Hemispherical Distribution of Antarctic Krill Indicates High Abundance in Amundsen Sea

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Dear Sir,

I would like to thank you for selecting me as a reviewer for this research entitled (Hemispherical distribution of Antarctic krill indicates high abundance in Amundsen Sea). The researchers have put in a great effort in collecting and analyzing the data, and then writing this research in the best possible way. According to the publishing house's rules, the abstract should not exceed 200 words. However, I think it would be easy to reformulate the abstract to 200 words. There is also an error in line 230.

I wish the researchers and you all the best.

Author Response

See table in the annex to the attached covering letter

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Review for the paper "Hemispherical distribution of Antarctic krill indicates high abundance in Amundsen Sea" by Molly Thornborrow, Andrew S. Brierley, Roland Proud, Inigo Everson, Joshua Lawrence, Matteo Bernasconi, Paul G. Fernandes submitted to "Oceans".

In the Southern Ocean, euphausiids play a central role as an important link between primary producers and higher trophic levels, including many important organisms such as fish, seabirds and marine mammals. Changes in krill density can alter trophic pathways and ecosystem functioning, often with significant consequences for higher trophic levels. Understanding the important role of euphausiids in marine ecosystems and ocean productivity has motivated substantial efforts to investigate the spatio-temporal patterns of their abundance in relation to oceanographic variability and climate forcing. Despite recent advances in the study of krill ecology, several issues require further attention. The authors focused on the relationships between krill swarms and atmospheric methane concentrations to reveal the role of methane emissions in the region. The study is based on a comprehensive data set. The main results are statistically confirmed and clearly visualized. I have only minor suggestions to improve the ms.

Specific remarks.

Section 2.5. Indicate the height above sea level at which the methane concentration was measured.

L239. Consider replacing "compared" with "correlated".

Discussion. Section 4.1. What about other factors that might be responsible for krill distribution? At the very least, predation pressure should be mentioned as a cause of spatial variability in total euphausiid abundance.

Discussion. Section 4.2. Consider the effect of vertical migration on shoaling characteristics. Were there differences between day and night records?

Discussion. Section 4.3. Methane concentration showed low variability according to section 3.4. Although the authors show a significant negative correlation between euphausiids and methane, their conclusion on the role of euphausiids in these processes is somewhat unclear. A more in-depth discussion of methane sources and the influence of plankton metabolism on atmospheric methane is suggested.

References. According to the International Zoological Nomenclature, the Latin names of species and genera must be written in italics. Please check this point carefully. See L 582, 589, 621, 623.

Author Response

See table in the annex to the attached covering letter

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Please see attached document with comments

Comments for author File: Comments.pdf

Author Response

See table in the annex to the attached covering letter

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

I have reviewed the author's responses and my comments have been adequately addressed. I now recommend the manuscript for publication. No further comments.