Using a field survey, this study examines the association between mercury contamination and avian influenza in waterfowl in California wetlands. Waterfowl representing 11 species were sampled during the winter months to assess how prior and current infection were related to mercury contamination. Additionally, the authors examined body condition of the birds. In brief, the authors found that higher mercury concentrations were associated with infection (prior and current) but limited evidence for alterations in body condition. Overall, this was a nicely done study. The motivation was clear and concise, the methodology was solid, and the data analysis and interpretation was straightforward. It was also well written. I just have a few minor comments and suggested edits on the manuscript.

1) Lines 88 - 95. For the hypotheses, I would delete the '(i)' and '(ii)' calling out each hypothesis. Typically, this format is used when all the hypotheses are listed in the same sentence but these are addressed in different sentences so it read a bit awkward.

2) In the statistical analyses section, the authors mention date^2 in the models. However, it's not clear what this accomplishes beyond the use of date alone. Please clarify it's inclusion the models.

3) In the results for prior infection, the authors occasionally use the 'recent' or 'recent prior'. Some readers might confuse recent with active so I recommend just sticking with prior infection to make the distinction clear in the results. Note this is also in Figure 3.

4) Lines 289 - 290. The odds that are presented in this line are not presented in the results and I can't determine how they were obtained.

5) Line 340. Please include some values for mercury concentration benchmarks for those unfamiliar with the system.

The authors have adequately addressed all of comments on the previous version. I have no additional comments on the paper.