Monitoring Urban European Hares (Lepus europaeus Pallas) with Citizen Science and a Thermal Spotter

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Dear Authors,

I appreciated your study for both the relevance of the topic addressed and the robust methodology employed. I am confident that your research has generated valuable insights into the application of citizen science and the understanding of urban ecology.

However, in its current form, the manuscript is, in my opinion, not yet ready for publication due to several shortcomings.

From a general perspective, I would like to emphasize that citizen science is more than simple public engagement. In your study, certain key elements that are essential to defining a project as "citizen science" are either missing or insufficiently detailed:

• Impact on Participants: There is no discussion on the programme’s impact on the public. Even if you did not measure these impacts (e.g., through questionnaires), it would be beneficial to speculate on potential outcomes, such as enhanced education on hare biology and ecology, improved personal skills, heightened awareness of environmental issues, the development of community networks, etc.

• Data Quality Assurance: There is a lack of detail on how the quality of data provided by citizens was ensured. Were participants trained? Were supporting materials provided to guide their observations?

• Participant Retention and Engagement: Are there any data or insights regarding participant retention or their continued involvement in such activities over time?

• Recognition and Feedback: How were participants rewarded or acknowledged for their contributions? Were they informed about the study’s findings, and do you think they fully understood the significance of their role in the scientific process?

These aspects are critical for framing your study as a genuine citizen science initiative.

Additionally, it is essential to clarify that the citizen-collected data was used as an initial step in the study, which was subsequently complemented by a more traditional sampling approach involving professionals (e.g., thermal spotters). This hybrid methodology could be better emphasized in the text. I recommend reconsidering the title as it suggests a dichotomy between citizen science and the use of thermal spotters, whereas, in practice, citizens (if adequately trained) could also use such tools.

Regarding the biological and ecological aspects of the study, I believe the results are clearly presented and well-discussed. That said, it would be helpful to include some observations about potential hare refuges, particularly in areas with the highest density of sightings (e.g., residential zones with apartment blocks).

I have provided additional minor comments and corrections in the attached file for your reference.

Best regards

Comments for author File: Comments.pdf

Comments on the Quality of English Language

The English is too poor to be accepted for publication. A complete revision is needed.

Author Response

Response to Reviewer 1
1. Summary
Thank you very much for taking the time to review this manuscript. It has been very valuable for us. Please find the detailed responses below and the corresponding revisions/corrections highlighted/in track changes in the re-submitted files.
2. Questions for General Evaluation
Reviewer’s Evaluation
I appreciated your study for both the relevance of the topic addressed and the robust methodology employed. I am confident that your research has generated valuable insights into the application of citizen science and the understanding of urban ecology.
However, in its current form, the manuscript is, in my opinion, not yet ready for publication due to several shortcomings.
Thank you for your kind words, we will revise the manus according to your suggestions and respond point-by-point below.
3. Point-by-point response to Comments and Suggestions for Authors
Comments 1: From a general perspective, I would like to emphasize that citizen science is more than simple public engagement. In your study, certain key elements that are essential to defining a project as "citizen science" are either missing or insufficiently detailed:
Impact on Participants: There is no discussion on the programme’s impact on the public. Even if you did not measure these impacts (e.g., through questionnaires), it would be beneficial to speculate on potential outcomes, such as enhanced education on hare biology and ecology, improved personal skills, heightened awareness of environmental issues, the development of community networks, etc.
Response 1: Thank you for pointing this out. We partially agree with this assumption. I our study the citizens were only asked to help with data collection and no educational efforts were made during the study. We do not think that a citizens science project necessarily is educating. Although, these projects often contribute to creating knowledge about one or more species when data collection of species densities are conducted.
Comments 2: Data Quality Assurance: There is a lack of detail on how the quality of data provided by citizens was ensured. Were participants trained? Were supporting materials provided to guide their observations?
2
Response 2: We assume that hares were so distinctive and characteristic that they were not confused with other mammals as wild rabbits are not present in the area. We have added a comment on that in the manus. Among the emails sent to us with photos we did not reveal any confusion with other animals.
Comments 2. Participant Retention and Engagement: Are there any data or insights regarding participant retention or their continued involvement in such activities over time?
Response 2. The engagement of participant citizens was limited to the time it took to send an email to the researchers about the observations that they had made of hares. Citizens were not asked to look extra for hares in the two city.
Comments 3. Participant Retention and Engagement: Are there any data or insights regarding participant retention or their continued involvement in such activities over time?
Response 3. Citizens were not part of a program unless a new location was experienced citizens only reported there sightings once.
Comments 4. Recognition and Feedback: How were participants rewarded or acknowledged for their contributions? Were they informed about the study’s findings, and do you think they fully understood the significance of their role in the scientific process?
Response 4. All citizens received an answer thanking them for their report and eventually photos and we intend to inform all participants about this paper.
Comments 5. These aspects are critical for framing your study as a genuine citizen science initiative.
Response 5. We have tried to clarify the method.
Comments 6. Additionally, it is essential to clarify that the citizen-collected data was used as an initial step in the study, which was subsequently complemented by a more traditional sampling approach involving professionals (e.g., thermal spotters). This hybrid methodology could be better emphasized in the text. I recommend reconsidering the title as it suggests a dichotomy between citizen science and the use of thermal spotters, whereas, in practice, citizens (if adequately trained) could also use such tools.
Response 6. We do not think there is a basis for a complete method comparison. More areas with lawns in the city must be visited with the spotter to make a more random use of the spotter. To be honest we ran into problems interpreting the city science method and therefore tested the useability of the spotter for future studies.
4. Additional clarifications
Regarding the biological and ecological aspects of the study, I believe the results are clearly presented and well-discussed. That said, it would be helpful to include some observations about potential hare refuges, particularly in areas with the highest density of sightings (e.g., residential zones with apartment blocks).
4. Response. We have not yet focused on hare refugees. We think that the data with the spotter is too weak to make further conclusions, but we consider to conduct more hare studies in the city and may in future monitor scats from hares both to find out where hares eat and rest and use them for diet studies.
5. Additional clarifications
I have provided additional minor comments and corrections in the attached file for your reference.
5. Response
Thank you- we have used track changes in the manus for these corrections

Reviewer 2 Report

Comments and Suggestions for Authors

The literature review is relatively brief regarding the adaptation and behavioral patterns of European hares in urban environments. A more detailed comparison of hare density changes across different cities would be beneficial. Details on the parameters of the thermal imaging survey, the criteria for scanned areas, and potential biases in citizen-reported data are insufficiently discussed. There is a lack of discussion on how seasonal or climatic conditions may affect observation results. The significant discrepancy between thermal imaging and citizen science data is not analyzed in depth. Possible reasons, such as overlapping observation areas or false positives, are not explored. The ecological driving forces behind differences in habitat quality between urban centers and peripheral areas, such as green space distribution and predator presence, require further examination. Confidence intervals or error ranges are not fully annotated in the figures, which impacts the clarity of the results. The color gradients in the heat map are insufficiently detailed, affecting the readability for the audience. Some sentences are overly lengthy or syntactically awkward. For example: "However, to act as a source habitat urban area requires more than quality habitats because of increased food availability and possible increased reproduction, the advantage for hares has to be higher than the disadvantages caused by human interference..." Simplifying sentence structures would improve readability.   Specific Suggestions: Strengthen Literature Citations:   Add references to studies on the adaptability of wildlife in urban ecosystems and provide comparative data from different regions to enhance generalizability. Improve Methodology:   Provide a more detailed description of the procedures for thermal imaging and citizen science to ensure replicability. Discuss the influence of monitoring frequency, weather conditions, or terrain variability on data collection. Extend Data Analysis:   Use more sophisticated models (e.g., mixed-effects models) to explore relationships between habitat types, seasonal variations, and hare densities. Statistically analyze the causes of discrepancies between thermal imaging and citizen science data. Enhance Practical Implications of Conclusions:   In the recommendations section, elaborate on how urban green spaces can be optimized to support wildlife conservation.

Author Response

Response to Reviewer 2
1. Summary
Thank you very much for taking the time to review this manuscript. Please find the detailed responses below and the corresponding revisions/corrections highlighted/in track changes in the re-submitted files.
2. Point-by-point response to Comments and Suggestions for Authors
Comments 1: The literature review is relatively brief regarding the adaptation and behavioral patterns of European hares in urban environments. A more detailed comparison of hare density changes across different cities would be beneficial.
Response 1: Thank you for pointing this out but as we state in the manuscript there are only few papers about hares in urban areas and we have referred to and discussed these papers.
Comments 2: Details on the parameters of the thermal imaging survey, the criteria for scanned areas, and potential biases in citizen-reported data are insufficiently discussed. There is a lack of discussion on how seasonal or climatic conditions may affect observation results.
Response 2: The thermal spotter was tested in areas where people had reported hare sightings. We think that much of our figures, tables and statistics aim to discuss the biases of citizens science. We are aware of seasonal changes, but we do not have data for covering seasonal changes. It is through relevant for future studies.
Comments 2. The significant discrepancy between thermal imaging and citizen science data is not analyzed in depth. Possible reasons, such as overlapping observation areas or false positives, are not explored. The ecological driving forces behind differences in habitat quality between urban centers and peripheral areas, such as green space distribution and predator presence, require further examination.
Response 2. This is correct but we are not able to make a complete comparison between the relative data from citizens science and data from monitoring with the thermal spotter.
Comments 3. Confidence intervals or error ranges are not fully annotated in the figures, which impacts the clarity of the results. The color gradients in the heat map are insufficiently detailed, affecting the readability for the audience.
Response 3. We are sorry, but we do not agree. Confidential intervals are not relevant in the figures we have presented, and will only complicate matters. We have done the necessary statistical tests. We will change the legend colour of cementray and scrub as they are very alike.
Comments 4. Some sentences are overly lengthy or syntactically awkward. For example: "However, to act as a source habitat urban area requires more than quality habitats because
of increased food availability and possible increased reproduction, the advantage for hares has to be higher than the disadvantages caused by human interference..." Simplifying sentence structures would improve readability.
Response 4. Thank you for pointing this out. We have rephrased this section
Comments 5. Specific Suggestions: Strengthen Literature Citations: Add references to studies on the adaptability of wildlife in urban ecosystems and provide comparative data from different regions to enhance generalizability. Improve Methodology: Provide a more detailed description of the procedures for thermal imaging and citizen science to ensure replicability. Discuss the influence of monitoring frequency, weather conditions, or terrain variability on data collection.
Response 5. Thank you for pointing this out. We think that our methodology is detailed enough to replicate, but have added descriptions of how a thermal image is created. We have added a sentence pointing out that weather conditions may influence results of monitoring with the thermal spotter.
Comments 6. Extend Data Analysis: Use more sophisticated models (e.g., mixed-effects models) to explore relationships between habitat types, seasonal variations, and hare densities. Statistically analyze the causes of discrepancies between thermal imaging and citizen science data.
Response 6. We agree with the Reviewer that more sofisticated models could be interesting to apply to the dataset, and we explored the possibility of using parametric modelling. including both random and fixed effects, but they require larger sample sizes than found in our study (Bolker et al., 2009). We also explored the possibility to apply a parametric logistic regression model (generalized linear model (GLM), but also in this case the requirements of a large sample size are critical when the probability of the least frequent outcome predictor variables is low and this is our case (Bujang et al., 2018).
Therefore, in order to avoid the possibility to a type II error (false-negative), we tested the single factors separately and we obtained clear results.
The reasons for the discrepancies observed between thermal imaging and citizen science data are discussed in a qualitative way in the discussion and cannot be discussed quantitatively as they will require experimental designs where observations (made in the same places and same time interval) made by the persons could be compared with the observations made with the thermal imaging.
4. Additional clarifications Enhance Practical Implications of Conclusions: In the recommendations section, elaborate on how urban green spaces can be optimized to support wildlife conservation.
4. Response. Thank you for this suggestion, but we do not think that it is within the range of our paper, and we have no data to support management.

Reviewer 3 Report

Comments and Suggestions for Authors

Comments and Suggestions for Authors

The study explores a pertinent issue regarding the monitoring and conservation of European hares in urban environments using citizen science and thermal imaging techniques. This investigation is timely and offers potential relevance for urban wildlife management, biodiversity conservation, and ecological research. While the paper provides significant insights and valuable data, certain areas within the manuscript would benefit from further refinement and clarity.

1. The background is well-crafted, offering a historical perspective on European hare population dynamics. However, the introduction would benefit from a clearer articulation of the study’s novelty and significance compared to existing literature.

2. In the materials and methods, clarify the criteria for selecting observation points.

3. Figures and tables are generally clear but could be improved with more descriptive captions. Differentiating symbols or colors in figures for clarity would enhance understanding.

4. Integrate comparisons with similar studies from other regions to provide a broader context for your findings. This would also strengthen the paper’s discussion section.

5. The manuscript touches on ecological implications but does not fully explore management recommendations for urban planners regarding hare conservation.

6. The paper did not detail the analysis of urban green space types, vegetation coverage, and other factors affecting hare distribution, which is a direction worthy of in-depth research.

7. The authors should more clearly elaborate on potential biases and limitations of thermal imaging technology, such as the impact of nighttime temperature and obstructions on monitoring.

8. Additional references, especially on urban wildlife management and methodological advances, would bolster the manuscript’s scientific grounding.

9. Please thoroughly review and refine the formatting of the references to ensure full compliance with the journal’s guidelines.

 

 

 

Author Response

Response to Reviewer 3
1. Summary
Thank you very much for taking the time to review this manuscript. Please find the detailed responses below and the corresponding revisions/corrections highlighted/in track changes in the re-submitted files.
2. Questions for General Evaluation
The study explores a pertinent issue regarding the monitoring and conservation of European hares in urban environments using citizen science and thermal imaging techniques. This investigation is timely and offers potential relevance for urban wildlife management, biodiversity conservation, and ecological research. While the paper provides significant insights and valuable data, certain areas within the manuscript would benefit from further refinement and clarity.
3. Point-by-point response to Comments and Suggestions for Authors
Comments 1: 1. The background is well-crafted, offering a historical perspective on European hare population dynamics. However, the introduction would benefit from a clearer articulation of the study’s novelty and significance compared to existing literature.
Response 1: Thank you for pointing this out. We have added a sentence stating the relevance and novelty of this paper at the end of the introduction.
Comments 2: In the materials and methods, clarify the criteria for selecting observation points.
Response 2: Only the 12 locations visited with the thermal spotter were chosen. They were chosen to cover different city habitats and were conducted at locations with more hare sightings. This has been added to the method.
Comments 3. Figures and tables are generally clear but could be improved with more descriptive captions. Differentiating symbols or colors in figures for clarity would enhance understanding.
Response 3. Thank you for pointing this out. We will change the legend of cemeteries and scrubs which are very similar.
Comments 4. Integrate comparisons with similar studies from other regions to provide a broader context for your findings. This would also strengthen the paper’s discussion section.
Response 4. There are only three papers published about hares in other cities, and we have therefore not been able to discuss methods and densities of hares in other urban areas, also the methods used were different than ours. We have a small discussion about monitoring mammals in urban areas in general, but these methods are mostly relative regarding population density. We will add a sentence with perspectives on future studies.
Comment 5. The manuscript touches on ecological implications but does not fully explore management recommendations for urban planners regarding hare conservation.
Response 5. We have no data that will support a discussion of future urban planning regarding hare conservation. We need to explore the different urban habitats e.g. regarding diet of hares and mortality either from e.g. predation or vehicles. This is added as future studies
Comments 6. The paper did not detail the analysis of urban green space types, vegetation coverage, and other factors affecting hare distribution, which is a direction worthy of in-depth research
Response 6. This is right and that would be very interesting based on the knowledge we have now. To look into the different urban habitats and the density of hares is a hole new study and could be a relevant study in the future. As I see it it will also require botanical analysis of lawns and vegetation.
Comment 7 The authors should more clearly elaborate on potential biases and limitations of thermal imaging technology, such as the impact of nighttime temperature and obstructions on monitoring.
Response 7. Eaven during the summer at daylight the temperature of a hare being around 36-degree body temperature will exceed the summer temperatures by rarely more than 25 degrees inn Denmark. The is no chance that we overlook a hare. Rater the temperature of a warm stone maybe only a few degrees above air temperature may at first glance look like a hare, but a further inspection will reveal if it is a hare or a warm stone in hare size. We have added a short text about thermal imaging.
Comment 8 Additional references, especially on urban wildlife management and methodological advances, would bolster the manuscript’s scientific grounding.
Response 8. We have chosen some relevant papers of monitoring urban mammals in the manus.
Comment 9. Please thoroughly review and refine the formatting of the references to ensure full compliance with the journal’s guidelines.
Response 9. Thank you for pointing this out, we will check the references once more

Reviewer 4 Report

Comments and Suggestions for Authors

Review of Monitoring urban European hares (Lepus europaeus) with citizens science and a thermal spotter by Sussie Pagh et al.

This is a very interesting paper using a novel approach to monitor urban populations of a rare hare. Overall, the manuscript is in good shape but it needs some improvement on phrasing and word choice--I have offered numerous suggestions for improving the text.  I also raise some questions about methods and their interpretation for you to consider.

 

Abstract

Line 9:  Maybe a sentence that it was presumed hare populations declines also occurred in cites and urban areas.

Lines 14-16:  If higher densities were seen at the city center, how can density fall significantly with distance to the city center in both cities?  It seems conflicted.

Line 17:  “ A thermal spotter was found to be an effective and discrete…:

Line 21:  I suggest “…allowing for wild plants to establish in lawns, which benefit the hares.”

Introduction

Line 25:  “…European hare (Lepus europaeus Pallas)…”

Line 26:  strike the word ‘earliest’.  It is not needed.

Line 28: strike the word ‘have’.  Also, 5,500 years ago…

Line 31:  perhaps replace ‘natural’ with ‘native’.  Agricultural fields under any circumstances are not native.

Line 33:  “…game bag of hares has been less than 40,000 [3].”

Line 34:  I agree with you about the habitat loss, but it would seem that shooting half a million of them annually in the face of habitat loss probably was partly responsible.

Line 41-42:  “..hare (Lepus timidus L.) European rabbit (Oryctolagus cuniculus L.)…”  Also, replace ‘witness’ with ‘have reported’

Line 49-50: “Especially in the United Kingdom, other medium-sized mammals including non-native Eastern grey squirrel (Scirus carolinensis Gmelin), European hedgehog (Erinaceus europaeus L.), red fox (Vulpes vulpes L.) and European badger (Meles meles L.) are known to thrive in urban habitats [14-20].”

Line 52:  squirrels are non-native in the UK, and they are ecologically plastic tolerating urban conditions really well.  Even in their native range in the eastern US, they thrive in cities.

Line 55:  well-being.  I also suggest the following since hares were most certainly present during ancient times in what is now Aarhusa.  “In modern times, hares are known to have been present…”

Line 57:  “In the former study [13] of hares in Aarhus in 2018, the density of hares based on line transects was estimated….buildings”

Line 60: “Monitoring hares and other mammals in….”

Line 61:  suggest replacing ‘traditionally’ with ‘previously’.  Also,

“…counts, and more recently drones [fitted with cameras I presume?] have been used.”

Lines 66-69:  Please include this single sentence with the preceding paragraph.  Line 67.  “…from intensively …”  Line 69.  “…mortality.  Such monitoring data is crucial to support sound conservation planning for hares and other species”.

Line 71:  instead of ‘point out’ perhaps use ‘identify’

Methods

Liner 80: earlier in the paper you used commas to separate digits of numbers, but here you use periods.  It does not matter to me which is used, but they should all be the same.

Line 82:  “…day, and location was…”

Line 84:  Do you feel those reporting could accurately tell a leveret from an adult?  And, in general, do you have any sense of accuracy on these hare reports—possible pranks, fictitious data?  Was any attempt made to screen these data?

Line 94:  “(number of…).”

Line 103:  “…with a distance of 1 km each.” Or a total distance of 1 km? Please clarify.

Lines 109-118:  for all statistical test you should indicate the alpha level used—I assume it would be α=0.05, but I do not know that for certain.  Also, what software of program was used to conduct these analyses?

Line 113:  What is meant by ‘clocks’? Do you mean ‘circles’ or where you referring literally to time—its not clear? Also, lines 113-114, those words should not be capitalized.   Also, line 114, you should use ‘calculated’ rather than ‘estimated’.

Line 116.  Correct to ‘frequency’

Line 117-118:  I think you can safely end this sentence at ‘hares”, since you already established the areas of data collection.

Results

Line 123:  please use commas (or periods) to separate digits of numbers in order to be consistent with previous usage.

Lines 126-127:  again, do you think the ability of the general public to distinguish between a leveret and an adult is accurate?  Also, add a comma to this introductory clause: “Of the hares spotted in Aalborg,

Table 1 legend:  it appears the sample size was cut off at the end.

Section 3.1.2. starting line 136:  This is a really interesting finding and not what I would have anticipated.  I would think there would be less habitat available in the city center—especially since it happened for both cities.  Is there a chance that observer error might be involved in explaining this pattern?  In other words, were there more people reporting hares at city center, and less as the distance from center increased?  

Paragraph line 145-149:  echoing the previous comments, could your data be attributed to the human densities involved?  I would think there would be more people in apartments compared to houses with private gardens.

Lines 150-155:  a P-value of 0.01 is not highly significant--Just indicate those values were significant.

Figure 2(a):  in the methods you indicated there were 8 circles.  Here it appears there are on two complete circles and part of two others.  Where are the rest?  Probably should note this in the caption.

I’m confused.  The captions for both 2a and 2b both indicated they are citizen data from Aarhus.  How can this be? Should one be for Aalborg?

 Lines 164-166:  Most not moste.  Also, those time windows likely reflect when the citizens had time to look for the hares (before and after work, etc.), and not the activity patterns of the hares themselves.

Figure 3 caption:  Suggestion, I would say : “The horizontal arrow marks the time of day…” instead of ‘red line’ because if your paper is printed in black and white , color will be lost, and some color blind people can’t see red.  Also, ‘gray bars” not bares, and same comment about color—maybe just say vertical shading, or something similar.

Line 171:  clocks again.  By this do you mean ‘times”?

Line 172-173:  again, don’t capitalize those words in parentheses.

Line 174:  Do you mean Figure A1?

Line181:  in figure 3 you use a 24 hour clock but here you use 6 p.m. to midnight.  Maybe say 1800 to 2400 hours instead to be consistent.  Also, do you have a P-value to report for the non-significant correlation?

Line 185:  :…locations was 4 to 7 times higher than hares seen using the thermal spotter.”

Figure 4 legend: I think it would be best to simply state something such as “Photos of hares taken from video clips recorded using a thermal spotter.” The rest is irrelevant.

Discussion

Line 192:  place a question mark at end of sentence, or rewrite as ‘Urban areas are better habitats than rural habitats for hares’

Line 194:  I’d add ‘remaining’ before quality habitats.

Line 195:  I suggest adding ‘conserving’ before biodiversity.

Line 197:  are these habits truly ‘quality’ or just acceptable to the hares?

Line 198: “…conservation  value for them.”

Line 201-203:  In contrast, a Danish study in agricultural areas of Northern Jutland, hare densities…”

Line 204:  :…are more densely populated with hares…”

Line 212: “…interference (e.g., disturbance), leverets killed by cats, dogs and foxes, and mortality due to other factors such as vehicles [26,27].”

Line 215 & 217:  references cited are not done properly for journal

Line 219:  “Some animals may display increased tolerance of humans, which…”

Line 222:  “…than in urban habitats thus indicating the former populations were not conditioned to the presence of people.”

Line 231-232:  This goes back to my earlier comments on this matter.  On what basis do you conclude the number of hares observed was due to hare density rather than more observers.  This may be true but it has to be substantiated.

Line 235:  Private spelling

Line 236:  but gulls and corvids aren’t predators of hares are they?

Line 237-241  Suggest rewrite as:  “The significant declining trend in hare densities documented in this study shows a clear decline from city center outward for both cities. This declining trend may be due to composition and amount of available acceptable habitats for the hares outside of the city center.”

Line 249:  “…size, but rather they provide a relative measure to compare fox densities among habitats.”

Line 252:  “…within a city.”

Lines 255-261:  in general do not relist the figures and tables.  That was for the results section.

Line 279:  suggest “Citizen’s sightings were effect to identify locations and habitats used by hares, but they were not an appropriated method to estimate population size.”

Line 281:  “…function was shown to be a valuable…)

Line 282:  “…spotted at a distance up to 50 meters, and…”

Line 283-284:  place a comma following environments.

Line 286:  “…used over a few nights during spring and autumn, in order to estimate yearly population changes.”  [because you don’t know if it will increase or decrease]

Line 288-291.  “Cities with the proper management of green spaces may become important habitats for many different mammal species, including hares.  There is a …..benefit and conservation of wildlife.”

Line 302:  strike ‘Please add”

Appendix

Line 324, Figure A1 legend.  Start as “Correlations…”  Don’t capitalize names in parentheses.  Again, by clocks do you mean times? Also, why is this informative graph in the appendix rather than the main body of the text? Finally, please make the font size for the axes and key larger.  At least 12 point, preferably 14-16 pt

Legend for Table A1.  Suggest rewrite as “The number of hares observed at different distances from the city center to outlying areas.

Legend for Table A3.  Spell out Chi square test.  Also, it would be better to use the symbol for Chi square rather than spell it out each time (χ²)

 

 

Author Response

Response to Reviewer 4
1. Summary
Thank you very much for taking the time to review this manuscript and for the very detailed comments and corrections that are very valuable to us. Please find the detailed responses below and the corresponding revisions/corrections highlighted/in track changes in the re-submitted files.
2. Questions for General Evaluation
Reviewer’s Evaluation
This is a very interesting paper using a novel approach to monitor urban populations of a rare hare. Overall, the manuscript is in good shape but it needs some improvement on phrasing and word choice--I have offered numerous suggestions for improving the text. I also raise some questions about methods and their interpretation for you to consider.
Thank you for your kind words, we will revise the manus according to your suggestions and respond point-by-point below.
3. Point-by-point response to Comments and Suggestions for Authors
Comments 1: Line 9: Maybe a sentence that it was presumed hare populations declines also occurred in cites and urban areas.
Response 1: Thank you for pointing this out. It has been added to the abstract
Comments 2:. Lines 14-16: If higher densities were seen at the city center, how can density fall significantly with distance to the city center in both cities? It seems conflicted.
Response 2: The densities of hare observations are highest in the center of the city and it declines the further you get to the city border i.e. the city border or suburbs. We have tried to rephrase the text to make this clear.
Comments 3. Line 17: “ A thermal spotter was found to be an effective and discrete…:
Response 3. Has been rephrased in the text. We mean that the spotter will not attract public attention or as the traditional spotlights will
Comments 4. Line 21: I suggest “…allowing for wild plants to establish in lawns, which benefit the hares.”Line 25: “…European hare (Lepus europaeus Pallas)…”
Line 26: strike the word ‘earliest’. It is not needed.
Line 28: strike the word ‘have’. Also, 5,500 years ago…
Line 31: perhaps replace ‘natural’ with ‘native’. Agricultural fields under any circumstances are not native.
Line 33: “…game bag of hares has been less than 40,000 [3].”
Response 4. The suggestions have been followed and changed in the text
Comments 5. Line 34: I agree with you about the habitat loss, but it would seem that shooting half a million of them annually in the face of habitat loss probably was partly responsible.
Response 5. The papers referred to does not mention that hunting is responsible for declining population of hares. If hunting is below the “turnover” of the population it should not affect population size, but we do not have any knowledge of that. We mention in the discussion that there is no hunting in urban areas.
Comments 6.
Line 41-42: “..hare (Lepus timidus L.) European rabbit (Oryctolagus cuniculus L.)…” Also, replace ‘witness’ with ‘have reported’
Line 49-50: “Especially in the United Kingdom, other medium-sized mammals including non-native Eastern grey squirrel (Scirus carolinensis Gmelin), European hedgehog (Erinaceus europaeus L.), red fox (Vulpes vulpes L.) and European badger (Meles meles L.) are known to thrive in urban habitats [14-20].”
Line 52: squirrels are non-native in the UK, and they are ecologically plastic tolerating urban conditions really well. Even in their native range in the eastern US, they thrive in cities.
Line 55: well-being. I also suggest the following since hares were most certainly present during ancient times in what is now Aarhusa. “In modern times, hares are known to have been present…”
Line 57: “In the former study [13] of hares in Aarhus in 2018, the density of hares based on line transects was estimated….buildings”
Line 60: “Monitoring hares and other mammals in….”
Line 61: suggest replacing ‘traditionally’ with ‘previously’. Also, “…counts, and more recently drones [fitted with cameras I presume?] have been used.”
Lines 66-69: Please include this single sentence with the preceding paragraph. Line 67. “…from intensively …” Line 69. “…mortality. Such monitoring data is crucial to support sound conservation planning for hares and other species”.
Line 71: instead of ‘point out’ perhaps use ‘identify’
Liner 80: earlier in the paper you used commas to separate digits of numbers, but here you use periods. It does not matter to me which is used, but they should all be the same.
Line 82: “…day, and location was…”
Response 6. Suggestions have been made and added in the text
Comment 7. Line 84: Do you feel those reporting could accurately tell a leveret from an adult? And, in general, do you have any sense of accuracy on these hare reports—possible pranks, fictitious data? Was any attempt made to screen these data? Line 84: Do you feel those reporting could accurately tell a leveret from an adult? And, in general, do you have any sense of accuracy on these hare reports—possible pranks, fictitious data? Was any attempt made to screen these data?
Response 7. Thank you for pointing this out. We have no certain way of verifying leverets and adults other than when photos were sent. And these gave no reason to believe that leverets and adults could not be distinguished. When people reported leverets they were referring to small hares huddling up in the vegetation. Rather, young hares have been judged as adults even though they were not. We added a note in the discussion.
Comments 8. Line 94: “(number of…).”
Line 103: “…with a distance of 1 km each.” Or a total distance of 1 km? Please clarify.
Lines 109-118: for all statistical test you should indicate the alpha level used—I assume it would be α=0.05, but I do not know that for certain. Also, what software of program was used to conduct these analyses?
Line 113: What is meant by ‘clocks’? Do you mean ‘circles’ or where you referring literally to time—its not clear? Also, lines 113-114, those words should not be capitalized. Also, line 114, you should use ‘calculated’ rather than ‘estimated’.
Line 116. Correct to ‘frequency’
Line 117-118: I think you can safely end this sentence at ‘hares”, since you already established the areas of data collection
Line 123: please use commas (or periods) to separate digits of numbers in order to be consistent with previous usage.
Response 8. Changes have been made in the text
Comments 9.
Lines 126-127: again, do you think the ability of the general public to distinguish between a leveret and an adult is accurate? Also, add a comma to this introductory clause: “Of the hares spotted in Aalborg,
Response 9. We do think that the general public can distinguish an adult hare moving around from a leveret lying and huddling up in the vegetation
Comment 10.
Section 3.1.2. starting line 136: This is a really interesting finding and not what I would have anticipated. I would think there would be less habitat available in the city center—especially since it happened for both cities. Is there a chance that observer error might be involved in explaining this pattern? In other words, were there more people reporting hares at city center, and less as the distance from center increased?
Paragraph line 145-149: echoing the previous comments, could your data be attributed to the human densities involved? I would think there would be more people in apartments compared to houses with private gardens.
Response 10. It is also different from what we expected, and it does not seem to be due to the people involved, thinking that more people live in the city center- we have discussed in the discussion section. We do write densities of observations. However, the fact that duplicate locations hares are not higher apartment blocks than in areas with private gardens which are less densely populated we expect the decline in hare locations observed reflect less suitable habitats as you get nearer to the city border.
Comment 11
Table 1 legend: it appears the sample size was cut off at the end.
Lines 150-155: a P-value of 0.01 is not highly significant--Just indicate those values were significant.
Figure 2(a): in the methods you indicated there were 8 circles. Here it appears there are on two complete circles and part of two others. Where are the rest? Probably should note this in the caption.
I’m confused. The captions for both 2a and 2b both indicated they are citizen data from Aarhus.
How can this be? Should one be for Aalborg?
Lines 164-166: Most not moste. Also, those time windows likely reflect when the citizens had time to look for the hares (before and after work, etc.), and not the activity patterns of the hares themselves.
Figure 3 caption: Suggestion, I would say : “The horizontal arrow marks the time of day…” instead of ‘red line’ because if your paper is printed in black and white , color will be lost, and some color blind people can’t see red. Also, ‘gray bars” not bares, and same comment about color—maybe just say vertical shading, or something similar.
Line 171: clocks again. By this do you mean ‘times”?
Line 172-173: again, don’t capitalize those words in parentheses.
Line 174: Do you mean Figure A1?
Line181: in figure 3 you use a 24 hour clock but here you use 6 p.m. to midnight. Maybe say 1800 to 2400 hours instead to be consistent. Also, do you have a P-value to report for the non-significant correlation?
Line 185: :…locations was 4 to 7 times higher than hares seen using the thermal spotter.”
Figure 4 legend: I think it would be best to simply state something such as “Photos of hares taken from video clips recorded using a thermal spotter.” The rest is irrelevant.
Line 192: place a question mark at end of sentence, or rewrite as ‘Urban areas are better habitats than rural habitats for hares’
Line 194: I’d add ‘remaining’ before quality habitats.
Line 195: I suggest adding ‘conserving’ before biodiversity.
Response 11. It has been corrected in the text.
Comment 12. Line 197: are these habits truly ‘quality’ or just acceptable to the hares?
Response 12: We have deleted “quality” although we expect hares to be more abundant in habitats of good quality.
Comments 13. Line 198: “…conservation value for them.”
Line 201-203: In contrast, a Danish study in agricultural areas of Northern Jutland, hare densities…”
Line 204: :…are more densely populated with hares…”
Line 212: “…interference (e.g., disturbance), leverets killed by cats, dogs and foxes, and mortality due to other factors such as vehicles [26,27].”
Line 215 & 217: references cited are not done properly for journal
Line 219: “Some animals may display increased tolerance of humans, which…”
Line 222: “…than in urban habitats thus indicating the former populations were not conditioned to the presence of people.”
Line 235: Private spelling
Response 13. It has been corrected in the text.
Comment 14. Line 231-232: This goes back to my earlier comments on this matter. On what basis do you conclude the number of hares observed was due to hare density rather than more observers. This may be true but it has to be substantiated.
Response 14. We only think that citizens science will provide relative densities. The question was also - as you point out if there were more double sightings around apartment blocks with eyes than in private gardens. This does not seem to be the case. We have added observation densities when referring to citizens science.
Comment 15. Line 236: but gulls and corvids aren’t predators of hares are they?
Response 15. Gulls and corvids may predate on leverets. Corvids are known to pick out the eyes of leverets. I have a video of a herring gull killing a brown rat in Aarhus, so they will be capable to take live prey.
Comments 16. Line 237-241 Suggest rewrite as: “The significant declining trend in hare densities documented in this study shows a clear decline from city center outward for both cities. This declining trend may be due to composition and amount of available acceptable habitats for the hares outside of the city center.”
Line 249: “…size, but rather they provide a relative measure to compare fox densities among habitats.”
Line 252: “…within a city.”
Lines 255-261: in general do not relist the figures and tables. That was for the results section.
Line 279: suggest “Citizen’s sightings were effect to identify locations and habitats used by hares, but they were not an appropriated method to estimate population size.”
Line 281: “…function was shown to be a valuable…)
Line 282: “…spotted at a distance up to 50 meters, and…”
Line 283-284: place a comma following environments.
Line 286: “…used over a few nights during spring and autumn, in order to estimate yearly population changes.” [because you don’t know if it will increase or decrease]
Line 288-291. “Cities with the proper management of green spaces may become important habitats for many different mammal species, including hares. There is a …..benefit and conservation of wildlife.”
Line 302: strike ‘Please add”
Response 16. The suggestions have been followed.
Comments 17. Line 324, Figure A1 legend. Start as “Correlations…” Don’t capitalize names in parentheses. Again, by clocks do you mean times? Also, why is this informative graph in the appendix rather than the main body of the text? Finally, please make the font size for the axes and key larger. At least 12 point, preferably 14-16 pt
Legend for Table A1. Suggest rewrite as “The number of hares observed at different distances from the city center to outlying areas.
Legend for Table A3. Spell out Chi square test. Also, it would be better to use the symbol for Chi square rather than spell it out each time (χ2)
Response 17. Suggestions have been followed and changed in the text. We have moved figure A1 to the main body text.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

he authors have thoroughly addressed the comments I raised during the review process and made careful revisions to the manuscript. After reviewing the revised version, I believe it meets the publication standards, with scientifically rigorous content, reasonable analysis, and significant academic value. I am pleased to recommend its acceptance for publication.