Global review of the physical and biological effectiveness of stream habitat rehabilitation techniques
Authors: Roni, P., Hanson, K., & Beechie, T.
Journal: North American Journal of Fisheries Management
Year: 2008
DOI: https://doi.org/10.1577/M06-169.1
Species or groups: Cottonwoods, willows, tamarisks
Other sources of evidence: https://www.conservationevidence.com/actions/1228; https://www.conservationevidence.com/actions/1314
Abstract: The degradation of inland aquatic habitats caused by decades of human activities has led to
worldwide efforts to rehabilitate freshwater habitats for fisheries and aquatic resources. We reviewed
published evaluations of stream rehabilitation techniques from throughout the world, including studies on
road improvement, riparian rehabilitation, floodplain connectivity and rehabilitation, instream habitat
improvement, nutrient addition, and other, less-common techniques. We summarize current knowledge about
the effectiveness of these techniques for improving physical habitat and water quality and increasing fish and
biotic production. Despite locating 345 studies on effectiveness of stream rehabilitation, firm conclusions
about many specific techniques were difficult to make because of the limited information provided on
physical habitat, water quality, and biota and because of the short duration and limited scope of most
published evaluations. Reconnection of isolated habitats, floodplain rehabilitation, and instream habitat
improvement have, however, proven effective for improving habitat and increasing local fish abundance
under many circumstances. Techniques such as riparian rehabilitation, road improvements (sediment
reduction), dam removal, and restoration of natural flood regimes have shown promise for restoring natural
processes that create and maintain habitats, but no long-term studies documenting their success have yet been
published. Our review demonstrates that the failure of many rehabilitation projects to achieve objectives is
attributable to inadequate assessment of historic conditions and factors limiting biotic production; poor
understanding of watershed-scale processes that influence localized projects; and monitoring at inappropriate
spatial and temporal scales. We suggest an interim approach to sequencing rehabilitation projects that partially
addresses these needs through protecting high-quality habitats and restoring connectivity and watershed
processes before implementing instream habitat improvement projects.
Assessment of reliability and robustness (CEESAT)
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Smith, R.K., & Sutherland, W.J. (2014)
Amphibian conservation: Global evidence for the effects of interventions
Title: Amphibian conservation: Global evidence for the effects of interventions
Authors: Smith, R.K., & Sutherland, W.J.
Journal: NA
Year: 2014
DOI: NA
Species or groups: Natterjack toad, Oregon spotted frogs
Other sources of evidence: https://www.conservationevidence.com/actions/823
Abstract: NA
Assessment of reliability and robustness (CEESAT)
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Menninger, H. (2011)
A review of the science and management of Eurasian watermilfoil: Recommendations for future action in New York State. New York State Invasive Species Institute Final Report.
Title: A review of the science and management of Eurasian watermilfoil: Recommendations for future action in New York State. New York State Invasive Species Institute Final Report.
Authors: Menninger, H.
Journal: NA
Year: 2011
DOI: NA
Species or groups: Eurasian watermilfoil
Other sources of evidence: https://www.conservationevidence.com/actions/1228
Abstract: Key findings and recommendations:
EWM continues to infest and spread through the waters of New York State, despite significant
expenditures for management and control.
At best, physical, chemical, and mechanical management approaches reduce EWM over the short‐
term (up to a few years) and require a sustained and long‐term commitment for maintenance
control.
Biological control holds promise for long‐term EWM suppression, but research on the effectiveness
of commercial weevil augmentation practices has rarely been evaluated and published in the peer‐
reviewed scientific literature.
Research evaluating the outcomes of EWM management often lacks the scientific rigor to assess the
effects of multiple interventions applied over time or to understand the long‐term dynamics of
EWM populations left unmanaged.
Rather than continue the cycle of investment in ineffective maintenance control, New York State
should prioritize resources towards the development of a landscape‐level spread prevention
strategy.
Assessment of reliability and robustness (CEESAT)
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Thouvenot, L., Haury, J., & Thiebaut, G. (2013)
A success story: water primroses, aquatic plant pests
Title: A success story: water primroses, aquatic plant pests
Authors: Thouvenot, L., Haury, J., & Thiebaut, G.
Journal: Aquatic Conservation: Marine and Freshwater Ecosystems
Year: 2013
DOI: https://doi.org/10.1002/aqc.2387
Species or groups: Water primroses, Ludwigia grandiflora
Other sources of evidence: https://www.conservationevidence.com/actions/1135; https://www.conservationevidence.com/actions/1140; https://www.conservationevidence.com/actions/1138
Abstract: 1. Aquatic ecosystems are currently invaded by non-indigenous aquatic plants. A major challenge for biological
invasion research is to develop the ability to predict the spread of species.
2. Throughout the world, Ludwigia peploides subsp. montevidensis and Ludwigia grandiflora subsp. hexapetala
are now considered to be two of the most invasive aquatic plants. This paper reviews the scientific knowledge
about these species, their ecological and socio-economic impacts and methods of management.
3. Water primrose possesses some advantageous biological traits, such as rapid growth rate, efficient
reproductive capacity, high plasticity in growth response, broad ecological tolerance and allelopathic
compounds which might explain its expansion and colonization of numerous ecosystems.
4. Much attention must be paid to Ludwigia grandiflora subsp. hexapetala and Ludwigia peploides subsp.
montevidensis. According to climatic models, global warming will further increase the spread of these species
in Europe.
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Madsen, J.D. (2000)
Advantages and disadvantages of aquatic plant management techniques
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Murphy, K.J. (1988)
Aquatic weed problems and their management: a review. II. Physical control measures
Title: Aquatic weed problems and their management: a review. II. Physical control measures
Authors: Murphy, K.J.
Journal: Crop Protection
Year: 1988
DOI: https://doi.org/10.1016/0261-2194(88)90075-0
Species or groups: Aquatic weeds
Other sources of evidence: https://www.conservationevidence.com/actions/1228
Abstract: This review considers the wide range of aquatic plant management techniques which
fall under the heading of physical control. On a worldwide basis, physical control methods
remain the most widespread means of managing aquatic weed problems. Manual and mechanical
cutting and clearance are the commonest approaches, using tools ranging from simple scythes
and similar implements, to large complex aquatic weed harvester machines. Habitat manipulation
techniques are gaining thvour: such approaches reduce the plant productivity of the system by
increasing the level of natural stress and disturbance pressures acting on aquatic plant growth in
the freshwater habitat. Techniques include water level manipulation, reduction of light availability,
and a range of other physical and chemical habitat alteration procedures. Quarantine and
prevention measures may have a limited role in reducing the rate of spread of aggressive invading
aquatic weeds. The epidemic-wave model of aquatic weed invasions is discussed. The question of
whether active weed control programmes may actually hinder the suppression of such weed
problems, by interfering with natural mechanisms of environmental suppression of plant growth,
is considered. Methods of utilizing aquatic weeds, with the aim of turning a problem into a
resource, are examined. Future research strategies should involve aquatic weed ecology and
physiology, alongside studies aimed at technological improvements, in order to target improved
control measures against vulnerable stages in the weed life-cycle, while minimizing habitat
disruption for non-target components of the freshwater ecosystem.
Assessment of reliability and robustness (CEESAT)
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Moreira, I., Ferreira, T., Monteiro, A., Catarino, L., & Vasconcelos, T. (1999)
Aquatic weeds and their management in Portugal: insights and the international context
Title: Aquatic weeds and their management in Portugal: insights and the international context
Authors: Moreira, I., Ferreira, T., Monteiro, A., Catarino, L., & Vasconcelos, T.
Journal: NA
Year: 1999
DOI: https://doi.org/10.1007/978-94-017-0922-4_32
Species or groups: Aquatic weeds
Other sources of evidence: https://www.conservationevidence.com/actions/1228
Abstract: A historical insight into the connections between Portuguese researchers working on aquatic weeds and the EWRS Symposia (1964–1998) is given. A review is provided of the major aquatic weeds in Portuguese waters, including fluvial systems, reservoirs, drainage and irrigation canals, and rice fields along with the types of control and aquatic plant management practised in Portugal. Aquatic weed control in Portuguese waters is performed mostly by mechanical means, in spite of several experimental attempts at chemical control and biological control with fish and insects. Aquatic weed studies in other Mediterranean countries are also referred to.
Assessment of reliability and robustness (CEESAT)
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Cilliers, C.J., Hill, M.P., Ogwang, J.A., & Ajuonu, O. (2003)
Aquatic weeds in Africa and their control
Title: Aquatic weeds in Africa and their control
Authors: Cilliers, C.J., Hill, M.P., Ogwang, J.A., & Ajuonu, O.
Journal: NA
Year: 2003
DOI: NA
Species or groups: Aquatic weeds: water hyacinth, Eichhornia crassipes (Mart.)
Solms-Laubach (Pontederiaceae); red water fern, Azolla filiculoides Lam.
(Azollaceae); parrot’s feather, Myriophyllum aquaticum (Vell.) Verdc.
(Haloragaceae); water lettuce, Pistia stratiotes L. (Araceae); and salvinia,
Salvinia molesta Mitchell (Salviniaceae)
Other sources of evidence: https://www.conservationevidence.com/actions/1229
Abstract: NA
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Tanveer, A., Ali, H.H., Manalil, S., Raza, A., & Chauhan, B.S. (2018)
Eco-biology and management of Alligator Weed [Alternanthera philoxeroides)(Mart.) Griseb.]: a review
Title: Eco-biology and management of Alligator Weed [Alternanthera philoxeroides)(Mart.) Griseb.]: a review
Authors: Tanveer, A., Ali, H.H., Manalil, S., Raza, A., & Chauhan, B.S.
Journal: Wetlands
Year: 2018
DOI: https://doi.org/10.1007/s13157-018-1062-1
Species or groups: Alligator Weed
Other sources of evidence: https://www.conservationevidence.com/actions/1228
Abstract: Exotic plant invasion, a global issue, has a tremendous impact on ecology, economy, human, and animal health. Alligator weed (the world’s first aquatic weed) is a serious invasive weed in 32 different countries of South America, Australia, Asia, and North America. Recently, it has been recorded as a threat weed of rice, maize, soybean, vegetables, fruit trees, and pastures, causing 19–45% yield losses in these crops in addition to its infestation in canals, lakes, and ditches. Alligator weed has the potential to ruin agricultural and natural ecosystems and recreational areas. Ability to propagate via vegetative fragmentation, water-borne dispersal of vegetative propagules, and allelopathic potential contribute towards its success as an invasive weed species of terrestrial, semi-aquatic, and aquatic environments. Application of glyphosate, metsulfuron-methyl, dichlobenil, fluridone, hexazinone, triclopyr amine, dimethylamine, imazapyr, diuron, and amitrole herbicides have been found most effective in controlling this weed in different habitats. Agasicles hygrophila, Vogtia malloi pastana, Amynothrips andersoni, and Nimbya alternanthera have been reported as bio-agents for the control of alligator weed. We present a comprehensive review of the biology, interference, and management options of an extremely dangerous invasive weed species. Although management of alligator weed through chemical, biological, and mechanical means are often effective, there is need for well-planned, long-term field experiments to evaluate the role of different factors that are stated to be responsible for its increasing infestation and distribution (e.g., regeneration after damage caused by herbicides, high soil fertility levels, soil disturbances, shallow vs. deep ploughing and grazing management). It is recommended that future research should focus more on the integration of different management approaches in both aquatic and terrestrial ecosystems, and in various ecological regions.
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Escobar L.E., Mallez S., McCartney M., Lee C., Zielinski D.P., Ghosal R., Bajer P.G., Wagner C., Nash B., Tomamichel M., Venturelli P., Mathai P.P., Kokotovich A., Escobar-Dodero J., & Phelps., N.B.D. (2017)
Aquatic invasive species in the Great Lakes Region: An overview.
Title: Aquatic invasive species in the Great Lakes Region: An overview.
Authors: Escobar L.E., Mallez S., McCartney M., Lee C., Zielinski D.P., Ghosal R., Bajer P.G., Wagner C., Nash B., Tomamichel M., Venturelli P., Mathai P.P., Kokotovich A., Escobar-Dodero J., & Phelps., N.B.D.
Journal: Reviews in Fisheries Science & Aquaculture
Year: 2017
DOI: https://doi.org/10.1080/23308249.2017.1363715
Species or groups: Starry stonewart
Other sources of evidence: https://www.conservationevidence.com/actions/1228
Abstract: Aquatic invasive species (AIS) are of concern in North America due to their devastating impacts on
ecosystems and economies. The Great Lakes region is particularly vulnerable to AIS introduction
and establishment with at least 184 nonindigenous species reported in this region from a large
number of taxa including viruses, bacteria, diatoms, protozoa, arthropods, mollusks, fish, and plants.
Representative species from these groups were explored, describing the features of their natural
history and current efforts in prevention and control. Specifically, five AIS that are expected to
spread to novel areas in the region are discussed: viral hemorrhagic septicemia virus and
heterosporis (pathogens affecting fish), starry stonewort (an alga), zebra mussels (a bivalve), and
carps (fishes). Novel strategies for AIS control include next-generation sequencing technologies,
gene editing, mathematical modeling, risk assessment, microbiome studies for biological control,
and human-dimension studies to address tensions related to AIS management. Currently, AIS
research is evolving to adapt to known technologies and develop novel technologies to understand
and prevent AIS spread. It was found that AIS control in this region requires a multidisciplinary
approach focusing on the life history of the species (e.g., pheromones), adaptive management of
anthropogenic structures (e.g., bubble curtains), and the integration of human dimensions to
develop efficient management plans that integrate local citizens and management agencies.
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McFarland, D.G., Nelson, L.S., Grodowitz, M.J., Smart, R.M., & Owens, C.S. (2004)
Salvinia molesta D.S. Mitchell (Giant Salvinia) in the United States: A review of species ecology and approaches to management
Title: Salvinia molesta D.S. Mitchell (Giant Salvinia) in the United States: A review of species ecology and approaches to management
Authors: McFarland, D.G., Nelson, L.S., Grodowitz, M.J., Smart, R.M., & Owens, C.S.
Journal: NA
Year: 2004
DOI: NA
Species or groups: Giant salvinia
Other sources of evidence: https://www.conservationevidence.com/actions/1228
Abstract: Over the past 70 years, the free-floating aquatic fern Salvinia molesta D.S. Mitchell (giant salvinia) has spread from its native range in Brazil to many tropical and subtropical regions. Though innocuous within its native range, elsewhere this species is an aggressive menace that has had devastating ecological and socioeconomic impacts on aquatic systems in parts of Africa, Sri Lanka, India, Australia, New Guinea, and the Philippines. In the United States, the plant is established in waterways in at least 10 states (mainly in the south) and is expected to continue to expand in areas generally where Eichhornia crassipes (Mart.) Solms (water hyacinth) persists. Listed as a Federal Noxious Weed since 1984, S. molesta is prohibited from importation to the United States and from transport across state lines. Dense mats of S. molesta can suppress growth of native vegetation and degrade water quality, fish and wildlife habitat, and numerous other ecological values. Notably, massive infestations have occurred in the Swinney Marsh Complex, Texas, in the Lower Colorado River, Arizona/California, and in Lake Wilson and Enhanced Lake, Hawaii. This report presents a review of available information on the growth, distribution, and ecology of S. molesta. Information is provided on the plant's taxonomic status, its field characteristics, phenology, and spread overseas and in the United States. Growth responses of S. molesta in relation to environmental variables (e.g., temperature, nutrients, light, pH, conductivity) are emphasized as are impacts of the species on the environment and other aquatic organisms. Different technologies (i.e., physical, chemical, biological, and integrated) applied to control S. molesta infestations are discussed along with information on the effectiveness of these procedures and their need for further study.
Assessment of reliability and robustness (CEESAT)
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Assessment of relevance to Canada (RASCAT)
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Hummel, M., & Kiviat, E. (2004)
Review of world literature on the water chestnut with implications for management in North America
Title: Review of world literature on the water chestnut with implications for management in North America
Authors: Hummel, M., & Kiviat, E.
Journal: Journal of Aquatic Plant Management
Year: 2004
DOI: NA
Species or groups: Water chestnut
Other sources of evidence: https://www.conservationevidence.com/actions/1228
Abstract: Water chestnut (Trapa natans L., sensu lato) is an annual,
floating-leaved aquatic plant of temperate and tropical freshwater
wetlands, rivers, lakes, ponds, and estuaries. Native to
Eurasia and Africa, water chestnut has been widely gathered
for its large nutritious seed since the Neolithic and is cultivated
for food in Asia. Water chestnut is now a species of conservation
concern in Europe and Russia. Introduced to the
northeastern United States in the mid-1800s, the spread of
water chestnut as a nuisance weed was apparently favored by
cultural eutrophication. Water chestnut is considered a pest
in the U.S. because it forms extensive, dense beds in lakes,
rivers, and freshwater-tidal habitats. This results in displacement
of submergent aquatic plants, interference with boating,
fishing, and swimming, and depletion of dissolved
oxygen which adversely affects fish communities. Dry weight
phytomass ca. 100 to 1500 g/m
-2
has been reported in native
and introduced ranges. Water chestnut beds in the freshwater-
tidal Hudson River support substantial phytophilous
macroinvertebrate communities and a few species of small
fishes. Larger fishes forage at edges of beds and penetrate into
beds during favorable conditions, while birds forage on
top of beds and rodents eat the seeds. Herbicides and manual
or mechanical harvesting have been used for control.
There has been no comparative study of water chestnut in
native and introduced ranges, nor has the human food potential
been investigated in the United States. Harvest of water
chestnut for food, or for energy, might be compatible
with local management for fish habitat and recreation.
Assessment of reliability and robustness (CEESAT)
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Assessment of relevance to Canada (RASCAT)
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Hussner, A., Stiers, I., Verhofstad, M.J.J.M., Bakker, E.S., Grutters, B.M.C., Haury, J., Van Valkenburg, J.L.C.H., Brundu, G., Newman, J., Clayton, J.S., & Anderson, L.W.J. (2017)
Management and control methods of invasive alien freshwater aquatic plants: a review
Title: Management and control methods of invasive alien freshwater aquatic plants: a review
Authors: Hussner, A., Stiers, I., Verhofstad, M.J.J.M., Bakker, E.S., Grutters, B.M.C., Haury, J., Van Valkenburg, J.L.C.H., Brundu, G., Newman, J., Clayton, J.S., & Anderson, L.W.J.
Journal: Aquatic Botany
Year: 2017
DOI: https://doi.org/10.1016/j.aquabot.2016.08.002
Species or groups: Introduced invasive alien aquatic plants
Other sources of evidence: https://www.conservationevidence.com/actions/1228
Abstract: Introduced invasive alien aquatic plants (IAAPs) threaten ecosystems due to their excessive growth and have both ecological and economic impacts. To minimize these impacts, effective management of IAAPs is required according to national or international laws and regulations (e.g. the new EU regulation 1143/2014). Prevention of the introduction of IAAPs is considered the most cost effective management option. If/when prevention fails, early detection and rapid response increases the likelihood of eradication of the IAAPs and can minimize on-going management costs. For effective weed control (eradication and/or reduction), a variety of management techniques may be used. The goal or outcome of management interventions may vary depending on the site (i.e. a single waterbody, or a region with multiple waterbodies) and the feasibility of achieving the goal with the tools or methods available. Broadly defined management goals fall into three different categories of, containment, reduction or nuisance control and eradication. Management of IAAP utilises a range of control methods, either alone or in combination, to achieve a successful outcome. Here we review the biological, chemical and mechanical control methods for IAAPs, with a focus on the temperate and subtropical regions of the world and provide a management diagram illustrating the relationships between the state of the ecosystem, the management goals, outcomes and tools.
Assessment of reliability and robustness (CEESAT)
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Assessment of relevance to Canada (RASCAT)
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