Stakeholder Perspectives on Zoo Sound Environments and Associated Impacts on Captive Animal Behaviour, Management and Welfare

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This paper clearly describes the process, conclusions, and implications of a small workshop in the UK on how sound is and should be considered in zoo and aquarium animal management. The workshop was well-structured and attendance represented a good variety of roles within UK zoos as well as few zoo-focused academics. The authors do an excellent job of summarizing the broad themes and conclusions from the workshop and supplement the conclusion on taxonomic gaps with information from a more recent lit search. I particularly appreciated their framing of sound as "both a risk and a resource"

Given that the primary data are drawn from a small group of folks working in and with UK zoos, I have four suggestions for improving the paper:

1) The reporting of results seems unnecessarily long and detailed. The authors should retain their lovely summaries in the paper and move the "raw data" from the working group report-outs (Tables 1-3) to supplemental materials. If they want to keep some taxon-specific data in the paper, creating a summary table comparing and contrasting findings across the different taxa could be useful.

2) The authors had a great idea to conduct a lit search to bring the workshop results into context! However, I was disappointed that the only data presented from that lit was taxonomic. Could the authors address whether any of the other major gaps identified in the workshop were addressed by these more recent papers?

3) In the discussion, the authors sometimes lose track of the context of their data. Up through line 375, they do an excellent job of reminding us that what they are reporting are the views of the workshop delegates. But then they seem to assume that if the delegates don't know an answer, no one does. This is simply not true! In many cases - for example the sensory systems of many invertebrates and herpetiles - conducting more research to fill the gaps identified by workshop delegates would simply be reinventing the wheel. Folks outside of the zoo community or at zoos outside the UK have a vast amount of both empirical and applied knowledge that could answer these questions. In addition to calling for more research, the authors should acknowledge that zoos often have difficulty getting and using relevant information even when it already that exists in the scientific literature or in the international zoo community. Are there particular gaps the delegates identified where this is the case? Are there ways the zoo community could or is moving towards keeping better track of the science? The AZA's Animal Welfare Committee's monthly bibliography of zoo-relevant publications might be a good example. 

4) In both the findings summary and the discussion, the authors correctly note that psychological variables including learning histories affect how animals sense and respond to their soundscapes. I was excited to see the mentions of control and predictability in the discussion, but three other key variables were present in the delegates comments and omitted: associative learning (e.g., sound cues for important events), perceptual abilities (e.g., what the animal can and cannot detect), and choice (e.g., sound retreats that would allow animals to escape from sounds they cannot control = turn off). These three variables should be added to the discussion of control and predictability.

Author Response

Responses to reviewer 1

This paper clearly describes the process, conclusions, and implications of a small workshop in the UK on how sound is and should be considered in zoo and aquarium animal management. The workshop was well-structured and attendance represented a good variety of roles within UK zoos as well as few zoo-focused academics. The authors do an excellent job of summarizing the broad themes and conclusions from the workshop and supplement the conclusion on taxonomic gaps with information from a more recent lit search. I particularly appreciated their framing of sound as "both a risk and a resource"

Thank you for the kind remarks on the relevance of our paper. We have attempted to clarify all areas noted and have responded to all edits. We appreciate the time taken to review our work.

Given that the primary data are drawn from a small group of folks working in and with UK zoos, I have four suggestions for improving the paper:

1) The reporting of results seems unnecessarily long and detailed. The authors should retain their lovely summaries in the paper and move the "raw data" from the working group report-outs (Tables 1-3) to supplemental materials. If they want to keep some taxon-specific data in the paper, creating a summary table comparing and contrasting findings across the different taxa could be useful.

Thank you for the feedback. We have removed Tables 1-3 from the main manuscript and included these in the supplementary information as Tables S1 to S3. We have provided a short, written description of the content of each table in the main text and this is highlighted in yellow, from lines 214-302. We already have the comparison in (what are now) Tables 1 and 2 and so we do not believe further comparative description is now needed.

 

2) The authors had a great idea to conduct a lit search to bring the workshop results into context! However, I was disappointed that the only data presented from that lit was taxonomic. Could the authors address whether any of the other major gaps identified in the workshop were addressed by these more recent papers?

Thank you for the comment. We are pleased that you find the literature review useful. We have expanded the description of this sample of papers to show trends in topics published on, as well as potential gaps that still need filling. This is highlighted in yellow under Table 3. We have also extended the discussion (please see lines 534-543) to show the overall topic trends and areas of research focus from this mini review. Some of the directions taken in the more recent literature are relevant to issues raised by participants in the workshops, such as guidance on conducting sonic research in zoos and research that suggests ways of considering sound in future enrichment design for zoo-housed species.

3) In the discussion, the authors sometimes lose track of the context of their data. Up through line 375, they do an excellent job of reminding us that what they are reporting are the views of the workshop delegates. But then they seem to assume that if the delegates don't know an answer, no one does. This is simply not true! In many cases - for example the sensory systems of many invertebrates and herpetiles - conducting more research to fill the gaps identified by workshop delegates would simply be reinventing the wheel. Folks outside of the zoo community or at zoos outside the UK have a vast amount of both empirical and applied knowledge that could answer these questions. In addition to calling for more research, the authors should acknowledge that zoos often have difficulty getting and using relevant information even when it already that exists in the scientific literature or in the international zoo community. Are there particular gaps the delegates identified where this is the case? Are there ways the zoo community could or is moving towards keeping better track of the science? The AZA's Animal Welfare Committee's monthly bibliography of zoo-relevant publications might be a good example. 

Thank you for the feedback and suggestions. We have refined this area of the discussion to cover the ideas suggested by the reviewer. Please see this section in yellow, line 444 onwards. We have included new examples and ideas for collaboration to help provide in situ research findings more frequently within ex situ applications.

 

4) In both the findings summary and the discussion, the authors correctly note that psychological variables including learning histories affect how animals sense and respond to their soundscapes. I was excited to see the mentions of control and predictability in the discussion, but three other key variables were present in the delegates comments and omitted: associative learning (e.g., sound cues for important events), perceptual abilities (e.g., what the animal can and cannot detect), and choice (e.g., sound retreats that would allow animals to escape from sounds they cannot control = turn off). These three variables should be added to the discussion of control and predictability.

Thank you for the feedback. We have included a further detail in the discussion that expand on association between a sound and a potential experience, understanding of perception of sound, and how to provide choice for an animal to remove themselves from unwanted sounds (e.g., through enclosure design and furnishing). Please see the yellow highlighted section, lines 498-515.

Reviewer 2 Report

Comments and Suggestions for Authors

See attached document for feedback.

Comments for author File: Comments.docx

Author Response

This was a very unique manuscript to review, as it does not fall under the two most typical formats – research article or review. While I think it is a good idea to share out the findings of a closed workshop like this (since it wasn’t a part of a larger conference and wouldn’t be capturing in something like conference proceedings necessarily), I don’t think that it fit very cleanly into format of a traditional research article in terms of an actual manuscript. One could argue that it is a form of qualitative research, but if that is the case then the methods certainly were not rigorous enough. But, I presume, that was not the point of the workshop (rigorous data collection), but rather a series of collaborative discussions of subject matter experts. Unfortunately, that does make it read like an attempt to shoehorn qualitative discussions into a format meant for quantitative data. Ultimately, given the agreed upon importance of what was discussed and the relative lack of research on the topic, it is my opinion that the positives of the manuscript outweigh the negatives (the content of the manuscript not necessarily meshing with the required format), and I will leave it up to the editors to decide whether or not this fits within the journal’s desired formats.

I think that certain ideas/concepts shared by the authors from the workshop are really interesting, such as noise from daily husbandry activities (closing doors, gates, etc.), as that is an area of sound and welfare research that is largely ignored, instead focusing on visitor noises or large nighttime events, like concerts. Another concept that came to light from this workshop was the idea of auditory shift, or that the welfare impacts of sound likely change with age and life stage, and I think this is another area worthy of further research. Another idea that was identified that I think is worth highlighting and pursuing further research is how best to quantify the impact of sound on cryptic species, as there inactivity/cryptic behavior could be attributed to their natural history and not any outer sonic impacts.

I felt that the Results section became overwhelming with the large tables, Tables 4 and 5 in particular. Since the content in these tables is written in paragraph form, it is essentially no different than the normal text of the manuscript, just broken into different “categories” by the table. To increase readability, I would recommend trying to shorten the information shared in the right hand columns with bullet points, or space them out into separate thoughts/sentences like you did in the earlier tables. Tables 4 and 5 also feel repetitive to me, as they are both attempts to sort of summarize all of the information shared in the workshop. So is Table 4 meant to summarize commonalities from discussions from the different taxa group discussions, and then Table 5 is summarizing general outputs from the workshop as a whole? There were other aspects of the manuscript that appeared repetitive, such as the bullet points listed under section 4.1. A lot of the information within these bullets is lifted pretty directly from Tables 4 and 5, which makes relisting them here unnecessary. They should certainly be referenced, but I would prefer to see expanding upon these points in the Discussion section, rather than listing them out again in slightly different words before getting into any analysis or discussion.

One final aspect that I think would help strengthen this paper would be more specific recommendations on next steps, in the authors’ opinions, in sound/welfare research based on the results of this workshop and literature review. While I presume that the primary objective of this manuscript is to share out information from the workshop, I think that this paper would benefit from the specific identification of items or concepts derived from the main themes of the workshop that are in need of research in the near future. Both the workshop and the lit review should give the authors a good perspective on what is needed and what is missing in the published literature, and establish credibility for them to make recommendations for what the biggest needs are in this specific field of research. Adding some sort of section on future directions or recommendations would really benefit the discussion section of the paper, as current it reads a bit repetitive, sort of re-summarizing and discussing the main themes of the workshop in slightly different ways (the word clouds being one example of a slightly different format to share the main themes summarized in earlier tables).

Below I’ve included a handful of edits/comments on specific lines, and I appreciated the opportunity to review a very different format of paper on what sounds like a very interesting workshop.

 

• Line 43: Is the phrase in parentheses meant to that certain stimuli are outside the control of their caretakers, in addition to themselves, or that their caretakers are an additional stimulus that animals are exposed to? I’m assuming the former, given the context of the paper, but it did read a bit confusing to me.

This was a very unique manuscript to review, as it does not fall under the two most typical formats – research article or review. While I think it is a good idea to share out the findings of a closed workshop like this (since it wasn’t a part of a larger conference and wouldn’t be capturing in something like conference proceedings necessarily), I don’t think that it fit very cleanly into format of a traditional research article in terms of an actual manuscript. One could argue that it is a form of qualitative research, but if that is the case then the methods certainly were not rigorous enough. But, I presume, that was not the point of the workshop (rigorous data collection), but rather a series of collaborative discussions of subject matter experts. Unfortunately, that does make it read like an attempt to shoehorn qualitative discussions into a format meant for quantitative data. Ultimately, given the agreed upon importance of what was discussed and the relative lack of research on the topic, it is my opinion that the positives of the manuscript outweigh the negatives (the content of the manuscript not necessarily meshing with the required format), and I will leave it up to the editors to decide whether or not this fits within the journal’s desired formats.

I think that certain ideas/concepts shared by the authors from the workshop are really interesting, such as noise from daily husbandry activities (closing doors, gates, etc.), as that is an area of sound and welfare research that is largely ignored, instead focusing on visitor noises or large nighttime events, like concerts. Another concept that came to light from this workshop was the idea of auditory shift, or that the welfare impacts of sound likely change with age and life stage, and I think this is another area worthy of further research. Another idea that was identified that I think is worth highlighting and pursuing further research is how best to quantify the impact of sound on cryptic species, as there inactivity/cryptic behavior could be attributed to their natural history and not any outer sonic impacts.

Thank you for the suggestion. We have included information on individual responses and also different species ecological traits. 

I felt that the Results section became overwhelming with the large tables, Tables 4 and 5 in particular. Since the content in these tables is written in paragraph form, it is essentially no different than the normal text of the manuscript, just broken into different “categories” by the table. To increase readability, I would recommend trying to shorten the information shared in the right hand columns with bullet points, or space them out into separate thoughts/sentences like you did in the earlier tables. Tables 4 and 5 also feel repetitive to me, as they are both attempts to sort of summarize all of the information shared in the workshop. So is Table 4 meant to summarize commonalities from discussions from the different taxa group discussions, and then Table 5 is summarizing general outputs from the workshop as a whole? There were other aspects of the manuscript that appeared repetitive, such as the bullet points listed under section 4.1. A lot of the information within these bullets is lifted pretty directly from Tables 4 and 5, which makes relisting them here unnecessary. They should certainly be referenced, but I would prefer to see expanding upon these points in the Discussion section, rather than listing them out again in slightly different words before getting into any analysis or discussion.

Thank you for the comment. Tables 4 and 5 are now 1 and 2 and have been kept based on other reviewer feedback. Other tables have been moved to the supplementary information to make the results section more smooth and accessible when reading.

One final aspect that I think would help strengthen this paper would be more specific recommendations on next steps, in the authors’ opinions, in sound/welfare research based on the results of this workshop and literature review. While I presume that the primary objective of this manuscript is to share out information from the workshop, I think that this paper would benefit from the specific identification of items or concepts derived from the main themes of the workshop that are in need of research in the near future. Both the workshop and the lit review should give the authors a good perspective on what is needed and what is missing in the published literature, and establish credibility for them to make recommendations for what the biggest needs are in this specific field of research. Adding some sort of section on future directions or recommendations would really benefit the discussion section of the paper, as current it reads a bit repetitive, sort of re-summarizing and discussing the main themes of the workshop in slightly different ways (the word clouds being one example of a slightly different format to share the main themes summarized in earlier tables).

Thank you for the review of the paper. It has been substantially revised based on the comments of multiple reviewers. We hope that our responses provide further clarity and answer your questions on our paper. We have edited sections to reduce repetition and also extend elements of discussion identified by other reviewers. We have also removed some tables to supplementary information and expanded on the types of species for future focus (e.g., those that are camouflaged). We appreciate the time taken for your review and hope that you can read over the new sections (in yellow highlight) that answer the points in the discussion above.

Below I’ve included a handful of edits/comments on specific lines, and I appreciated the opportunity to review a very different format of paper on what sounds like a very interesting workshop.

• Line 43: Is the phrase in parentheses meant to that certain stimuli are outside the control of their caretakers, in addition to themselves, or that their caretakers are an additional stimulus that animals are exposed to? I’m assuming the former, given the context of the paper, but it did read a bit confusing to me.

Thank you for the feedback. The abstract has been completely unchanged and now this section is removed. However, we hope the abstract is much clearer in meaning.

• Line 124: Did everyone who was on the original invitation to the workshop fall into the same categories of work responsibilities/job titles as those who ended up attending? I ask because, beyond the zoo membership organization manager, all attendees sort of fall into the same world of biology/research/animal focus. The are other, non-animal focused jobs in the zoo (facilities management, consumer events, guest experience, etc.) whose jobs often involve the creation/mitigation of anthropogenic noise. Were upper level zoo administration or management individuals were solicited? These individuals typically make the final call on any larger issues that involve sound and animal welfare (especially when it may impact revenue generation), so I would’ve been interested in those positions’ “sonic awareness”

Thank you for the feedback. We have expanded on why these delegates were chosen but we wanted a breadth of zoo personnel who worked with animals and for zoos, to capture how sound might be considered (or not) so as to guide future decisions. The next step for this type of activity would be to focus on those who could initiative any changes to management now that we have identified what may need to be better considered in zoo operations. We specifically included colleagues from zoo membership/accreditation bodies to capture the overview perspective of zoo operations and who could have influence at a higher level.

• Table 6: For the “Up to and including 2019” category, how far back did the lit review reach, or what was the earliest published sound-related paper found?

Thank you for the feedback. This section has been edited to provide dates.

• Line 300: While I don’t doubt that the word “noise” did come up a lot, I’m not sure if sharing out that “noise” was one of the most used words at a workshop all about the zoo soundscape is really worth sharing out. The other four words to convey some interesting insights though. The fact that “enclosure design” is so dominant suggests that there is a desire/need to be proactive in the initial design process about sound mitigation (or perhaps sound production, to build in avenues/devices for auditory enrichment), when I see that most of the studies investigating sound and welfare are reactive.

Thank you for the feedback. We do not wish to edit out what delegates said. And this was a word that was reported a lot. Given its subjectivity and need for clarification and validation, we believe it is important to keep this in and show that people can use the term noise even when it has a vague overall meaning. We have explained the key outputs from these word clouds to provide more objectivity on the responses.

• Line 355: Perhaps identify which stakeholders (roles, job, etc.) should be included in the collaborative approach to addressing these challenges? Was this a topic discussed during the workshop?

Thank you for the feedback. We have recommended more collaborative discussion and that in situ experts and those who can foster relationships across parties be included, but we do not wish to be prescriptive.

• Line 124: Did everyone who was on the original invitation to the workshop fall into the same categories of work responsibilities/job titles as those who ended up attending? I ask because, beyond the zoo membership organization manager, all attendees sort of fall into the same world of biology/research/animal focus. The are other, non-animal focused jobs in the zoo (facilities management, consumer events, guest experience, etc.) whose jobs often involve the creation/mitigation of anthropogenic noise. Were upper level zoo administration or management individuals were solicited? These individuals typically make the final call on any larger issues that involve sound and animal welfare (especially when it may impact revenue generation), so I would’ve been interested in those positions’ “sonic awareness”.

Thank you for the feedback. We wished to chose a group of delegates with experience of animal care, management and zoo operations. We included those who work for zoo membership/accreditation bodies to gain the perspective of these with an overview of how zoos "work" and who could influence higher level management. Of course, such participants could be included in any future workshop that has built on our ideas, and we have recommended this in our discussion.

• Table 6: For the “Up to and including 2019” category, how far back did the lit review reach, or what was the earliest published sound-related paper found?

Thank you for the feedback. This has been edited according to other reviewer feedback.

• Line 300: While I don’t doubt that the word “noise” did come up a lot, I’m not sure if sharing out that “noise” was one of the most used words at a workshop all about the zoo soundscape is really worth sharing out. The other four words to convey some interesting insights though. The fact that “enclosure design” is so dominant suggests that there is a desire/need to be proactive in the initial design process about sound mitigation (or perhaps sound production, to build in avenues/devices for auditory enrichment), when I see that most of the studies investigating sound and welfare are reactive.

We are not sure of the reviewer's edit here, however the other reviewers believed it was useful to note the subjectivity of noise and asked us to extend our explanation of this in the introduction and the discussion, so we wish to keep this as is.

• Line 355: Perhaps identify which stakeholders (roles, job, etc.) should be included in the collaborative approach to addressing these challenges? Was this a topic discussed during the workshop

Thank you for the feedback, we have recommended that a wider range of stakeholders could be included but we do not think we should be prescriptive in who should attend as we attempted to include variety in the original delegate list.

 

Reviewer 3 Report

Comments and Suggestions for Authors

The paper, titled "Stakeholder perspectives on zoo sound environments and associated impacts on captive animal behaviour, management and welfare" addresses an important and timely topic. I found the subject matter of the article fascinating and read the manuscript with great intrest. The paper aligns well with the scope of the journal, no question about that.

Main Research Question

The core question driving this research is how various stakeholders within the zoo community perceive and consider the sound environments of zoos, and the subsequent impacts on captive animal behavior, management, and welfare. They're really trying to get a handle on what zoo professionals are thinking and doing about sound.

Originality and Relevance

I definitely consider this topic highly original and exceptionally relevant to the field. While there's been some focus on noise and its effects, this paper really dives into the perceptions of those on the ground – the keepers, welfare officers, and designers. That's a crucial, often overlooked gap. We need to know where the knowledge gaps are from a practical standpoint to target future research effectively. It's not just about if sound is an issue, but if people think it is, and what they do about it. The multi-stakeholder workshop approach is quite fresh, too.

Contribution to the Subject Area

Compared to other published material, this paper adds a really valuable stakeholder-centric perspective. Most research looks at specific species responses or sound measurements. This, however, provides a snapshot of the human element in zoo sound management. It highlights areas where staff are conscious of sound, but also where their knowledge is limited, particularly regarding less-studied taxa like reptiles, amphibians, fish, and invertebrates. It's not just more data on animal responses, but a crucial look at the awareness and practices currently in place, which is quite distinct and very useful for guiding future applied research.

However, I believe that in its current form, it has several shortcomings that kinda hold it back a bit.

Just a heads-up, the abstract seems a tiny bit long. It covers a lot, which is good, but maybe a slight trim to make it more punchy could be helpful. Also, I noticed a few inconsistent capitalisations for "zoo" throughout the document; it sometimes appears as "Zoo" and sometimes as "zoo". A quick pass to make this uniform would be good.

Introduction

The introduction sets the stage well, highlighting the growing interest in sound and its impact on zoo animals. One minor thought, perhaps the paper could benefit from an even clearer, albeit brief, acknowledgment of the challenge of defining "noise" early on, even before the discussion section. While the discussion addresses this thoroughly, a quick nod to its inherent subjectivity at the outset might frame the entire piece more robustly, as it's such a central concept.

Line 18: "intrest" should be "interest". Also, the phrasing "no question about that" feels a little casual for a formal paper; maybe reword it slightly to maintain a more academic tone.

Line 39: The keyword "environment" is listed; perhaps "sound environment" or "acoustic environment" would be more specific and helpful for indexing.

Materials and Methods

The methodology for gathering stakeholder perspectives is generally sound, but I do have a few points about it. The relatively small number of delegates (12 from 20 invited) raises questions about the generalisability of the findings, even for a qualitative study; perhaps a more detailed explanation of why these specific individuals were chosen, beyond their expertise, could be useful. It's also worth noting the workshop was in March 2020 – just as the world was getting a bit chaotic – though the authors mention "untoward circumstances," it might be worth a small reflection on any potential wider impact on participant focus, if any was observed. Regarding the data analysis, the process for summarising key terms and phrases (lines 137-142) relies heavily on subjective interpretation, which is fine for qualitative work, but a more explicit statement on how inter-rater reliability was ensured or disagreements resolved could add rigor. Finally, the decision to group several diverse taxa (reptiles/amphibians and fish/invertebrates) due to "budgetary and logistical constraints" (lines 160-162) is completely understandable but is a pretty significant methodological limitation that should be emphasised more prominently in the discussion.

Line 112: "veterinary surgeon" could just be "veterinarian" for conciseness, though "veterinary surgeon" isn't wrong.

Line 138: "main investigator" is used. It might be better to consistently refer to the specific author (e.g., "the first author" or "Dr. Rose") to avoid ambiguity.

Line 142: "further inferential analysis was attempted" – "was attempted" feels a bit passive. "no further inferential analysis was conducted" might flow a bit better.

Line 161: "untoward circumstances" is a very polite way to put it, and accurate for March 2020! Just make sure that's the intended level of formality.

Line 189: "Web of Science database (webofscience.com)" - The URL doesn't really need to be there. Just "Web of Science database" is sufficient.

Results

The results section provides a wealth of information from the workshop, which is great. The tables (Tables 1, 2, 3) are quite informative, though sometimes the formatting makes them a bit dense; maybe breaking down some of the longer bullet points or using slightly more concise language could improve readability. My main comment here, however, concerns the word clouds (Figures 1 and 2). While they offer a nice visual summary, the statement that they were "generated with assistance from ChatGPT (OpenAI, 2025)" is a bit jarring for a scientific publication. It would be better to describe the process by which the word clouds were created (e.g., using specific text analysis software to identify frequent terms) rather than attributing it to an AI model, especially a recent one, as some readers might question the analytical independence or methodological robustness.

Table 1: Some of the entries under "Do consider sound" are a little vague (e.g., "Hard to think of what is done" or "unsure of its biological relevance"). While these are direct quotes from delegates, maybe adding a small parenthetical note to clarify that these reflect the reported lack of existing practice rather than an authorial statement would be useful for the reader.

Table 2: "Taxonomic order" as a heading for the first column is a bit off, since it lists groups like "Birds" and "Mammals" rather than strict taxonomic orders. "Taxonomic Group" would be more accurate.

Line 207: "Table 1 presents responses from workshop delegates summarising where sound is currently considered..." - This sentence is a bit long. Consider breaking it up or rephrasing for improved flow.

Lines 335 and 339: The reference to "ChatGPT (OpenAI, 2025)" for word cloud generation might be better rephrased. For example, you could state "Word clouds were generated using text analysis software (e.g., [Software Name if applicable]) to identify frequent terms." This maintains academic rigor and avoids potential distraction for some readers.

Discussion

The discussion does a commendable job of linking the workshop outputs with existing literature and exploring the nuances of sound perception and management in zoos. I found the section on the definition of "noise" (lines 403-417) particularly insightful and well-articulated. The conclusions drawn are largely consistent with the evidence presented from the workshop discussions and the brief literature review. The paper addresses the main question posed by clearly outlining the current state of stakeholder awareness and practice regarding zoo sound environments. However, the limitations stemming from the small sample size and the necessary grouping of taxa in the workshop should be more explicitly discussed here, perhaps with a paragraph dedicated to how these factors might influence the breadth and generalizability of the findings. This would strengthen the paper's overall scientific argument.

Line 370: "ecotherms" should be "ectotherms." A small typo there.

Line 391: "four animals for example)" seems to have a stray parenthesis. Should probably be "four animals (for example) in the same enclosure..." or similar.

Line 403: The use of quotes around "noise" (e.g., "what we mean by “noise”?") is good for emphasis, but ensure consistency throughout the paragraph; sometimes it's quoted, sometimes not.

Line 443: "refuted with empirical evidence from research at the zoo" - maybe "supported or nuanced by empirical evidence" rather than "refuted," as 'refuted' can sound quite strong.

Conclusions

The conclusions effectively summarise the key findings and their broader implications. They align well with the evidence, advocating for formal integration of sound into welfare planning, which is a strong take-home message. I think the final paragraph could perhaps reiterate even more strongly how the stakeholder perspective itself is a unique contribution, reinforcing why this approach was so valuable.

Line 470: "those for reptiles, amphibians, fish and invertebrates" might read slightly better as "particularly for reptiles, amphibians, fish, and invertebrates."

To enhance the paper's broader applicability, I recommend citing the recently published review by El-Sabrout et al. (2024), "Environmental Enrichment in Rabbit Husbandry: Comparative Impacts on Performance and Welfare," in the Conclusions section, specifically around lines 481-485. This manuscript provides an excellent example from another managed animal industry—rabbit farming—where the control of environmental stimuli is paramount for animal welfare. Including this reference would effectively strengthen the argument that the principles of managing sensory environments, though discussed here in a zoo context, have widespread relevance across diverse animal care settings, thus reinforcing the paper's overarching message about the importance of holistic and evidence-informed approaches.

References

The references appear appropriate and cover a good range of relevant literature. I've noted a few recent publications, which is excellent. I didn't spot any major omissions or inconsistencies in the citation style, though a thorough check for uniform formatting would always be prudent during final edits.

 

Author Response

Replies to reviewer 2

The paper, titled "Stakeholder perspectives on zoo sound environments and associated impacts on captive animal behaviour, management and welfare" addresses an important and timely topic. I found the subject matter of the article fascinating and read the manuscript with great intrest. The paper aligns well with the scope of the journal, no question about that.

Thank you for the positive feedback. We appreciate the useful areas for development noted in your feedback.

Main Research Question

The core question driving this research is how various stakeholders within the zoo community perceive and consider the sound environments of zoos, and the subsequent impacts on captive animal behavior, management, and welfare. They're really trying to get a handle on what zoo professionals are thinking and doing about sound.

Originality and Relevance

I definitely consider this topic highly original and exceptionally relevant to the field. While there's been some focus on noise and its effects, this paper really dives into the perceptions of those on the ground – the keepers, welfare officers, and designers. That's a crucial, often overlooked gap. We need to know where the knowledge gaps are from a practical standpoint to target future research effectively. It's not just about if sound is an issue, but if people think it is, and what they do about it. The multi-stakeholder workshop approach is quite fresh, too.

Thank you for the positive feedback, we appreciate the thoughtful review.

Contribution to the Subject Area

Compared to other published material, this paper adds a really valuable stakeholder-centric perspective. Most research looks at specific species responses or sound measurements. This, however, provides a snapshot of the human element in zoo sound management. It highlights areas where staff are conscious of sound, but also where their knowledge is limited, particularly regarding less-studied taxa like reptiles, amphibians, fish, and invertebrates. It's not just more data on animal responses, but a crucial look at the awareness and practices currently in place, which is quite distinct and very useful for guiding future applied research.

However, I believe that in its current form, it has several shortcomings that kinda hold it back a bit.

Just a heads-up, the abstract seems a tiny bit long. It covers a lot, which is good, but maybe a slight trim to make it more punchy could be helpful. Also, I noticed a few inconsistent capitalisations for "zoo" throughout the document; it sometimes appears as "Zoo" and sometimes as "zoo". A quick pass to make this uniform would be good.

Thank you for the feedback. We have reduced the length of abstract and attempted to make it more concise. The new abstract is highlighted in yellow.

We have been through the entire document, and we cannot see where the inconsistency in capitalisation of the word zoo is. Unless we refer to the name of a specific establishment, e.g., Bristol Zoo, the word zoo has a lower case z.

 

Introduction

The introduction sets the stage well, highlighting the growing interest in sound and its impact on zoo animals. One minor thought, perhaps the paper could benefit from an even clearer, albeit brief, acknowledgment of the challenge of defining "noise" early on, even before the discussion section. While the discussion addresses this thoroughly, a quick nod to its inherent subjectivity at the outset might frame the entire piece more robustly, as it's such a central concept.

We have provided a short explanation of the challenge around the term noise and its subjectivity and this idea now appears twice in the text. This addition can be found in yellow highlight, at line 53

 

Line 18: "intrest" should be "interest". Also, the phrasing "no question about that" feels a little casual for a formal paper; maybe reword it slightly to maintain a more academic tone.

We cannot find either of these areas for edit that the reviewer has highlighted. Please provide more details if required.

 

Line 39: The keyword "environment" is listed; perhaps "sound environment" or "acoustic environment" would be more specific and helpful for indexing.

We feel there is a little confusion here. We do not have a keyword that is just “environment”. We already have a keyword that is “sound environment”.

 

Materials and Methods

The methodology for gathering stakeholder perspectives is generally sound, but I do have a few points about it. The relatively small number of delegates (12 from 20 invited) raises questions about the generalisability of the findings, even for a qualitative study; perhaps a more detailed explanation of why these specific individuals were chosen, beyond their expertise, could be useful. It's also worth noting the workshop was in March 2020 – just as the world was getting a bit chaotic – though the authors mention "untoward circumstances," it might be worth a small reflection on any potential wider impact on participant focus, if any was observed. Regarding the data analysis, the process for summarising key terms and phrases (lines 137-142) relies heavily on subjective interpretation, which is fine for qualitative work, but a more explicit statement on how inter-rater reliability was ensured or disagreements resolved could add rigor. Finally, the decision to group several diverse taxa (reptiles/amphibians and fish/invertebrates) due to "budgetary and logistical constraints" (lines 160-162) is completely understandable but is a pretty significant methodological limitation that should be emphasised more prominently in the discussion.

Thank you for the comments. We have included a statement saying that the UK was not in a Covid lockdown at the time of the workshop and the implications of the pandemic were not yet clear to participants. We do not believe their concentration on workshop tasks was significantly affected. This addition can be found in yellow highlight, line 130 to end of paragraph. We have added further details as to why we selected the original 20 people for invitation to attend, noting that we wished to include a range of stakeholders and invested parties in UK zoos and aquariums. This addition can be found in yellow highlight, lines 113-115.

We would clarify that we have not performed any inferential analyses, but have explained the procedure behind our analysis in more detail in the revised text (lines 146-155).

Furthermore, we have noted the small sample as a cause for extension and follow up by others in the discussion to acknowledge the specific nature of our outputs. Please see this in the appropriate area of the discussion in yellow highlight, within lines 454-4463 and 470-474.

Finally, we appreciate the reviewer’s comment on grouping of some taxa but we have already been open and honest clearly in the methods, stating that this is an area for future improvement. We have provided further evaluation of improvements to this in the discussion as above (please see the extended sections of the discussion, in yellow highlight, starting line 444).

 

Line 112: "veterinary surgeon" could just be "veterinarian" for conciseness, though "veterinary surgeon" isn't wrong.

Thank you for the comment however, we will keep “veterinary surgeon”.

 

Line 138: "main investigator" is used. It might be better to consistently refer to the specific author (e.g., "the first author" or "Dr. Rose") to avoid ambiguity.

We have edited section this for clarity. Please see the yellow highlighted section Where this has been re-written.

 

Line 142: "further inferential analysis was attempted" – "was attempted" feels a bit passive. "no further inferential analysis was conducted" might flow a bit better.

Edited. Please see yellow highlight.

 

Line 161: "untoward circumstances" is a very polite way to put it, and accurate for March 2020! Just make sure that's the intended level of formality.

Thank you. This is at line 129, but we have now changed the wording.

 

Line 189: "Web of Science database (webofscience.com)" - The URL doesn't really need to be there. Just "Web of Science database" is sufficient.

Thank you for the comment, however we disagree because there can be confusion between what the Web of Science platform is – if you put Web of Science into a Google search, you get multiple options. We keep this URL in the text in the spirit of open science and replication.

 

Results

The results section provides a wealth of information from the workshop, which is great. The tables (Tables 1, 2, 3) are quite informative, though sometimes the formatting makes them a bit dense; maybe breaking down some of the longer bullet points or using slightly more concise language could improve readability. My main comment here, however, concerns the word clouds (Figures 1 and 2). While they offer a nice visual summary, the statement that they were "generated with assistance from ChatGPT (OpenAI, 2025)" is a bit jarring for a scientific publication. It would be better to describe the process by which the word clouds were created (e.g., using specific text analysis software to identify frequent terms) rather than attributing it to an AI model, especially a recent one, as some readers might question the analytical independence or methodological robustness.

Tables 1-3 have been removed to Supplementary Information, and replaced with a description, following the comments of another reviewer. We have edited the captions on the word clouds as per the suggestion provided further on down.

 

Table 1: Some of the entries under "Do consider sound" are a little vague (e.g., "Hard to think of what is done" or "unsure of its biological relevance"). While these are direct quotes from delegates, maybe adding a small parenthetical note to clarify that these reflect the reported lack of existing practice rather than an authorial statement would be useful for the reader.

Thank you for the suggestion. This table is now in the Supplementary Information and a description of outputs is provided in the results. We have edited the table title according to the suggestion.

 

Table 2: "Taxonomic order" as a heading for the first column is a bit off, since it lists groups like "Birds" and "Mammals" rather than strict taxonomic orders. "Taxonomic Group" would be more accurate.

Thank you for the correction. We have edited this table (now supplementary) heading accordingly. Please see yellow highlight.

 

Line 207: "Table 1 presents responses from workshop delegates summarising where sound is currently considered..." - This sentence is a bit long. Consider breaking it up or rephrasing for improved flow.

Thank you for the feedback. This has since been edited based on feedback from the other reviewer.

 

Lines 335 and 339: The reference to "ChatGPT (OpenAI, 2025)" for word cloud generation might be better rephrased. For example, you could state "Word clouds were generated using text analysis software (e.g., [Software Name if applicable]) to identify frequent terms." This maintains academic rigor and avoids potential distraction for some readers.

Thank you for the suggested edit. We have re-written these figure captions accordingly. Please see yellow highlight in the caption under each figure.

 

Discussion

The discussion does a commendable job of linking the workshop outputs with existing literature and exploring the nuances of sound perception and management in zoos. I found the section on the definition of "noise" (lines 403-417) particularly insightful and well-articulated. The conclusions drawn are largely consistent with the evidence presented from the workshop discussions and the brief literature review. The paper addresses the main question posed by clearly outlining the current state of stakeholder awareness and practice regarding zoo sound environments. However, the limitations stemming from the small sample size and the necessary grouping of taxa in the workshop should be more explicitly discussed here, perhaps with a paragraph dedicated to how these factors might influence the breadth and generalizability of the findings. This would strengthen the paper's overall scientific argument.

Thank you for the feedback here. We have edited a fair amount of the discussion in response to all reviewer feedback, so we hope that these edits answer your concerns. All edited sections are highlighted in yellow.

 

Line 370: "ecotherms" should be "ectotherms." A small typo there.

Edited. Thank you for the correction.

 

Line 391: "four animals for example)" seems to have a stray parenthesis. Should probably be "four animals (for example) in the same enclosure..." or similar.

Edited. Thank you for spotting this.

 

Line 403: The use of quotes around "noise" (e.g., "what we mean by “noise”?") is good for emphasis, but ensure consistency throughout the paragraph; sometimes it's quoted, sometimes not.

Thank you for the feedback, we have checked this accordingly.

 

Line 443: "refuted with empirical evidence from research at the zoo" - maybe "supported or nuanced by empirical evidence" rather than "refuted," as 'refuted' can sound quite strong.

Edited accordingly.

 

Conclusions

The conclusions effectively summarise the key findings and their broader implications. They align well with the evidence, advocating for formal integration of sound into welfare planning, which is a strong take-home message. I think the final paragraph could perhaps reiterate even more strongly how the stakeholder perspective itself is a unique contribution, reinforcing why this approach was so valuable.

Line 470: "those for reptiles, amphibians, fish and invertebrates" might read slightly better as "particularly for reptiles, amphibians, fish, and invertebrates."

Thank you for the suggestion. We have edited this sentence and added text which we hope strengthens the case for our focus on stakeholder perspectives.

 

To enhance the paper's broader applicability, I recommend citing the recently published review by El-Sabrout et al. (2024), "Environmental Enrichment in Rabbit Husbandry: Comparative Impacts on Performance and Welfare," in the Conclusions section, specifically around lines 481-485. This manuscript provides an excellent example from another managed animal industry—rabbit farming—where the control of environmental stimuli is paramount for animal welfare. Including this reference would effectively strengthen the argument that the principles of managing sensory environments, though discussed here in a zoo context, have widespread relevance across diverse animal care settings, thus reinforcing the paper's overarching message about the importance of holistic and evidence-informed approaches.

Thank you for the feedback. We have included this example and its application into the discussion. Please see the yellow highlight, lines 597-603.

 

References

The references appear appropriate and cover a good range of relevant literature. I've noted a few recent publications, which is excellent. I didn't spot any major omissions or inconsistencies in the citation style, though a thorough check for uniform formatting would always be prudent during final edits.

Thank you for the comments on the reference list. We have attempted to use the correction referencing format for the journal but any inconsistencies should be picked up during processing for final publication.

 

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors have sufficiently addressed my concerns and I am happy to recommend this paper for publication.

Author Response

We thank the reviewer for their comments and help with paper development. We appreciate the time taken to help up improve our article.

Reviewer 3 Report

Comments and Suggestions for Authors

I've gone through the authors' replies and the changes they've made, and overall, I'm really pleased. I think they've done a great job of addressing the main points I raised.

Summary of the Revisions

First off, they've done a solid job with the bigger picture stuff. They've added a more nuanced explanation of what they mean by "noise" early on in the introduction, which I think really helps set the stage. They've also been very transparent about the methodological limitations, like the small sample size and the necessary grouping of taxa. They added more detail about their delegate selection process and even reflected on the timing of the workshop in March 2020, which shows a lot of rigor.

I also really appreciate that they've updated the captions for the word clouds to remove the reference to ChatGPT. I think that was a great call—it maintains the academic tone and avoids any potential questions about methodological independence. They've also moved the tables to the supplementary information and corrected the heading in Table 2 from "Taxonomic order" to "Taxonomic Group", which is a more accurate description.

Finally, they took my suggestion to include the El-Sabrout et al. (2024) paper, which I think is a fantastic addition. It really strengthens the argument by showing that the principles of managing sensory environments have widespread relevance beyond just zoos.

Further Minor Comments

Overall, the paper is in a much better place, but I did notice a few tiny things while reading through the responses. These are super minor and just a matter of polishing.

• Line 39, Keywords: The authors stated that "environment" isn't a keyword, but in my original comment, I was referring to the keywords list itself. Maybe there was a misunderstanding? I just wanted to make sure they checked that the list is clear and specific, which it sounds like it is now with "sound environment".
• Line 138, "main investigator": They said they edited this section for clarity, which is great. I'd just recommend they ensure the revised wording is specific and consistent. For instance, referring to "the first author" or by name avoids any ambiguity.
• Word Cloud Figures: The new captions are excellent. It would be a good idea to just make sure the process described for creating the word clouds is also briefly mentioned in the methods section, just to be fully transparent.

 

Author Response

Summary of the Revisions

First off, they've done a solid job with the bigger picture stuff. They've added a more nuanced explanation of what they mean by "noise" early on in the introduction, which I think really helps set the stage. They've also been very transparent about the methodological limitations, like the small sample size and the necessary grouping of taxa. They added more detail about their delegate selection process and even reflected on the timing of the workshop in March 2020, which shows a lot of rigor.

Thank you for the feedback. We really appreciate the positive comments and we are pleased that the revisions improve the clarity and relevance of the paper.

I also really appreciate that they've updated the captions for the word clouds to remove the reference to ChatGPT. I think that was a great call—it maintains the academic tone and avoids any potential questions about methodological independence. They've also moved the tables to the supplementary information and corrected the heading in Table 2 from "Taxonomic order" to "Taxonomic Group", which is a more accurate description.

Thank you for the feedback, and for the very upbeat and helpful review. It is nice to receive a review written in such positive and friendly tones.

Finally, they took my suggestion to include the El-Sabrout et al. (2024) paper, which I think is a fantastic addition. It really strengthens the argument by showing that the principles of managing sensory environments have widespread relevance beyond just zoos.

Thank you for the helpful addition of this example.

Further Minor Comments

Overall, the paper is in a much better place, but I did notice a few tiny things while reading through the responses. These are super minor and just a matter of polishing.

• Line 39, Keywords: The authors stated that "environment" isn't a keyword, but in my original comment, I was referring to the keywords list itself. Maybe there was a misunderstanding? I just wanted to make sure they checked that the list is clear and specific, which it sounds like it is now with "sound environment".

We apologise for any confusion here. We checked that "sound environment" was included as a keyword and it is.

• Line 138, "main investigator": They said they edited this section for clarity, which is great. I'd just recommend they ensure the revised wording is specific and consistent. For instance, referring to "the first author" or by name avoids any ambiguity.

Thank you for the comment. We have added to this section to improve the expression of information here. Hopefully this removes ambiguity. 

• Word Cloud Figures: The new captions are excellent. It would be a good idea to just make sure the process described for creating the word clouds is also briefly mentioned in the methods section, just to be fully transparent.

Thank you for the feedback. We have added this into lines 148-153 of the methods, in yellow highlight.