An Analytical Framework of the Factors Affecting Wildlife–Vehicle Collisions and Barriers to Movement

Round 1

Reviewer 1 Report

I enjoyed reading your review' Here I give you a few  some suggestions  that will hopefully improve the final version.

Line 89:  (and elsewhere) 'matting' should be changed to 'mating'. I think this sentence would be better as follows 'traits, such as reproductive behaviours, such as rutting and mating, migration, dispersal.....'

Lines 151-2: 'Once wildlife ventures on a road, many factors..........of safe exit on the other side.'

Line 153: 'time of day', driver-related

Line 168: replace 'adapted' with 'habituated'

Lines 190-1: I think some factors on this list require a little more explanation, such as 'various road uses'. Delete rutting and mating and keep 'reproductive and breeding behaviours, seasonal migrations, post-breeding dispersal, movements to hibernation locations'

Table 1: change 'matting' to 'mating'

Line 199: In the section on birds you should include something on increased vulnerability of birds during the nesting season. When incubating birds nesting in low roadside vegetation (e.g. hedgerows) flush/depart from nests they often fly low over the open road and are very vulnerable to VWCs.

Later in this paragraph (around line 212) it might be worth mentioning that in northern latitudes, just after dawn, birds often sit on tarmac roads which are warmer relative to dew-laden roadside vegetation

Line 250: replace 'stun' with 'dazzle'

Line 253: rejig this sentence to read 'Roadside vegetation can be an attractive habitat to a wide range of wildlife, or act as a corridor for movement.'

Line 344: again, this sentence may read better as 'there remain more undocumented variables, and interactions between known variables, yet to be revealed.'

Paragraph starting line 350: Maybe insert a few sentences here on the 'state of play' with respect to mitigation options using wildlife overpasses (green bridges) or underpasses

Line 357: replace 'deep' with 'significant'

 

 

 

The English is acceptible and understandable

Author Response

We appreciate very much the reviewers’ valuable comments and suggestions for our paper. These suggestions have crucial guiding significance for the improvement of the paper and the progress of our personal academic research level, and we learn a lot from them. We have carefully studied the comments and suggestions, and made corresponding revisions after careful consideration.

 

Reviewer 1

I enjoyed reading your review' Here I give you a few some suggestions that will hopefully improve the final version.

 

Line 89: (and elsewhere) 'matting' should be changed to 'mating'. I think this sentence would be better as follows 'traits, such as reproductive behaviours, such as rutting and mating, migration, dispersal.....'

RESP: Revised according to the suggestion.

 

Lines 151-2: 'Once wildlife ventures on a road, many factors..........of safe exit on the other side.'

RESP: Revised according to the suggestion.

 

Line 153: 'time of day', driver-related

RESP: Revised according to the suggestion.

 

Line 168: replace 'adapted' with 'habituated'

RESP: Revised according to the suggestion.

 

Lines 190-1: I think some factors on this list require a little more explanation, such as 'various road uses'. Delete rutting and mating and keep 'reproductive and breeding behaviours, seasonal migrations, post-breeding dispersal, movements to hibernation locations'

Table 1: change 'matting' to 'mating'

RESP: Revised according to the suggestion.

 

Line 199: In the section on birds you should include something on increased vulnerability of birds during the nesting season. When incubating birds nesting in low roadside vegetation (e.g. hedgerows) flush/depart from nests they often fly low over the open road and are very vulnerable to VWCs.

Later in this paragraph (around line 212) it might be worth mentioning that in northern latitudes, just after dawn, birds often sit on tarmac roads which are warmer relative to dew-laden roadside vegetation

RESP: Added according to the suggestion. But the first case is placed at the below paragraph concerning ‘roadside vegetation’.

 

Line 250: replace 'stun' with 'dazzle'

RESP: Revised according to the suggestion.

 

Line 253: rejig this sentence to read 'Roadside vegetation can be an attractive habitat to a wide range of wildlife, or act as a corridor for movement.'

RESP: Revised according to the suggestion.

 

Line 344: again, this sentence may read better as 'there remain more undocumented variables, and interactions between known variables, yet to be revealed.'

RESP: Revised according to the suggestion.

 

Paragraph starting line 350: Maybe insert a few sentences here on the 'state of play' with respect to mitigation options using wildlife overpasses (green bridges) or underpasses

RESP: Revised according to the suggestion. I have added several sentences to describe this.

 

Line 357: replace 'deep' with 'significant'

RESP: Revised according to the suggestion.

Reviewer 2 Report

This study summarises the comprehensive factors affecting wildlife roadkill as well as the main transmission mechanisms, which makes a useful contribution to the literature. I enjoyed reading this manuscript, however, improvement and adequate elaboration on the points below is expected to clear the way for acceptance.

 

1. Lines 45-49 “While numerous factors have been discussed, … as well as the underlying transmission mechanisms.” – As one would argue that the factors affecting WVCs may vary by geographical location and circumstances, and can be species-specific, I think the authors need to add a few lines to explain the significance of having a complete framework comprising different factors of WVCs – i.e. why it is important to have such a complete list (instead of only to pick up a set of factors of interest) and what insight could this provide?

 

2. Lines 48-49 “There remains a lack of a relatively complete framework comprising the large-scale factors of WVCs” – I’m not sure if this study sought to establish a framework for all possible factors that may affect the occurrence of wildlife roadkill, or only for “large-scale” factors? I suppose “large-scale” factors referred to the landscape and environmental characteristics in contrast to the individual-related factors (e.g. driver’s visibility, attention, species’ mobility, etc.) and therefore suggest re-phrase here.

 

3. Lines 242-243 “Raised roads or roadsides with high embankments decrease the risk of WVCs of many species, but this may not be the case for birds” – would the transmission mechanisms vary by species? (More discussions on this would be welcome.)

 

4. Lines 350-353 “Second, the impacts of WVCs on wildlife populations worldwide have not been extensively studies; … it is suggested that research on birds, amphibians, reptiles, and invertebrates be initiated in the near future.” – Despite that I agree with the authors on this point, I still don’t think this is quite relevant to any of the main objectives of this study.

 

5. Lines 354-359 “Finally, WVC databases are vital to determining the impacts of road networks and transportation on wildlife, and database construction can arouse the consciousness of wildlife preservation by public science.” – I wonder whether the authors have identified any current data gaps related to key environmental factors affecting wildlife roadkill that must be addressed?

Author Response

Reviewer 2

Comments and Suggestions for Authors

This study summarises the comprehensive factors affecting wildlife roadkill as well as the main transmission mechanisms, which makes a useful contribution to the literature. I enjoyed reading this manuscript, however, improvement and adequate elaboration on the points below is expected to clear the way for acceptance.

 

1. Lines 45-49 “While numerous factors have been discussed, … as well as the underlying transmission mechanisms.” – As one would argue that the factors affecting WVCs may vary by geographical location and circumstances, and can be species-specific, I think the authors need to add a few lines to explain the significance of having a complete framework comprising different factors of WVCs – i.e. why it is important to have such a complete list (instead of only to pick up a set of factors of interest) and what insight could this provide?

RESP: Presenting a relatively complete framework comprising a large number of factors affecting WVCs can help to guide empirical studies to consider various possible related factors more comprehensively in specific circumstances, thus improving the general principles of empirical models, compared to only picking up a set of factors of interest.

Added according to the suggestion.

 

2. Lines 48-49 “There remains a lack of a relatively complete framework comprising the large-scale factors of WVCs” – I’m not sure if this study sought to establish a framework for all possible factors that may affect the occurrence of wildlife roadkill, or only for “large-scale” factors? I suppose “large-scale” factors referred to the landscape and environmental characteristics in contrast to the individual-related factors (e.g. driver’s visibility, attention, species’ mobility, etc.) and therefore suggest re-phrase here.

RESP: We try to establish a framework for all possible factors related to WVCs.

Revised according to the suggestion.

 

3. Lines 242-243 “Raised roads or roadsides with high embankments decrease the risk of WVCs of many species, but this may not be the case for birds” – would the transmission mechanisms vary by species? (More discussions on this would be welcome.)

RESP: Because for most species, raised roads increase the difficulty of road entering. But for birds, raised roads may actually reduce the flight height of birds relative to roads. 

 

4. Lines 350-353 “Second, the impacts of WVCs on wildlife populations worldwide have not been extensively studies; … it is suggested that research on birds, amphibians, reptiles, and invertebrates be initiated in the near future.” – Despite that I agree with the authors on this point, I still don’t think this is quite relevant to any of the main objectives of this study.

RESP: OK, we deleted this part to avoid confusion.

 

5. Lines 354-359 “Finally, WVC databases are vital to determining the impacts of road networks and transportation on wildlife, and database construction can arouse the consciousness of wildlife preservation by public science.” – I wonder whether the authors have identified any current data gaps related to key environmental factors affecting wildlife roadkill that must be addressed?

RESP: OK, we deleted this part to avoid confusion.

Reviewer 3 Report

This paper has the potential to make a useful contribution to the discussion of wildlife vehicle collisions, however, the argument of the paper must be established and developed throughout the paper.  This argument could be about the existing frameworks and how they could be improved.  This line of argument has been hinted about by the author but needs to be made explicit (which frameworks), analysed (what are the strengths and limitations of the frameworks), and evidence provided as to why their framework is better.

System diagrams like those presented in the paper can be powerful ways to visualise the different elements that need to be considered in a framework.  The diagrams provided don't achieve this yet.  Greater clarity might be achieved by using plus and minus signs to indicate where factors are facilitating or hindering road crossing.  However, it needs to be made clear whether the relationships described in the diagrams apply to all species involved in wildlife vehicle collisions or just some species.

It would help your argument significantly if you chose two or three species that could showcase different situations that you then use as case studies to demonstrate how the model contributes to the understanding of wildlife vehicle collisions and/or management of this interaction.  

Revisions must address the comments above and the comments made on the attached document.

Comments for author File: Comments.pdf

There are a few spots where the English could be improved.  Please see the attached document for details.

Author Response

Reviewer 3

This paper has the potential to make a useful contribution to the discussion of wildlife vehicle collisions, however, the argument of the paper must be established and developed throughout the paper.  This argument could be about the existing frameworks and how they could be improved.  This line of argument has been hinted about by the author but needs to be made explicit (which frameworks), analysed (what are the strengths and limitations of the frameworks), and evidence provided as to why their framework is better.

RESP: While numerous factors have been discussed, most empirical studies have considered only a small portion of the factors, and the few relevant review studies have also tended to focus on only some types of factors and the influence direction of each single factor. There remains a lack of a relatively complete framework comprising a wide range of factors of WVCs, as well as the underlying transmission mechanisms. Indeed, the factors influencing WVCs may vary by geographical location and circumstance, and can be species-specific. It remains necessary to present a relatively complete framework comprising a large number of factors affecting WVCs, as well as the transmission mechanisms between some factors. This can help to guide empirical studies to more comprehensively consider various possible related factors in specific circumstances, thus improving the general principles of empirical models as compared to the selection of only a single set of factors of interest.

In this study, a relatively complete framework of factors related to WVCs was integrated. The framework includes a wide range of factors affecting WVCs, the possible influence direction of each factor, potential explanations under different circumstances, and interactions between factors. This framework can be used to make theoretical contributions and provide more perspectives for relevant empirical studies. In addition, although numerous internal and external factors associated with WVCs have been discussed, more undocumented variables and the interactions between known variables have yet to be revealed. This can be remedied by the use of better quantitative models in the future.

Some revisions and additions are made in the section of introduction to clarify the problem statement and research gap more clearly. The contributions and limitations of the study are also added to the section of conclusion.

 

System diagrams like those presented in the paper can be powerful ways to visualise the different elements that need to be considered in a framework.  The diagrams provided don't achieve this yet.  Greater clarity might be achieved by using plus and minus signs to indicate where factors are facilitating or hindering road crossing.  However, it needs to be made clear whether the relationships described in the diagrams apply to all species involved in wildlife vehicle collisions or just some species.

RESP: We have re-drawn all the figures to replace the previous editions. The figures are used to display the relationships between factors, involving a wide range of species.

 

It would help your argument significantly if you chose two or three species that could showcase different situations that you then use as case studies to demonstrate how the model contributes to the understanding of wildlife vehicle collisions and/or management of this interaction.  

RESP: In fact, in our study, special attention was paid to three types of literature, namely, those discussing factors rarely mentioned in previous relevant reviews, those drawing conclusions about the influence direction of some factors that differed from most studies, and those providing representative interpretations for the influence direction of factors.

We have provided some cases of different situations involving certain species. For example, raised roads or roadsides with high embankments decrease the risk of WVCs of many species, but this may not be the case for birds. This is because, for most species, raised roads increase the difficulty of entering the roads; for birds, however, raised roads may actually reduce the bird flight height relative to roads.

 

Revisions must address the comments above and the comments made on the attached document.

    RESP: We have responded to the comments made on the attached document point by point in PDF.

Author Response File: Author Response.pdf

Reviewer 4 Report

Thank you for giving me a chance to review the manuscript entitled “An analytical framework of the factors affecting wildlife-vehicle collisions and barriers to movement”. The paper is well-written and addresses important issues. However, many comments still need to be considered to improve the paper's quality to be ready for publication.

 

-        In the introduction, it is better to add statistics about the number of Road mortality and Wildlife-vehicle collisions in the last few years. In addition, the problem statement and gap are not clear.

 

-        The methods section should describe what was done to answer the research question, describe how it was done, justify the research design, and explain how the results were analysed. Also, the author should write about excluding and inclusion criteria by mentioning the number of papers found and how you reached One hundred and fifty studies in the last stage. All these important steps were missing in the method section.

 

-        I would suggest drawing another suitable figure for figures 1, 2, and 3.

 

 

-        In the scientific paper, authors should avoid using “etc.”. If you still have many examples or factors, you can write it as your references wrote it, otherwise, you don't need to.

 

-        Figure 4 is confusing; please find another way to easily present the effect or relationships between all variables in this study.

 

 

-        In  conclusion, the practical and theoretical contributions of the study are missing. Also, the limitations of the study, please add it. 

Author Response

Reviewer 4

Thank you for giving me a chance to review the manuscript entitled “An analytical framework of the factors affecting wildlife-vehicle collisions and barriers to movement”. The paper is well-written and addresses important issues. However, many comments still need to be considered to improve the paper's quality to be ready for publication.

 

-        In the introduction, it is better to add statistics about the number of Road mortality and Wildlife-vehicle collisions in the last few years. In addition, the problem statement and gap are not clear.

RESP: We have also been trying to present the recent statistics about the number of road-kill, but there may be a lack of specific global data in the last few years. We only found road-kill data on some types of species in some regions in previous literature.  

Some revisions and additions are made to clarify the problem statement and research gap more clearly.

 

-        The methods section should describe what was done to answer the research question, describe how it was done, justify the research design, and explain how the results were analysed. Also, the author should write about excluding and inclusion criteria by mentioning the number of papers found and how you reached One hundred and fifty studies in the last stage. All these important steps were missing in the method section.

RESP: Actually, according to the research topic and objectives, we did not conduct a systematic review. Initially, we had a draft framework based on our research basis. To establish the whole analytical framework, on the one hand, we conducted literature search, and on the other hand, we made literature tracking, especially based on relevant review studies. Then, we incorporated important literature as a foundation to support, refine, and expand the initial framework. Notably, we paid special attention to three types of literature: those discussing factors rarely mentioned in previous relevant reviews, those drawing conclusions about the influence direction of some factors that differed from most studies, and those providing representative interpretations for the influence direction of factors.

Some additions are made into this section.

 

-        I would suggest drawing another suitable figure for figures 1, 2, and 3.

RESP: OK, we have drawn new figures to replace the previous editions.

 

-        In the scientific paper, authors should avoid using “etc.”. If you still have many examples or factors, you can write it as your references wrote it, otherwise, you don't need to.

RESP: Revised according to the suggestion.

 

-        Figure 4 is confusing; please find another way to easily present the effect or relationships between all variables in this study.

RESP: OK, we have drawn a figure to replace the previous edition.

 

-        In conclusion, the practical and theoretical contributions of the study are missing. Also, the limitations of the study, please add it. 

RESP: Added according to the suggestion.

 

Round 2

Reviewer 3 Report

Version two is not a major revision.  The concerns raised about the argument and the need for clear frameworks has not been addressed.  What the authors identify as frameworks are inverse perspectives of the same thing; in other words a false dichotomy.  

 

Guidance was provided in the first lot of reviewer comments to assist with English expression, yet the authors have not heeded the suggestions.  

Author Response

We have made additions to clarify the existing research gap, and demonstrate the significance and contributions of our framework more clearly. In addition, we responsed to the comments in previous PDF point by point. We believe that many of the reviewer's understandings and comments on our study may not be accurate.

Author Response File: Author Response.pdf

Reviewer 4 Report

I have seen a good job, the authors took my comments seriously. however, I still have concerns about the writing of the method section.

As the authors replied they were going through the literature review paper, not a systematic paper. So the method of the literature review paper should include, for example, purpose and research question, and search Strategy. In addition, the inclusion and exclusion criteria in a literature review paper may be flexible and broader. The goal is to include studies that contribute to the understanding of the topic, even if they have some limitations or variations.

 

Author Response

Revised according to the suggestion.

Author Response File: Author Response.pdf

Round 3

Reviewer 3 Report

I have made multiple efforts to try and improve your paper, yet you chose to ignore these suggestions.  I am therefore rejecting the paper.

There were errors for which I offered suggestions and yet the authors only provided responses in the comments rather than improving the manuscript text, unless directed to make changes to the manuscript.