The current attention and traction of fauna-sensitive road design in Australian transport research: a systematic review

ABSTRACT

The implementation of fauna-sensitive road design has the potential to mitigate negative impacts on wildlife caused by roads. However, our previous international review found adoption of fauna-sensitive road design has been limited at the level of transport planning, even in nations that mandate this. In Australia, where the adoption of fauna-sensitive road design is still in its early stages, a review of 57 peer-reviewed papers revealed that transport practitioners generally have not acknowledged or considered fauna-sensitive road design measures or road ecology concepts. This lack of consideration is due to deeply rooted economic interests and attitudes institutionalised within the industry. While the development of fauna-sensitive road design is possible in the Australian transport sector, a substantial institutional change driven by appropriate policies and user experiences is necessary. We recommend future studies explore practitioner experience to better understand the conditions that facilitated the voluntary adoption of fauna-sensitive road design policies in two Australian states.

KEYWORDS:

• Road ecology
• fauna-sensitive road design
• linear transport infrastructure
• sustainable development
• transport policy

1. Rationale

The evolving discipline of road ecology, encompassing the study of various road elements such as vehicles, soil, water, air, plants and wildlife, strives to mitigate the adverse impacts of linear transport infrastructure on fauna (van der Ree, Smith, and Grilo 2015). In parallel, endeavours to address the impact of linear transport infrastructure on wildlife have given rise to the widespread adoption of fauna-sensitive road design (FSRD) – green infrastructure that integrates diverse wildlife crossing structures, including ecoducts, land/green bridges, wildlife overpasses, canopy bridges, glider poles, underpasses and modified culverts, to facilitate safe wildlife movement across fragmented habitats intersected by linear transport infrastructure. Demonstrating effectiveness globally, these structures are designed not only to sustain landscape connectivity but also to enhance road safety, reducing wildlife-traffic collisions and associated costs (Jones et al. 2011; Jones and Pickvance 2013; Wilson, Marsh, and Winter 2007). Consequently, this has stimulated the implementation of policy measures such as green networks, wildlife corridors and defragmentation programmes, particularly within European Union member states (Damarad and Bekker 2003; Iuell 2003; van der Ree, Smith, and Grilo 2015).

The implementation of these frameworks has sparked notable research interest, evident in studies by Ledoux et al. (2000), Diaz (2001), Morris (2011) and Papp et al. (2022). However, our recent systematic review has brought to light a limited global consideration of both fauna movement and FSRD in transport planning research (Johnson et al. 2022a). Notably, only around 12 per cent of published research addressing the application of environmental policies in transport projects originated from outside the European Union (see Johnson et al. 2022a). This poses a significant challenge, given the highly variable impacts of roads on landscapes, necessitating tailor-made measures for the effective and impactful implementation of FSRD (Iuell 2003; van der Ree, Smith, and Grilo 2015).

Effective policy implementation in this domain hinges on a robust regulatory framework as emphasised by practices in some European Union member states (Damarad and Bekker 2003; Jones and Pickvance 2013; Wilson, Marsh, and Winter 2007). Although analogous policies have been introduced to a more limited extent by transport infrastructure agencies in Australia (Veith et al. 2015; TMR 2000, 2010; VicRoads 2012), Australia’s regulatory approach to the management of transport infrastructure environmental outcomes is frequently criticised as inadequate (Byrne, Snipe, and Dodson 2014; Macintosh et al. 2018; Rieder 2011; Tridgell 2013). To gauge the extent to which FSRD measures have been considered in Australian transport planning, still in its early stages of adoption, we conducted a systematic literature review using frameworks presented in Pickering and Byrne (2014) and De Vos and El-Geneidy (2022). The focus of the review is on Australia, guided by the question: To what degree are FSRD measures acknowledged and considered in transport planning, as evidenced by the peer-reviewed literature? Due to a lack of information in this area, this review does not consider or explore the outcomes of applying policy directives.

2. Background

The application of the ecologically sustainable development principle in Australia is marked by a lack of clarity and guidance for practitioners in their decision-making processes (England 2005; England 2006a, 2006b; Meurling 2005; Summerville, Adkins, and Kendall 2008). Instead, there is a strong emphasis on regulating ecologically sustainable development through community behaviour and democratic principles such as community rights and responsibilities (Summerville, Adkins, and Kendall 2008). This approach has led to the adoption of passive environmental policies, introducing ambiguity in their interpretation and providing significant discretion in policy options considered during the decision-making process (England 2015, 2016; Fisher 2001b). Decision makers in numerous Australian states and territories are only obligated to ‘have regard to’ or ‘consider’ environmental policies in environmental impact assessment (England 2010; Fisher 2001a; Ives et al. 2010; McGrath 2014). This complexity is further compounded by the limited definition of significant impact and likelihood of significant impact (Fisher 2000; Macintosh 2004; Stein 2000; Williams and Williams 2016). Consequently, when implementing environmental management programmes, decision makers have often prioritised procedural correctness over tailoring approaches to ensure the intended outcomes are achieved (Clement, Moore, and Lockwood 2015; Fisher 2005; Wright 2001).

In Australia, political and economic interests significantly influence infrastructure and transportation provision, often prioritising economic development over environmental sustainability and management (Austin 2000; Caulfield 1993; Curran 2015; Hu 2015). This tendency is evident in the implementation of various biodiversity management plans and initiatives such as the Back on Track species prioritisation framework, the Tasmanian Midlands Water Strategy and the Plan of Management for Kosciuszko National Park, which emphasises cost-effective and orderly implementation without undermining state/territory rights or ownership (Clement, Moore, and Lockwood 2015; Kim et al. 2016). This is reflective of a broader approach by the Australian Government to regulate environmental management and planning through economic instruments, exemplified by the ‘one-stop-shop’ policy aimed at achieving faster, short-term economic gains and administrative efficiency (Brown and Nitz 2000; England 2010; Jaireth and Figg 2014; Moon 1998; Young and Gray 2000).

Despite the intended benefits, these initiatives have adversely impacted the transparency, accountability and quality of the environmental impact assessment process, resulting in delays in project evaluations and limitations on applications (England 2010). Moreover, the mitigation hierarchy – an essential tool in environmental impact assessment aimed at minimising environmental damage through a sequence of avoidance, mitigation and offsetting – has encountered challenges due to the limited capacity of decision makers to accurately assess environmental significance in infrastructure projects. This challenge is further exacerbated by the duplication of environmental impact assessment provisions across different legislations and government levels (England 2010; Marsden and Ashe 2006; Williams and Williams 2016).

The need for a comprehensive review of FSRD policies is evident given the expansive Australian road transport network, which covers approximately 880,000 km (with ∼427,000 km paved), and the substantial annual investments from all levels of government, totalling AUD 36 billion (BITRE 2020; WorldData 2024). This review will provide valuable insights into the acknowledgement and consideration of road ecology principles and FSRD measures in transport planning, which have played a crucial role in improving transportation infrastructure worldwide. Furthermore, this review will pave the way for future research and inform local – and state-level government planning priorities, policies and legislation.

3. Methods

The present study adopted the Pickering and Byrne model (2014) for systematic quantitative literature review, which was modified to align with the PRISMA-P guideline (Moher et al. 2009) and the recommendations of De Vos and El-Geneidy (2022). The latter provides a valuable approach to crafting a review that offers meaningful contributions to the transportation field. Specifically, the framework underscores the importance of demonstrating ‘added value’ by either constructing a conceptual model, pinpointing avenues for future research or examining policy insights and implications. For this study, the focus will be on the latter two aspects.

A literature search, using 143 keyword searches, was conducted across eight journal databases to identify peer-reviewed articles related to environmental management and planning (see supplementary material). This search focused on the implementation and operation of key environmental legislation and policies without necessarily concentrating on the on-the-ground implementation of FSRD. The search was limited to the period after the Earth Summit (1992–2021) when legally binding goals for sustainable development came into existence. The search only included peer-reviewed literature to ensure scientific rigor, and grey literature such as reports, statutes and books were intentionally excluded under the assumption that they were indirectly captured and expanded upon in scientific texts. This methodology is consistent with that used by Johnson et al. (2022b). Following the removal of duplicate records, the articles were classified into two types, namely Type A and Type B papers, based on their content. Type A papers were concerned with environmental policy in infrastructure planning generally, while Type B papers examined environmental policies in transport infrastructure planning (Figure 1).

Figure 1. Prisma-P flow-chart displaying the search process and results of this SQLR.

4. Results

A substantial number of individual search attempts (143) yielded 2,400 peer-reviewed articles. A further 91 articles were obtained by other means, such as contributions of peers and searches of article reference lists. Once all duplicates and peripheral (i.e. non-relevant) articles were removed, only 57 articles remained for quantitative analysis. Following reclassification, 45 Type A papers and 12 Type B papers were identified.

The combined dataset of Type A and B papers displayed a significant geographic bias towards certain regions within Australia. Specifically, Queensland was the focus of approximately 36 per cent of all studies (n = 21), while Victoria (n = 4) and other Australian states/territories (n = 5) received relatively little attention. Moreover, about 32 per cent of the articles analysed examined policies at the national (Australian) level.

Around 75 per cent of papers (Type A and B) employed statutory analysis and/or policy operation as their methodological approach, with a majority focusing on broader environmental legislation and/or policy, particularly the Environment Protection and Biodiversity Conservation Act 1999. Only one article in the reviewed literature explored the content of Australian transport policies and used interviews/surveys of practitioners in its methodological approach. None of the reviewed articles incorporated case studies (i.e. specific real-world applications).

The way in which Type-B papers referenced environmental concerns sheds light on practitioners’ understanding of environmental concepts. The most frequently mentioned environmental concerns were broad and non-specific, including the environment (n = 6), biodiversity (n = 5) and pollution/contamination (n = 5). Only one paper acknowledged fauna movement, and none of the reviewed Type-B papers recognised habitat quality, habitat fragmentation or wildlife-vehicle collisions.

In transport research, resistance towards addressing environmental concerns in policy was found to be primarily due to various factors. Policy misinterpretation (i.e. incorrect understanding and/or application of policy) was cited in seven instances, while conflicted knowledge and political interests (i.e. individual, sector and/or political motivations that run counter to FSRD) were identified as factors in six and five cases, respectively. Regulatory power was also a significant factor, with statutory recognition cited in six instances and statutory confinement (i.e. the extent to which policies may be applicable) in four. Other factors included procedural focus, which was identified in four cases, and poor assessment/monitoring, which was cited in four instances.

5. Discussion

The main finding of this study was that FSRD has not been widely acknowledged in the body of peer-reviewed literature (i.e. published research) focused on Australia. This is concerning because road ecology, which encompasses wildlife biology, engineering and natural areas management, is crucial for sustainable transportation planning. FSRD provides a framework for ecological planning, engineering and mitigation in road transport projects (van der Ree, Smith, and Grilo 2015). In regions like the EU, acknowledging the environmental impacts of roads, particularly on wildlife, in peer-reviewed literature has significantly improved their consideration in transport planning (Damarad and Bekker 2003; Iuell 2003; Johnson et al. 2022b).

Australia’s extensive road network, which interacts with many sensitive landscapes, has the potential to make significant positive contributions to public greenspace and the conservation of biodiversity (Chang, Bertola, and Hoskin 2023; Hamer, Harrison, and Stokeld 2016; Marshall, Grose, and Williams 2019; Munro, Williamson, and Fuller 2018). However, most research on this topic has been from an ecological perspective (Hall et al. 2018; Hawkins, Ritrovato, and Swaddle 2020; Johnson, Evans, and Jones 2017; Goldingay et al. 2018), with few studies critically examining environmental policies within transport departments and institutions.

A poor understanding and recognition of road impacts in legal documents and policy guidelines can leave transport planners ill-equipped to address ecologically sensitive areas, engage stakeholders, secure funding and implement effective mitigation strategies (Papp et al. 2022). The only known critique of transport policies in the Australian transport sector, which also examined environmental aspects, was conducted by Bray, Taylor, and Scrafton (2011), in which 43 urban transport strategies, published between 1965 and 2010, were reviewed. Several key issues were highlighted, including:

1. Similar policies were observed across states and territories, but there was little evidence of critical evaluation of these policies.

2. Recent strategies tended to feature ‘soft’ and ‘aspirational’ policies rather than evidence-based, demand-driven policies prominent in earlier strategies.

3. Environmental consequences of transport infrastructure were addressed only in more recent strategies, focusing mainly on greenhouse gas emissions.

These observations align with the present study’s results, where broader environmental concerns dominated the literature.

6. The legislative framework for fauna-sensitive road design in Australia

The implementation of FSRD measures in national road transport infrastructure projects is limited by the lack of legislative support in current landscape management policies. Few projects meet the criteria for Commonwealth assessment, making national-level implementation of FSRD unlikely (Field, Burns, and Dale 2012; Kennedy et al. 2001; Macintosh 2004). When a road project does qualify for assessment, there is limited scope for considering FSRD measures due to the weak and ineffective mandate for environmental impact assessment in the Environment Protection and Biodiversity Conservation Act 1999 (Commins 1993; Lindsay and Trezise 2016; Tridgell 2013).

The Environment Protection and Biodiversity Conservation Act 1999 allows the Commonwealth to consider impacts on threatened species and ecological communities within the project area (Chapple 2001; Clement, Moore, and Lockwood 2015; Godden and Peel 2007; Macintosh 2004). However, the Act’s definitions of significant impact and the likelihood of significant impact are poorly defined, complicating the assessment of a project’s overall impact (England 1999; Hardman 2003; McGrath 2004; Williams and Williams 2016). Additionally, the Act does not account for cumulative impacts or suitable alternatives for development, which are better addressed through strategic environmental assessment (Hawke 2009; Marsden 2013; Samuel 2020). In Australia, impacts are typically assessed at the project level, with strategic environmental assessment being voluntary and limited to Matters of National Environmental Significance and Matters of State Environmental Significance at the federal level (Kabir, Momtaz, and Morgan 2020; Macintosh 2004; Marsden and Ashe 2006). This contrasts with FSRD, which emphasises the need to consider species within a broader landscape context (van der Ree, Smith, and Grilo 2015), unlike the project-specific focus currently adopted in environmental impact assessment (Hawke 2009; Samuel 2020).

Additionally, the effective implementation of environmental impact assessment relies on access to accurate species and ecosystem information by project planners and assessment managers (Fraser et al. 2019; Simmonds et al. 2019). However, recovery, threat abatement and conservation plans suffer from several inadequacies: (1) a significant time gap between species listing and plan publication, (2) inconsistent measures for mitigating identified threats and (3) ineffective criteria for evaluating performance (Lindsay and Trezise 2016; Ortega-Argueta, Baxter, and Hockings 2011). These plans offer only guidance and are enforceable only if incorporated into approval conditions (Lindsay and Trezise 2016). Two statutory reviews of the Environment Protection and Biodiversity Conservation Act 1999, Hawke (2009) and Samuel (2020), recommended addressing these shortcomings, but implementation has yet to occur. Consequently, the Commonwealth’s capacity to mitigate project impacts on threatened species and ecological communities remains limited (Simmonds et al. 2019).

State and territory governments, primarily responsible for land-use and landscape management, often lack the capacity to consider FSRD policy measures (Clement, Moore, and Lockwood 2015; Grant and Papadakis 2004; Gurran, Gilbert, and Phibbs 2015; Sollberger 2006). Similar to the Commonwealth, inconsistencies in conservation and land-use management legislation are prevalent (Clement, Moore, and Lockwood 2015; Simmonds et al. 2019), with many states prioritising the economic benefits of infrastructure projects (Boge 2017; England 2015; Gleeson and Low 2000).

Queensland, which featured prominently in the present study, exemplifies this issue with its history of turbulent land-use management and emphasis on microeconomic reform since the early 1990s (England 2010; England and McInerney 2017; Homel 1999; Williams and Williams 2016). The introduction of the Planning Act 2016 further shifted procedural matters to separate regulations and non-mandatory best practice guidelines (England 2015; 2016). These changes gave decision makers discretionary powers to choose which non-mandatory guidelines, like environmental impact assessment, to consider in infrastructure assessments (England 2015, 2016; Field, Burns, and Dale 2012; Williams and Williams 2016). FSRD in Queensland also exists as a non-mandatory administrative guideline, similar to environmental impact assessment (TMR 2010).

Victoria has a non-mandatory FSRD guideline (VicRoads 2012) similar to Queensland’s, likely due to knowledge transfer between the two states, akin to the spread of transport strategies described by Bray, Taylor, and Scrafton (2011). However, due to limited published literature on transport and environmental policy, it is unclear how the Victorian FSRD guideline is applied in infrastructure projects, as noted in this study.

7. Implications and future directions

This systematic review found that, although FSRD guidelines have been in place in Australia, at the state level, for over a decade, road ecology and FSRD are not widely acknowledged or considered in road transport infrastructure planning. Two recent studies, Johnson et al. (2022b) and Papp et al. (2022), provided useful insights into the current and emerging practices of FSRD on a broader scale. This study offers a more nuanced approach to FSRD in Australia, a large and economically advanced country with few publicly available FSRD policies and a history of substandard landscape management. Indeed, it is the first study of its kind in Australia.

Australia’s FSRD guidelines are largely symbolic and carry little weight in the decision-making process. They exist solely as non-mandatory administrative guidelines, within two states, making them susceptible to exclusion due to the numerous exemptions and discretionary powers granted by statutes. Even when FSRD guidelines are considered by decision makers, achieving meaningful conservation outcomes is challenging as environmental planning in Australia is deficient both in language and content, characterised by flawed planning, monitoring and management practices. Additionally, the administration of Australia’s sustainability principles through passive and ambiguous regulation has allowed economic interests and attitudes to proliferate and become entrenched. For example, ecologically sustainable development is a principle that many Australian governments strive for but have trouble achieving due to the significant discretionary powers afforded to policy- and decision-makers, compounded by limited definition and guidance of key terminologies such as ‘significant impact’ and ‘likelihood of significant impact’.

Developing linear transport infrastructure that meets ecologically sustainable development principles requires dialogue and cooperation between departments. Road ecology plays a crucial role in this process, combining research insights and industry best practices from various disciplines such as wildlife biology and road engineering. By fostering interdisciplinary collaboration, road ecology can help bridge the gap between environmental sustainability and infrastructure development, ensuring that conservation goals are integrated into the planning and implementation of road projects.

The current study acknowledges certain limitations that warrant acknowledgment. Firstly, it is essential to recognise the confined scope of the research, which specifically targeted Australian published literature. While some may view this as a limitation, we contend that it serves as a strength for the study. As discussed earlier, the intricate and diverse nature of the relationship between roads and landscapes makes FSRD implementation challenging, necessitating a foundational understanding of the policy environments in the regions in which they operate. The present review establishes a baseline for the Australian context, introducing new insights that complement broader-scale analyses available in other regions (see Johnson et al. 2022a and Papp et al. 2022). Additionally, we assert that the chosen keyword strings were sufficiently broad to encompass all peer-reviewed literature pertinent to this topic, aligning with the typical approach adopted by road transport planners in Australia.

Secondly, the study did not evaluate the degree to which Australian environmental and FSRD policies have been incorporated into transportation infrastructure policy and planning. Although this was beyond the scope of the review and such information may reside in the grey literature (see Bray, Taylor, and Scrafton 2011), it raises concerns about the level of integration, particularly given the issues with environmental legislation in Australia, especially concerning development referrals and approvals. Additionally, the limited scope of policy learning within and between government institutions, as noted by Bray, Taylor, and Scrafton (2011), may explain why FSRD in Australia currently exists only as non-mandatory best practice guidelines in two states.

Further exploration into the factors facilitating the acceptance and integration of FSRD in Australia is imperative. Employing a mixed-methods approach, which utilises linguistic analytical tools and incorporates follow-up interviews with transport practitioners, can effectively scrutinise FSRD policy. This action-oriented methodology, proven successful in assessing biodiversity conservation policies in Australia (see Clement, Moore, and Lockwood 2015), holds considerable value for transport practitioners. In addition to gauging the knowledge and experience of policy and decision makers regarding FSRD policies, this approach would shed light on:

• The conditions that facilitated the incorporation of FSRD from road ecology concepts and research into the transport sectors of Australian states and territories.

• Areas that could be further developed to enhance the practical implementation of FSRD measures.

Roads divide habitats and impede wildlife movement, but the judicious application of FSRD interventions can mitigate such impacts. Although FSRD implementation is still in its early stages, there is substantial potential for its adoption in the Australian transport sector. Achieving effective institutional change requires supportive policies and practical user experiences, an area where Australia currently lags behind other advanced nations. Nonetheless, valuable lessons can be gleaned from the experiences of other countries in implementing FSRD, providing insights that can contribute to a more successful adoption and implementation of the approach in Australia.

Author contributions

Conceived the systematic quantitative literature review: CJ, TM. Performed the systematic quantitative literature review: CJ. Analysed the data: CJ. Contributed materials/critique/analysis tools: CJ, TM, MB and DJ. Wrote, formatted and edited the paper: CJ, TM, MB, and DJ.

Acknowledgments

Special thanks go to Daryl Evans for their valuable insight and contributions toward data analysis and comments. Thanks also to Dan Pagotto, Alexandra White and Maree Hume for their assistance in reviewing the systematic quantitative literature review database search methodology. I am also grateful to the academic reviewers whose valuable comments helped to improve the quality of this manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).