Invasive Species

Seekiefer (Pinus halepensis) 9months-fromtop.jpg
This conservation resource was created by Micaela Anguita, Jonathan Kwok, Jordan Lum-Tong, Jaylen Bastos.


Japanese Knotweed growing at the museum-railway Beekbergen in The Netherlands. A plant originally from Japan, it has spread throughout the world and is infamous for causing infrastructure damage. Jaap Tamminga. CC BY 3.0 NL, via Wikiemedia Commons

Invasive species are non-native plants, often introduced by humans, that are capable of spreading and have negative effects on human health, the economy, and the ecosystems which they invade. Invasive species can cause infrastructure damage and they are notorious for damaging the agricultural industry. The development of globalization has increased the pathways and ease by which invasive species can spread into areas. Due to this increased influx, the damage caused by these species is starting to be noticed on a larger scale and steps are being taken in order to manage this damage. To combat the effects of invasive species, countermeasures will need to be implemented which are specifically designed to tackle this problem. Ecosystem management of urban and rural areas is essential for maintaining biodiversity of local and neighbouring environments. The absence of sufficient management, has resulted in the widespread introduction of invasive species. In addition to the establishment of invasive species within our natural and agricultural systems, urban areas have witnessed an increase in non-native species populations. Many counter measures exist but some are essential for successful management of invasive species. Four essential countermeasures that can be applied to aid the management process are (1) Databases of weeding techniques and their effects on local/adjacent ecosystems should be available to the general public as the primary countermeasure (2) current legislation, policies and regulations must be created and implemented to respond to the present day dynamics of invasive species management. Strict enforcement by an assigned agency, with penalties for non-compliance, will prove essential to the success of these regulations (3) a structured decision making plan that encompasses stakeholders’ key concerns, converted to key objectives is needed. Taking into account stakeholders allows them to assist through funds and activities for invasive species management. (4) prevention of introduction, pertains to the entering, establishing, and spreading of non-native species across an area. The management of introductory pathways, establishment promoting agents, and vectors of entry are the most effective preventative measures with regard to invasive management. These counter-measures against non-native invasive species are independently successful. However, it is in their combination that long term mitigation can be achieved.

The main concern with non-native invasive species is knowing how to get rid of them and knowing how to prevent further spread and growth. The responsibility not only falls on those who work in the weeding and restoration industry, but to society as this issue involves everyone and there is strength in numbers. Before the public can act towards elimination and prevention, information on assessing and controlling non-native invasive species can be hard to retrieve as well as understanding it. Most of the data on plant species is restricted in scholarly journals which only selected few can access without subscription payment, or private company and government databases which may not be disclosed to the public due to politics and laws on information copyright.[1]. The information that might already be public may not be used correctly. This can be an issue; if people are given false or misleading information on how to approach a plant species, the handler could be injured (if the plant were to be toxic) or the handler could further damage the surrounding environment by destroying native plant species or failing to dispose the invasive plant. As a result, a study was done showing that less than 20% of a population sample could not identify their local invasive species [2]. In the case of removing non-native invasive species and preventing their distribution, the availability and appropriateness of data can be an effective counter-measure against their spread.

As information on non-native invasive species grow, experts suggest possible sources to distribute knowledge, educate, and to raise awareness: government authorities, media outlets, environmental scholars, and word-of-mouth[2]. Those sources are important since they are in constant relations with the municipal community, extending to a greater population. What they have in common is that those source distribution can be placed on a platform available to most of society, the internet. This option of informing the public has potential since there can be a broad range of sources and authors producing information on invasive species. The draw back is that submission of information is not filtered nor entirely correct information, such as secondary sources. This leads to biases as well as misinterpretation from the public. Though there might be misinterpretation, a study has shown that sources from the local government, control companies (companies involved in invasive species removal), and media reports were searched more frequently[2]. It can be inferred that the population is well-aware of knowing where to seek information on invasive species. Knowing where to receive information is one matter, but knowing whether the information is correct is another issue that must be addressed.

A way to approach the problem of knowing whether the data is appropriate, as well as creating data available to everyone, is to tag and locate individual databases on invasive species throughout the internet, and to link them all in one collective database. This will act as a search engine as well as a server holding all knowledge on invasive species. This method of a collective database (meta-database), will allow not only the public to use, but for researchers to analyze and study different information on species[1]. Information can range from growth patterns, range distribution, biology, and tolerances and intolerances. This amount of information can easily be beneficial since there will be useful and important data to educate the population, and all of the data gathered has been screened by the scientific community that linked all the databases, solving the issue on access of information and its appropriateness. From this method of creating a database available to everyone, as well knowing that the information has been reviewed by the scientific community, the public will now have the suitable knowledge on approaching non-native invasive species, and learning how to further prevent its damage to nearby ecosystems.

Invasive species are quite dangerous, not just to urban areas, but to all areas of vegetation. By negatively affecting the amount of biodiversity, this could lead to the jeopardization of food security by affecting agricultural ecosystems[3]. Although the easiest way in theory is to completely eradicate the invasive species altogether, this is not as simple as it sounds. Due to the different variety of groups that are affected, such as the social, environmental and economic aspects, it takes a surprisingly long time to reach an agreement. Since they have been recognized as a key component in the decreasing of biodiversity, countermeasures need to be proposed and implemented to prevent the spread and harmful impact of invasive species to a halt.

Although there are many threats the are accustomed with invasive species, being able to set up a counter measure that includes the best interest of both stakeholders and the environment is the greatest way to please each group’s needs. The third counter-measure is a structured decision making plan that encompasses stakeholders’ key concerns, which are converted to key objectives. The major problem when properly deciding a counter measure are the different variables in which one must incorporate. When trying to deal with invasive species, decision making and conflict management are key, which are “…characterized by not only technical, but also environmental, social and economic value judgements of different stakeholders”. Although the ec[4] Economic value plays a pivotal role in each counter-measure, the social and environmental groups are not to be left out, as they play key roles in how the smooth the process will be accepted. By implementing a structured decision making plan, it will allow stakeholders to assist through funds and activities for invasive species management, all while keeping their best interests.

Within this framework, the first step is to recognize who the stakeholders are for the problem at hand and their ideals, and convert their major concerns into the key management ideals and goals for the management of response. This step is important due to the reliance of the counter measure relying on the participation of these key figures. It is also important to integrate the social aspect of this measure in order to give response alternatives and locate an option that is preferred by each party. Ultimately, this will lead to a decision which is most popular and has the least amount of overall negative trade-off from each group. Even though it is very important for variables such as the social aspect to be incorporated into this plan, the economic contributions from stakeholders are key to be able to carry out any strategy to properly deal with invasive species. This countermeasure is necessary to contain invasive species because even though there are other means of containing non-native plant species, the economic value that stakeholders hold is crucial to carry out any counter-measure. This step by step process ensures that the ideals of the stakeholders are met without cutting out the ideals of other important groups. Although there are many ways to go about handling invasive species, without the funds to support the initiative, those plans cannot be carried out properly.

There are currently many legislations and policies regarding invasive species worldwide. What seems to occur is that these may overlap with some from other areas, either contradicting them or diminishing their power [5]. This leads to confusion and often gridlock on the enforcement of either legislation or policy. The cross-jurisdictional weak links created by the contradiction of regulations in several jurisdictions of a large area can become compounded [6]. Leading to a regionally wide risk of invasive species introduction, the opposite of what is hoped to be achieved. In order to control and manage invasive species, all government levels in an area have to have regulations which agree with each other. This creates an overarching framework by which citizens, corporations, and governments can abide by. These regulations can come from previous ones which are re-formatted as long as they reflect successful management practices. This process is often lengthy and complex as it involves different levels of governance. Because of this complexity, regulations involving invasive species are seldom reformed or created, yet they are an essential component in the management of these types of species in order to reduce their negative impact on the environment and economy.

Populations of invasive species can be managed more effectively through eradication of new populations that are entering an area, therefore policies regarding the introduction of new species are important. These introduction pathways are mostly associated with human transportation of invasive species, for example trading ports, airports, highways etc. Most of the regulations regarding the introduction of invasive species then should be aimed at corporations and governments who provide the infrastructure through which invasive species are travelling through, and the users of said infrastructure[7]. Although there are trade-offs with these sort of regulations, it has been shown that it is economically preferable to regulate the introduction of invasive species before they reach an area rather than trying to manage a population once it has already been introduced [8]

Once a proper overarching framework of regulations regarding invasive species has been created, enforcement of these regulations must take place. Often, the gaps that are left between regulations and enforcement have lead to continuing damage to people and the environment at the hand of invasive species [9]. Enforcement should be lead by an assigned agency agreed upon when establishing the regulations. In order for this agency to enforce regulations appropriately, enough power must be given by the jurisdictions involved, otherwise their lack of power will render the enforcement useless. This agency is responsible for creating a framework on how penalties due to non-compliance of the regulations in place would be applied. The framework created must also include education to the public (including corporations) on what their responsibilities are when it comes to the introduction and management of invasive species. Too often an agency is not given the power to properly enforce regulations or the public is not informed on the legal implications of invasive species. The last step in making successful regulations to manage invasive species if for the enforcement of said regulations to be equal throughout all jurisdictions . This creates an equitable, collaborative process where regulations are enforced and the proper entities are penalized if needed.

Invasive species directly alter the integrity of natural ecosystems, consequently affecting societal values. Often resulting in increased management costs and lost resource productivity[10]. The establishment and spread of these individuals significantly threatens BC’s environment, society, and economy due to the pressures these species place on the aforementioned systems. The number of invasive species entering, establishing, and spreading across an area can be mitigated through preventative measures. Achieved through the management of introductory pathways and establishment promoting agents. In British Columbia, the diverse geographic and climate ranges provide a wide selection of pathways and vectors of entrance. Pathways are the geographic routing that facilitate the entry of invasive to British Columbia. Whereas vectors pertain to the the means by which invasive species from an external source population follow a pathway to a new destination[11]. Often vectors of entry are vehicles, including : boats, cars, planes, trains and animals. Anthropogenic entryways are most commonly associated with the transportation and importation of goods[12]. These entryways can intentionally introduce new species, as a planned import from another province or country. Adjacently however, these entryways may accidentally transport these species on vehicles or in shipping containers[13]. In contrast, natural vectors of spread consist of wildlife travel by way of migration, or forceful range expansion due to habitat destruction. Lastly, individual travel may also serve as a major vector for introduction due to the associated vehicles, pets, clothing, and footwear attributed to human travel. Prior to the implementation of prevention solutions, environmental considerations must be made as invasive species are under additional pressure from the changing climate. Climate change and global warming has shifted climatic envelopes and has resulted in warming trends and increased variation in weather patterns. These variations in natural systems are resulting in altered ecosystems that are favouring the success invasive species populations[14]. Enabling species to expand or shift their ranges beyond their natural range of occurrence. Therefore, an immediate challenge is to identify and manage both natural and human-caused invasion pathways and vectors, in response to the changing climate.

Hiking equipment is often the unknown carrier of invasive species. The Canadian Wildlife service has established several campaigns to educate hikers on cleaning their equipment to prevent the introduction of invasive species. Marc Levin. CC BY 2.0, via Flickr

The Canadian Wildlife service has outlined solutions, solving the problem of preventing invasive species establishment. These individual prevention solutions encompass a list of general recommendations that focus predominantly on the responsible and ethical treatment of natural resources [15].

  • The seeds and reproductive structures of invasive plants can be transported by residual mud and dirt. As such, try to clean the dirt from camping equipment, hiking boots or off of a vehicle before you leave an area..
  • Don’t bring animals, plants and agricultural products (fruits, vegetables, soil) into the country illegally. Especially when accessing vectors of travel associated with far distances (ie: planes).
  • Clean construction machines and equipment prior to leaving a job site. The mud and soil stuck to the machines are capable of harboring many seeds from invasive plants.
  • Avoid unnecessary disturbance of natural areas. Disturbing natural areas may increase the susceptibility of said area to an invasion by invasive species
  • Help out in your community. Join a local native plant organization or native fish or wildlife group.

In addition to these aforementioned solutions, the Government of British Columbia has outlined a prevention action plan, designed to prohibit the introduction and establishment of invasive species. The goal of this action plan is to engage citizens to undertake responsible action [16]

This will be achieved through:

  • implementation of their behaviour change strategy
  • fostering local and international partnerships
  • Obtaining the necessary resources to develop prevention infrastructure.
  • Formal recognition of positive actions

In collaboration with enhanced educational services in order to encourage and change public perception with regards to invasive species prevention[17]. As the persistence of invasive and exotic species continue to surpass the capabilities of local wildlife communities, to adapt, and respond to increased competition. Prevention of establishment vectors has become integral to secure the management of invasive species of British Columbia. Predominantly achieved through the implementation of behavioural change strategies, vehicular and individual travel management and the prevention of frivolous distribution [18].

A large majority of the commercial, agricultural, and recreational systems of British Columbia depend, in part, on healthy native ecosystems. These ecosystems are currently under threat by invasive species. Invasive species, bring one of the leading threats to the native wildlife and vegetation, have established and overtaken many of these integral ecosystems. Approximately 42% of threatened or endangered species are at risk primarily due to the influence and effect of invasive species on these ecosystems. The direct threats of invasive species are. preying on native species and out-competing native species for resources. These direct effects result in indirect changes to food webs. This may result in destroyed or depleted native food sources. Effectively decreasing species abundance and overall biodiversity. In addition to the natural degradation caused by these species, human health and economies are also at risk. The impacts of invasive species on our natural ecosystems and economy cost billions of dollars each year. In response to the damaging presence of invasive species, four countermeasures have been identified as being effective in the control and management of these species. Public availability of databases for weeding techniques can illustrate the effects of invasive species on local ecosystems. This countermeasure is a tool to educate and empower citizens to practice the responsible use of natural areas. In addition to public empowerment, legislation, policies and regulations must be created and implemented. These regulations must be current to be effective, and prove an important countermeasure in ensuring accountability amongst citizens and governments. Strict enforcement by an assigned agency, with penalties for non-compliance, will prove essential to the success invasive species management. Stakeholders’ key concerns, converted to key objectives must be outlined in a clear structured decision making plan. Facilitating stakeholder participation through financial support and actions for invasive species management. The final countermeasure, prevention, focuses on the restriction of transportation vectors of establishment. The aforementioned countermeasures have proven successful in their individual implementation throughout the province of British Columbia. However, it is in the collaboration of these countermeasures, that long lasting invasive species mitigation may be achieved.

  1. 1.01.1 Ricciardi, A. Steiner, W. Mack, R. N. Simberloff, D. 2000. Toward a Global Information System for Invasive Species. BioScience; 50 (3): 239-244. doi: 10.1641/0006-3568
  2. Robinson, B. S., Inger, R., Crowley, S. L., & Gaston, K. J. (2017). Weeds on the web: conflicting management advice about an invasive non-native plant. Journal Of Applied Ecology, 54(1), 178-187. doi:10.1111/1365-2664.12712
  3. Stokes, K. E. et al. “The Importance of Stakeholder Engagement in Invasive Species Management: A Cross-Jurisdictional Perspective in Ireland.” Biodiversity & Conservation 15.8 (2006): 2829–2852. Web
  4. Liu, Shuang, and David Cook. “Eradicate, Contain, or Live with It? Collaborating with Stakeholders to Evaluate Responses to Invasive Species.” Food Security 8.1 (2016): 49–59. Web.
  5. Invasive Species Council of BC. "Invasive Species Strategy for British Columbia". 2012.
  6. Gaertner, Mirijam et al. “Managing Invasive Species in Cities: A Framework from Cape Town, South Africa.” Landscape and Urban Planning 151 (2016): 1–9. ScienceDirect. Web.
  7. Simberloff, Daniel, Ingrid M. Parker, and Phyllis N. Windle. “Introduced Species Policy, Management, and Future Research Needs.” Frontiers in Ecology and the Environment 3.1 (2005): 12–20. Wiley Online Library. Web.
  8. Keller, Reuben P. et al. “Invasive Species in Europe: Ecology, Status, and Policy.” Environmental Sciences Europe 23.1 (2011): 23. Web.
  9. Simberloff, Daniel, Ingrid M. Parker, and Phyllis N. Windle. “Introduced Species Policy, Management, and Future Research Needs.” Frontiers in Ecology and the Environment 3.1 (2005): 12–20. Wiley Online Library. Web
  10. Invasive alien species framework for BC: identifying and addressing threats to biodiversity: a working document to address issues associated with biodiversity in British Columbia. Victoria, B.C.: Biodiversity Branch, Ministry of Water, Land and Air Protection, 2004. Print.
  11. MacNeely, Jeffrey A. Global strategy on invasive alien species. Gland: IUCN - The World Conservation Union, 2001. Print.
  12. Clements, David R., and S. J. Darbyshire. Invasive plants: inventories, strategies and action. Sainte-Anne-de-Bellevue, Que.: Canadian Weed Science Society, 2007. Print.
  13. Williamson, Mark. "Invasive species: vectors and management strategies." Diversity and Distributions 10.5-6 (2004): 508. Web
  14. Clements, David R., and S. J. Darbyshire. Invasive plants: inventories, strategies and action. Sainte-Anne-de-Bellevue, Que.: Canadian Weed Science Society, 2007. Print.
  15. An Action plan for wildlife habitat conservation: Canadian Wildlife Service. Ottawa: Environment Canada, Canadian Wildlife Service, 1992. Print.
  16. Darrigran, Gustavo, and Cristina Damborenea. "Strategies and Measures to Prevent Spread of Invasive Species." Limnoperna Fortunei (2015): 357-71. Web
  17. Invasive alien species framework for BC: identifying and addressing threats to biodiversity: a working document to address issues associated with biodiversity in British Columbia. Victoria, B.C.: Biodiversity Branch, Ministry of Water, Land and Air Protection, 2004. Print.
  18. An Action plan for wildlife habitat conservation: Canadian Wildlife Service. Ottawa: Environment Canada, Canadian Wildlife Service, 1992. Print.

Post image: Jonathan Billinger CC BY-SA 2.0 , via Wikimedia Commons