Unravelling Seascape Patterns of Cryptic Life Stages: Non-Reef Habitat Use in Juvenile Parrotfishes
Round 1
Reviewer 1 Report
In this paper, the authors examined the occurence patterns of parrotfishes known as important fish group in tropical coastal area, in particular, coral reefs, among various habitats with the spatial proximity in the Philippines. The manuscript is well written and structured. One of most intriguing points is that the authors used DNA information to identify juvenile fishes and clarified the characteristic of their spatial distribution patterns compared with adult fishes. I think the findings are new and can be published in this journal. Please consider my suggestions below.
About the BLAST Confidence in Table A1, I could not understand how the authors categorized as "High" "Medium" and "Low" (Score?). Please clarify. And accession numbers on sequences obtained in this study should be provided. And molecular phylogenetic tree using COI sequences used in this study and neighboring species would be informative for readers to grasp the degree of resolution of species identification.
One concern is whether their observation and sampling efforts cover sufficient species diversity of parrotfish or not. Analysis of gamma diversity (how many species occurred according to the number of sites) may be helpful to solve this concern. iNEXT package in software R may be helpful.
Line 96: "While typical studies"->"Typical studies"
Table 1: "All = observations across all habitats" seems confusing. "All = observed or not across all habitats"?
Table 2: please add the information on "High" "Mid" "Low".
Line 502: "KS"->"K.S"
Author Response
Please see the attachment
Author Response File: 
Author Response.docx
Reviewer 2 Report
I feel this is a long overdue study that investigates the juvenile distribution of arguably one of the most conspicuous and important groups of fishes comprising coral reef fish assemblages. While the study itself is very straightforward, it quantifies important links between nursery and adult habitats through the assemblage structure of the species and life phases in each. This is the type of follow-up work that Bellwood and Choat (1989) were attempting to elicit, so it is great to finally see this carried out. Further, the region of study (considering the high diversity of habitats and species) was appropriate for this endeavour.
I did find that some of the language in the introduction could be tightened to reduce wordiness and sometimes redundancy (Exs: line 24, 'taking in to account' versus 'accounting for'; line 38, 'which in turn contributes to adult populations'), so I would encourage the authors to go over the language again throughout.
Line 32-34: This final sentence of the abstract could be stronger, as these results (not 'data' per se) are not lacking anymore
Line 93: sex instead of gender
Line 102: 'adult parrotfishes'
Line 302 and elsewhere: Chlorurus spilurus and sordidus are both used throughout the manuscript
Line 340: I suggest a stronger first sentence of the discussion, something to tuly summarize the importance of this study; suggestion: "This study demonstrated considerable use of non-reef habitats by juvenile parrotfishes, with ontogenetic shifts representing prevalent and important life-history transitions for many species."
Line 351: I think this has been rectified in the text but the lack of congruence between juvenile and adult values for psittacus appears to represent the only weakness through site pairings for the study.
Lines 412-425: One point could be made here: Your results provide a mechanism for the variability in parrotfish assemblages observed on oceanic islands (Taylor et al 2015 Ecography) which are clearly heavily influenced by the island-scale variability in available habitat types associated with different island types. Seeing as long-term larval dispersal at this scale is not very limiting, I think it's easy to argue the importance of a nursery habitat bottleneck driving adult assemblages.
Line 428: "Seminal work [...] shows"
Author Response
Please see the attachment
Author Response File: Author Response.docx
