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Donaldson and Cooke Environ Evid (2016) 5:12
DOI 10.1186/s13750-016-0063-x
SYSTEMATIC REVIEW PROTOCOL
The eectiveness ofnon-native
sh eradication techniques infreshwater
ecosystems: a systematic review protocol
Lisa A. Donaldson1,2* and Steven J. Cooke1,2
Abstract
Background: This systematic review will address the need for having a better understanding of the evidence-base
for the effectiveness of different management techniques focussed on the eradication of non-native fish species in
the freshwater environment. Many resource management agencies around the world attempt to eradicate non-native
fish species to achieve management goals with respect to ecological integrity. There is a need to better understand
the effectiveness of each management technique to provide resource managers with the information necessary to
effectively manage aquatic resources, and to choose the best technique to yield desired outcomes given different
ecological and biological conditions. The findings of this systematic review will inform evidence-based manage-
ment and conservation activities for resource managers around the globe that deal with non-native fish eradication
programs.
Methods: This systematic review will search for, compile, summarize, and synthesize evidence on the effectiveness
of fisheries management techniques used for the eradication of non-native fish species in global freshwater systems.
The review will use public search engines and specialist websites, and will include both primary and grey literature.
All studies that assess the effectiveness of a fish eradication technique, in freshwater, will be included in the review.
Potential effect modifiers will be identified to obtain a better understanding of the factors that affect the success of
different eradication techniques, given different environmental conditions and biological factors. Study quality will be
assessed to allow for critical evaluation, including study design, confounding factors and statistical analysis. Data will
be compiled into a narrative synthesis and a meta-analysis will be conducted where data availability and quality allow.
Keywords: Alien invasive species, Removal, Restoration, Nonindigenous species, Invasive species, Invasion biology,
Evidence-based policy
© 2016 The Author(s). This article is distributed under the terms of the Creative Commons Attribution 4.0 International License
(http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium,
provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license,
and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/
publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
Background
In aquatic systems, biological invasions can result in
adverse ecological effects [1, 2]. Invasive species threaten
biodiversity [3–5] and impose considerable economic
costs [6], placing increased demands on policy-makers,
resource managers, and scientists [7]. e introduction
and spread of invasive species can occur by natural or
human pathways and can include: shipping networks and
canals [8, 9], escapes from aquaculture, aquaria and orna-
mental trade [10], stocking (including authorized and
unauthorized attempts), recreational boating, live food
trade, as well as sport fish and baitfish introductions,
which may be deliberate or accidental. Additionally, the
secondary spread of introduced species poses challenges
for resource managers [11–13].
Options for managing non-native fish species can
include no action, control and/or containment, popula-
tion extirpation, and/or species eradication [14]. Con-
tainment, such as implementing barriers, is typically
the most desirable tactic to prevent the spread of non-
native species into novel environments [15–18]. How-
ever, where containment is not possible or has not been
Open Access
Environmental Evidence
*Correspondence: Lisa.Donaldson@carleton.ca
1 Canadian Centre for Evidence-Based Conservation and Environmental
Management, Institute of Environmental Sciences, Carleton University,
1125 Colonel By Drive, Ottawa, ON, Canada
Full list of author information is available at the end of the article
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Donaldson and Cooke Environ Evid (2016) 5:12
successful, eradication has been proposed as a valid
option for managing biological invasions [19, 20]. Eradi-
cation is the elimination of whole fish populations or fish
species from distinct habitats or bodies of water [21].
Eradication approaches tend to be targeted, for example,
by exploiting vulnerable periods in the life cycle [22, 23]
or by focusing on areas of high abundance [24].
e types of fish management techniques available to
resource managers to implement eradication programs
can vary widely. ey can include chemicals, harvest
regimes, physical removal, or biological control [25]. e
effectiveness of chemical eradication (e.g., rotenone, Fin-
trol) depends on environmental conditions (e.g., water
temperature, depth, pH, discharge, target fish species,
hydrology, substrate composition, areas of groundwater
recharge; [26]); there are also concerns of collateral dam-
age when non-target species are affected by chemical
treatments [27]. Harvest regimes can include intentional
over-fishing (e.g., gill netting, angling) of target spe-
cies [28–30] or modification of angling regulations (e.g.,
favour overharvest of target species). Physical removal
techniques can include traps, electrofishing, and/or net-
ting programs while biological controls can include the
introduction of predators, intraspecific manipulation, or
targeted pathological reactions [31]. When implement-
ing fish management programs, risk analysis is required
to help decide when management strategies should be
utilized, what strategy should be chosen, and what the
likelihood of success of different strategies are [18]. e
risk analysis includes identification and assessments of
hazards, including predicting the likelihood and severity
of adverse effects [32].
e success of non-native fish management approaches
can vary greatly depending on the management objec-
tives for the project: whether control, eradication,
removal or containment (amongst others) was the ulti-
mate goal of the project. As can be expected given the
complexities of the natural environment, success can
be difficult to quantify and some approaches can be
unsuccessful despite best efforts [7, 19, 25]. Failure of
non-native fish eradication techniques can occur due to
a number of factors, including (but not limited to) inef-
fective capture techniques (e.g., size-specific efficiencies),
habitat complexity (e.g., areas of refuge, plant density),
species-specific factors (e.g., size, habitat preferences),
and physical water properties (e.g., water chemistry, tem-
perature, water depth; [33]). Determining the outcomes
of management interventions, especially when restora-
tion of freshwater ecosystems is a goal (i.e., to eradicate
non-native target fish species from a specific waterbody),
requires long-term evaluation and assessment in relation
to meeting the objectives [19, 25, 34]. Post-program eval-
uation and assessment is required not only to determine
the effectiveness of techniques but also to explore the
cost-effectiveness and cost/benefit of each strategy. Nar-
rative syntheses, meta-analyses and systematic reviews
can be valuable approaches to determine broad-scale
effectiveness of how management interventions can be
effective and to identify future research needs.
Objective ofthe review
e objective of the systematic review is to evaluate the
existing literature base to assess the effectiveness of dif-
ferent non-native fish eradication methods in global
freshwater environments. e purpose of the review is
not to question whether or not the eradication of a target
species is an appropriate objective, but simply to evalu-
ate the effectiveness of each technique for eradicating
the target species in a desired freshwater body (including
both lakes and rivers).
Primary question
What is the effectiveness of non-native fish eradication
techniques in freshwater ecosystems and what effects do
the various sources of potential heterogeneity have on
the outcome?
Components ofthe primary question
e primary study question can be broken down into the
study components:
Subject (population) Non-native freshwater fish
Intervention Fish eradication method
Comparator No intervention or alternative
method
Outcomes Magnitude of decreased
abundance relative to control
or eradication of target fish
species.
Secondary questions
Following the development of the primary question, sec-
ondary questions were developed to expand on relevant
areas of interest to project stakeholders and user groups,
including Canadian federal natural resources government
agencies (e.g., Parks Canada) and members of the inter-
national scientific community specializing in invasive fish
eradication science. e secondary questions are meant to
help guide the overall goals of the systematic review and to
ensure that areas of interest are encompassed in the meth-
ods. e secondary questions for this systematic review are:
(a) To what extent does effectiveness vary with eradica-
tion technique (e.g., electrofishing, piscicides, unlim-
ited recreational catch limits)?
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Donaldson and Cooke Environ Evid (2016) 5:12
(b) What other strategies/techniques are being employed
but are under-represented in the evidence and litera-
ture base?
(c) What factors (e.g., type and size of water body, spe-
cies, elevation, time since invasion/introduction,
ecoregion) influence the effectiveness of each type
of eradication method and in what context is each
technique most effective?
Methods
Details related to each step in the systematic review pro-
tocol are outlined in Fig.1.
Search strategy
Search terms
Similar to the way that the Review Team formulated
the primary and secondary questions, the Review Team
Fig. 1 Overview of steps in the proposed systematic review protocol
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Donaldson and Cooke Environ Evid (2016) 5:12
collaborated with project stakeholders (e.g., Parks Can-
ada) and members of the international scientific com-
munity specializing in invasive fish eradication science
to generate a list of relevant search terms (Table1). e
terms were broken into three components: population,
intervention and outcome.
e terms in each of the categories of population, inter-
vention and outcome can be combined using the Boolean
operators “OR” and/or “AND”, as suggested in the search
string. e asterisk (*) is a wildcard and represents any
characters (e.g., remov* includes remove, removal,
removing, removed) while the dollar sign ($) includes
zero or one character (e.g., rod$ and $reel includes rod-
and-reel, rod and reel). e terms are combined in the
following general format:
(Population)AND [(Intervention term)AND (Outcome term)]
[Fish* AND (Invasive OR Non$Native OR Alien OR
Exotic OR introduced OR non$indigenous OR IAS OR
Invasive$species OR Alien$invasive) AND (Fresh$water
OR Stream* OR Water* OR River* OR Lake* OR Reser-
voir* OR Pond* OR Canal* OR Harbor* OR Harbour* OR
Port* OR Wetland*)] AND [(Hyraulic OR Screen* OR
Weir* OR Net* OR Gill OR Trammel OR Hoop OR Trap
OR Cast OR Lift OR Seine* OR Trawl* OR Electrofish*
OR Electric OR Cull OR Piscicide* OR Rotenone OR
Antimycin OR Fintrol OR Explosive* OR Primacord OR
Biocide OR Angl* OR Trotline* OR “Rod-and-reel” OR
Limb$line* OR De$water OR Drawn&down OR Pump*)
AND (Restor* OR Rehabilitat* OR Remov* OR Eradicat*
OR Control* or Suppress* OR Reduc* OR Renovat* OR
Exclusion or Exclude*)].
Abbreviated search
When a complex search string is not accepted by the
search engine, the help menu will be consulted and the
search terms will be modified. e search terms will be
recorded in the article databases in order to preserve all
metadata associated with the search.
Article type
e search will include a variety of article types, includ-
ing primary literature in peer-reviewed journals and grey
literature. e search strategy will strive to minimize
publication biases by focussing efforts equally on each
article type and putting equal weight on the information
provided in each article type.
Document/le formats
e search will not have any document type restrictions
(e.g., PDF vs. MS-PowerPoint vs. MS-Word). All formats
will be acquired and if specialized software is required,
alternative formats will be requested for ease of file trans-
ferability. Where books are identified, digital copies will
be sought (either through internet searches for avail-
ability or requests to authors) in order to ensure that all
obtainable records are made available as an output from
this review.
Computer settings
e browsing history and cookies will be disabled on all
computers used to conduct the search. e members of
the Review Team will not access any electronic accounts
(e.g., email, website) during the search period and will
use “private mode” (Safari) for web browsers to reduce
the possibility of user-specific search results.
Language
English search terms will be used to conduct all searches
in all databases. All references that are returned will be
Table 1 Proposed search string for the execution of the
search strategy
Description Population Intervention Outcome
Question
elements Invasive sh Fish eradication
method Eradication
Synonyms and
permutations Fish* Hydraulic Restor*
Invasive Screen* Rehabilitat*
Non$native* Weir* Remov*
Alien Net* Eradicat*
Exotic Gill Control*
Introduced Trammel Suppress*
Non$indigenous Hoop Reduc*
IAS Trap Renovat*
Invasive$species Cast Exclusion
Alien$invasive Lift Exclude*
Fresh$water Seine
Stream* Trawl
Water* Electrofish*
River* Electric*
Lake* Cull
Reservoir* Piscicide*
Pond* Rotenone
Canal* Antimycin
Harbor* Fintrol
Harbour* Explosive*
Port* Primacord
Wetland* Biocide*
Angl*
Trotline*
Rod$and$reel
Limb$line*
De$water*
Draw$down
Pumping
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Donaldson and Cooke Environ Evid (2016) 5:12
included in the database. When articles in other lan-
guages are returned using the search strategy, those
records will be reported in the database.
Publication databases
1. Waves (Fisheries and Oceans Canada)—Canadian
government books, reports, government documents,
theses, conference proceedings and journal titles
2. Index to eses Online—Dissertations and theses
from the UK & Ireland
3. Science.gov—U.S. Federal Science
4. ISI Web of Science core collection—Multidiscipli-
nary research topics including journals, books, pro-
ceedings, published data sets, and patents
5. Scopus—Abstract and citation database of peer-
reviewed literature including journals, books, and
conference proceedings.
Search engines
e first 100 hits (based on relevance) will be examined
for the appropriate fit for the review questions.
6. Google Scholar.
Specialist websites
e first 50 documents from each search will be
included in the reference database and checked for
relevance. Reference lists of included material will be
searched and any relevant documents will be included
and added to the reference database. Where links to
other organisations are included on the websites, the
links will be followed to try to capture any organisations
that were not initially included in the website searches.
All articles will be exported into EndNote prior to
assessment of relevance.
7. Atlantic Salmon Federation
8. Centre for Ecology and Hydrology
9. Centre for Environment, Fisheries and Aquaculture
Science
10. Commonwealth Scientific and Industrial Research
Organisation
11. Convention on Biological Diversity
12. Department of the Environment, Food and Rural
Affairs
13. Desert Fishes Council
14. Fisheries and Oceans Canada
15. Fisheries Research Service
16. Food and Agriculture Organization of the United
Nations
17. Joint Nature Conservation Committee
18. National Institute of Water and Atmospheric Research
19. National Park Service
20. Natural England
21. Natural Resources Canada
22. Natural Resources Wales
23. Northern Ireland Environment Agency
24. Pacific Salmon Foundation
25. Parks Canada
26. Trout Unlimited
27. e Nature Conservancy
28. United Nations Environment Programme
29. US Forest Service
30. US Fish and Wildlife Service
31. Western Native Trout Initiative
32. World Wide Fund for Nature
33. World Wildlife Fund.
Other literature searches
Reference sections of accepted articles will be hand
searched to evaluate relevant titles, symposium papers,
and other articles that have not been found using the
search strategy. Authors of any unpublished references
will be contacted to request access to the full article.
Stakeholders will be consulted for insight and advice for
new sources of information.
e Review Team will contact authors of unobtainable
articles in an attempt to gain access to the full article. We
will also use social media to alert the community of this
systematic review and to reach out to area experts for
research articles that are difficult to obtain, or for sug-
gestions of articles to include. Any article provided will
also be used to test the comprehensiveness of our search
strategy and, where appropriate, adjustments will be
made to the search strategy to make sure it is compre-
hensive and inclusive. Any changes made to the search
strategy will be justified and documented in the final
review document.
Search record database
All articles generated by each of the search strate-
gies will be exported into separate EndNote databases.
After all searches have been completed and references
found using each different strategy have been compiled,
the individual databases will be merged into an overall
EndNote database library. Duplicates will be identified.
All references regardless of their perceived relevance to
this systematic review will be included in the database.
is database will act as the archive and will remain
unchanged throughout the review process, since it is the
direct product of the search strategy and will be useful in
the future when updating the systematic review archive
(general updating timeframe is currently every 5years).
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Donaldson and Cooke Environ Evid (2016) 5:12
Article screening andstudy inclusion criteria
Screening process andinclusion criteria
Articles found using the search criteria will be screened
in three distinct stages; title, abstract and full text.
Before the screening process begins, two review-
ers using a subset of 10% of all articles or 100 abstracts
(whichever is bigger) will undertake consistency checks
to ensure consistent and repeatable decisions are being
made in regards to which articles get screened out and
which go on in the process to be further reviewed. e
two reviewers will use a Kappa test to determine con-
sistencies in screening decisions. A Kappa score of ≥0.6
indicates substantial agreement between reviewers and
will be required to be achieved before any further screen-
ing is conducted for the review. e results from the con-
sistency check will be discussed and discrepancies will be
reviewed by both reviewers to understand why the choice
was made to include/exclude the article.
All article screening decisions will be included in the
database, so it will be clear at what level any article was
excluded. If the decision to include or exclude a specific
article is unclear, that article will be retained and will go on
to the next level of screening. If there is further doubt, the
Review Team will discuss those articles as a group to come
up with a decision. Any articles that do not have abstracts
(as is the case for some grey literature), those articles will
automatically be screened at the full text level. Justification
of the reason for inclusion or exclusion of an article will be
explained and recorded in the article database, and all arti-
cles excluded at the full text level will be included with the
review, in compliance with CEE guidelines.
Articles will be excluded based on the following pre-
defined inclusion criteria (Table2).
Study quality assessment
Each of the studies that make it to the full text screening
level will be classified and coded in the article database
using a number of parameters including (but not limited
to):
•Study setting—Lab or field
•Study design (BA/CI/BACI/RCT)
•Temporal extent of study
•Replication—Replicated or unreplicated
•Confounding factors—Present, not present, unclear,
and whether they were accounted for in the study
•Clarity of objectives in relation to methods used (e.g.,
is the ultimate type of management intervention
objective clearly identified, including eradication,
controlling, containing etc.)
•Use of (and number of) control and reference sites
•Effort devoted to eradication techniques (e.g., press
versus pulse, proportional area treated)
•Statistical methods used in assessment of success
(e.g., were results analysed statistically?)
•Accounting for and/or identifying potential effect
modifiers (see list in following sections).
Bilotta etal. [35] have outlined criteria for the assess-
ment of the internal validity of a study. eir assess-
ment criteria have been adapted from the Cochrane
Collaboration’s Risk of Bias Tool [36] for use in the
field of environmental science. e assessment criteria
include assessing selection bias, performance bias, attri-
tion bias, reporting bias, as well as those biases that may
only be relevant in unique situations (e.g., contamina-
tion). e criteria outlined in Bilotta etal. will be used
Table 2 Description ofinclusion criteria used bythe Review Team whenscreening articles atthe title andabstract level
Type ofcriteria Description ofinclusion criteria
Relevant subjects Freshwater ecosystems, including both lakes and rivers that contain non-native fish species
Relevant types of interventions Article describes the type of eradication method used in an attempt to eradicate a fish species. Eradication method
can include: mechanical, chemical, biological, environmental or other
Relevant types of comparators An external control site: similar waterbodies with no intervention (i.e., waterbodies with non-native fish present but
have not had any fish management projects conducted in them), before intervention control site within same
waterbody, or an alternative intervention type conducted on the same waterbody
Relevant types of outcomes Measured effect of treatment. Reported measured effect can be quantitative or observational and generally should
indicate some change in abundance of target species relative to before treatment or control
Relevant types of study designs Given the complexity of eradication projects, all types of study designs will be examined, including but not limited to:
Before/after (BA)
Comparator/intervention (CI)
Before/after/comparator/intervention (BACI)
Randomized controlled trial (RCT )
Studies that do not do or report any before or after assessments following the implementation of an eradication
effort will be excluded from the review (i.e., studies where no data is presented that would allow for any assessment
of a change in abundance of the target species following eradication efforts)
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Donaldson and Cooke Environ Evid (2016) 5:12
by the Review Team for this review and included in
the reference database. e information for each arti-
cle retrieved using the search strategy will be uniquely
coded based on the criteria (generally categorised as
“low risk”, “high risk”, or “unclear risk”) to help assess
the quality of each article, and to provide insight into
any potential risk of bias present in each of the stud-
ies. is information will be instrumental in helping to
determine reliability of the evidence base available for
potentially conducting a meta-analysis on the effective-
ness of each eradication method.
Data extraction strategy
Metadata will be extracted from the included studies by
the Review Team and will be recorded in a MS-Excel
database that will be made available with the published
systematic review article, as an additional supporting
file. e extracted information will be used to assess the
overall effectiveness of each intervention strategy, and
when sufficient, good quality data exists, the informa-
tion will be used in a meta-analysis. Some of the out-
come data that will be recorded will include: outcome
means, measures of variation (e.g., standard deviation,
standard error, confidence intervals), and sample sizes.
When data is presented in tables or graphs, all informa-
tion will be extracted and recorded. If it is not possible
to decipher information from graphs, the main contact
author for the article will be contacted (via email or
phone) by the Review Team to request the information.
During that request, the Review Team will also solicit
the author to suggest any grey literature that they may
know of related to the systematic review topic. Where
only raw data is provided in the article, the Review
Team will calculate summary statistics. In those
instances, it will be recorded in the MS-Excel database
how the calculations were done and with what informa-
tion. To ensure that data is being extracted in a consist-
ent and repeatable manner, two reviewers will extract
information from 10 of the same articles. Afterwards,
the information will be compared. Any inconsistencies
will be discussed amongst the Review Team members,
and if any disagreement occurs, they will be discussed
with the entire Review Team to ensure all reviewers are
extracting and interpreting data in the same manner.
Potential eect modiers andreasons forheterogeneity
e Review Team will extract data on potential effect
modifiers(see Table3) from articles that are included at
the full-text level of screening. All information will be
recorded in the MS-Excel database.
Table 3 presents the criteria that will be consid-
ered as potential effect modifiers and/or reasons for
Table 3 Data extraction table
Main category Sub-category Description
Article metadata Study ID Unique code given to each
study (i.e., linked articles
given same code)
Paper ID Unique code given to each
manuscript
Authors Name of authors
Email address All email address of main
contact
Publication year Year of manuscript publica-
tion
Title Article title
Reference Full reference (as extracted
from relevant database)
Publication type Publication format (e.g.,
book chapter, journal
paper, conference paper,
thesis, organisation
report)
Abstract Article abstract or summary
(if provided)
Keywords Publication keywords
Author affiliation type Author affiliation (e.g.,
academic institution,
government, consulting,
NGO)
Language
Article access notes Any issues associated with
accessing the full article
(e.g., were the authors
contacted?)
Format Article format e.g., PDF,
Microsoft Word file, HTML
Location meta-
data Study country Country(ies) in which study
undertaken
Study region Region(s) in which study
undertaken
Study type Lab or field-based
Study design BA/CI/BACI/RCT
Study waterbody Name of waterbodies
included in study
Latitude
Longitude
Location meta-
data UTM zone
UTM coordinates
Waterbody
metadata Waterbody type Lake, river, reservoir, pond
etc.
Waterbody area Record how it is reported in
the article, including units
Average depth
Volume
Area
Retention time
Secchi depth
Wetted width
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Donaldson and Cooke Environ Evid (2016) 5:12
Table 3 continued
Main category Sub-category Description
Stream order
Stream type E.g., permanent, intermit-
tent
pH
Turbidity
Water clarity/colour
Conductivity
Discharge
Water temperature
Canopy cover (%)
Slope (%)
Substrate composition E.g., silt, sand, gravel, cob-
ble, rubble, bedrock
Vectors for introduction If discussed in article
Open or closed system
Manmade or natural
system
Waterbody accessibility Easy (e.g., canal in city),
moderate (e.g., river in
national park), difficult
(e.g., high alpine lake)
History of biomanipula-
tion?
Extent population is
established If discussed in article
Target species
metadata Fish species name
Fish species scientific
name
Migratory or non-
migratory
Life history strategy E.g., anadromous, semelpa-
rous, iteroparous
Target age class
Habitat preferences
Age at maturity
Fecundity
Relative abundance of
target species (pre-
intervention)
Change in abundance of
target species, before
intervention (e.g., CPUE)
pH
DO range
Depth range
Body size
Habitat use
Intervention
metadata Date: project start dd-mmm-yy
Date: project end dd-mmm-yy
Study length Duration of study
Study timescale Period between interven-
tion and study
Pre-monitoring Was there any pre-monitor-
ing that occurred? If yes,
describe
Table 3 continued
Main category Sub-category Description
Post-monitoring Was there any post-mon-
itoring that occurred? If
yes, describe
Study seasonality What season did the study
take place? Describe all
if occurred over many
seasons
Study description Brief description of study
Eradication method
type Mechanical, chemical,
biological, environmental,
other
Eradication method
details Mechanical method type,
type of chemical used,
name of introduced
biological control etc.
Intervention
metadata Eradication effort Will vary depending on
method used (e.g., elec-
trofishing time, fishing
time, area treated)
Number of fish removed Report the total number
of fish removed. Can
separate number of fish
removed live versus dead,
depending on eradication
method type
Methodological detail Level of methodological
detail; low (very little
detail, significant informa-
tion missing), medium
(some detail missing but
generally sufficient), high
(very high level of detail,
no obvious information
lacking)
Methodology notes Brief description (summary
or quotation) of study
methodology
Intervention type
rationale How/why were the inter-
vention types selected?
Experimental design i.e., observation, experimen-
tation, modeled
Study cost If discussed in article
Replication Number of replicates, if
applicable
Randomization Presence of randomization,
if applicable
Sources of potential bias Description of other poten-
tial sources of bias
Outcome meta-
data Relative abundance of
target species (post-
intervention), over
time
Change in abundance of
target species, after inter-
vention (e.g., CPUE), over
time. Report the duration
that the abundance
was monitored for (e.g.,
1 week post intervention,
6 months, 1 year etc.)
Eradication probability If discussed in article
Change in species
composition If discussed in article, the
change in species com-
position in the waterbody
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Donaldson and Cooke Environ Evid (2016) 5:12
heterogeneity and will be extracted. Further factors may
be identified, defined and included throughout the pro-
cess, through consultation with external experts.
Data synthesis andpresentation
A narrative synthesis of data from all articles included
in the systematic review will be generated. e synthesis
will aim to be as visual as possible, summarizing informa-
tion in tables and figures. e ultimate goal of this review
is to assess the effectiveness of each different eradication
technique and to identify the factors that influence the
overall success rate of each type of method, in order to
better inform management agencies who routinely have
to decide when, where and how non-native fish eradica-
tion programs should be implemented. All efforts will be
made to provide quantitative assessments and meta-anal-
ysis of the articles included in this review, when the study
designs and evidence-base allow. e review team has
conducted some scoping exercises, particularly to help
develop an efficient search strategy and to get a sense of
the existing literature base. When doing so, the review
team got the sense that sufficient evidence may exist to
allow them to conduct a meta-analysis on some inter-
vention types, but it is unlikely that a meta-analysis may
be possible for all intervention types. It will also depend
on the literature base for each target species. Sufficient
evidence may exist for some more common target (prob-
lem) species but not for more regionally-relevant species.
Authors’ contributions
All authors participated in the drafting, revision, and approval of the manu-
script. Both authors read and approved the final manuscript.
Author details
1 Canadian Centre for Evidence-Based Conservation and Environmental
Management, Institute of Environmental Sciences, Carleton University, 1125
Colonel By Drive, Ottawa, ON, Canada. 2 Fish Ecology and Conservation Physi-
ology Laboratory, Department of Biology, Carleton University, 1125 Colonel By
Drive, Ottawa, ON, Canada.
Acknowledgements
The authors would like to thank several reviewers and collaborators who
provided valuable insights to strengthen this review protocol including:
Robert Britton (Bournemouth University, UK), David Browne (Canadian Wildlife
Federation, CA), Robert Gresswell (United States Geological Survey, USA), and
Mark Lintermans (University of Canberra, AU), and Parks Canada staff including
Kent Prior, Marlow Pellatt, Mark Taylor, Bill Hunt, Chantal Vis, Scott Parker, and
Shelley Humphries. The study was supported by Parks Canada, the Natural Sci-
ences and Engineering Research Council, the Canada Research Chairs Program
and the Carleton University Research Excellence Fund.
Competing interests
The authors declare that they have no competing interests.
Received: 19 January 2016 Accepted: 2 June 2016
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Table 3 continued
Main category Sub-category Description
Change in biomass of
target species
Change in size of target
species If discussed in article, the
change in target species
size over time, after eradi-
cation efforts (e.g., total
length, mass, proportion
of catch within a specific
size range)
Statistical results of
effectiveness measure Was the effectiveness
assessed statistically? If
yes, report
Social factors
metadata Social risk factors Did project consultation
occur for this project?
(Y/N)
Social risk factors—
Details If yes, describe (e.g., public
meetings, media released)
Linked article
metadata Linked study Paper ID of articles describ-
ing results of same study.
This is especially impor-
tant to look at overall suc-
cess rates for projects that
are reported over several
different publications
Additional article details Further description of
relationship with other
articles
Page 10 of 10
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