Review Reports

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript presents results of a interesting dataset exploring the links between tree seed production and the temporal dynamics of a reasonably diverse guild of small mammals in two Mediterranean forest ecosystems.  The paper is well written and has lots of interesting (if largely empirical) results.

It has become common for authors to flag issues of “conservation and management of biodiversity in protected areas” as part of the motivation for studies such as this one.  I miss the days when the focus was more clearly on advancing our general understanding of ecological dynamics (and testing theoretical models).  The current study is an useful contribution to our understanding of the dynamics of tree seed production and the population dynamics of an important guild of seed predators in Mediterranean forests.  That is enough motivation for me.  That said, I would have appreciated more material in the Introduction and Discussion that linked the empirical results here with the very rich and more theoretical literature on seed production/seed predation.  In contrast, the paper wraps up with a fairly standard set of warnings that climate change (and afforestation) can be expected to change the dynamics of both the seed producers and the seed consumers.  That is reasonable.  It would be hard, however, to see those trends showing up in the results in Fig. 4.

I have to say that I was a bit concerned by the spatial disconnect between the small mammal trap sites and the sites were seed rain was measured.  In each of the two domains (beech vs. oak) some of the trapping sites look to be as much as 10 km away from the sites where seed rain was measured.  There is growing evidence that (1) the strength of regional synchrony in seed production is not as great as often assumed, and (2) the fraction of trees within a local population that actually produce viable seeds even in a mast year can vary quite a bit spatially.  As a result, even after controlling for the biomass/abundance of a tree species locally there can still be a lot of spatial variation in tree seed rain at a given location. 

So I tend to view the methods here as simply providing a fairly coarse temporal index of year-to-year variation in seed production (with the possibility that there was considerable variation among the trap sites in seed rain in any given year).  Figure 3 appears to bear this out.  While the text highlights “a certain interannual synchrony” in seed rain, I look at Figure 3 and see lots of spatial variation in both the oak and beech sites.  The oak sites, in particular, tend to deviate from the classical assumption that masting is strongly bimodal (all or nothing), since there are sites with intermediate seed crops between the two years with very high acorn production (2014 and 2017). 

As a result, I have no way of knowing whether the “relatively low explanatory power” (line 271) of the models might be due to the coarseness of the measure of local seed rain.

The interesting results with the response of the shrew echo results from a classic New Zealand study of Nothofagus and house mice in the Orongorongo Valley, where if I remember correctly the timing of the response of the mice to beech mast suggested that the mice were feeding on a pre-dispersal insect seed consumer.

Line 125:  I think you mean “seed fall”, not “tree falling”

Fig. 4:  the caption needs more detail – what specifically are the error bars on the shaded seed rain bars?

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This manuscript used a 10-year study in mixed Mediterranean oak-beech forests to understand the impacts of seed availability on small mammal populations. They found that wood mice have high sensitivity to both masting and non-masting years. Other mice with different life-history traits and diets show different responses. This manuscript is well written, and I think some revisions are needed.

First, there is a recent study that leverages a huge dataset from the Masting Inference and Forecasting (MASTIF) network that shows how traits of vertebrate consumers interact with the masting behavior of trees. I think the paper needs to be cited here. It is a global scale analysis and can support some of the conclusions in this paper.

Qiu, T., Aravena, MC., Ascoli, D. et al. Masting is uncommon in trees that depend on mutualist dispersers in the context of global climate and fertility gradients. Nat. Plants 9, 1044–1056 (2023). https://doi.org/10.1038/s41477-023-01446-5

Second, the paper did mention climate impacts in the introduction (L78-93) but omitted the impacts of nutrients. I think the introduction can benefit from how nutrients influence masting behavior and then small mammals.

Figure 2: it would be nice to have those sample locations on figure 1 so that reader can understand which eco-regions sample plots belong to.

Figure 3: are line plots using the mean values from points?

Discussion: I enjoyed reading this part. Great job!

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

I found this manuscript well written and interesting to read. The authors wrote a good Introduction and well-described methods, and good Desults and Discussion. However, there a few things that need to be changed or fixed to improve the language, enhance clarity, or correct errors as I comment below.  Please see below for detailed comments and suggestions. 

 

Abstract 

 

L15: does “rapid population responses” mean a rapid population increase?

 

Introduction 

 

L33: “take on” is not a scientific phrase, please replace with suitable terminology.

 

L40: “particularly important” instead of “particularly noteworthy.”

 

L41: seed dispersers or seed predators? Seed predators destroy the seed, not disperse it. Rodents can do both, so please fix this sentence to improve clarity.

 

L48: “movement” instead of “movements.”

 

L58: remove the comma before “is”

 

L73: “This will increase the frequency and intensity of dry spells characteristic of this climiate, which in turn will increase the soil aridity.” instead of the current sentence.

 

L76: “shift towards” instead of “shift to”

 

LL78-80: You need to cite a reference or references to support this. 

 

L83: Do you mean synchronous and asynchronous seed production here?

 

L86: What do you mean by “present the acorn maturating process”?

 

L99: “The interplay between these factors …” instead of “The interplay of these factors …”

 

L100: “small mammal species” instead of “small mammals’ species”

 

L102: “influence the population dynamics of small mammals …” instead of the current. 

 

L104: “, such as” instead of “as”

 

L110: “The main objective was …” instead of the current. 

 

L111: “in response to seed availability in mixed oak …” instead of the current.

 

L121-131: should be in past tense. Also, this section is written mostly in complex sentence. Better to break these up in simple and clear sentences. 

 

Methods

 

L145: “1712 m” instead of “1.712 m” or something else?

 

L199: “intact” instead of “sound”

 

LL200-207: “quadrats” instead of “squares”

 

Results

 

LL246-250: You should include all the stats in this section, not only the p-values.

 

LL251-256: does X mean the mean seed production value? if yes, better to use “mean” instead. Also, include all the stats in this section, especially if there is a significant difference between the two genera. If not, you need to state that. 

Discussion 

 

L302: “exhibited” instead of “exhibit”

 

LL302-303: seed availability or seed production?

 

L314: “revealed distinct patterns in responding to seasonality and …” instead of the current. 

 

L315: seed producers you mean? “tree producers” does not make sense. Perhaps ‘tree species’ could be used here. 

 

L322: “exhibits” instead of “presents”

 

LL328-331: you need to cite those former studies here. 

 

L338: “saw-tooth pattern” is not scientific. Better to replace this with a more scientific term. Perhaps “boom and bust dynamics”?

 

L387: I do not understand what “tress hold invertebrates” mean here. Does it mean harbor or host?

 

LL412-414: you need to cite a relevant reference here.

 

L434: “a cascade of effects” instead of “a cascade of interactions”

 

L444: remove “solid”

 

Figures

 

Figure 3. Better to add x- and y-axes to the figure. Also, you need to add the unit to the y-axis (Number of seeds). 

L258: “Seed availability per year for the main tree species” Instead of the current figure legend. 

 

Figure 4. Better to add x- and y-axes to the figure. Also, you need to add the unit to the y-axes.

The figures also need to show the significant differences or lack thereof in the bar plots. 

 

Tables

 

Tables are OK. 

 

 

Comments on the Quality of English Language

Comments on the language are included in the detailed report above. 

I found this manuscript well written and interesting to read. The authors wrote a good Introduction and well-described methods, and good Desults and Discussion. However, there a few things that need to be changed or fixed to improve the language, enhance clarity, or correct errors as I comment below. After those changes and edits have been made, the manuscript can be accepted for publication. Please see below for detailed comments and suggestions. 

 

Abstract 

 

L15: does “rapid population responses” mean a rapid population increase?

 

Introduction 

 

L33: “take on” is not a scientific phrase, please replace with suitable terminology.

 

L40: “particularly important” instead of “particularly noteworthy.”

 

L41: seed dispersers or seed predators? Seed predators destroy the seed, not disperse it. Rodents can do both, so please fix this sentence to improve clarity.

 

L48: “movement” instead of “movements.”

 

L58: remove the comma before “is”

 

L73: “This will increase the frequency and intensity of dry spells characteristic of this climiate, which in turn will increase the soil aridity.” instead of the current sentence.

 

L76: “shift towards” instead of “shift to”

 

LL78-80: You need to cite a reference or references to support this. 

 

L83: Do you mean synchronous and asynchronous seed production here?

 

L86: What do you mean by “present the acorn maturating process”?

 

L99: “The interplay between these factors …” instead of “The interplay of these factors …”

 

L100: “small mammal species” instead of “small mammals’ species”

 

L102: “influence the population dynamics of small mammals …” instead of the current. 

 

L104: “, such as” instead of “as”

 

L110: “The main objective was …” instead of the current. 

 

L111: “in response to seed availability in mixed oak …” instead of the current.

 

L121-131: should be in past tense. Also, this section is written mostly in complex sentence. Better to break these up in simple and clear sentences. 

 

Methods

 

L145: “1712 m” instead of “1.712 m” or something else?

 

L199: “intact” instead of “sound”

 

LL200-207: “quadrats” instead of “squares”

 

Results

 

LL246-250: You should include all the stats in this section, not only the p-values.

 

LL251-256: does X mean the mean seed production value? if yes, better to use “mean” instead. Also, include all the stats in this section, especially if there is a significant difference between the two genera. If not, you need to state that. 

Discussion 

 

L302: “exhibited” instead of “exhibit”

 

LL302-303: seed availability or seed production?

 

L314: “revealed distinct patterns in responding to seasonality and …” instead of the current. 

 

L315: seed producers you mean? “tree producers” does not make sense. Perhaps ‘tree species’ could be used here. 

 

L322: “exhibits” instead of “presents”

 

LL328-331: you need to cite those former studies here. 

 

L338: “saw-tooth pattern” is not scientific. Better to replace this with a more scientific term. Perhaps “boom and bust dynamics”?

 

L387: I do not understand what “tress hold invertebrates” mean here. Does it mean harbor or host?

 

LL412-414: you need to cite a relevant reference here.

 

L434: “a cascade of effects” instead of “a cascade of interactions”

 

L444: remove “solid”

 

Figures

 

Figure 3. Better to add x- and y-axes to the figure. Also, you need to add the unit to the y-axis (Number of seeds). 

L258: “Seed availability per year for the main tree species” Instead of the current figure legend. 

 

Figure 4. Better to add x- and y-axes to the figure. Also, you need to add the unit to the y-axes.

The figures also need to show the significant differences or lack thereof in the bar plots. 

 

Tables

 

Tables are OK. 

 

 

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

Overall this is a very thorough and well described study, with clear value for many stakeholders. The length of the study (10 years) is commendable, and allows for a variety of different relationships between seed availability and small mammal populations to be explored. This has clear relevance in the face of projected climate change in the region over the coming decades. I would also like to commend the authors on the clarity of their data analysis section, and the overall reporting and interpretation of results. Please find a selection of comments below, which I think could improve the quality and clarity of the manuscript as presented:

Line 23: Other variables were not considered or incorporated into analyses (e.g. temperature or precipitation). Is there a reason these were not included? I think including them and re-running analyses would give a much more holistic picture of the determinants of seed availability and small mammal populations. This would be useful as climate and climate change are frequently mentioned in the manuscript, yet cannot really be explored further as climate is not really included in the analyses. 

Line 36 – 28: This statement needs a reference.

Line 41 – 43: This statement needs a reference.

Line 45 – 46: This statement needs a reference.

Line 50 – 51: This statement needs a reference.

Line 51: “This reproductive strategy” needs to be defined before this statement can be made. I suggest restructuring of this paragraph to explain the strategy first.

Line 54: Suggest rephrasing to “locally synchronises”.

Line 59 – 61: I would suggest rephrasing the statement “Understanding the mechanisms regulating this relationship…” as this study does not look at the mechanisms regulating the relationship, rather it just describes the relationship itself over a 10 year period. This could be used in the discussion instead as avenues for future research.  

Line 69 – 70: This statement needs a reference.

Line 69 – 80: This statement needs a reference.

Line 153: Figure 1 – all sampling location dots are too small and should be increased in size. Scale bars should also be made bigger. The figure legend should also mention the location of sampling. Overall I would like to see a mention of why and how were mammal and seed sampling areas were selected, as the seed sampling areas are all relatively close to one another, while mammal sampling areas are more dispersed. Surely better to try and match both sampling locations?

Line 168: Longworth trap dimensions should be included for comparison.

Line 170: How often were traps alternated?

Line 191: Figure 2 – Why is 5 split into 5a and 5b? Also what 1-7 represents should be discussed in the figure legend.

Line 209: Why were multiple pairwise-comparisons not conducted to look at between species and/or plot variation, as the Kruskal-Wallis test had a significant result (Line 249 – 250).

Line 216: What is a “seed index” and how was it calculated?

Ine 240 – 241: The difference in AICc values should be greater than or equal to 2 units for model selection and variable retention, not less than as stated. If a variable is to be added or retained in a model, then it must lower the AICc by at least 2 units. Model selection could be elaborated upon to describe how and when variables were added/removed.

Line 251: Can this statement not be statistically tested?

Line 258: Figure 3 – suggest adding axis labels and axis lines to aid in readability.

Line 276: This result of positive interaction between season and previous year seed availability is interesting, suggesting more animals are then present the following year. If this is the case, why do you think your model results show a negative correlation between the singular variable “Seed of the previous year” and A. sylvaticus populations, as shown in Table 2 (-0.03*)?

Line 293 – 294: This is an interesting result, but rather than saying there was no effect, I would suggest including the model results and explaining that no variables were retained in the final models.  

Line 296: Figure 4 – Add axis labels for year. Also please clarify graph, as "spring seeds" in the legend above suggest that seeds were counted in spring, but I think this is supposed to mean populations of mammals in spring, overlayed against previous autumn's seed counts.

Line 324: “suggesting a potential role for arboreality” requires rewording for clarity.

Line 325: Suggest rewording, as you did not investigate breeding strategies in this paper (e.g. litter sizes, survivorship etc.).

Line 423: Misspelling, should be “experience” and not “experiment”.

Line 729: Why are models shown for only 2 out of 4 species? Also, what Models 1-3 represent should be better described. I presume these are the three best performing models with AICc, and that you selected the lowest AICc from these (Model 1 in each case)? If so, then I question why Model 1 for A. sylvaticus was chosen and reported, as AICc values would suggest Model 2 is the best performing model, as the addition of the variable “Seed of the same year” to Model 1, although significant, does not lower the AICc value by >2 units. The same can also be said for the ” Order 0 (Richness)” models reported.

Comments on the Quality of English Language

Overall the quality of English is good, but there are frequent minor issues, as shown below. These are just a couple of examples, but there are many throughout which will need to be rectified, but do not impact the scientific soundness of the work. 

Line 33: should be "are a" and not just "a"

Line 73: "droughts" should be singular

Line 87: should be "elevated" and "generate", whereas "elevates" and "generates"

Line 91: Should be "ecosystem forests" and not "ecosystems forest"

Line 95: should be "such as wood mice" and not "as wood mice".

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

thanks for addressing the comments.