Consistent Monthly Reproduction and Completion of a Brooding Coral Life Cycle through Ex Situ Culture

Round 1

Reviewer 1 Report

This is a competent study relevant to current endeavors focused on ref building coral propagation. To my mind the most important aspect is the comparison of coral reproductive performance in the recirculating versus flow-through aquaria.  I would encourage the authors to reflect on their comparison of the two aquaculture systems and extend the Discussion to aspects relevant to aquarium systems more broadly, for example flow-through systems at marine filed stations around the tropics. Some perform better than others in maintaining corals, o this work could help point to the most critical attributes needed.

 

I recommend the Authors read the paper by Jokiel et al (1985), where Pocillopora damicornis  corals were maintained in flowthrough aquaria at the Hawaii Institute of Marine Biology for 16 months and appeared to planulate regularly. This study of planulation in a similar coral is relevant. (Marine Biology 88:167-174)

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Dear Authors

 

Overall, this was a well written and well  organized paper, with a good structure of the different sections. The language was very good, with only a few comments on word choice and grammar. Below I give some comments, suggestions for changes, and questions that came to mind while reading. The manuscript is already well worked through and only very minor corrections is necessary. The rest are suggestions that you can do with what you like.

 

Abstract: you don’t mention that the RAS cultured coral colonies were significantly smaller than those cultured in FTS. It’s an important result that shows that there is work to be done on improving feeding routines or water chemistry in RAS.

 

Line     Comment

29        word choice? ‘tangible’ – this word doesn’t seem to fit in the sentence –            meaning:  perceptible by touch, palpable

 Suggestion: This demonstrated that the use of ex situ aquaculture…or This demonstrated the potential use of ex situ aquaculture…

 

48        cultivation of corals, not for

55        aquaculture systems, or aquaculture system tanks

65        ‘however’ is superfluous, better to remove it

69        tautology, reproductive strategy and reproduce in the same sentence. Suggestion: …especially relevant to corals with an annual reproductive strategy. /or: …especially relevant to corals with a single annual spawning event. …/or: …especially relevant to corals with a reproductive strategy encompassing a single spawning event. You might want to add broadcast spawning (e.g., on line 74) to make it clear what kind of spawning strategy you mean, as a contrast to brooding and planulation.

120       Any idea of what caused the mortality?

 

Section 2.3 Artemia preparation and coral feeding

I’m wondering about the feasibility of scaling up this rearing method. It seems like a labor-intense practice to move the corals to another tank for feeding.

 

205      “Reproductive output was not assessed on weekends when corals had stopped reproducing (i.e., the interim time between reproductive cycles).” – was the output assessed for other weekends? Or did you just take weekends off and didn’t assess output? This sentence needs some more explanation.

207      Is the time between fertilization and planulation known? How long does the embryo development take until there is a mature larva that can be released?

233      The figure reference for figure 1f should be placed at the end of the previous sentence. Putting it after a description of linear extension and reproductive output makes you think it’s referring to a graph with results.

300      An i missing in Neither

 

Figure 2

            It would be useful to mention that the FTS data is shown in blue and the RAS data is shown in green in all the graphs as a general guidance for the readers.

 

Figure 4

            The explanations for a) and b) is missing in this caption

 

373      The values of linear extension (mean ±SD) in the F1 corals at the end of the 8-month culturing period should be given in the text as well. And the x-axis in figure 5b should have the proper unit stated (I assume cm?)
Total linear extension (cm)

 

Figure 5

            Any idea why the three extremely productive corals in FTS could produce so much planulae?  Was it fused colonies with several recruiting planulae able to produce a larger colony faster? What did the F1 larvae settle on, what was the substrate, and how many larvae per substrate? How were the larvae introduced to the substrates? In one big tank or split up in several? Any gregarious settling giving some new colonies an upper hand? I’d like to see a little bit more information here. Figure 1f is too small to make out the substrate and number of colonizers.

 

Discussion

392      Spell out the species name and the aquaculture systems the first time they are mentioned in the Discussion.

399      Any idea why the corals in the FTS grew faster? Most nutrients and total alkalinity were higher in the RAS (Ca, Mg), but flow/turbulence was lower (line 128). Could this have anything to do with it? Bacterial composition of the FTS and RAS cultured corals could perhaps differ? Feeding regime were the same. Any other potential and essential nutrients or bacteria coming in with the natural seawater?

430      Is it known if sperm release is continuous over the year, or annual/seasonal? Any seasonal difference in sexually or asexually produced planulae?

 

Conclusions

573      ‘tangibility’ does not seem to be the proper word here – consider changing to the potential for long-term culture

Author Response

Please see the attachment.

Author Response File: Author Response.pdf