Identifying Potential Critical Angel Shark Areas in Türkiye, Eastern Mediterranean Based on New Records of Squatina spp. Identified through Fisher Engagement

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript presents a series of relevant data regarding angel shark species, in an area where official records apparently underestimate the occurrence of these species. Through an approach with a strong citizen science component, different information regarding to the capture and reproductive biology of the species was obtained, with relevant and direct impacts on the conservation of the three species of angel shark Eastern Mediterranean Sea. The identification of critical areas for the conservation of angel sharks in the study area versus the description of the fisheries targgeting these species, notably the threat of trawling, could be incorporated into existing fisheries management strategies or those in need of improvement in region. Therefore, the manuscript is important and could directly contribute to a group of elasmobranchs that is highly threatened globally. The study could inspire initiatives in other regions of the world, joining efforts to conserve this peculiar group of sharks. In the end, only a review of possible typing and formatting errors should be done, as there are some signs of errors in line 394 and 456-462.

Author Response

Response to Editor and Reviewers of the submission by Ulman et al. on Angelsharks

 

Please find below the numbered comments (C) of the reviewers, followed by numbered responses (R) in italics.  

 

C1: (Reviewer 1) The manuscript presents a series of relevant data regarding angel shark species, in an area where official records apparently underestimate the occurrence of these species. Through an approach with a strong citizen science component, different information regarding to the capture and reproductive biology of the species was obtained, with relevant and direct impacts on the conservation of the three species of angel shark Eastern Mediterranean Sea. The identification of critical areas for the conservation of angel sharks in the study area versus the description of the fisheries targgeting these species, notably the threat of trawling, could be incorporated into existing fisheries management strategies or those in need of improvement in region. Therefore, the manuscript is important and could directly contribute to a group of elasmobranchs that is highly threatened globally. The study could inspire initiatives in other regions of the world, joining efforts to conserve this peculiar group of sharks. In the end, only a review of possible typing and formatting errors should be done, as there are some signs of errors in line 394 and 456-462.

 

R1: We thank the reviewer for the positive evaluation of our submission and especially for highlighting the importance of this study and its potential applications. We have carefully fixed the grammar errors throughout the manuscript including those on lines 394 and 456-462.

Reviewer 2 Report

Comments and Suggestions for Authors

Please find all comments in the attached file

Comments for author File: Comments.pdf

Author Response

GENERAL COMMENTS:

This article presents the latest information on the occurrence of three angelshark species in Turkish waters based on citizen science data. Authors claimed that their findings as new records from this area. However, when readingthe title, readers may misinterpret this article as a taxonomic report of a new finding of three angelshark species from this region. The fact is those three species are known to occur in the Mediterranean waters but have been rarely reported since decades ago. The

information on the capture-induced parturition events may be important but not significant enough to be put in the title.

 

C1: I suggest changing the title to a sentence that is more representative of the article's context. I suggest changing the title with e.g. “The updated report OR updated information on three threatened angelshark species in Türkish waters based on citizen science data”.

 

R1: We thank the reviewer for their advice here.

The title has been changed to: Identifying potential Critical Angel Shark Areas in Türkiye, Eastern Mediterranean based on new records of Squatina spp. identified through fisher engagement.  

We hope that the reviewer also finds the new title a big improvement as capture induced parturition was removed, angel sharks were generalized and the source of data is presented.

 

C2: The introduction section is too long without a clear research question and the aim of the study. I

suggest moving some information in the introduction to the Discussion section. Detailed comments are listed below:

R2: A research question is now provided in the introduction. We tightened up the Introduction be removing redundant words

C3: What the word “this” refers to?

R3: The sentence with ‘this’ was clarified

C4: Please add supporting reference(s) for this statement [on the PDF annotated by the reviewer]

R4: The very important study that provided these decline percentages is already cited. Since we are directly referring to this study, adding other references would not strengthen the argument.

C5: Please add the reference or the website link

R5: We added the general link for the IUCN list as well as a Mediterranean infopage rather than a separate link for each of the 24 species of Squatina.  

C6: Please describe the aim of this study clearly in this paragraph [indicated on the PDF]

R6: We thank the reviewer for this wonderful suggestion. The aim of the study I now added at the beginning of the paragrpah.

C7: Italic for “Squatina” and Cm long → cm total length (TL)

R7: These items were corrected as suggested.

C8: In Figure 1 → Please add more information on the map indicating the land, waters, map scale, and direction. Most readers may not be familiar with the Turkish map.

R8: Agreed; the map now includes all the requested information.

C9: Please add the image of the mother or adult S. oculate to show a correct identification for this species. Also, please add scale to the figure

R9: We thank the reviewer for this very helpful comment and have added a photo as suggested of a mature S. oculata female.

C10: Please change the figure to a better-resolution image [and] Add scale on each figure

R10: The images’s resolution was improved and scale bars were added to both figures.

C11: Change “new” to “latest” or “recent”

R12: Agreed; done.

C12: Please indicate all places here on the map in Figure 1

R12: Agreed; all localities named in the text have been added to the map.

C13: Omit the word “New” [and] change “including” to “reported”

R13: Agreed; done.

C14: Change the date to a more standardized format

R14: Agreed; 2005-2008 was changed from 2005 to 2008 (we hope this is the date that was being referred to)

C15: You need to update this information as the ISRAs in the Mediterranean area have already been finalized and mapped in the e-atlas

R15: We thank the reviewer for identifying this error. The sentence has been corrected to read: Using this angel shark data as a basis, along with other records of qualifying endangered species in the region, such as sandbar shark Carcharhinus plumbeus, a new ISRA named the Southeastern Aegean Sea was proposed and accepted in July 2023 , the details of which can be found at https://sharkrayareas.org/portfolio-item/southeastern-aegean-sea-isra/.

C16: Please reword the sentence for better clarity

R16: The sentence in question was rewritten to read: “Both the Mediterranean Action Plan [20,21,64] and Subregional Action Plans for Angelshark Conservation for the Ionian Sea, Aegean Sea and Cyprus- GSAs 21, 22, 23, 24 [66-69] provide detailed guidance towards improving on the angel shark knowledge needed towards helping their populations rebuild.”

C17: I did not see the strong cohesion and cohesiveness of this paragraph to the previous and the later paragraphs.

R17: We thank the reviewer for this very helpful comment. A new subheading was added to the fishing section to better separate those unlinked subjects, i.e., “4.4 Mortality threats from small-scale vs. large-scale fishing”

C18: Change “new record and data” to “updated information” [and] change the font size

R18: Agreed (both points). The font size has been changed to match the MS.

Reviewer 3 Report

Comments and Suggestions for Authors

This study makes an important contribution to knowledge of critically endangered angel sharks in the Mediterranean and is thus a timely and impactful study. The authors have used a complementary set of methods effectively, to reveal new insights into these species’ biology, distribution and vulnerability to threats.

I have provided some specific comments on how the manuscript can be improved below.

Title: There are three angel shark species discussed in the manuscript yet only two are in the title. To make the title more concise I would suggest removing the species names and just saying ‘’three Critically Endangered angel shark species (Squatina)”

Abstract: It would be worth also adding a recommendation about the fishing gears in the abstract, i.e. that angel sharks suffer from higher mortality in trawl gear so areas critical to there life history should be protected from trawling etc

Line 72: It would be necessary to add a reference for this re-evaluation done in 2017.

Line 156-158: This sentence seems to be missing some information as the way it is written currently does not make sense.

Lines 177-181: This paragraph sounds more like a summary of the results, so should be moved to the discussion section.

Table 1: There appears to be a typo for the TL of row 4 in this table. Should it be 67.6 instead of 67,6?

Figure 1: Another map of the broader Mediterranean region should be included here, to provide context to readers not familiar with the area

Lines 389-392: It would be worth adding some discussion here about why the angel sharks may have moved to deeper water. Is this due to increasing temperature, loss of habitat or overfishing?

Lines 411-412. Presumably it is possible that yolk sacs could have become dislodged when hauling the net so this should be acknowledged where the authors make claims about the stage of pups

Lines 418-419: It is possible that one or more pups were already released by the caught angel shark before it was brought onto the fishing vessel, so this should be acknowledged when claiming that the litter size was smaller than reported elsewhere.

Lines 451-461: Here the authors compare the rates of survival in this study, which was largely from set net records, to that of trawling. Generally a higher rate of mortality would be expected during trawling due to crushing injuries and asphyxiation in the net, as oppose to set nets, so this partially explains the difference between the two studies, not just the changing habits of fishers

Line 453: There is a typo on this line “wass”

Lines 456-462: The font appears to be different to the rest of the text here

Lines 466-469: Does the trawler operate in Fethiye bay at the same time as when the angel sharks are likely to be pupping? If so, it would be good to add a recommendation here that the time for trawling is moved to a different season.

Lines 512-515: The font appears to be different here.

The data presented in this study is solely based on fishing records. However, it is possible that these species occur in areas/depths that are not fished, therefore it would be useful to target such areas for scientific surveys, using non-harmful techniques like baited remote underwater video surveys or ROV surveys, to add more information about their distribution. Tagging could also be undertaken to identify critical habitats. It would be worth adding some discussion around these points.  

 

Comments on the Quality of English Language

The English in the manuscript was of a good standard, apart from a few minor typos and grammatical errors I have listed in my comments. 

Author Response

C1: Title: There are three angel shark species discussed in the manuscript yet only two are in the title. To make the title more concise I would suggest removing the species names and just saying ‘’three Critically Endangered angel shark species (Squatina)”

R1: The title was improved upon and now reads: Identifying potential Critical Angel Shark Areas in Türkiye, Eastern Mediterranean based on new records of Squatina spp. identified through fisher engagement

C2: Abstract: It would be worth also adding a recommendation about the fishing gears in the abstract, i.e. that angel sharks suffer from higher mortality in trawl gear so areas critical to there life history should be protected from trawling etc

R2: We thank the reviewer for this comment and the following sentence was added to the abstract (last sentence): This study demonstrates that bottom set nets set by small-scale fishers pose less risk to mortality for angel sharks as they are almost always encountered alive after a usual 12 hour soak time, suggesting that it is bottom trawling in critical habitats which should better regulated (or phased out) to help improve on national angel shark conservation initiatives.

 

C3: Line 72: It would be necessary to add a reference for this re-evaluation done in 2017.

R3: Agreed; we included a new reference for the single species action plan adopted by CMS for Squatina squatina in the Mediterranean which is more relavant and was missed earlier. In 2024, a single species action plan was adopted by CMS for Squatina squatina in the Mediterranean (https://www.cms.int/sites/default/files/document/cms_cop14_doc.27.7.1_ssap-angelshark-med_e.pdf)

C4: Line 156-158: This sentence seems to be missing some information as the way it is written currently does not make sense.

R4: Agreed; the sentence was fixed.

C5: Lines 177-181: This paragraph sounds more like a summary of the results, so should be moved to the discussion section.

R5: Agreed; the paragraph in question was moved to the beginning of the results section.

C6: Table 1: There appears to be a typo for the TL of row 4 in this table. Should it be 67.6 instead of 67,6?

R6: We thank the reviewer for spotting this error, which has now been fixed.

C7: Figure 1: Another map of the broader Mediterranean region should be included here, to provide context to readers not familiar with the area

R7: Agreed; the map was improved and now shows many more details and their Mediterranean context.

C8: Lines 389-392: It would be worth adding some discussion here about why the angel sharks may have moved to deeper water. Is this due to increasing temperature, loss of habitat or overfishing?

R8: We thank the reviewer for this suggestion and have added the following sentence:”Fethiye Bay has suffered from increasing pollution from wastewater from hotels in recent decades which has likely depleted the oxygen content inshallow waters.”

C9: Lines 411-412. Presumably it is possible that yolk sacs could have become dislodged when hauling the net so this should be acknowledged where the authors make claims about the stage of pups

R9: Agreed; we added a sentence here stating this possibility, i.e., “We do not exclude the possibility of other external yolk sacs can become dislodged when hauling in the fishing net.”

C10: Lines 418-419: It is possible that one or more pups were already released by the caught angel shark before it was brought onto the fishing vessel, so this should be acknowledged when claiming that the litter size was smaller than reported elsewhere.

R10: Agreed; we added the following sentence to acknowedge this possibility: “However these pup numbers should be treated conservatively as some pups may have been released while the shark was still in the water.”

C11: Lines 451-461: Here the authors compare the rates of survival in this study, which was largely from set net records, to that of trawling. Generally a higher rate of mortality would be expected during trawling due to crushing injuries and asphyxiation in the net, as oppose to set nets, so this partially explains the difference between the two studies, not just the changing habits of fishers.

R11: This is a very good point and a sentence was added to present this likelihood: “However, it is understood that the retrieval of bottom trawl nets causes more opportunity for the crushing and asphyxiation of species, which also supports the different results in these two studies.”

C12: Line 453: There is a typo on this line “wass”

R12: This has been fixed.

C13: Lines 456-462: The font appears to be different to the rest of the text here

R13: The fints have been fixed.

C14: Does the trawler operate in Fethiye bay at the same time as when the angel sharks are likely to be pupping? If so, it would be good to add a recommendation here that the time for trawling is moved to a different season.

R14: We thank the reviewer for this recomendation. The trawler fishes opportunistically, and the time varies each year however commercial trawling is banned from April 15 until September 1st. Our goal for this project is to ban trawling in Fethiye Bay next year if the government cooperates with us since it is just one or two fishers using the area from outside. I may not be appropriate to present this recomendation just yet, but it may be included will in our subsequent paper, which will map all our angel shark data and users.

Reviewer 4 Report

Comments and Suggestions for Authors

See the file in word attached

Comments for author File: Comments.pdf

Author Response

Please see the attachment.

Author Response File: Author Response.pdf