Bigmouth Buffalo Ictiobus cyprinellus sets freshwater teleost record as improved age analysis reveals centenarian longevity

Understanding the age structure and population dynamics of harvested species is crucial for sustainability, especially in fisheries. The Bigmouth Buffalo (Ictiobus cyprinellus) is a fish endemic to the Mississippi and Hudson Bay drainages. A valued food-fish for centuries, they are now a prized sportfish as night bowfishing has become a million-dollar industry in the past decade. All harvest is virtually unregulated and unstudied, and Bigmouth Buffalo are declining while little is known about their biology. Using thin-sectioned otoliths and bomb-radiocarbon dating, we find Bigmouth Buffalo can reach 112 years of age, more than quadrupling previous longevity estimates, making this the oldest known freshwater teleost (~12,000 species). We document numerous populations that are comprised largely (85–90%) of individuals over 80 years old, suggesting long-term recruitment failure since dam construction in the 1930s. Our findings indicate Bigmouth Buffalo require urgent attention, while other understudied fishes may be threatened by similar ecological neglect.

Line 69 ", so and" something missing here? Line 85 "With the exception of Pennsylvania.." maybe replace with "In Pennsylvania …" Line 101 "estimated the age" Line 118 Please explain expected 14C levels / reference records -might not be clear to the reader what this at this point Line 127 For reference records shown this surely appears to be the case, however, as also stated elsewhere freshwater reference records are rare -so can you be sure this is always the case for all freshwater systems? (I think not -I believe these may be very complex and site-specific due to geology, geochemistry, hydrology and so forth) Line 128 I think 'expectation' is an overstatement. Are these freshwater reference curves universal to the extend that you may expect other data to follow the curve? I would slightly weaken the statement. Line 135 please explain what you mean with 'expected' Line 142 this is more comment to statement above. This exactly shows that freshwater systems are complex and variable, and hence that reference curves for freshwater systems must be considered local.
Line 194 I don't think you can state that 14C bomb dating can reveal ages older than 1960 -50. I am a little ambivalent on what to think here. Clearly 14C bomb dating is important in order to make this conclusion, however, what you really do is to verify your otolith annual counts using the bomb rise. On its own 14C cannot be used to infer the old age (unless you construct a model e.g. Nielsen et al, Science, 2016). Maybe attach a small explanatory paragraph after the sentence Line 214 Would change to "timing of the rise" is similar. As correctly explained in line 217. It may read as curves are similar. Line 19. Well couldn't this be due to catchment processes or precipitation delivering a 'terrestrial' DIC/DOC signal to the lake? I don't think residence time alone explains (or at least other possibilities should be mentioned) this. Numerous catchment processes may deliver enriched 14C to the lake and rivers either directly as DIC or as DOC which may be partly oxidised to DIC. Line 35 surely precipitation plays a role, however, what about land-use, catchment geochemistry etc These are important in delivering carbon to freshwater systems. On top of this carbon cycling and recycling within lakes may further be significant for some lake types.
Line 56 yes -I like that term 'regional' and please add the data from 47 and 48 to figure 3 and 4 Reviewer #2 (Remarks to the Author): I have completed my review of the manuscript "Centenarian longevity for Bigmouth Buffalo Ictiobus cyprinellus" by Alec R. Lackmann, Allen H. Andrews, Malcolm G. Butler, Ewelina S. Bielak-Lackmann and Mark E. Clark. I found this manuscript to be well-written and very interesting. The experimental design is appropriate, yielding clear and important results, that can help fisheries scientists to make better informed conservation decisions.
I've added a few very minor editorial suggestions in WORD Track Changes. The figures are well done and serve to enhance the paper. The paper is suitable for publication in Communications Biology, and I commend the authors for their work. You may identify me to the authors. Line 78-80: minor wording changes in response to Reviewers 1 and 2: Reviewer 1's comment: [formerly] Line 69 ", so and" something missing here? (Reviewer 2 simply made an editorial revision); BMB acronym replaced with common or species name of species (advised by editors in AIP document) Lines 85-86: BMB acronym replaced with common or species name of species (advised by editors in AIP document) Lines 91-97: minor wording changes in response to Reviewer 1's comment: [formerly] Line 85 "With the exception of Pennsylvania.." maybe replace with "In Pennsylvania …" (see track changes document for more details); BMB acronym replaced with common or species name of species (advised by editors in AIP document) Lines 101-106: minor wording changes to the present tense and BMB acronym replaced (advised by editors in AIP document); Line 113: minor wording changes in response to Reviewer 1's comment: [formerly]  Line 142: revision in response to Reviewer 1's comment: [formerly] Line 127 For reference records shown this surely appears to be the case, however, as also stated elsewhere freshwater reference records are rare -so can you be sure this is always the case for all freshwater systems? (I think not -I believe these may be very complex and site-specific due to geology, geochemistry, hydrology and so forth) Line 143: revision in response to Reviewer 1's comment: [formerly] Line 128 I think 'expectation' is an overstatement. Are these freshwater reference curves universal to the extend that you may expect other data to follow the curve? I would slightly weaken the statement.

Line 147: BMB acronym replaced (advised by editors in AIP document)
Lines 149-154: minor wording change to reflect that we no longer have SI (advised by editors in AIP document); revision in response to Reviewer 1's comment: [formerly] Line 135 please explain what you mean with 'expected' Lines 158-159: minor wording change to reflect that we no longer have SI (advised by editors in AIP document); minor wording change in response to Reviewer 1's comment: [formerly] Line 142 this is more comment to statement above. This exactly shows that freshwater systems are complex and variable, and hence that reference curves for freshwater systems must be considered local. See 'track changes' document for more detailed response in the comment section.