Unexpectedly, Creation of Temporary Water Bodies Has Increased the Availability of Food and Nesting Sites for Bees (Apiformes)

Round 1

Reviewer 1 Report (Previous Reviewer 1)

Dear authors, thank you for taking the time to carefully address my comments. I have a few more comments following your revisions.

The new Figure S1 helps illustrate the extent of urbanization surrounding your study area, but I also recommend adding a sentence or two describing this in the Methods, because many readers will not look at the supplementary files. For example, in the first paragraph of section “2.1 Study Area” you could add: “The study area is a suburban forest situated on the outskirts of the city of Bydgoszcz. Residential districts are close to the southern border of the study area (ca. 150 m to 1.6 km away), the eastern border (ca. 350 m to 1.4 km away), and the western border (ca. 1.1–2.0 km away). Only from the north it borders on a pure pine stand. These areas are subject to various forms of human impact, associated with forest management and recreation.”

In lines 55-61 you added discussion about bee preferences for native vs. exotic plant species, as I suggested, but the sentences that you added were copied directly from Stewart et al. (2018) (page 13, section "Native versus exotic plant species"). Please re-word these sentences to avoid plagiarizing Stewart et al.

Regarding your addition at lines 110-112, you say that “5 were partly filled with water for 5 months.” What about the other 13? Were they completely filled with water throughout the duration of the study? Or completely dry during the study? Please clarify.

Your revision at lines 247-248 does not make sense. Poisson GLMM does not account for temporal and spatial correlations. The original sentence was correct (the Poisson distribution is used with non-negative integers), so I suggest reverting back to your original sentence. You may state that the random effects (for site and month) were included to help account for spatial and temporal autocorrelation.

You state that you added details about which post-hoc test was used, but I don’t see it in the revised MS.

Regarding my comment about the symbols for Figures 3-14, I didn’t mean that you should use different letters for each habitat type. I meant that you could use 4 different symbols, e.g., crosses, circles, triangles, asterisks (stars)

In your response you state “The VIF for the investigated variables was lower than 10%, which allowed us to leave them in the analysis.” Please include this information in your MS also.

Author Response

Comments and Suggestions for Authors

Dear authors, thank you for taking the time to carefully address my comments. I have a few more comments following your revisions.

The new Figure S1 helps illustrate the extent of urbanization surrounding your study area, but I also recommend adding a sentence or two describing this in the Methods, because many readers will not look at the supplementary files. For example, in the first paragraph of section “2.1 Study Area” you could add: “The study area is a suburban forest situated on the outskirts of the city of Bydgoszcz. Residential districts are close to the southern border of the study area (ca. 150 m to 1.6 km away), the eastern border (ca. 350 m to 1.4 km away), and the western border (ca. 1.1–2.0 km away). Only from the north it borders on a pure pine stand. These areas are subject to various forms of human impact, associated with forest management and recreation.”

      Reply: Thank you for this valuable suggestion. We have added the above sentences to the manuscript.

In lines 55-61 you added discussion about bee preferences for native vs. exotic plant species, as I suggested, but the sentences that you added were copied directly from Stewart et al. (2018) (page 13, section "Native versus exotic plant species"). Please re-word these sentences to avoid plagiarizing Stewart et al.

 Reply: Thank you. We have re-worded these sentences.

 Regarding your addition at lines 110-112, you say that “5 were partly filled with water for 5 months.” What about the other 13? Were they completely filled with water throughout the duration of the study? Or completely dry during the study? Please clarify.

Reply: The other ponds and ditches were completely dry during the study. We have added this information to the manuscript.

Your revision at lines 247-248 does not make sense. Poisson GLMM does not account for temporal and spatial correlations. The original sentence was correct (the Poisson distribution is used with non-negative integers), so I suggest reverting back to your original sentence. You may state that the random effects (for site and month) were included to help account for spatial and temporal autocorrelation.

Reply: Agree.

You state that you added details about which post-hoc test was used, but I don’t see it in the revised MS.

Reply: Thank you for your comment. We did not use a post-hoc test. This is because a post-hoc test is done when simply comparing groups. We want to take into account spatial and temporal correlations, so we did a mixed model. In such a model, there is no need to do a post-hoc test.

Regarding my comment about the symbols for Figures 3-14, I didn’t mean that you should use different letters for each habitat type. I meant that you could use 4 different symbols, e.g., crosses, circles, triangles, asterisks (stars)

Reply: We would suggest leaving the figures in their original form.

In your response you state “The VIF for the investigated variables was lower than 10%, which allowed us to leave them in the analysis.” Please include this information in your MS also.

Reply: Done.

 Best regards,

Anna Sobieraj-Betlińska

Author Response File: Author Response.docx

Reviewer 2 Report (Previous Reviewer 3)

Dear authors, 

This manuscript describes a study examining bee abundance and richness in 4 habitat types (forests, clearings, ditches, and basins) located within a water intake facility. The authors found that bee abundance and richness were higher in clearings, ditches, and basins, compared to forests, and also found that cover of woody vegetation, degree of shading, and radius of surrounding open habitat are the most influential habitat characteristics. The study was carried out in sides which were only a few hundred km of each other, but overall the study is sound and the results are interesting. Many species may travel more than 5Km in food search, but is difficult to find areas like the study area. Also, you collected species and you tried to note the species for 5 months, which means 2160 samples. For someone else, this work may be not enough, but having work in the field, this part is very difficult. 

Here are my minor comments: 

lines 142-144: please give more information

lines 151-154: write it again giving and be more specific or present it better

Lines 157-169: please find a way to present it better, giving the reader an easy way to understand better

 Lines 354 - 358: should be transfered to the text, in the legend you should write only the title of the diagram

Thank you 

Author Response

Comments and Suggestions for Authors

Dear authors, 

This manuscript describes a study examining bee abundance and richness in 4 habitat types (forests, clearings, ditches, and basins) located within a water intake facility. The authors found that bee abundance and richness were higher in clearings, ditches, and basins, compared to forests, and also found that cover of woody vegetation, degree of shading, and radius of surrounding open habitat are the most influential habitat characteristics. The study was carried out in sides which were only a few hundred km of each other, but overall the study is sound and the results are interesting. Many species may travel more than 5Km in food search, but is difficult to find areas like the study area. Also, you collected species and you tried to note the species for 5 months, which means 2160 samples. For someone else, this work may be not enough, but having work in the field, this part is very difficult. 

 Here are my minor comments: 

lines 142-144: please give more information

Reply: Done.

 lines 151-154: write it again giving and be more specific or present it better

Reply: We have corrected this.

 Lines 157-169: please find a way to present it better, giving the reader an easy way to understand better

Reply: Ok.

 Lines 354 - 358: should be transfered to the text, in the legend you should write only the title of the diagram

Thank you

 Reply: Yes, right remark. Done.

Best regards,

Anna Sobieraj-Betlińska

Author Response File: Author Response.docx

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

This manuscript describes a study examining bee abundance and richness in 4 habitat types (forests, clearings, ditches, and basins) located within a water intake facility. The authors found that bee abundance and richness were higher in clearings, ditches, and basins, compared to forests, and also found that cover of woody vegetation, degree of shading, and radius of surrounding open habitat are the most influential habitat characteristics. The scope of the study is quite small (all study sites in the same facility, and all within a few hundred km of each other), which limits the conclusions than can be drawn, but overall the study is sound and the results are interesting. I have a few main comments and several minor ones that may help improve the manuscript.

Main comments:

1. he introduction is a bit misleading. It focuses on urbanization, leading me to believe that this study was conducted in an urban environment (e.g., a city). It was actually conducted in a water intake facility, which primarily consisted of forested habitat, with several man-made ditches, basins, and clearings. I suggest that the introduction be revised to focus on anthropogenic disturbance/development within natural habitats.
2. I found many sections of the Methods confusing and unclear, and I suspect that other readers will have the same confusion. Please revise the Methods to improve clarity (and see my comments below for specific points that were unclear/confusing).
3. Some of the results were not discussed in the Discussion, such as why more species were predicted at basins than ditches, and possible explanations for the different habitat preferences of polylectic, oligolectic, cleptoparasitic, soil-nesting, and hive-nesting bees.
4. As mentioned, the scope of the study is quite small, so I suggest you address this in the Discussion, and recommend that additional studies be conducted to verify/support your findings.

Minor comments:

5. 29-41: I suggest combining the first two paragraphs, since the first paragraph is so short (2 sentences) and they are about the same topic (urbanization).
6. L43, 48 (and other places throughout the manuscript): Change wording from “In respect of…” to “With respect to…”
7. L53-55: Several studies have found that bees do not have a preference between native and exotic plant species, or actually prefer exotic species: Matteson & Langellotto 2011, Hanley et al. 2014, Stewart et al. 2018
8. L92: Please include the country, as many readers will not know where Bydgoszcz is, and it is useful to know where, in general, the study was conducted (e.g., temperate vs. tropical).
9. L91-105: Please include a description of the ditches and basins. I initially assumed that they were always filled with water, but after reading the full MS it seems like they are often not filled. Please explain how often they are filled versus dry, whether they are usually partially or completely filled, and any other info that you think is relevant.
10. L109: For the infiltration ditches and basins, were the traps and transects along the water edge? Or at a fixed distance from the water edge? Please include this info in the Methods.
11. L118: You have 27 sites, and at each site you placed 4 traps, so should that be 108 traps, not 64?
12. L135: The same transects that bees were sampled along?
13. L135: Does “dry places” refer to areas inside of the ditches and basins that were dry, or to areas along the edge of the ditches and basins? Does “flooded” places refer only to areas with standing water (plants were aquatic species) or does it include marshy/muddy areas along the ditch or basin edge? Please clarify.
14. L136-137: Please provide details, as most readers will likely not know what the “broadened Braun-Blanquet scale, modified by Barkman et al.” is.
15. L146-153: I am confused by this section. What is considered “very dry” versus “dry” versus “intermediate between very dry and dry”, etc.? How did you measure soil moisture? Did you measure the surface soil, or at a fixed soil depth? Or were these categories based on the plant species that grew there, and if so, which reference(s) did you use?
16. L154-158: This section is also not clear to me. What is the “radius of a belt”? Does this mean you examined plants within a fixed radius around each site? What is the distance of the radius? And you examined only “predominantly open habitats”? What about forest sites, which don’t have open habitats? And the ditches and basins also appear to be surrounded by forest, based on Figure 1. I also don’t understand “herbaceous plants and seedlings of woody plants < 60%”; are you referring to the percentage of area in each site that had less than 60% coverage by herbaceous plants and seedlings of woody plants? [Note: after reading the results, I think I understand variable C9 better, but I still recommend revising your description of it in the Methods section, since it is likely that other readers will also find this description unclear/confusing.)
17. L156: I think the term “site area size” is more clear than “site area”
18. L175: How did you measure degree of shading? According to Table 1, sites 8 and 9 are in clearings, but they have a mean degree of shading equal to 100, same as the forest sites. Also, for the ditches and basins, did you include areas covered by water in your estimation, or only dry areas?
19. L176: So C14 and C15 were only collected for ditch and basin sites? For C14, how often were they assessed for water?
20. L202-223: Please also explain which post-hoc test was used to examine significant differences between habitat types after the GLMM.
21. Figures 3-4: Rather than using the same symbol (crosses) for all 4 habitat types, it might be useful to use a different symbol for each habitat type.
22. L313-317: Aren’t woody vegetation coverage, degree of shading, and the radius of surrounding open habitat all correlated? I would expect sites with more woody vegetation to have more shading and less surrounding open habitat. That would make them intercorrelated, i.e., not independent, which is problematic for many statistical analyses. Is it acceptable to use intercorrelated variables in redundancy analysis, and is the analysis able to handle such non-independence?
23. L344: What is “cultural landscape”? I am not familiar with this term. Do you mean that disturbed areas can increase the species richness of monoculture or homogenous landscapes?
24. L390-405: This paragraph covers several seemingly unrelated topics, and I find it confusing. The first sentence (traditionally the topic sentence) talks about how plant diversity is linked with herbivore diversity, leading me to believe that was the topic of this paragraph. And I found it confusing that the authors wanted to discuss herbivore diversity, since herbivores haven’t been mentioned the entire manuscript. Then, it goes on to discuss the following topics: habitat heterogeneity, habitat destruction, empty niches, water in the basins and how it relates to soil moisture, and how soil moisture then shapes plant communities. I didn’t follow the logic of this paragraph, and it doesn’t seem relevant to your study (except for the last part that explains about water in basins and how soil moisture shapes plant communities).
25. L421: Is it supposed to be herbaceous plants and seedlings of woody plants LESS THAN or GREATER THAN 60%? Throughout the MS, you use less than 60%, but this doesn’t make sense to me. Shouldn’t “open habitats” mean there is at least 60% herbaceous and woody seedlings? (i.e., less than 40% trees)
26. L424-426: This sentence seems unconnected to the rest of the paragraph.
27. L428-441: I also find it interesting that C2 (mean cover by flowering species) was not significant, as many studies have found that bee abundance and/or richness is often positively correlated with floral abundance. Do you think mean cover by flowering species is perhaps not as important as the number of flowers? Did you collect information on floral abundance?
28. Very minor errors in English use that do not affect the clarity of the writing, but should be corrected before publishing.

Reviewer 2 Report

The research is well presented and of interest to the field but the sites are too close to each other spatially to be independent from a statistical standpoint.  Most bees could easily fly between the sites you sampled. Additionally, I think you need to tone down the parts where you talk about the differences between wooded habitats and the others (all more open), especially since you didn't sample in the trees.

Minor comments:

• L29 “Urbanization contributes to changes in land cover” rather than “land use” (Line 33 too)

• L30 “its” refers to urbanization, right? Then, why is taxonomic group listed in that sentence?

• L67 please specify the city or region where you have documented these changes

• L156 what was the spatial resolution of the aerial photos

• L336 needs a reference

Reviewer 3 Report

The present study was about the creation of temporary water bodies has increased the availability of food and nesting sites for bees (Apiformes). 

The authors presented the subject in high level and the whole experiment was well organised. 

In the attached pdf you will find some comments and some suggestion. 

Generaly, is very good work providing a lot of information to the readers and many answers about the behaviour of the most important pollinators in the world 

Thank you for the work

Comments for author File: Comments.pdf