Marine biodiversity research in the Ryukyu Islands, Japan: Current status and trends
A peer-reviewed article of this Preprint also exists.
Author and article information
Abstract
In Japan, the subtropical Ryukyu Archipelago (RYS; also known as the Nansei Islands) with its coral reefs has been shown to harbor very high levels of marine biodiversity. This study provides an overview of the state of marine biodiversity research in the RYS. First, we examined the amount of scientific literature in the Web of Science (WoS; 1995-2017) on six selected representative taxa spanning from protists to vertebrates across six geographic sub-regions in the RYS. Our results show clear taxonomic and sub-region bias, with research on Pisces, Cnidaria, and Crustacea to be much more common than on Dinoflagellata, Echinodermata, and Mollusca. Such research was more commonly conducted in sub-regions with larger human populations (Okinawa, Yaeyama). Additional analyses with the Ocean Biogeographic Information System (OBIS) records show that within sub-regions, records are concentrated in areas directly around marine research stations and institutes (if present), further showing geographical bias within sub-regions. While not surprising, the results indicate the clear need to study ‘understudied’ taxa in ‘understudied sub-regions’ (Tokara, Miyako, Yakutane, Amami Oshima), and to study ‘understudied areas’ of some sub-regions away from marine research stations. Second, we compared the numbers of scientific papers on eight ecological topics for the RYS with numbers from selected major coral reef regions of the world; the Caribbean (CAB), Great Barrier Reef (GBR), and the Red Sea (RES). Not unexpectedly, the numbers for all topics in the RYS were well below numbers from all other regions, yet within this disparity, research in the RYS on ‘marine protected areas’ and ‘herbivory’ was an order of magnitude lower than numbers in other regions. Additionally, while manuscript numbers on the RYS have increased from 1995 to 2016, the rate of increase (4.0 times) was seen to be lower than those in the CAB, RES, and GBR (4.6 to 8.4 times). As the RYS are considered to contain among the most critically endangered coral reef biodiversity in the world due to high levels of both endemism and anthropogenic threats, much work is urgently needed to address the areas of relative research weakness identified in this study.
Cite this as
2019. Marine biodiversity research in the Ryukyu Islands, Japan: Current status and trends. PeerJ Preprints 7:e27029v2 https://doi.org/10.7287/peerj.preprints.27029v2note This preprint is not peer-reviewed. You may wish to reference the subsequent peer-reviewed version of this article.
Author comment
We have responded to comments from three different reviewers during peer review, following the large majority of their suggestions.
Asides from many minor text changes, the major differences are:
1. The old figure 1 is split into two figures (1, 2) in order to more clearly show the geography, and the differences in literature.
2. A new table (Table 2) charting key research priorities to support marine biodiversity in the RYS.
Sections
Supplemental Information
Example images of the Okinawa sub-region of the RYS within the Ocean Biogeographic Information System (OBIS) for (a) Crustacea, and (b) Dinoflagellata, showing spatial differences in the records of these taxa
Crustacea have most numerous records (n=200-500) in the square that contains Akajima Marine Station. On the other hand, there are almost no data at all for Dinoflagellata. The search was conducted in August 2017.
Search terms for Web of Science and numbers of publications per year (1995-2017) for the Ryukyus, Red Sea, Great Barrier Reef, and Caribbean
Additional Information
Competing Interests
James D. Reimer is an Academic and Section Editor for PeerJ.
Author Contributions
James D Reimer conceived and designed the experiments, performed the experiments, analyzed the data, prepared figures and/or tables, authored or reviewed drafts of the paper, approved the final draft.
Piera Biondi conceived and designed the experiments, performed the experiments, analyzed the data, prepared figures and/or tables, authored or reviewed drafts of the paper, approved the final draft.
Yee Wah Lau conceived and designed the experiments, performed the experiments, analyzed the data, prepared figures and/or tables, authored or reviewed drafts of the paper, approved the final draft.
Giovanni Masucci conceived and designed the experiments, performed the experiments, analyzed the data, prepared figures and/or tables, authored or reviewed drafts of the paper, approved the final draft.
Xuan Hoa Nguyen conceived and designed the experiments, performed the experiments, analyzed the data, prepared figures and/or tables, authored or reviewed drafts of the paper, approved the final draft.
Maria E.A. Santos conceived and designed the experiments, performed the experiments, analyzed the data, prepared figures and/or tables, authored or reviewed drafts of the paper, approved the final draft.
Hin Boo Wee conceived and designed the experiments, performed the experiments, analyzed the data, prepared figures and/or tables, authored or reviewed drafts of the paper, approved the final draft.
Data Deposition
The following information was supplied regarding data availability:
Our raw data are supplied in supplementary file Table S1.
Funding
XHN, MEAS, and HBW were supported by Japanese Government (MEXT) scholarships. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.