Drought Influences Annual Survival of Painted Turtles in Western Nebraska

Round 1

Reviewer 1 Report

Please, see the attached file. 

Comments for author File: Comments.docx

Author Response

 

MATERIALS AND METHODS

• 2 Line 60: it could be better to insert a figure showing the map of the study area.
• --We have inserted a new Figure 1 with a map of the location of the study area as well as aerial photo to respond to other reviewer’s comments and suggestions. Thank you.
• 2 Lines 62-63: it is necessary to better explain the meaning of PDSI index.
• --Thank you for the suggestion. We have inserted a description in the text to explain this index.

 

CONCLUSIONS

 

• 8 Line 305. It is advisable to widen the final paragraph “Conclusions” for a better distribution of the whole manuscript. So, it necessary to report if there are similar studies in other countries worldwide. Finally, it is timely to suggest possible solutions to the problem.
• --We appreciate the suggestion. We had previously tried to emphasize the most important conclusions from our paper, but we have now added some take-home messages about other components as you requested. We did not spend time reviewing literature in this section, as we felt we had a thorough set of references to other literature throughout the rest of the Discussion section. However, we did modify the section to make it more clear about how to incorporate our work for future planning as a “solution” as you suggest.

Reviewer 2 Report

 

Drought influences annual survival of painted turtles in western Nebraska

 

Dear co-authors and editor,

 

Allyson N. Beard and colleagues provided a comprehensive study of how varies the aquatic habitat in long-term conditions of the pond turtle (Chrysemys picta). Their study compiled more than ten years of mark-recapture data, during 2005-2016, in Nebraska. Moreover, they used 14 analysis to investigate influences on population size, annual survival, among other. 

 

The aim and scope of the manuscript was clear, and in my opinion, fit with those of the journal.

 

The text is well written, although there are some typos that I annotated in the attached PDF (see my specific 33 comments).

 

The methodology of the work is appropriate, and the results presented are convincing for me. The graphics of the study are sharp, well composed, and effective. 

 

Apart from the points listed below, I annotated other things in the attached edited manuscript.

 

Sincerely,

 

 

 

 

 

Comments for author File: Comments.pdf

Author Response

Reviewer #2 replies

NOTE: all comments were made in PDF as attached comments by the reviewer. We refer to Comment Number in our replies.  We made all changes suggested unless shown below.

 

7—Suggestion was to add a comma at the location indicated, and the phrase “…distribution among habitat types…” needs to be complete phrase as the third type of impact of drought. We did not insert a comma. Please let us know if we misunderstood the request.

22—We revised this pair of sentences based on other reviewer suggestions, so the removal of the dot is no longer an issue.

23—“also documented by [43]” was suggestion.  We left it as “documented by [43]” because we did not document reduced growth of turtles. Instead, we are using that reference to the study that did document reduced growth to provide insight into the reduction in survival that we documented in this study.

26—we rewrote this sentence to avoid using a bracket citation at the beginning of a sentence.

Reviewer 3 Report

I have read the manuscript entitled “Drought influences annual survival of painted turtles in western Nebraska” by Allyson N. Beard and Larkin A. Powell, submitted to the Diversity magazine. Using mark-recapture data gathered during long-term study, Authors estimated population size and annual survival of the painted turtle (Chrysemys picta) for population in a pond in Keith County, Nebraska. Additionally, they analysed the data in context of  drought.

 

I found the results interesting – mostly data presented on the Figures 1, 2 and 3A (and the same results presented in the text). The data presented in the manuscript could be interesting for many scientists and conservationists. However, I think the version of the manuscript could be improved. I hope that the following comments can be used to improve it.

 

General remarks:
(1)
In the manuscript I have found information that (line 72) “Our study pond hosted a super-population”, but also (lines 288-289) “We have occasionally sampled in the closest ponds, yet we have never captured any painted turtles at those locations.”, and (lines 19-20) “Approximate one-fifth (temporary emigration probability: 0.19, CI = 0.16-0.23) of the population was outside the study pond at any given time.”

 

One-fifth as temporary immigration is quite large value, I think. Please forgive me for my possible misunderstanding, but based on the presented results, I am not sure how ‘migration’, ‘probability of recapture’ and ‘mortality’ during the study have been distinguished.
For example: (line 113) “We assumed γ' = γ'' for all models following”, and (lines 106-108) “(γ': the probability a marked individual will remain away from the study site during the annual time period; γ'': the probability that an individual will leave the study site).”. Is it possible to  distinguish between “the probability that an individual will leave the study site” and mortality using this method (turtles have never been captured in the closest ponds)?

 

I would like to see this problem discussed in the manuscript.
Additionally, I have found no information about other/closest population to the studied one in the manuscript. Such information in the text, or map of the study area, with information about distance to other water bodies would be really useful/crucial for the result interpretation.

(2)
lines 62-63 “During 2000-2022, the region experienced 14 years of drought (...),” however, see Figure 1. Data for years 2004–2018 are presented, and “gray shading were classified as drought years” – I have found five such years on the Figure only (i.e. years: 2005, 2006, 2013, 2014, 2015). If 2000-2003 (four seasons) and 2019-2022 (also four seasons) years were the drought years? Even if all the eight years were the “drought years”: 4 + 4 + 5 (from the figure 1) = 13 drought years, not 14 (“the region experienced 14 years of drought” – see above).

 

I believe that the answer in the Materials and method sections, mostly lines 95-100, and in the Result section, however it could be confusing for readers. Thus, it should be precisely stated which years and why were classified as the drought years in the study area, and if the classification differs from classification by the Palmer Drought Severity in the region

 

More specific comments:
-- lines (54-56): “We predicted that higher temperatures and lower pond water levels would cause lower probability of annual survival and drive movements away from our study pond, which would influence local population size estimates during drought periods.” However, I found no data on temperatures and water levels in the Result section.

 

-- line 81 “capture periods ranging from 3 to 26 days during May, June or July each year.”
3-26 days in May + 3-26 days in June + 3-26 days in June OR +3-26 days in each year (i.e. 3-26 days in May– June)? Is should be precisely stated.

 

-- lines 85-87 “We marked turtles with individual marks on marginal scutes [32], and in 2014 we began to use PIT markers as a secondary identification method.” Have you found any evidence that “marks on marginal scutes” were not readable, and PIT markers helped to identify individuals? It could be interesting for readers, I think.

 

-- lines 87-88 “We recorded carapace length (mm), mass (g), and sex [24] of each turtle before releasing to the pond [33].” I have found no analysed of such data in the manuscript. As (lines 82-83) “trapping methods limited our ability to capture turtles with lengths less than ~70mm”, and (line 189) “population size ranged from 92 (CI: 90 – 94) to 181 (CI: 175 – 186” information e.g. about proportion of small turtles (for example ~70-80 mm) would be useful  for the result interpretation.

 

-- I am not sure, but I think that not all results of performed statistical analyses are presented. For example (lines 116-118) “We assessed variation in our annual estimates of population size using a linear model (PROC GLM [40])”. Where is result of this analysis?

 

-- (line 139): “We documented 2,431 capture observations (n = 2,073, 85% recaptures)”. 2,431 observations, but n = 2,073. It should be precisely stated, as it could be confusing for readers.

 

-- Figure 1 and Figure 2. What are the whiskers on the figures? It should be stated.

 

-- (lines 189-190) “density range: 256–503 turtles/ha”. “ha” of what? the water area? ...?
See for example (lines 251-252): 22 turtles/ha of 3-ha pond (“in other studies ranged widely from 22 turtles/ha in New York (3-ha pond) to 827 turtles/ha in a 5.7-ha marsh in Michigan [26,44,45,46,47].”) Such precise information (e.g. if the density is given for 1 ha of water body) is necessary to compare the results with other studies.

 

-- lines 195-196 “Simulated mean annual survival for males ranged from 0.90 (SD = 0.02) with no drought risk to 0.84 (SD = 0.06) with a drought risk of 0.6.” If there were statistical differences in the mean annual survival for males? Result of statistical analysis of it should be presented.

 

-- (line 267) “[18] suggested that both mortality and emigration” It is not good to start sentence from “[18] suggested”, I think.

 

One more comment:
The results presented on the Figure 1 are really interesting. Why population size estimation varied in such way? See, for example, years 2011, 2012, 2013, 2014. This result should be precisely discussed, I think. Is it possible that the turtles emigrated and population size changed, or it is problem of the method? It could be interesting for many scientists, as many times one estimation on a population size is available for any population only. Authors have unique data to discuss this subject, I believe.

Author Response

(1)
In the manuscript I have found information that (line 72) “Our study pond hosted a super-population”, but also (lines 288-289) “We have occasionally sampled in the closest ponds, yet we have never captured any painted turtles at those locations.”, and (lines 19-20) “Approximate one-fifth (temporary emigration probability: 0.19, CI = 0.16-0.23) of the population was outside the study pond at any given time.”

 

One-fifth as temporary immigration is quite large value, I think. Please forgive me for my possible misunderstanding, but based on the presented results, I am not sure how ‘migration’, ‘probability of recapture’ and ‘mortality’ during the study have been distinguished.

For example: (line 113) “We assumed γ' = γ'' for all models following”, and (lines 106-108) “(γ': the probability a marked individual will remain away from the study site during the annual time period; γ'': the probability that an individual will leave the study site).”. Is it possible to  distinguish between “the probability that an individual will leave the study site” and mortality using this method (turtles have never been captured in the closest ponds)?

 

I would like to see this problem discussed in the manuscript.
--Thank you for the question.  The robust design model that we used for our analysis is an incredibly exceptional model that allows estimation—from mark-recapture data—of all of these parameters. It is able to do this because we have multiple captures within each year that provide information on population size each year (using closed population estimating model), but also captures among years that provide estimates of survival (from an open population estimating model) and the temporary emigration parameter (because of the simultaneous use of open and closed estimating models).  It is unique in that it allows you to have a single study site and estimate the proportion of the population that is outside the study site, and it was first proposed in 1992 (we cite this initial paper) and used extensively in the ecological mark-recapture literature.

--We added some clarifying text to the methods that provides a bit more detail for those not familiar with the robust design technique. However, this method is quite widespread in the mark-recapture field and there are many, many papers that have used it in similar fashion, so we did not believe a longer explanation was necessary. We are willing to add more details if you see specific needs. Thank you for asking to add more.

 

Additionally, I have found no information about other/closest population to the studied one in the manuscript. Such information in the text, or map of the study area, with information about distance to other water bodies would be really useful/crucial for the result interpretation.

--We have now added a map of the study area. Our study was limited to a single pond, but we do provide information about the distance to the nearest bodies of water in our study site description.  

 

 

(2)
lines 62-63 “During 2000-2022, the region experienced 14 years of drought (...),” however, see Figure 1. Data for years 2004–2018 are presented, and “gray shading were classified as drought years” – I have found five such years on the Figure only (i.e. years: 2005, 2006, 2013, 2014, 2015). If 2000-2003 (four seasons) and 2019-2022 (also four seasons) years were the drought years? Even if all the eight years were the “drought years”: 4 + 4 + 5 (from the figure 1) = 13 drought years, not 14 (“the region experienced 14 years of drought” – see above).

--We are sorry for the confusion here.  We were using 2000-2022 as a slightly longer, recent period to compare (and add context) to the period 2005-2016 of our study (for which your observations are indeed correct—the additional drought years during 2000-2022 were outside of our study period).  However, we have eliminated that comparison to 2000-2022 in favor of focusing on the 1950-2022 long period of reference to avoid confusion.

 

I believe that the answer in the Materials and method sections, mostly lines 95-100, and in the Result section, however it could be confusing for readers. Thus, it should be precisely stated which years and why were classified as the drought years in the study area, and if the classification differs from classification by the Palmer Drought Severity in the region

--Thank you for pointing out the need to clarify.  See response to previous statement, as we have now modified our text to clarify as you suggest.

 

More specific comments:
-- lines (54-56): “We predicted that higher temperatures and lower pond water levels would cause lower probability of annual survival and drive movements away from our study pond, which would influence local population size estimates during drought periods.” However, I found no data on temperatures and water levels in the Result section.

--We modified this line to clarify. Drought conditions are correlated with high temperatures as well as lack of precipitation. We hope the new wording is easier to understand regarding severe drought conditions with associated temperature and water level characteristics.  

 

-- line 81 “capture periods ranging from 3 to 26 days during May, June or July each year.”
3-26 days in May + 3-26 days in June + 3-26 days in June OR +3-26 days in each year (i.e. 3-26 days in May– June)? Is should be precisely stated.

--We have clarified this: “…from 3 to 26 days in each year during May, June, or July.”

 

-- lines 85-87 “We marked turtles with individual marks on marginal scutes [32], and in 2014 we began to use PIT markers as a secondary identification method.” Have you found any evidence that “marks on marginal scutes” were not readable, and PIT markers helped to identify individuals? It could be interesting for readers, I think.

--We agree this may be an interesting analysis to do in the future. We modified the wording of this sentence to note that we used the PIT markers in some situations to confirm the ID of individuals.

 

-- lines 87-88 “We recorded carapace length (mm), mass (g), and sex [24] of each turtle before releasing to the pond [33].” I have found no analysed of such data in the manuscript. As (lines 82-83) “trapping methods limited our ability to capture turtles with lengths less than ~70mm”, and (line 189) “population size ranged from 92 (CI: 90 – 94) to 181 (CI: 175 – 186” information e.g. about proportion of small turtles (for example ~70-80 mm) would be useful  for the result interpretation.

--We listed the length and mass measurements for two reasons. First, biologists commonly use the length and mass measurements to confirm identification as the data is being collected with turtle still in hand. So, we noted this information close to the identification statement in the previous sentence. Second, the length measures were used to provide the results that you quote (the fact that our data is limited to turtles of >70mm. You are correct that we did not do specific analyses using the mass and length, but we believe they are both important as a set of basic capture information that a turtle biologist would expect to see in a methods section. We can remove the mass measure if you wish, however.

--We have conducted a detailed analysis of size classes in a manuscript recently published and cited in this manuscript: Powell, L. A., Dolph, E. P., Neil, C. R. Drought affects sex ratio and growth of painted turtles in a long-term study in Nebraska. Climate Change Ecology 2023, 5, 100072. For that reason, we did not include an analysis of the length data in this paper.

 

-- I am not sure, but I think that not all results of performed statistical analyses are presented. For example (lines 116-118) “We assessed variation in our annual estimates of population size using a linear model (PROC GLM [40])”. Where is result of this analysis?

--We did provide the results to this analysis.  The full sentence from your inquiry is: “ We assessed variation in our annual estimates of population size using a linear model (PROC GLM [40]) with capture season (early summer: May, June, late summer: July August) and PHDI during the previous year as explanatory variables.”

--The results are provided at about line 196 where there is a paragraph that starts “In-pond population size ranged from…”  You will see that the population size did not vary with the two factors that we investigated, and we used the linear model for those analyses.

 

-- (line 139): “We documented 2,431 capture observations (n = 2,073, 85% recaptures)”. 2,431 observations, but n = 2,073. It should be precisely stated, as it could be confusing for readers.

--We apologize for the confusion here.  We have eliminated the portion of the sentence that was confusing as it did not add to the information needed by the reader. We had 2431 captures of 343 unique individuals—that is the important info.

 

-- Figure 1 and Figure 2. What are the whiskers on the figures? It should be stated.

--Thank you. We have added the information to the capture. They are 95% confidence intervals.

 

-- (lines 189-190) “density range: 256–503 turtles/ha”. “ha” of what? the water area? ...?
See for example (lines 251-252): 22 turtles/ha of 3-ha pond (“in other studies ranged widely from 22 turtles/ha in New York (3-ha pond) to 827 turtles/ha in a 5.7-ha marsh in Michigan [26,44,45,46,47].”) Such precise information (e.g. if the density is given for 1 ha of water body) is necessary to compare the results with other studies.

--We have added a clarification to make this clear.

 

-- lines 195-196 “Simulated mean annual survival for males ranged from 0.90 (SD = 0.02) with no drought risk to 0.84 (SD = 0.06) with a drought risk of 0.6.” If there were statistical differences in the mean annual survival for males? Result of statistical analysis of it should be presented.

--Apologies for the confusion. Now that we have added the information to the caption of the Figure 4 caption that the whiskers in Figure 4A are 95% confidence intervals, the reader can easily interpret that the declines in mean annual survival are ‘significant’.

 

-- (line 267) “[18] suggested that both mortality and emigration” It is not good to start sentence from “[18] suggested”, I think.

--We have rewritten this sentence in response to another reviewer’s comments, so the problem has been solved for your suggestion as well.

 

One more comment:
The results presented on the Figure 1 are really interesting. Why population size estimation varied in such way? See, for example, years 2011, 2012, 2013, 2014. This result should be precisely discussed, I think. Is it possible that the turtles emigrated and population size changed, or it is problem of the method? It could be interesting for many scientists, as many times one estimation on a population size is available for any population only. Authors have unique data to discuss this subject, I believe.

--We appreciate your interest in the data in this Figure. We agree. At the moment, we do not have a conclusive explanation for the changes in population size. The second paragraph of section 4.1 is where we discuss this to the extent that we can. We note: “We suspect that short-term dynamics of movement into and away from the pond are responsible for fluctuations in population size…”

Reviewer 4 Report

The study “Drought influences annual survival of painted turtles in western Nebraska” was aimed at exploring the impacts of drought conditions on freshwater turtles survival rate with emphasis on painted turtles. The study was fairly well designed but I have issues with the structural presentation of the paper.   

Outline below are some of my concerns per section.

Abstract

The abstract is fairly well written but can be improved upon. Much was not said about the data acquisition procedures.  What are the implications of drought on the survival rate of the turtles you explored? I would need to receive a more robust abstract in your resubmission.

Introduction

In lines 28-30 you stated that “Freshwater turtles are dependent on riverine or lacustrine habitats, leading to impacts of drought on movement, survival, and reproduction”. How does the dependence of freshwater turtles result in drought? Does it mean the population of freshwater turtles reduces the volume of water in an ecosystem? I am wondering how this is related to drought. The whole first paragraph is confusing to me; I would suggest you revisit and reconstruct the paragraph.  

Lines 35-36: and ~75% of turtle species are designated with a conservation status of “threatened” or more severe. What is more severe?

Overall the introduction needs a substantial improvement. Much was not said about the variation in survival rate of turtles between single and multiple seasons.

The authors referred to 15 year study on the effect of drought on the survival of turtles. I would like to know more. The authors mentioned that drought impact the seasonal mortality and pattern of distribution of freshwater turtles. How?  The arguments on the impacts of drought on the ecology of turtles were not flowing. I would like the authors to revisit the introduction section and tell us more on why they decided to carry out this study as the introduction is very short.                

Materials and methods

This section is okay. But my concern is that, how many sites were marked out for the study? Was it just one site? If so, how did you ensure the same site was visited on every sampling occasion? I am also wondering how one site can be able to tell the story of the survival rate of freshwater turtles. Note that survival rate may not only be hinged on drought, what about water quality, and possession of characteristics (traits) that may enable turtles to survival harsh weather conditions? and many more factors.

Results

I can see you are reporting results for mean, SD and SE here, but you didn’t mention them in your Analyses sub-section. Please check.

Discussion

Did you consider movement as one of the factor responsible for turtles survival rate in your study? If not, I am wondering why you are devoting a subsection in your Discussion section to movement. Please reconcile. Where you trying to say that emigration of turtles are imminent during drought conditions? If so, please help the readers to understand your story, as these were not well laid out during the introduction section.     

General comments

The authors need to revisit the manuscript from abstract to conclusion as the presentation structures lack flow. I was confused in some of the sections what the aim of the study was. See the attached document for other comments.

Comments for author File: Comments.pdf

Author Response

Reviewer #4 replies

 

COMMENTS FROM THE PDF

NOTE: Some comments were made in PDF as attached comments by the reviewer. We refer to Comment Number in our replies.  We made all changes suggested in the PDF comments unless shown below.

 

Comment #1 on PDF: The request was to inform what the cited “15-year study” was about. While we agree it would be interesting to review the information provided by all of the studies, in this sentence we were attempting to make the point that most studies (with the exception of this one) are short studies. Our study is a 12-year study, so the 15-year study is the only long-term study that we can find that address aspects of drought in the analysis.

 

Comment #3 on PDF: The request was to cite as “Steffensen et al. [38]” and to consult the author guide on citation format. We have consulted the guide, and we understand the format is to only use numbered citations with no author names in the manuscript text. If we misunderstand the format guidelines, we will be happy to reformat all of our citations.

 

Comment #8 on PDF: The request was to cite properly. We believe we did use the proper citation format, but we have rewritten the sentence so that it does not start with the citation.

 

COMMENTS IN PARAGRAPH FORM (NOT ON THE MANUSCRIPT PDF)

 

The study “Drought influences annual survival of painted turtles in western Nebraska” was aimed at exploring the impacts of drought conditions on freshwater turtles survival rate with emphasis on painted turtles. The study was fairly well designed but I have issues with the structural presentation of the paper.   

Outline below are some of my concerns per section.

 

Abstract

The abstract is fairly well written but can be improved upon. Much was not said about the data acquisition procedures.  What are the implications of drought on the survival rate of the turtles you explored? I would need to receive a more robust abstract in your resubmission.

--We added the word “captured” to our description of our data acquisition methods. We have also revised some sentences in the abstract as suggested by other reviewers. We checked our sentences in the abstract to ensure we discussed the implications of drought on survival rate. Our statement is: “Despite a relatively stable depth of water in our study pond, the probability of annual survival was reduced by 0.07 in females and 0.10 in males during drought years.”

 

Introduction

In lines 28-30 you stated that “Freshwater turtles are dependent on riverine or lacustrine habitats, leading to impacts of drought on movement, survival, and reproduction”. How does the dependence of freshwater turtles result in drought? Does it mean the population of freshwater turtles reduces the volume of water in an ecosystem? I am wondering how this is related to drought. The whole first paragraph is confusing to me; I would suggest you revisit and reconstruct the paragraph.  

--We apologize for the confusion. We have rewritten this sentence to clarify.

 

Lines 35-36: and ~75% of turtle species are designated with a conservation status of “threatened” or more severe. What is more severe?

--We rewrote this sentence and corrected the statistic when confirming with the cited paper (it is 48%).  We apologize for the lack of clarity.

 

Overall the introduction needs a substantial improvement. Much was not said about the variation in survival rate of turtles between single and multiple seasons.

--Thanks for this suggestion. The focus of our review of the literature was on variation between seasons that was caused by drought.

 

The authors referred to 15 year study on the effect of drought on the survival of turtles. I would like to know more. The authors mentioned that drought impact the seasonal mortality and pattern of distribution of freshwater turtles. How?  The arguments on the impacts of drought on the ecology of turtles were not flowing. I would like the authors to revisit the introduction section and tell us more on why they decided to carry out this study as the introduction is very short.                

-- While we agree it would be interesting to review the information provided by all of the studies cited in our introduction, in this sentence we were attempting to make the point that most studies (with the exception of this one) are short studies. Our study is a 12-year study, so the 15-year study is the only long-term study that we can find that address aspects of drought in the analysis.

--We were attempting to provide a concise introduction to the paper, and our introduction is almost two pages long when double-spaced with 12-pt font. We realize in the Diversity journal’s template it appears short, but the paper covers 13-14 journal pages as it currently sits. Because other reviewers did not comment on the brevity of the introduction, we have not increased the size. We did clarify sentences as suggested by reviewers.

 

Materials and methods

This section is okay. But my concern is that, how many sites were marked out for the study? Was it just one site? If so, how did you ensure the same site was visited on every sampling occasion? I am also wondering how one site can be able to tell the story of the survival rate of freshwater turtles. Note that survival rate may not only be hinged on drought, what about water quality, and possession of characteristics (traits) that may enable turtles to survival harsh weather conditions? and many more factors.

--You are correct that our study is based on one site. We believe our study’s strength is the long-term nature of our data across 12 years with a large sample during each year (so a trade-off of time for space in an ecological study design sense). Further, our study site had a range of drought/non-drought conditions during that time, leading to the ability to assess variation of survival as impacted by drought.

--We agree with your assertion that many other factors have the potential to affect survival, but the factor for which we had covariates to measure and report here are effects of sex and drought conditions.  

 

Results

I can see you are reporting results for mean, SD and SE here, but you didn’t mention them in your Analyses sub-section. Please check.

--We have added notes to the Method section to clarify for your suggestion, thank you.

 

Discussion

Did you consider movement as one of the factor responsible for turtles survival rate in your study? If not, I am wondering why you are devoting a subsection in your Discussion section to movement. Please reconcile. Where you trying to say that emigration of turtles are imminent during drought conditions? If so, please help the readers to understand your story, as these were not well laid out during the introduction section.     

--Thank you for your other comments regarding the Introduction section. We hope the changes we have made to the introduction are now sufficient. We note that we listed population size, survival, and movement away from the study site in our objectives section to guide the reader towards our intentions for analysis. Because movement was one of our study objectives, we dedicated the section in the Discussion.

 

General comments

The authors need to revisit the manuscript from abstract to conclusion as the presentation structures lack flow. I was confused in some of the sections what the aim of the study was. See the attached document for other comments.

--Thank you for those comments. We provided responses when necessary at the beginning of this document for the suggestions found in the PDF you provided. We made all changes unless otherwise noted.

 

Round 2

Reviewer 4 Report

Dear Authors,

 

I have now reassessed your manuscript. I am satisfied with your responses to my concerns.

 

Best of luck.