Beaked whales and state-dependent decision-making: how does body condition affect the trade-off between foraging and predator avoidance?

Body condition is central to how animals balance foraging with predator avoidance—a trade-off that fundamentally affects animal fitness. Animals in poor condition may accept greater predation risk to satisfy current foraging ‘needs’, while those in good condition may be more risk averse to protect future ‘assets’. These state-dependent behavioural predictions can help interpret responses to human activities, but are little explored in marine animals. This study investigates the influence of body condition on how beaked whales trade-off foraging and predator avoidance. Body density (indicating lipid-energy stores) was estimated for 15 foraging northern bottlenose whales tagged near Jan Mayen, Norway. Composite indices of foraging (diving and echolocation clicks) and anti-predation (long ascents, non-foraging dives and silent periods reducing predator eavesdropping) were negatively related. Experimental sonar exposures led to decreased foraging and increased risk aversion, confirming a foraging/perceived safety trade-off. However, lower lipid stores were not related to a decrease in predator avoidance versus foraging, i.e. worse condition animals did not prioritize foraging. Individual differences (personalities) or reproductive context could offer alternative explanations for the observed state-behaviour relationships. This study provides evidence of foraging/predator-avoidance trade-offs in a marine top predator and demonstrates that animals in worse condition might not always take more risks.


Do you have any concerns about statistical analyses in this paper? If so, please specify them explicitly in your report. No
It is a condition of publication that authors make their supporting data, code and materials available -either as supplementary material or hosted in an external repository. Please rate, if applicable, the supporting data on the following criteria.

Do you have any ethical concerns with this paper? No
Comments to the Author I found this to be an extremely well written paper on an interesting topic. The introduction was strongly rooted in theory, and beaked whales provide an interesting case study for answering questions about state-dependence given the relative ease of calculating foraging and predatoravoidance behaviors as well as body condition. The statistical analysis was generally strong, and the authors were creative in their use of anti-predator and foraging metrics. However, I struggled with the interpretation of the main data figure (specifically, the leverage that one datapoint has on the model fit and thus interpretation and implications of the paper). I am concerned that given the cross-sectional rather than longitudinal approach, and the strong impact of a single datapoint that could easily have been affected by personality or habituation, question the strong statements underlying the pitch of the paper. As a result, I feel that the language needs to be softened throughout the paper, and that the manuscript may be better suited to a slightly lower tiered journal.
Major comments • L26-28 suggests that skinnier animals minimized predation risk… But this is a chickenor-egg question (what came first?). What if body condition was low because animals used more anti-predator behaviors at the expense of foraging? I don't think this necessarily suggests that the needs/assets hypothesis is not true. • When the one animal was excluded, CLAP/CLF did not vary with body density -so statements in the abstract should be softened. Figure 1b should not have a line because it is not significant. L25-28 is not supported by the data. Without this result, the novelty of the manuscript is somewhat reduced (because, for example Figure 1A -the negative relationship between foraging and anti-predator behaviors -are an emergent property, as discussed in L310). Also, this should not be interpreted as strong negative support for the needs/assets hypothesis, as is written into several sections of the paper (e.g., L284-286). • Much of this work, especially the discussion, is pitched as the starvation-predation tradeoff. While I appreciate this effort, I think the tradeoff being measured here is foraging versus predator avoidance. The authors could add a few sentences to discuss this difference. For example, what are the body density values in this species that might lead to starvation? Minor comments Abstract: In abstract, response to sonar exposure is termed predator avoidance… should this be considered risk aversion? Threat avoidance? I agree it is analogous, but I do not think that behavioral changes from sonar exposure should be called predator avoidance. I appreciate the nuanced discussion section (e.g., L330-334) and would like to see more careful wording in the abstract. L13: Start to abstract is dry L18: grammar L20: Where foraged, not tagged L21: Is acoustic crypsis an anti-prey behavior as well? L25: Simplify to lower lipid stores (remove higher body density) L30: Abstract concluding sentence should broaden out results / discuss implications rather than justify why a certain result was not found L65: The safety component of this should be underscored. Suggest changing to "rested more during the safety of nighttime and at deeper depths…" L75: Suggest giving an example of anthropogenic disturbances that are concerning. Sonar? L86: Change "this study" to "we" L88: Suggest removing "of this marine top predator" L90: It was unclear to me in the abstract whether sonar was experimentally added or whether it was naturally encountered. Here it is clear that experimental exposures were done -please add this to the abstract. L124: Change grammar to "During stable five-second glide segments, measurements (acceleration…)" L139: What is the unit for buzz rate? L148: What constitutes "regular clicks"? Is this objective or subjective? L149: Change to "long bottom phase durations" L151: I found this paragraph relatively hard to follow. Perhaps a figure would help (i.e., convert the table to a figure with more helpful information). L234: I would like to see statistical analysis in this section. Are these comparisons biologically or statistically relevant? For example, the percentage of time being non-vocal near the surface increased from 97.3 to 100%, which is a very minor change. L213: Is there precedent for using dominant stroke frequency as an index of body size? I see in L218-219 that this is repeated, with citations, and now understand that L213 is meant to be an overview of the paragraph. I suggest removing "(an index of body size") in L213 to resolve this confusion. L258: I don't believe it is necessary to specify that delta AICc is 0 here -this is clearly the best fitting model. Fig 2: This is somewhat unclear to me -are 2013, 2015, and 2016 the three individual whales, or years, or both? Also, it would be helpful if the foraging metrics (presumably A,B,C) are somehow differentiated from the other metrics. For this figure and the others, it would be helpful to have more information about how many dives are represented. L290: Replace "predicted" with "was related to" L352: Replace "which annually cycle their lipid stores" with something like "which experience vast differences in lipid stores across seasons" L377: This paragraph epitomizes my struggle with the inclusion of individual O in the regression. Because this study is cross-sectional rather than longitudinal, it seems that one whale with high (low) body condition could have simply been less of a risk taker, and has strong leverage on the linear model fit.

Quality of the paper: Is the overall quality of the paper suitable? Excellent
Is the length of the paper justified? Yes Should the paper be seen by a specialist statistical reviewer? No Do you have any concerns about statistical analyses in this paper? If so, please specify them explicitly in your report. No It is a condition of publication that authors make their supporting data, code and materials available -either as supplementary material or hosted in an external repository. Please rate, if applicable, the supporting data on the following criteria.

Do you have any ethical concerns with this paper? No
Comments to the Author This is a well-written paper that has taken a creative approach to address the needs/assets hypothesis. This is an important concept in foraging theory but rarely addressed in marine systems. The authors set up the paper clearly in the intro and outline how they are going to address this in beaked whales. A strength of this study is how the authors first address the tradeoffs between predator avoidance and foraging behavior. Next they test the hypotheses that antipredator behavior will increase and foraging decrease when exposed to a stressor. After clearly establishing this trade off, they test the hypothesis that animals in lower body condition will forage more as predicted from the needs/assets hypotheses. The data does not support this hypothesis, but the authors provide possible explanations including a low risk life-history strategy for this species, to low variation in body condition in the 15 individuals studied, to personality impacts. My main comment is that the paper would be improved if more information on the playbacks are included in the methods. Without carefully examining the supplemental tables it was unclear if the 3 playback animals were included in the 15. Since they are, I would make this clear in the methods and then explain how you only used the baseline data when looking at the relationship between body condition and AP/Foraging relationship (at least that is what I think you did, based on the supplemental table -if you did not do this, then you should). Overall, the methods are well-explained and appropriate. I like how the models tested are included in the supplemental material. Minor comments: Line 73-77: Small style recommendation -the transition between these two sentences is abrupt. Writing would be stronger if connect ideas more clearly Table 2: check your r value for % foraging dive vs ascent depth. The r listed is 0, yet you say this is significant. Fig 1: One way to make it clear in the paper that some of the individuals were exposed to sonar would be to bold those individuals in Fig 1. But if you only analyze baseline data then this is not essential (but you still need to explain this in the methods). If figure 1b some of the letters have lines through them. I am assuming this is a mistake -maybe a conversion error. If not, then you need to explain why.

06-Jul-2021
Dear Ms Siegal: I am writing to inform you that your manuscript RSPB-2021-1160 entitled "Beaked whales and state-dependent decision-making: how does body condition affect the starvation-predation tradeoff?" has, in its current form, been rejected for publication in Proceedings B.
This action has been taken on the advice of referees, who have recommended that substantial revisions are necessary. With this in mind we would be happy to consider a resubmission, provided the comments of the referees are fully addressed. However please note that this is not a provisional acceptance.
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Please find below the comments made by the referees, not including confidential reports to the Editor, which I hope you will find useful. If you do choose to resubmit your manuscript, please upload the following: 1) A 'response to referees' document including details of how you have responded to the comments, and the adjustments you have made. 2) A clean copy of the manuscript and one with 'tracked changes' indicating your 'response to referees' comments document.
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Sincerely, Dr Daniel Costa mailto: proceedingsb@royalsociety.org Associate Editor Board Member: 1 Comments to Author: Both myself and the reviewers thought the manuscript was well written and used a creative approach to address the needs/assets hypothesis that is rarely addressed in marine systems. Both reviewers felt the study system was well chosen and appreciated the metrics of foraging and predator avoidance behaviors and the fairly unique ability to assess body condition in a freeranging marine predator based on the considerable previous work done by the authors in this area. The second reviewer raised some relatively minor issues about the methods and results presentation. However, one reviewer has raised some important concerns about the results interpretation, the strength of the conclusion drawn and the influence of one outlier data point on the conclusions drawn as written . I agree with the reviewer that this issue potentially effects the suitability of the paper for Proc B and requires response or revison from the authors.
Reviewer(s)' Comments to Author: Referee: 1 Comments to the Author(s) I found this to be an extremely well written paper on an interesting topic. The introduction was strongly rooted in theory, and beaked whales provide an interesting case study for answering questions about state-dependence given the relative ease of calculating foraging and predatoravoidance behaviors as well as body condition. The statistical analysis was generally strong, and the authors were creative in their use of anti-predator and foraging metrics. However, I struggled with the interpretation of the main data figure (specifically, the leverage that one datapoint has on the model fit and thus interpretation and implications of the paper). I am concerned that given the cross-sectional rather than longitudinal approach, and the strong impact of a single datapoint that could easily have been affected by personality or habituation, question the strong statements underlying the pitch of the paper. As a result, I feel that the language needs to be softened throughout the paper, and that the manuscript may be better suited to a slightly lower tiered journal. Major comments • L26-28 suggests that skinnier animals minimized predation risk… But this is a chicken-or-egg question (what came first?). What if body condition was low because animals used more antipredator behaviors at the expense of foraging? I don't think this necessarily suggests that the needs/assets hypothesis is not true. • When the one animal was excluded, CLAP/CLF did not vary with body density -so statements in the abstract should be softened. Figure 1b should not have a line because it is not significant. L25-28 is not supported by the data. Without this result, the novelty of the manuscript is somewhat reduced (because, for example Figure 1A -the negative relationship between foraging and anti-predator behaviors -are an emergent property, as discussed in L310). Also, this should not be interpreted as strong negative support for the needs/assets hypothesis, as is written into several sections of the paper (e.g., L284-286). • Much of this work, especially the discussion, is pitched as the starvation-predation trade-off. While I appreciate this effort, I think the tradeoff being measured here is foraging versus predator avoidance. The authors could add a few sentences to discuss this difference. For example, what are the body density values in this species that might lead to starvation? Minor comments Abstract: In abstract, response to sonar exposure is termed predator avoidance… should this be considered risk aversion? Threat avoidance? I agree it is analogous, but I do not think that behavioral changes from sonar exposure should be called predator avoidance. I appreciate the nuanced discussion section (e.g., L330-334) and would like to see more careful wording in the abstract. L13: Start to abstract is dry L18: grammar L20: Where foraged, not tagged L21: Is acoustic crypsis an anti-prey behavior as well? L25: Simplify to lower lipid stores (remove higher body density) L30: Abstract concluding sentence should broaden out results / discuss implications rather than justify why a certain result was not found L65: The safety component of this should be underscored. Suggest changing to "rested more during the safety of nighttime and at deeper depths…" L75: Suggest giving an example of anthropogenic disturbances that are concerning. Sonar? L86: Change "this study" to "we" L88: Suggest removing "of this marine top predator" L90: It was unclear to me in the abstract whether sonar was experimentally added or whether it was naturally encountered. Here it is clear that experimental exposures were done -please add this to the abstract. L124: Change grammar to "During stable five-second glide segments, measurements (acceleration…)" L139: What is the unit for buzz rate? L148: What constitutes "regular clicks"? Is this objective or subjective? L149: Change to "long bottom phase durations" L151: I found this paragraph relatively hard to follow. Perhaps a figure would help (i.e., convert the table to a figure with more helpful information). L234: I would like to see statistical analysis in this section. Are these comparisons biologically or statistically relevant? For example, the percentage of time being non-vocal near the surface increased from 97.3 to 100%, which is a very minor change. L213: Is there precedent for using dominant stroke frequency as an index of body size? I see in L218-219 that this is repeated, with citations, and now understand that L213 is meant to be an overview of the paragraph. I suggest removing "(an index of body size") in L213 to resolve this confusion. L258: I don't believe it is necessary to specify that delta AICc is 0 here -this is clearly the best fitting model. Fig 2: This is somewhat unclear to me -are 2013, 2015, and 2016 the three individual whales, or years, or both? Also, it would be helpful if the foraging metrics (presumably A,B,C) are somehow differentiated from the other metrics. For this figure and the others, it would be helpful to have more information about how many dives are represented. L290: Replace "predicted" with "was related to" L352: Replace "which annually cycle their lipid stores" with something like "which experience vast differences in lipid stores across seasons" L377: This paragraph epitomizes my struggle with the inclusion of individual O in the regression. Because this study is cross-sectional rather than longitudinal, it seems that one whale with high (low) body condition could have simply been less of a risk taker, and has strong leverage on the linear model fit.
Referee: 2 Comments to the Author(s) This is a well-written paper that has taken a creative approach to address the needs/assets hypothesis. This is an important concept in foraging theory but rarely addressed in marine systems. The authors set up the paper clearly in the intro and outline how they are going to address this in beaked whales. A strength of this study is how the authors first address the tradeoffs between predator avoidance and foraging behavior. Next they test the hypotheses that antipredator behavior will increase and foraging decrease when exposed to a stressor. After clearly establishing this trade off, they test the hypothesis that animals in lower body condition will forage more as predicted from the needs/assets hypotheses. The data does not support this hypothesis, but the authors provide possible explanations including a low risk life-history strategy for this species, to low variation in body condition in the 15 individuals studied, to personality impacts. My main comment is that the paper would be improved if more information on the playbacks are included in the methods. Without carefully examining the supplemental tables it was unclear if the 3 playback animals were included in the 15. Since they are, I would make this clear in the methods and then explain how you only used the baseline data when looking at the relationship between body condition and AP/Foraging relationship (at least that is what I think you did, based on the supplemental table -if you did not do this, then you should). Overall, the methods are well-explained and appropriate. I like how the models tested are included in the supplemental material. Minor comments: Line 73-77: Small style recommendation -the transition between these two sentences is abrupt. Writing would be stronger if connect ideas more clearly Table 2: check your r value for % foraging dive vs ascent depth. The r listed is 0, yet you say this is significant. Fig 1: One way to make it clear in the paper that some of the individuals were exposed to sonar would be to bold those individuals in Fig 1. But if you only analyze baseline data then this is not essential (but you still need to explain this in the methods). If figure 1b some of the letters have lines through them. I am assuming this is a mistake -maybe a conversion error. If not, then you need to explain why. It is a condition of publication that authors make their supporting data, code and materials available -either as supplementary material or hosted in an external repository. Please rate, if applicable, the supporting data on the following criteria.

Do you have any ethical concerns with this paper? No
Comments to the Author Thank you for your thorough responses; the manuscript has been greatly improved, and I am happy with its publication.

10-Dec-2021
Dear Dr Siegal I am pleased to inform you that your manuscript RSPB-2021-2539 entitled "Beaked whales and state-dependent decision-making: how does body condition affect the trade-off between foraging and predator avoidance?" has been accepted for publication in Proceedings B.
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Sincerely, Dr Daniel Costa mailto: proceedingsb@royalsociety.org Reviewer(s)' Comments to Author: Referee: 1 Comments to the Author(s). Thank you for your thorough responses; the manuscript has been greatly improved, and I am happy with its publication.

20-Dec-2021
Dear Dr Siegal I am pleased to inform you that your manuscript entitled "Beaked whales and state-dependent decision-making: how does body condition affect the trade-off between foraging and predator avoidance?" has been accepted for publication in Proceedings B.
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Re: Resubmission of RSPB-2021-1160
Dear Professor Costa, Thank you very much for inviting us to resubmit our manuscript (RSPB-2021(RSPB- -1160 to the Proceedings of the Royal Society B. We would also like to thank both anonymous reviewers for their highly constructive feedback. Please see the corresponding response documents for how we have addressed their comments, which have considerably improved the manuscript. Reviewer 1's primary concern was regarding the interpretation of the main data figure, in particular the strong impact of one datapoint and the cross-sectional nature of our study. We agree that the cross-sectional approach means that the statistically significant positive result could be due to the particularities of the individual whales sampled (via tagging), and that the single influential datapoint may have been affected by other factors (e.g., personality or immediate factors such as sensitisation to prior sonar exposure), so it is fair to question the generalisability of that result. We have therefore reduced emphasis on the positive correlation found in Figure 1b.
However, while we agree that it is not justified to argue that the unexpected positive relationship between body density and CIAP/CIF can be generalized beyond our study, it is clear that our study did not support the expected negative relationship between body density and CIAP/CIF as a priori predicted from the needs/assets hypothesis. This finding remains an important and key result, indicating that individuals in worse condition might not increase foraging and individuals in better condition might not increase avoidance behaviour as expected. This finding, in addition to our study establishing effective foraging and anti-predator indicators in a beaked whale, which were modified as expected by experimental exposure to sonar, will be of broad general interest to animal biologists. We therefore hope you will find the revised manuscript acceptable for Proc Roy Soc B.
We have provided a 'clean' word document and a word document with changes tracked from the previously submitted version.
We look forward to hearing from you.
Sincerely, Eilidh Siegal, on behalf of all co-authors Appendix A

Comment number
Reviewer 1 -major comments Response 1 I found this to be an extremely well written paper on an interesting topic. The introduction was strongly rooted in theory, and beaked whales provide an interesting case study for answering questions about state-dependence given the relative ease of calculating foraging and predator-avoidance behaviors as well as body condition. The statistical analysis was generally strong, and the authors were creative in their use of anti-predator and foraging metrics.
Thank you very much for your review of our manuscript and for providing positive, constructive and useful feedback. We really appreciate your thorough reading and detailed comments, which have helped improve the manuscript and are addressed in the table below.
2 However, I struggled with the interpretation of the main data figure (specifically, the leverage that one datapoint has on the model fit and thus interpretation and implications of the paper). I am concerned that given the cross-sectional rather than longitudinal approach, and the strong impact of a single datapoint that could easily have been affected by personality or habituation, question the strong statements underlying the pitch of the paper. As a result, I feel that the language needs to be softened throughout the paper, and that the manuscript may be better suited to a slightly lower tiered journal.
We agree that the one datapoint had a good deal of leverage on the results. We have made this clear in the text and figure, and have modified the manuscript to not base our conclusions on this. In fact, the empirical lack of the predicted relationship between body density and CIAP/CIF remains a valuable result. Few studies have assessed foragingpredator avoidance trade-offs in marine top predators, and even fewer studies have looked at how these trade-offs could relate to body condition. As such, the empirical evidence in our study that a pattern expected by the needs/assets hypothesis did not occur provides novel insights into behavioural trade-offs and how these trade-offs might relate to body condition in a difficult-to-study marine animal, and thus this study (which uses non-invasive widely-applicable methods) still has general interest to animal biologists.
We have modified the language throughout the manuscript as suggested.
For example, instead of focussing on the positive line in Figure 1b, the text now focuses on the relationship between body condition and foraging-predator avoidance trade-offs not being that as predicted by the needs/assets hypothesis (i.e., the results clearly don't indicate a negative relationship) and the potential reasons for why this might be (e.g., body condition values were not extreme enough to drive increased risk-taking etc.).
The following are examples of where the language has been changed and softened: L26-28 suggests that skinnier animals minimized predation risk… But this is a chicken-or-egg question (what came first?). What if body condition was low because animals used more anti-predator behaviors at the expense of foraging? I don't think this necessarily suggests that the needs/assets hypothesis is not true.
We agree that this could be a chicken-or-egg question, which we had stressed in our discussion on how factors such as personality could lead to the observed data. The wording in the abstract has been amended accordingly [L30 -34], so as to not state that animals in worse condition minimised predation risk (or used more anti-predator behaviours at the expense of foraging). The wording instead now focusses on reflecting the result and consistency with comment #4 below.
We also agree that the relationship between body density and CIAP/CIF does not necessarily suggest the needs/assets hypothesis is not true and have addressed this (please see response to comment #4 for more detail).

4
When the one animal was excluded, CLAP/CLF did not vary with body density -so statements in the abstract should be softened. Figure 1b should not have a line because it is not significant. L25-28 is not supported by the data. Without this result, the novelty of the manuscript is somewhat reduced (because, for example Figure 1A -the negative relationship between foraging and anti-predator behaviors -are an emergent property, as discussed in L310). Also, this should not be interpreted as strong negative support for the needs/assets hypothesis, as is written into several sections of the paper (e.g., L284-286).
Thank you very much for this constructive feedback.
We have modified the language throughout the manuscript (please see response to comment #2).
We have not removed the model line from Figure 1b [L728] as the result is supported by the empirical data and there is no reason to doubt the validity of that datapoint. However, we have softened our interpretation of the generalizability of the surprising positive relationship as we agree that the cross-sectional nature of the study means that the statistically significant positive result could have been due to the particularities of which whales were sampled (via tagging) in our study. We have edited L25 -28 [now L30 -34] accordingly. We agree that the lack of relationship between body density and CIAP/CIF does not equate to there being strong negative support for the needs/assets hypothesis and appreciate that our wording on this was too strong. Figure 1b convincingly demonstrates a lack of the expected negative relationship between body density and CIAP/CIF as predicted from the needs/assets hypothesis (i.e., that animals in worse condition have higher levels of foraging).
We have modified the wording throughout (including L284-286, now L327-330), to state that the results are "unexpected" (rather than "opposite" or "contrary") from the predictions of the needs/assets hypothesis (but we note the lack of proof that the hypothesis is not true).

5
Much of this work, especially the discussion, is pitched as the starvationpredation trade-off. While I appreciate this effort, I think the tradeoff being measured here is foraging versus predator avoidance. The authors could add a few sentences to discuss this difference. For example, what are the body density values in this species that might lead to starvation?
Thank you for raising this point. We do not have a way to estimate what body density might relate to starvation in this species. However, we do agree with the reviewer, as indicated in the discussion that the predicted trade-off may operate at the extreme levels of body condition that reflect risk of starvation.
We therefore accept the point that "foraging versus predator avoidance" more accurately describes the trade-offs being measured, and have changed the wording throughout the manuscript to "foraging versus predator avoidance trade-off" (rather than "starvation-predation tradeoff"). We have included text describing the difference between the two (L47 -57).

Comment number
Reviewer 1 -minor comments Response 6 Abstract: In abstract, response to sonar exposure is termed predator avoidance… should this be considered risk aversion? Threat avoidance? I agree it is analogous, but I do not think that behavioral changes from sonar exposure should be called predator avoidance. I appreciate the nuanced discussion section (e.g., L330-334) and would like to see more careful wording in the abstract.
Thank you for highlighting this. We agree that behavioural changes to sonar shouldn't be termed "predator avoidance". The text has therefore been updated to "increased risk aversion" [L29]. This section [L272] provides support for our foraging and anti-predation indicators, in terms of expected changes with an increase in perceived risk. With only three tag deployments, we are not keen to attempt statistical analyses, but consider this section nevertheless valuable in showing consistency of response between the three individuals.

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L213: Is there precedent for using dominant stroke frequency as an index of body size? I see in L218-219 that this is repeated, with citations, and now understand that L213 is meant to be an overview of the paragraph. I suggest removing "(an index of body size") in L213 to resolve this confusion.
Yes, fundamental stroke frequency was originally related to body size across species [44] but has also been applied to proxy body size within a species (e.g., in pilot whales, Isojunno et al. 2018). Changed as suggested [L249].

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L258: I don't believe it is necessary to specify that delta AICc is 0 here -this is clearly the best fitting model.
We have deleted "(ΔAICc = 0, Akaike weight = 0.48)" accordingly in L296 -297. These values can also be found in Supplement 4, which is referenced in this sentence. 26 Fig 2: This is somewhat unclear to me -are 2013, 2015, and 2016 the three individual whales, or years, or both? Also, it would be helpful if the foraging metrics (presumably A,B,C) are somehow differentiated from the other metrics. For this figure and the others, it would be helpful to have more information about how many dives are represented.
We have edited Figure 2:  The previous labels of "2013", "2015" and "2016" represented three individual whales tagged in those years. These labels have now been changed to "a", "l" and "n" (the individual whale codes used in Figure 1 and Table S1).  The plot layout has been changed (previously arranged as a 3 X 3 matrix of subplots), so that the foraging indicators are on the top row, and anti-predator indicators are on the bottom row (and labelled accordingly on the outer Y axis).  For the three indicators (ascent-pitch-shallowness, ascent depth, and ascent-straightness index) that are calculated as mean values across mid-depth and long-deep dives, the number of dives is now represented as a label above the bar.
These changes have been explained in the Figure description [L743 -747]. 27 L290: Replace "predicted" with "was related to" Changed as suggested [L335] 28 L352: Replace "which annually cycle their lipid stores" with something like "which experience vast differences in lipid stores across seasons" Changed as suggested, replacing "which annually cycle their lipid stores" with "which, with seasonal migrations, experience vast differences in their lipid stores across seasons" [L410 -411] 29 L377: This paragraph epitomizes my struggle with the inclusion of individual O in the regression. Because this study is cross-sectional rather than longitudinal, it seems that one whale with high (low) body condition could have simply been less of a risk taker, and has strong leverage on the linear model fit.
The wording of this paragraph and the following paragraph [L444 -476] has been amended in-line with comments #2 and #4 above (wording softened, and discussion of the nature of this study being cross-sectional rather than longitudinal). We also consider that individual O could have simply been more of a risk taker.