Subjects of justice: rethinking invasive weeds through multispecies justice – Nature

Report on Invasive Species Management and Sustainable Development Goals

Executive Summary

Invasive species are a primary driver of biodiversity loss, directly threatening the achievement of Sustainable Development Goal 15 (Life on Land). However, conventional management strategies, focused on eradication, often overlook the complex ecological roles these species play in highly modified urban and post-industrial environments. In these settings, which are central to SDG 11 (Sustainable Cities and Communities), invasive species can form novel ecosystems that provide critical services to other species. This report argues that current legislative and management frameworks are often too rigid and anthropocentric, failing to deliver just or effective outcomes. We propose the adoption of a Multi-Species Justice (MSJ) framework, a deliberative approach that extends the concept of justice to non-human species. This framework offers a path to renegotiate the tensions between native and invasive species, fostering urban environments that support multispecies flourishing and advance SDG 16 (Peace, Justice and Strong Institutions) through more inclusive and effective governance.

1.0 Introduction: The Global Biodiversity Crisis and Sustainable Development Goals

The planet is facing an unprecedented biodiversity crisis, undermining progress towards SDG 15 (Life on Land), which aims to halt biodiversity loss. This decline is driven by a range of interconnected anthropogenic pressures, exacerbated by climate change, which threatens SDG 13 (Climate Action). The primary drivers include:

• Habitat destruction and fragmentation
• Overexploitation of resources
• Pollution
• Climate Change
• Invasive alien species

Invasive plant species, introduced outside their natural range, are a significant factor in this crisis. They can alter community composition and ecosystem functions by outcompeting native flora, disrupting trophic interactions, and modifying ecological processes. Traditional conservation paradigms view invasive species as threats to be controlled or eradicated, a perspective that fails to capture the ecological complexity of species interactions, particularly in heavily modified urban landscapes.

2.0 The Role of Invasive Species in Urban Ecosystems

While the negative impacts of invasive species are well-documented, their role in urban and post-industrial environments requires a more nuanced assessment to align with the objectives of SDG 11 (Sustainable Cities and Communities). These landscapes often constitute novel ecosystems where conventional restoration is unfeasible.

2.1 Novel Ecosystems and Urban Sustainability

Novel ecosystems are fundamentally altered environments where abiotic, biotic, and social elements interact in new ways due to human influence. Cities, with their constant disturbance, altered soils, and fragmented habitats, are ideal settings for the emergence of these systems. Within these contexts:

• Invasive species can provide crucial ecosystem services, such as habitat and food resources for native fauna, where native plants may fail to persist.
• The indiscriminate removal of non-native species can lead to a net reduction in functional and species diversity, working against the goals of urban biodiversity enhancement.
• These landscapes become relational spaces rooted in complex legal, ethical, and political narratives of belonging, rather than simple ecological problems to be solved.

2.2 Case Study: Lantana camara in Sydney, Australia

Lantana camara (lantana), native to the Americas, is listed as one of the world’s worst invasive species. In Australia, it is classified as a “key threatening process.” However, in a degraded urban greenspace in Sydney known as ‘Glebe Hill’—a former landfill site—lantana plays a complex role. A recent ecological assessment revealed:

1. The site’s ecology is a hybrid, dominated by non-native plants (74%), including lantana.
2. This novel ecosystem supports a range of native fauna; the bird fauna is 75% native, and the invertebrate fauna is 67% native.
3. Dense thickets of lantana provide critical services, offering protection and resources for small native birds (e.g., Silvereyes) and invertebrates, which are often sensitive to urbanization.

This case demonstrates that removing lantana, as conventional policy would dictate, could inadvertently harm the very native biodiversity stakeholders wish to protect, highlighting a conflict with the practical achievement of SDG 15 targets in an urban context.

3.0 Governance and Management Frameworks in the Context of SDG 16

Current regulatory frameworks for managing invasive species often lack the flexibility to address the complexities of novel urban ecosystems, hindering the development of the effective and inclusive institutions called for by SDG 16 (Peace, Justice and Strong Institutions).

3.1 Legislative Shortcomings and Anthropocentric Bias

In Australia, national and state legislation categorizes lantana as a threat to be managed and eradicated. This legal framing is problematic for several reasons:

• It establishes a rigid, abstract native/non-native binary that is insensitive to local ecological context and function.
• It prioritizes certain species over others based on historically located human values, an inherently anthropocentric approach.
• The law “freezes” plants and animals in static categories, ignoring their agency and the dynamic nature of ecosystems.

3.2 The Need for Adaptive Management Aligned with Climate Action (SDG 13)

Climate change is predicted to increase the areas favorable for lantana, making eradication efforts even less feasible. The failure of traditional control methods, combined with the pressures of a changing climate, necessitates a paradigm shift in management. An adaptive approach that focuses on the function of species rather than their origin is required to build resilient urban ecosystems capable of meeting the challenges outlined in SDG 13.

4.0 A Multi-Species Justice Framework for Achieving the SDGs

To navigate the conflicts inherent in managing novel ecosystems, this report advocates for a Multi-Species Justice (MSJ) framework. MSJ expands traditional justice concepts to include non-human beings and ecological systems, promoting a more holistic approach to sustainability that integrates SDG 11, 15, and 16.

4.1 Principles of Multi-Species Justice (MSJ)

MSJ is a deliberative process and practice that is guided by the following principles:

1. Recognition: Acknowledging that all species and ecological communities are interconnected and have inherent value, treating them as subjects of justice rather than objects of human concern.
2. Relationality: Focusing on the relationships between beings and humanity’s disproportionate capacity to shape these relationships.
3. Representation: Developing inclusive decision-making processes that consider the needs and agency of non-human species, such as plants, animals, and ecosystems.
4. Deliberation: Creating a platform to critically reflect on the distribution of benefits and burdens among all stakeholders, both human and non-human, making power imbalances and unintended harms evident.

4.2 Aligning Invasive Species Management with SDGs

Applying an MSJ lens allows planners and managers to move beyond the native-invasive dichotomy and engage with the complexities of urban ecosystems. This approach directly supports key SDGs by:

• Fostering Sustainable Cities (SDG 11): By informing the management of urban green spaces to support the flourishing of all life, enhancing biodiversity and ecological resilience.
• Protecting Life on Land (SDG 15): By promoting evidence-based, context-specific management that can, counter-intuitively, enhance net biodiversity by recognizing the functional roles of so-called invasive species.
• Building Just Institutions (SDG 16): By creating more inclusive, equitable, and effective governance structures that account for the interests of all species affected by management decisions.

5.0 Recommendations and Conclusion

The management of invasive species in urban areas presents a significant challenge to achieving global sustainability targets. The simple binaries of native versus non-native are unfit for purpose in the complex, hybrid ecosystems that characterize modern cities. A paradigm shift is necessary.

This report concludes that a Multi-Species Justice framework provides a pragmatic and ethical path forward. We recommend that planners, environmental managers, ecologists, and policymakers:

1. Adopt a deliberative, MSJ-informed approach to urban green space management that considers all species as stakeholders.
2. Move away from rigid, eradication-focused policies toward evidence-based, adaptive strategies that assess species based on their ecological function within a specific context.
3. Revise regulatory frameworks to allow for place-sensitive management that recognizes the potential positive contributions of non-native species in degraded environments.
4. Foster partnerships between diverse fields and stakeholders, as envisioned in SDG 17 (Partnerships for the Goals), to co-create urban landscapes that are just and sustainable for all forms of life.

Analysis of Sustainable Development Goals in the Article

1. Which SDGs are addressed or connected to the issues highlighted in the article?

The article addresses several Sustainable Development Goals (SDGs) through its discussion on invasive species, biodiversity, urban ecosystems, and environmental governance. The primary SDGs connected to the article’s themes are:

1. SDG 15: Life on Land

   This is the most central SDG to the article. The text extensively discusses the threat of invasive species to native biodiversity, which is a core component of SDG 15. It highlights that “Invasive species are widely posited as a major threat to native biodiversity worldwide” and are a key driver of the “biodiversity and species extinction crisis.” The entire analysis of Lantana camara, its impact on native flora and fauna, and the legislative frameworks for its control directly relate to protecting terrestrial ecosystems.

2. SDG 11: Sustainable Cities and Communities

   The article specifically frames its analysis within “urban and post-industrial environments.” It uses the “Glebe Hill” urban green space in Sydney as a case study to explore the complex role of invasive species in cities. This connects to SDG 11’s goal of making cities inclusive, safe, resilient, and sustainable. The discussion on managing urban green spaces, the emergence of “novel ecosystems” in cities, and the need for new planning approaches for urban biodiversity are all relevant to this goal.

3. SDG 16: Peace, Justice and Strong Institutions

   The article’s proposal of a “multi-species justice (MSJ) framework” directly engages with themes of justice and inclusive decision-making, which are central to SDG 16. It critiques current regulatory frameworks as being “exceedingly anthropocentric” and argues for a “deliberative decision-making process” that extends justice to non-human species. The analysis of Australian legislation and the critique of the IPBES framework for excluding non-human “stakeholders” highlight the need for more just and inclusive institutions for environmental governance.

4. SDG 13: Climate Action

   The article links the problem of invasive species to climate change, noting that the threat is “exacerbated by anthropogenic climate change.” It explicitly states that the invasion risk of Lantana camara “will increase across all continents under global heating,” and that “future climate scenarios are predicted to increase the areas climatically favourable for lantana.” This connects the management of invasive species to climate change adaptation and policy integration, which are key aspects of SDG 13.

2. What specific targets under those SDGs can be identified based on the article’s content?

Based on the article’s detailed discussion, several specific SDG targets can be identified:

• Under SDG 15 (Life on Land):

  • Target 15.5: “Take urgent and significant action to reduce the degradation of natural habitats, halt the loss of biodiversity and, by 2020, protect and prevent the extinction of threatened species.” The article directly addresses this by describing how invasive species like lantana cause “displacement of native flora,” “declines in native fauna,” and “habitat degradation.” It mentions specific threatened species in NSW, such as the “Eastern Bristlebird and the Back Grass-Dart Butterfly,” whose survival is threatened by lantana.
  • Target 15.8: “By 2020, introduce measures to prevent the introduction and significantly reduce the impact of invasive alien species on land and water ecosystems and control or eradicate the priority species.” This target is a central theme. The article details the global challenge of managing Lantana camara, which is named “one of the 100 worst invasive alien species.” It discusses various control strategies (mechanical, chemical, biological) and the legislative measures in Australia designed to control its spread.
  • Target 15.9: “By 2030, integrate ecosystem and biodiversity values into national and local planning, development processes…” The article critiques the current “rigid and abstracted native/non-native binary categorisation” in planning and law. It advocates for the integration of more complex ecological values through the MSJ framework, especially in the management of urban green spaces like Glebe Hill.

• Under SDG 11 (Sustainable Cities and Communities):

  • Target 11.7: “By 2030, provide universal access to safe, inclusive and accessible, green and public spaces…” The case study of “Glebe Hill,” a “degraded and contaminated informal greenspace in Sydney,” is a direct example of the type of public space this target addresses. The article explores the challenges and opportunities in managing such spaces to support both biodiversity and community value.

• Under SDG 16 (Peace, Justice and Strong Institutions):

  • Target 16.7: “Ensure responsive, inclusive, participatory and representative decision-making at all levels.” The article’s core argument for a “multi-species justice (MSJ) framework” is a call to reform decision-making. It critiques the IPBES framework where “‘stakeholders’ are exclusively human” and advocates for a “deliberative framework” that includes “Earth others and their communities” as subjects of justice, thereby making the process more inclusive and representative of all affected beings.

• Under SDG 13 (Climate Action):

  • Target 13.2: “Integrate climate change measures into national policies, strategies and planning.” The article implies the need for this integration by highlighting that “future climate scenarios are predicted to increase the areas climatically favourable for lantana.” This suggests that any long-term national strategy for managing invasive species must account for the impacts of climate change.

3. Are there any indicators mentioned or implied in the article that can be used to measure progress towards the identified targets?

The article mentions or implies several qualitative and quantitative indicators that could be used to measure progress:

• For SDG Target 15.5 (Halt biodiversity loss):

  • Implied Indicator: Status of threatened species. The article names the “Eastern Bristlebird and the Back Grass-Dart Butterfly” as animals threatened by lantana. Tracking the population trends of these and other species affected by invasive plants would serve as a direct indicator of progress.
  • Implied Indicator: Measures of local biodiversity. The article discusses how the removal of invasive species can lead to a “reduction in both functional and species diversity.” In the Glebe Hill case study, it provides data on the composition of fauna (e.g., “bird fauna is primarily native (75%)”) and flora (“dominated by non-native plant species (74%)”). These metrics can be used as indicators of ecosystem health in novel urban environments.

• For SDG Target 15.8 (Control invasive alien species):

  • Indicator (corresponds to official indicator 15.8.1): Adoption of national legislation and strategies for the control of invasive species. The article explicitly mentions Australian national and state legislation, such as the “Biodiversity Conservation Act 2016 (NSW)” and the “Environmental Protection and Biodiversity Conservation Act 1999 (Cth),” as well as the “2017 – 2027 Australian Weeds Strategy.” The existence and implementation of these policies are direct indicators.
  • Implied Indicator: Geographic spread and cover of invasive species. The article references a study predicting that lantana will continue to spread with an “estimated cover of at least 68.98%” in certain regions. Monitoring the actual spread and density of lantana and other invasive species would be a key performance indicator for management effectiveness.

• For SDG Target 11.7 (Access to green spaces):

  • Implied Indicator: Quality and biodiversity value of urban green spaces. The article’s detailed ecological assessment of the 0.6-hectare “Glebe Hill” site—including its history as a landfill, its current plant and animal composition, and its function as a habitat—implies that progress should be measured not just by the quantity of green space, but by its ecological quality and its ability to support diverse life forms.

• For SDG Target 16.7 (Inclusive decision-making):

  • Implied Indicator: Extent of inclusion of non-anthropocentric values in environmental governance frameworks. The article critiques the IPBES report for its exclusively human-centric definition of “stakeholders.” An indicator of progress would be the formal integration of frameworks like MSJ into policy, where the interests and agency of non-human species are formally recognized and considered in environmental decision-making processes.

4. Table of SDGs, Targets, and Indicators

Source: nature.com