Predicting the Spatial Distribution of the Mangshan Pit Viper (Protobothrops mangshanensis) under Climate Change Scenarios Using MaxEnt Modeling

Round 1

Reviewer 1 Report

Protobothrops mangshanensis is listed as IUCN Endangered (IUCN 3.1) and CITES Appendix II (CITES). It is endemic to Hunan and Guangdong provinces in China. Breeding has been successful in Germany, China and the United States, including a conservation program at the San Diego Zoo. The total number is estimated to be around 300–500 individuals, which is a critical level. For the conservation of the species, microclimatic conditions are the determining important factors. At the same time, with global climate change, microclimatic features cannot always reduce the impact, which leads to a reduction in suitable habitats. And factors such as removal for trade, including for food purposes, and deforestation of habitats increase the negative impact on populations.

The research is current.

Notes:

1) Fig. 1 It is necessary to improve the design, increase the size of photographs of typical habitats of Protobothrops mangshanensis. I note that in Fig. 4 repeats the study area on a different scale.

2) Line 383 Conclusions must be formulated more specifically, indicating:

- the main factors influencing the abundance of the species;

- mark areas with the most threatened climate characteristics;

- determine the necessary protection measures and restoration of numbers.

3) The authors note the possibility of artificial breeding, but without references. Additional information needs to be added. Another aspect of conservation appears to be artificial structures - shelters and food support, including maintaining the number of amphibians.

4) Text formatting, line 534 “37. Román"

Author Response

Dear Reviewer,

First and foremost, I would like to extend my deepest gratitude for your thorough review and insightful feedback on our manuscript. Your comments have provided us with valuable guidance on how to further improve our work.

In response to your notes:

1)Thank you for your suggestion regarding Figure 1. We agree that improving the design and increasing the size of photographs of typical habitats of Protobothrops mangshanensis would enhance the readability and understanding of the figure. We will make the necessary adjustments to improve the figure's design and clarity. Additionally, we acknowledge the repetition of the study area in Figure 4 on a different scale and will consider revising it to avoid redundancy.

2)Thank you for pointing out the need for more specific conclusions. We will revise the conclusions section to clearly indicate the main factors influencing the abundance of the species, mark areas with the most threatened climate characteristics, and determine the necessary protection measures and restoration of numbers in lines 539~552.

3)Thank you for highlighting the lack of references regarding artificial breeding. We will add relevant references (the reference 8) to support our claim and provide additional information on artificial breeding practices. Furthermore, we appreciate your insight into conservation measures such as artificial structures, shelters, and food support. We will explore these aspects further and incorporate them into our discussion on conservation strategies in lines 591~598.

4)Thank you for bringing up the text formatting issue at line 534. We apologize for the mistake and will correct the formatting to ensure consistency and readability.

We appreciate your valuable feedback and will incorporate your suggestions into our manuscript to improve its clarity, accuracy, and overall quality.

Author Response File: Author Response.pdf

Reviewer 2 Report

As I mentioned earlier, this is totally out of my area of expertise so I cannot comment on most of the text.  It appears sound but that is all I can say.  I suggest adding a bit more about the snake on page 2.  After Squamata and between Viperidae should come Serpentes.  I would also include that it occurs from 700–1300 m in elevation (I am a bit surprised that elevation was not a consideration and did not enter the study).  Also, the snake is large and grows to a maximum length of 2030 mm.  Lastly, I would suggest a color photo be included as it is a beautiful snake and uniquely patterned for life in the forest.  I am sure that Nikolai Orlov would contribute one for the paper.

Author Response

Dear Reviewer,

Thank you very much for your valuable feedback on our manuscript. We appreciate your suggestions and comments, which have helped us improve the quality of our paper.

We have carefully considered your recommendation to include more information about the snake species on page 2. Accordingly, we have added the taxonomic classification "Serpentes" after "Squamata" and before "Viperidae" to clarify its phylogenetic position.

Regarding the elevation range of the snake, we completely agree that this is an important aspect to include. In fact, during our initial factor selection process, we did consider elevation data. However, upon conducting a correlation analysis, we found a high correlation between elevation and certain temperature factors (bio 5, bio 8, bio 10, etc.). To prevent overfitting in our Maxent model and ensure a more parsimonious analysis, we opted to retain the more intuitive and ecologically significant temperature factors. And we add the factor in Materials and Methods for the line 183

Furthermore, we are grateful for your idea to include a color photo of the snake. We agree that it is a striking species with a unique pattern adapted to forest life. In response, we have added a color photograph of the snake in its natural habitat to enhance the reader's understanding and appreciation of this beautiful species.

We believe these changes have strengthened our manuscript and made it more comprehensive. Thank you once again for your invaluable input.

Best regards

Author Response File: Author Response.pdf

Reviewer 3 Report

The manuscript provides several MaxEnt models of the current distribution of a critically endangered snake species and the future tendences in the potential habitat range for over 50 years from now. The study is of high interrest for the readers and possess a good potential to contribute to the field. The methods are properly selelcted and well described. As far as I can judge, the MaxEnt procedures are valid and the end products are of good quality. The modeling of habitat distribution may be widelly speculative, because the species may simply not migrate to the newly predicted habitats, however this is the point of view of the authors and such scenario can not be excluded. I completelly agree with tha authors that the GIS database has to remain close, because only in several yers over 30 specimens (out of about 450 animals in the wild) were illigaly obtained in the past. The study is within the scope of the journal and the manuscript can be accepted for publication after major revision.

In the current form of the paper the text is rather poorly edited. There are so many editorial flauts that I will not list them all. Starting with the title and everywhere in the text all latin names have to be in italic. The affiliations are not uniform, there are a lot of typos and bad citations where the name of the author is provided, but not the year  of publication (Lines 330, 341) and some citattions are provided with the abreviated first name of the author besides the family name (not according to the instruction of the journal).  

A weak point of the manuscript is that it deals with modeling of the species habitat based only on data concerning physical factors. I completelly undertand the idea that the habitat shift concerning the climat change is the main scope of the investigation and I can accept this, however the authors have to support their decisions by providing much more biological background. There are some data concerning the general biology and the ecology of the snake species and they have to be described in detail (individual home range, diet, ontogenetical shift, habitat preferences, migration, behavior). The species is poorly detectable (in several years only 8 animals were found in a previous study), however some data exist and these data have to be introduced and discussed. 

The authors provide no data from field surveys, but show original pictures from the natural habitat of the snake and one specimen. This topic has to be explained in detail in the Material and Method section. How was the suitable habitat recognised and documented? Figure 1 is based on published and unpublished data, but how were these unpublished data obtained? Including Figure 1, all other figures have to be described in more details.

Concerning the quality of the figures, I have some struggle. I have no idea how the figures will be uploaded in the end version of the manuscript, but in the .pdf form a lot of them are practically useless. The journal is publishing the figures as separate files, which can be opened and enlarged, however even in this scenario details will not be recognised from the tiny pictures. I can not judge concerning the quality of the images only from the .pdf and the authors have to be sure that the images possess enough resolution. The maps on Figures 5, 6 and 7 are not formated in a reader-friendly way. I will propose the empty northern part to be removed and the actually interesting sections to be exposed in detail. 

Figure 8 is rather confusing and I think that the authors have to chose a more logical design.

The discussion is too brief and in my oppinian it should include a paragraph concerning the potential of the species to migrate and the probability of leaving its current habitat and to inhabit the modeled habita in the future (from biological point of view). The conclusion is too large and confusing. In my oppinion the conclusion must be based on the local ecological legislation - what is possible to be increased in the protection according to the law and the financial instruments. All other demands are rather plakative and lack concretics (where will the funding come from, who will patrool, who will provide field work and how intensive).

The text concerning the appendix 1 and 2 has to be removed and the Literature list has to be edited according to the instructions to authors - in the current form there are to many unactive links, typos and lacking of DOI.

The manuscript has to be rewritten and thoroughly edited by a native speaker.

Author Response

Dear Reviewer,

Thank you for your valuable feedback on our manuscript. We appreciate your thoughtful comments and suggestions. In response to your inquiries, we provide detailed clarifications below.

In the current form of the paper the text is rather poorly edited. There are so many editorial flauts that I will not list them all. Starting with the title and everywhere in the text all latin names have to be in italic. The affiliations are not uniform, there are a lot of typos and bad citations where the name of the author is provided, but not the year of publication (Lines 330, 341) and some citattions are provided with the abreviated first name of the author besides the family name (not according to the instruction of the journal).

Response: Thank you for your feedback on the editorial quality of our paper. We deeply appreciate your attention to detail and the valuable insights you have provided. Regarding the italicization of Latin names, we have overlooked this important formatting aspect. We will ensure that all Latin names in the revised version are properly italicized, starting from the title and throughout the entire text. Moreover, you have pointed out inconsistencies in the affiliations, which we will address by standardizing them in the revised manuscript. We apologize for the typos and bad citations you have mentioned. We will carefully review the entire text and correct all typographical errors, as well as ensure that citations are properly formatted, including both the author's name and the year of publication. We will also eliminate any citations that use abbreviated first names and adhere strictly to the journal's instructions for citation format. We take your comments seriously and will make every effort to improve the quality of our paper. We are committed to submitting a revised version that addresses all the issues you have raised and meets the journal's standards for publication.

Thank you again for your helpful feedback. We look forward to improving our paper and submitting it for further consideration.

A weak point of the manuscript is that it deals with modeling of the species habitat based only on data concerning physical factors. I completelly undertand the idea that the habitat shift concerning the climat change is the main scope of the investigation and I can accept this, however the authors have to support their decisions by providing much more biological background. There are some data concerning the general biology and the ecology of the snake species and they have to be described in detail (individual home range, diet, ontogenetical shift, habitat preferences, migration, behavior). The species is poorly detectable (in several years only 8 animals were found in a previous study), however some data exist and these data have to be introduced and discussed.

Response: I would like to express my deepest gratitude for your careful review and valuable feedback on our manuscript. Your comments have provided us with crucial insights for further improving our work.

Firstly, Firstly, I fully understand your concern regarding the limited focus on biological factors in our modeling of species habitats. Your suggestion to strengthen the biological background in support of our decisions is indeed pertinent. In the revised version, we will certainly delve deeper into the specific biology and ecology of the snake species, in Introduction, particularly in lines lines 94~120.

Moreover, you mentioned the challenge of detecting this species, highlighting the in several years only 8 animals were found in a previous study. However, please note that the eight recorded in GBIF or other database do not represent the total number of sites where the species has been observed. Since 2013, our team has been involved in the Endangered Wildlife Protection project funded by the Hunan Forestry Bureau of China (Project Numbers: HNYB-2013001 to HNYB-2023001). Using the methods described in Zhang, B, Wu, B, Yang, D, et al. (2020), we have conducted monthly surveys from April to November each year, identifying individuals based on their unique head patterns. Over the past decade, we have documented more than 100 individual snakes. As of 2016, Zhang B mentioned in his article (reference 19) that we had recorded more than 60 individuals from 2012 to 2016. Between March and October 2023, the number of Mangshan pit vipers discovered exceeded 15 individuals, making it the year with the highest number of discoveries for this species. However, the discovery loci of some individuals (especially juveniles) are completely identical to those of several adult females. Therefore, the loci information of these individuals is excluded from the data scope of this paper. As a result, we ultimately only included 83 loci, far fewer than the number of different individuals we found.

It is important to clarify that, due to the strict requirements of the project, the detailed data on discovery times, locations, and individual counts have not been publicly released to prevent illegal poaching activities. Nevertheless, we will strive to provide additional relevant information in the revised manuscript, while adhering to the confidentiality regulations.

Additionally, the data from 2008 to 2013 was sourced from the Administration Bureau of Hunan Mangshan National Nature Reserve and is primarily based on the discovery of nests of this species. This information has been invaluable in understanding the species' habitat preferences and ecological niches.

We recognize the significance of providing comprehensive data to support our research conclusions. Therefore, in the revised manuscript, we will enhance the biological background while adhering to the confidentiality requirements of the project.

Thank you again for your insightful comments. We look forward to submitting a revised manuscript that addresses your concerns and presents a more comprehensive study.

The authors provide no data from field surveys, but show original pictures from the natural habitat of the snake and one specimen. This topic has to be explained in detail in the Material and Method section. How was the suitable habitat recognised and documented? Figure 1 is based on published and unpublished data, but how were these unpublished data obtained? Including Figure 1, all other figures have to be described in more details.

Response: We appreciate your comments regarding the need for more detailed information on our field surveys and data collection methods. In the revised version of our manuscript, we will provide a comprehensive description of our material and methods section to address these concerns. Firstly, we will clarify that our field surveys were conducted using transect surveys, as you have mentioned. We will specify the time frame of our surveys, which was from 2012 to 2023, and provide details on the number of transects we randomly arranged in the distribution area of P. mangshanensis. We will also indicate the average length of each transect and explain how we handled inaccessible areas. However, due to the conservation requirements of the Ministry of Forestry of China and the Hunan Provincial Forestry Bureau for this species, we cannot disclose detailed information such as the specific discovery time, longitude and latitude of discovery, detailed location names of discovery sites, and the gender of the species. Therefore, these data sources are unpublished. For all other figures, we will provide a thorough description of their content, the methods used to generate them, and their significance in supporting our findings in lines 147~166.

Thank you again for your valuable feedback. We will ensure that the revised version of our manuscript addresses all your concerns and meets the journal's standards for publication.

Concerning the quality of the figures, I have some struggle. I have no idea how the figures will be uploaded in the end version of the manuscript, but in the .pdf form a lot of them are practically useless. The journal is publishing the figures as separate files, which can be opened and enlarged, however even in this scenario details will not be recognised from the tiny pictures. I can not judge concerning the quality of the images only from the .pdf and the authors have to be sure that the images possess enough resolution. The maps on Figures 5, 6 and 7 are not formated in a reader-friendly way. I will propose the empty northern part to be removed and the actually interesting sections to be exposed in detail. 

Response: I would like to express my sincere gratitude for your thoughtful review and valuable feedback. I apologize for any inconvenience or confusion caused by the quality of the figures in the PDF version. We fully understand your concerns regarding the clarity and resolution of the images.

Rest assured, as the journal publishes the figures as separate files, we will make certain that high-resolution original images are uploaded, allowing readers to enlarge and appreciate every detail.

Additionally, your observation about the formatting of the maps on Figures 5, 6, and 7 is well-received. We will promptly address this by removing the unnecessary northern part and emphasizing the more engaging sections for enhanced readability.

Thank you once again for your patience and insightful recommendations. We will immediately communicate with the authors to ensure all images meet the required standards and incorporate your suggestions into the final manuscript.

Figure 8 is rather confusing and I think that the authors have to chose a more logical design.

Response: Thank you for your valuable feedback regarding Figure 8. Your observation is much appreciated, and we recognize the need for a more logical and clear presentation of our data.

In order to more clearly illustrate the dynamics of suitable habitats across different climate models and time periods, we have decided to replace the existing figure with a bubble chart. In this new figure, the y-axis represents the area of highly suitable habitat, while the x-axis displays the area of moderately suitable habitat. Additionally, the size of the bubbles corresponds to the total area of suitable habitat.

We believe that this new design provides a more intuitive and comprehensible visualization of our results, allowing readers to quickly grasp the changes in habitat suitability over time and across different climate models.

Thank you again for your feedback. We hope this revision enhances the clarity and readability of our manuscript.

The discussion is too brief and in my oppinian it should include a paragraph concerning the potential of the species to migrate and the probability of leaving its current habitat and to inhabit the modeled habita in the future (from biological point of view). The conclusion is too large and confusing. In my oppinion the conclusion must be based on the local ecological legislation - what is possible to be increased in the protection according to the law and the financial instruments. All other demands are rather plakative and lack concretics (where will the funding come from, who will patrool, who will provide field work and how intensive).

Response: Thank you very much for your valuable feedback on my paper. I appreciate your comments and have made corresponding revisions based on your suggestions.

Firstly, regarding the discussion section in lines 483~496, I have incorporated additional content regarding the potential migration of the species and the likelihood of it leaving its current habitat to inhabit the modeled one in the future. Drawing from a biological perspective, I have analyzed the species' migratory patterns and capabilities, concluding that long-distance migration is highly unlikely in most scenarios, except under the unique SSP126 scenario. This addition aims to provide a more comprehensive understanding of the species' ecological behavior.

Secondly, I have revised the conclusion section to align it more closely with China's current forestry and grassland protection and development plans in lines 565~580. In the revised conclusion, I have emphasized the species' status as one of the 48 key conservation targets, highlighting the importance of its protection and population restoration. I have also specified potential funding sources, fieldwork providers, and technical support teams to ensure the practical implementation of the research findings. Additionally, I have included recommendations for forest conservation measures and specific shelters with appropriate temperature and humidity to address the species' sensitivity to winter rainfall.

Thank you again for your valuable feedback. Your suggestions have significantly improved the quality of my paper.

The text concerning the appendix 1 and 2 has to be removed and the Literature list has to be edited according to the instructions to authors - in the current form there are to many unactive links, typos and lacking of DOI.

Response: We sincerely appreciate your thoughtful feedback. As requested, we have removed the text concerning appendix 1 and 2 from the manuscript. Additionally, we have carefully revised the literature list to align with the journal's guidelines for authors, correcting inactive links, typographical errors, and adding missing DOI numbers. We are grateful for the reviewer's guidance in improving the quality of our manuscript. Thank you for your valuable time and input.

In response to your concerns regarding the English language usage in our manuscript, we have taken additional steps to ensure clarity and accuracy. We have engaged the professional editing services of LetPub, a renowned editing agency, to further refine the language of our paper. Attached is the certificate of editing as proof of their involvement.

We sincerely hope these clarifications address your concerns and look forward to your further guidance.

Best regards.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The reviewer thanks the authors for their great contribution to the revision of the manuscript, the design was improved, the text was corrected, comments and recommendations were taken into account.

The article needs some revision:

1. Line 61: Protobothrops mangshanensis, the first mention must give the full name of the species: Protobothrops mangshanensis (Zhao, 1990).

2. Overall the design is improved, but for fig. 1 I recommend making a callout (connect a line, the left geographical point on the world map with a diagram of the study area).

3. Line 480 “invasions by exotic species”, it seems to me that “exotic” should be replaced and supplemented with “aliens species and pathogens” :

 “In predicting species distribution amidst climate change, we neglected direct human interventions such as fire, logging, changes in land use, or invasions by exotic species; these factors may have affected the population in the past", in general, exclude impacts as "

4. The conclusion about the factor “amount of precipitation in the driest period” can be more clearly correlated with the data on Protobothrops mangshanensis.

Formatting:

5. Line 180, extra period: “We then used ArcGIS raster analysis tools to perform 180 a Spearman correlation analysis [24,25]. ."

Of particular interest are data on the potential habitat areas of Protobothrops mangshanensis, where individuals of this species may appear. In general, further comprehensive study of the species is necessary, and the data obtained by the authors allows us to identify priority study areas.

Author Response

Dear Reviewer,

Thank you for your valuable feedback on our manuscript. We appreciate your comments and suggestions, which have helped us improve the quality of our work.

Firstly, we would like to express our gratitude for acknowledging our efforts in revising the manuscript. We are glad that the design and text have been enhanced based on your recommendations.

Here is a response to your recommend

1. Line 61: Protobothrops mangshanensis, the first mention must give the full name of the species: Protobothrops mangshanensis (Zhao, 1990).

Response: Thank you for pointing out the need to include the full name of the species "Protobothrops mangshanensis (Zhao, 1990)" at its first mention on Line 61.

2. Overall the design is improved, but for fig. 1 I recommend making a callout (connect a line, the left geographical point on the world map with a diagram of the study area).

Response: We appreciate your suggestion to improve Figure 1 by adding a callout connecting the geographical point on the world map with the diagram of the study area.

3. Line 480 “invasions by exotic species”, it seems to me that “exotic” should be replaced and supplemented with “aliens species and pathogens” :

“In predicting species distribution amidst climate change, we neglected direct human interventions such as fire, logging, changes in land use, or invasions by exotic species; these factors may have affected the population in the past", in general, exclude impacts as "

Response:Thank you for suggesting the replacement of "exotic" with "alien species and pathogens" on Line 480. We agree that this terminology more accurately reflects the intended meaning, and we have made the corresponding modification.

4. The conclusion about the factor “amount of precipitation in the driest period” can be more clearly correlated with the data on Protobothrops mangshanensis.

Response: We are grateful for your advice to correlate the conclusion about the "amount of precipitation in the driest period" more clearly with the data on Protobothrops mangshanensis. We have revised the text to ensure a stronger connection between the data and our conclusions in lines 493~496.

Formatting:

5. Line 180, extra period: “We then used ArcGIS raster analysis tools to perform 180 a Spearman correlation analysis [24,25]. ."

Response: Thank you for noticing the extra period on Line 180. We have carefully proofread the manuscript and removed the unnecessary punctuation.

Finally, Thank you once again for your valuable feedback. We believe that your suggestions have significantly improved the quality and clarity of our manuscript.

Sincerely

Author Response File: Author Response.pdf

Reviewer 3 Report

 The revised variant of the manuscript is sufficiently improved and the authors had suxeed to illustrate their work very well. The text is also much more readable, however as I am not a native speaker I can not meet final judgment on the text quality. As editing the authors had removed all mistakes and the work seems rather complete. I recommend acceptance after proofreading.

Author Response

Dear Reviewer,

Thank you very much for your valuable feedback and recommendations on our manuscript. We are grateful for your comments, which have helped us improve the quality of our work.

We would like to inform you that we have carefully proofread the text again, paying particular attention to removing unnecessary punctuation, extra spaces, errors in capitalization, and inaccurate formatting. Your feedback has been instrumental in guiding us to refine our manuscript to the highest standards.

We are pleased to hear that the revised version of the manuscript has been sufficiently improved, and we believe we have succeeded in illustrating our work very well. The text is now much more readable, thanks to your helpful suggestions.

Although you mentioned that you are not a native speaker and therefore cannot make a final judgment on the text quality, we appreciate your honesty and recognize the value of your feedback. We have endeavored to eliminate all mistakes and ensure that the work is as complete and polished as possible.

Based on your recommendation, we are hopeful that our manuscript will be accepted after the final proofreading stage. We look forward to the opportunity to share our research with a wider audience.

Thank you once again for your time and effort in reviewing our manuscript. Your support and guidance have been invaluable to us.

Sincerely,

Author Response File: Author Response.pdf