Citizen Scientists Showed a Four-Fold Increase of Lynx Numbers in Lithuania

Round 1

Reviewer 1 Report

This paper provides a good use of historical data and new citizen science collected data.  I would like to see more discussion on the limitations of all the data used and if this could potentially account for increase in detections of lynx.

Line 28- I think it would be more clear to mention countries here instead of an old and historical country range. Many people reading this paper would likely not be familiar with the historical borders of Russia into eastern and central European countries

Line 45 EU Habitats Directive

Line 64-65:  Information about the habitat make up of the lynx should not be in the methods. Better suited for introduction or discussion

Line 70 what is the relevance of the European mink being extinct?  If none, I would remove.

Line 71 requires references.

Line 77 City or municipality names are hard to read and probably do not add additional information.

Line 86 What is considered field evidence? Examples would be useful here

Line 91 Use lynx not animals

Line 97 is there a difference between physical evidence and field evidence? If not, be consistent.

Line 107.  I am not sure what you mean by share of occupied forest districts. 

Author Response

Reviewer 1:

Comment: This paper provides a good use of historical data and new citizen science collected data.  I would like to see more discussion on the limitations of all the data used and if this could potentially account for increase in detections of lynx. 

Answer: Volunteers did not provide sufficient information in several administrative districts where presence of lynx was detected during the snow-track survey (see Table S1). The apparent under sampling occurred despite our efforts to promote volunteer engagement. Nevertheless, the volunteer efforts to monitor lynx population in Lithuania did provide information when snow-track counts were not possible. Additionally, we were concerned on the unevenness of sampling despite all means of promoting participation and informing participants as suggested by Resnik et al. (2015). Many observations were obtained with camera traps and we indicated that exact locations would not be revealed in subsequent reports because confidentiality of volunteer observations may be crucial for their participation (Bowser et al. 2014).

However, this was already discussed in our paper for wolf (Balčiauskas, L., Balčiauskienė, L., Litvaitis, J. A., & Tijušas, E. (2020). Adaptive monitoring: using citizen scientists to track wolf populations when winter-track counts become unreliable. Wildlife Research). To avoid limitations, we proposed several measures, which we add to the Discussion part in shortened version with the relevant reference. These means for sure can increase data flow.

Comment: Line 28- I think it would be more clear to mention countries here instead of an old and historical country range. Many people reading this paper would likely not be familiar with the historical borders of Russia into eastern and central European countries

Rebuttal: we think, this is simple misunderstanding. Borders of Russia did not change, and it was never expanded into eastern or central Europe – USSR was, but this was not a country, just union. We had in mind namely Russia, as is written.

Comment: Line 45 EU Habitats Directive

Answer: added

Comment: Line 64-65:  Information about the habitat make up of the lynx should not be in the methods. Better suited for introduction or discussion

Answer: listed habitats and their percents are related to the country territory, not for lynx. We changed wording in the text.

Comment: Line 70 what is the relevance of the European mink being extinct?  If none, I would remove.

Answer: not relevant, deleted.

Comment: Line 71 requires references.

Answer: we mowed references one sentence further in the text.

Comment: Line 77 City or municipality names are hard to read and probably do not add additional information.

Answer: municipality names are the same as in the Table S1, therefore removing names will cause loss of the spatial representation. We hope that in the final version all names will be better readable, as we provide high resolution images separately.

Comment: Line 86 What is considered field evidence? Examples would be useful here

Answer: Tracks, scats and prey remains – added to the text.

Comment: Line 91 Use lynx not animals

Answer: changed as advised.

Comment: Line 97 is there a difference between physical evidence and field evidence? If not, be consistent.

Answer: we stick to field evidence, now listed in Line 86.

Comment: Comment: Line 107.  I am not sure what you mean by share of occupied forest districts. 

Answer: changed to “number”.

Reviewer 2 Report

Dear Authors

your MS 'Citizen scientists showed a 4-fold increase of lynx numbers in Lithuania' is in my opinion well structured and clear, and is an excellent example of how different research techniques, including 'citizen science' can be synergistic and valid to obtain good results. Although apparently and more of local interest, this study represents a valid instance applicable in every territorial area well controlled.

Please at line 73 changes 'invasive' to 'allochthonous' which makes it better that they are non-native species. The fact that they are invasive is secondary and consequent. In fact different is the example regarding the golden jackal, this can be considered invasive even if authochtonous.

Author Response

Reviewer 2:

Dear Authors

your MS 'Citizen scientists showed a 4-fold increase of lynx numbers in Lithuania' is in my opinion well structured and clear, and is an excellent example of how different research techniques, including 'citizen science' can be synergistic and valid to obtain good results. Although apparently and more of local interest, this study represents a valid instance applicable in every territorial area well controlled.

Answer: thank you for the positive evaluation of our manuscript.

Comment: Please at line 73 changes 'invasive' to 'allochthonous' which makes it better that they are non-native species. The fact that they are invasive is secondary and consequent. In fact different is the example regarding the golden jackal, this can be considered invasive even if authochtonous.

Answer: In Lithuania, there is a list of invasive organisms, so in we try to balance with it. Therefore, we added “allochthonous” to the first three species listed. Golden jackal is also allochthonous. Text now is “Three carnivores, raccoon dogs (Nyctereutes procyonoides), American mink (Neovison vison), and raccoons (Procyon lotor) are allochthonous and invasive. Golden jackals (Canis aureus), first reported in 2015, are also allochtonous, but not considered invasive [32].”