Temporal Changes in Bank Vole Populations Indicate Species Decline
Georgy Shenbrot
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsDear Autors,
I found your MS very useful as it summarises the results of years of research on the long term population trends of bank voles in different habitats. Of particular interest are the changes in density over multi-year cycles. The bank vole is one of the most common and abundant species in European forests. Studies over many years are currently rare and therefore the data presented is unique. The text is clearly written and the authors' many years of experience is evident.
I have only a few minor revisions before final acceptance.
In the description of the tables, I would add N - number of trapping sessions - as it is in Table 3.
Figure 3 line 331 - repetition of ‘in autumn in autumn’
The captions of Figures 2 and 3 are repeated
In the Materials and methods chapter, the subsections are written so that the sentence begins with a capital letter and then a lowercase letter. In the other chapters, the subsections are written in capital letters.
This should be standardised.
Author Response
Rev #1 comments and answers
Comment: I found your MS very useful as it summarises the results of years of research on the long term population trends of bank voles in different habitats. Of particular interest are the changes in density over multi-year cycles. The bank vole is one of the most common and abundant species in European forests. Studies over many years are currently rare and therefore the data presented is unique. The text is clearly written and the authors' many years of experience is evident.
Answer: thank you
I have only a few minor revisions before final acceptance.
Comment: In the description of the tables, I would add N - number of trapping sessions - as it is in Table 3.
Answer: thank you for this observation. We acknowledge it adding TS – number of trapping sessions, as N was reserved for the number of trapped individuals in the Tables 1 and 2.
Figure 3 line 331 - repetition of ‘in autumn in autumn’
Answer: corrected, it was another mistake in caption of Figure 3
The captions of Figures 2 and 3 are repeated
Answer: corrected
In the Materials and methods chapter, the subsections are written so that the sentence begins with a capital letter and then a lowercase letter. In the other chapters, the subsections are written in capital letters. This should be standardised.
Answer: corrected, thank you for noticing.
Reviewer 2 Report
Comments and Suggestions for AuthorsMinor corrections and questions are given in the text of the manuscript.
Comments for author File: 
Comments.pdf
Author Response
We present answers to comments written directly in the PDF file.
Comment in Line 57: Craseomys rufocanus. Look, for example - Voles and Lemmings (Arvicolinae) of the Palaearctic Region [Elektronski vir] / authors Boris Kryštufek, Georgy I. Shenbrot. 2022
Answer: corrected as advised.
Comment in Lines 64–65; It cannot be said that representatives of the genus Microtus are "larger herbivorous" compared to C. glareolus
Answer: apologies, this was language problem, Changed to “the cyclicity of the larger species of herbivorous rodents, such as Microtus,”
Comment in Line 71: In the northwest and northeast of Europe, the population dynamics of this species are also noted by other authors (Ivanter, 2008; Bobretsov, 2016)
Answer: thank you, both references included
Comment in Line 165: It would be desirable to describe the type of traps in more detail and note the correspondence or discrepancy with those when compared with data from the literature. Please write about the further fate of the captured voles.
Answer: We used 7 × 14 cm wooden snap traps arranged in lines of 25 traps 5 m apart, with 1–12 lines per habitat. Plastic or metal 7 × 14 cm snap traps and 5 × 10 cm metal traps were used in a few trapping sessions. Text added.
In the most cases, trapped animals were measured and dissected. The cleaned skulls are housed in the collection of the Centre for Nature Research. The material from the captured individuals has been and is being used for diet, reproductive, genetic, pathogen and other studies. Some of the material has been used in collaboration with research institutions in other countries and in joint publications. However, this is beyond the scope of this paper.
Line 180: To what extent is such a large number of captured specimens justified from an ethical point of view?
The material from the captured individuals has been and is being used for diet, reproductive, genetic, gut microbiome, and various pathogen studies. Some of the material has been used in collaboration with research institutions in other countries and in joint publications. In conclusion – material has been collected not only for this paper. As for some studies in commensal and agricultural habitats – small mammals are exterminated by owners, so we are grateful for the presented material. Also, the monitoring of small mammals in the region of the Ignalina nuclear power plant in the 1980s, and the monitoring of small mammals within the National Environmental Monitoring Program in 1993–2005 (with gaps of some years) was carried out on the state level. In flooded meadows and forests, every spring all small mammals were killed by floods. Therefore, there is no ethical point in trapping. In Lithuania, small mammal trapping is allowed by law with permissions not required. Currently, we have an approval form the Animal Welfare Committee of the Nature Research Centre, protocols No GGT-7 and GGT-8, see Back Matter.
Reviewer 3 Report
Comments and Suggestions for AuthorsThis is an interesting and informative paper, that can be published after moderate revision.
One of the problems that I can see, is author’s interpretation of observer pattern of density dynamics of C. glareolus as the decreasing long-term trend. Visual inspection of the data presented in the figures 2 and 3 allowed another interpretation. For the relative abundances averaged by all habitats (fig.2), I can see three periods, 1981-1990 and 2017-2023 with relatively low but stable densities, and 1991-2016 with higher but fluctuating densities. For the relative abundances in forest habitats (fig.3), I can see four periods, accidental density outbreaks in 1975 and 1977, periods with relatively low but stable densities in 1978-1991 and 2017-2023, and the period with higher but fluctuating densities in 1992-2016. Please, discuss these possibilities.
Some other minor notes:
Abstract, page 1, line 20. “This … species plays a certain role in the changing diversity …”. What do you mean writing “a certain role”? Please, be more definite.
Why you define Clethrionomys glareolus as a “northern species” (page 1, line 20; page 3, line 129)? It seems strange for the species distributed in Europe from southern Italy to northern Norway. Please, explain or change.
You use the incorrect Latin name, Myodes rufocanus, for gray-sided vole (page 2, line 57). You use the name Clethrionomys glareolus for the bank vole what assume that you accept the name Myodes as junior synonym of the name Lemmus and not as the senior synonym the name Clethrionomys (see Kryštufek et al. 2020 - Mammalia 84: 214–217). Moreover, gray-sided vole is the member of the genus Craseomys but not Clethrionomys (see Kryštufek & Shenbrot 2022. Voles and Lemmings (Arvicolinae) of the Palaearctic Region. University of Maribor. Maribor, Slovenia). Please, correct.
Please, consider the possibility to place in supporting information your trapping sites with georeferencing information.
The legend to Fig. 3 contains an evident mistyping, “in autumn in autumn independent of habitat” instead of “in autumn in forests”. Please, correct.
Author Response
Please find Answers as attachment
Author Response File: Author Response.pdf
