Papers - FUKAMI Hironobu
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Mizuno K., Terayama K., Hagino S., Tabeta S., Sakamoto S., Ogawa T., Sugimoto K., Fukami H.
Scientific Reports 10 ( 1 ) 12416 2020.12
Language：English Publishing type：Research paper (scientific journal) Publisher：Scientific Reports
© 2020, The Author(s). Over the last 3 decades, a large portion of coral cover has been lost around the globe. This significant decline necessitates a rapid assessment of coral reef health to enable more effective management. In this paper, we propose an efficient method for coral cover estimation and demonstrate its viability. A large-scale 3-D structure model, with resolutions in the x, y and z planes of 0.01 m, was successfully generated by means of a towed optical camera array system (Speedy Sea Scanner). The survey efficiency attained was 12,146 m2/h. In addition, we propose a segmentation method utilizing U-Net architecture and estimate coral coverage using a large-scale 2-D image. The U-Net-based segmentation method has shown higher accuracy than pixelwise CNN modeling. Moreover, the computational cost of a U-Net-based method is much lower than that of a pixelwise CNN-based one. We believe that an array of these survey tools can contribute to the rapid assessment of coral reefs.
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Differences in spawning time drive cryptic speciation in the coral Acropora divaricata Reviewed
Furukawa M., Ohki S., Kitanobo S., Fukami H., Morita M.
Marine Biology 167 ( 11 ) 2020.11
Language：English Publishing type：Research paper (scientific journal) Publisher：Marine Biology
Most of the reef-building Acropora corals around Okinawa Island spawn in May and/or June. We found that two morphotypes of Acropora divaricata spawned in August and/or September. The “robust” and “slender” morphotypes differed in branch width and in the diameter of axial corallites. Histological analyses showed that the onset of gamete production/maturation occurred from June onwards. Most of the other Acropora species spawned from late May to early June. A. florida, which spawned in May/June, initiated gamete production in early April. We assumed that the two morphotypes of A. divaricata were reproductively isolated from most of the other Acropora species because of differences in the spawning seasons. We found that the spawning seasons of the two morphotypes slightly overlapped in 2015 but not in 2019, and inter-morphotype gamete compatibility was high. However, population genetics analyses and a phylogeny of the mitochondrial d-loop region showed that they were genetically distinct and rarely hybridized. Thus, the broadcast-spawning coral A. divaricata might have speciated when there might have been only a low possibility of interspecific gamete interaction.
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Mizuno K., Terayama K., Tabeta S., Sakamoto S., Matsumoto Y., Sugimoto Y., Ogawa T., Sugimoto K., Fukami H., Sakagami M., Deki M., Kawakubo A.
IEEE Journal of Oceanic Engineering 45 ( 4 ) 1386 - 1395 2020.10
Language：English Publishing type：Research paper (scientific journal) Publisher：IEEE Journal of Oceanic Engineering
Various methods have been developed and used for monitoring marine benthic habitats, such as coral reefs and seagrass meadows. However, the efficiency of general survey methods [e.g., line intercept transects and autonomous underwater vehicles (AUVs)] still is not high. In this article, we propose a practical coral-coverage estimation method combining an effective survey system [Speedy Sea Scanner (SSS)] and a deep-learning-based estimation method. The SSS is a towed-type system with six cameras arrayed on the platform. The depth rating of the system in our trial was 50 m. The length of the array baseline was 4.4 m, and six cameras were placed on the platform with equal spacing. The sea trial was conducted at Kujuku-Shima, Japan, on September 30, 2017. We successfully generated 3-D models and high-quality orthophotos of the seafloor with high resolution of about 1.5 mm/pixel. The survey efficiency of the SSS was about 7000 m2/h. In addition, the experimental results of coral-coverage estimation showed that the corals can be distinguished with accuracy of about 80% in places with relatively high transparency, and the error of coverage estimation was 10% or less. The proposed coral-coverage estimation method is more efficient than other survey techniques and costs less than AUV surveying; therefore, it is expected to become a promising tool for marine environmental surveying.
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Oku Y., Iwao K., Hoeksema B.W., Dewa N., Tachikawa H., Koido T., Fukami H.
Contributions to Zoology 89 ( 2 ) 188 - 209 2020.3
Language：English Publishing type：Research paper (scientific journal) Publisher：Contributions to Zoology
© 2020 Brill Academic Publishers. All rights reserved. Recent molecular phylogenetic analyses of scleractinian corals have resulted in the discovery of cryptic lineages. To understand species diversity in corals, these lineages need to be taxonomically defined. In the present study, we report the discovery of a distinct lineage obscured by the traditional morphological variation of Fungia fungites. This taxon exists as two distinct morphs: Attached and unattached. Molecular phylogenetic analyses using mitochondrial COI and nuclear ITS markers as well as morphological comparisons were performed to clarify their phylogenetic relationships and taxonomic positions. Molecular data revealed that F. fungites consists of two genetically distinct clades (A and B). Clade A is sister to a lineage including Danafungia scruposa and Halomitra pileus, while clade B formed an independent lineage genetically distant from these three species. The two morphs were also found to be included in both clades, although the attached morph was predominantly found in clade A. Morphologically, both clades were statistically different in density of septal dentation, septal number, and septal teeth shape. These results indicate that F. fungites as presently recognized is actually a species complex including at least two species. After checking type specimens, we conclude that specimens in clade A represent true F. fungites with two morphs (unattached and attached) and that all of those in clade B represent an unknown species and genus comprising an unattached morph with only one exception. These findings suggest that more unrecognized taxa with hitherto unnoticed morphological differences can be present among scleractinian corals.
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Morita M., Kitanobo S., Nozu R., Iwao K., Fukami H., Isomura N.
Coral Reefs 38 ( 6 ) 1211 - 1223 2019.12
Language：English Publishing type：Research paper (scientific journal) Publisher：Coral Reefs
© 2019, Springer-Verlag GmbH Germany, part of Springer Nature. Although many sympatric species of the coral Acropora spawns on the same day, hybridization is partly prevented by their species-specific fertilization manner. On the other hand, several species show bidirectional intercrossing, but their hybridization is prevented by slight time differences in their spawning and fertilization preference with conspecific sperm. However, it is scarcely described how the intercrossing species avoid hybridization. Here we demonstrate that hybridization of the intercrossing species Acropora tenuis and A. donei is likely prevented by differences in the timing of spawning, gametogenesis (differences in production numbers of matured sperm and eggs), population density, and fertilization preferences. We investigated three locations in Okinawa, Japan: Aka Island, Sesoko Island, and Oku. The timing of gamete release in the two species overlapped at Aka Island and Oku, but A. donei did not spawn vigorously at Sesoko Island. Histological observations indicated a decrease in the number of mature sperm and eggs in the weakly spawning colonies of A. donei at Sesoko Island. From the population density, as assessed by field surveys, we predicted that the encounter rate with heterospecific gametes for A. donei around Sesoko Island was higher than at the other locations. Thus, one predictable reason for the suppression of their gonadal development may be the avoidance of hybridization. Although synchronous spawning of A. tenuis and A. donei was observed at Aka Island and Oku, hybridization is likely infrequent, because sperm choice experiments demonstrated that the eggs preferred fertilization by conspecific sperm. Moreover, microsatellite analyses suggested that hybridization rarely occurred even at synchronous spawning sites, as the population structures of the two species at both Aka Island and Oku were not mixed. Collectively, the findings of this study highlight several strategies, tactics, and mechanisms of avoiding hybridization that are likely to be active in other species that hybridize in vitro.
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宮崎県日南海岸におけるサンゴ捕食動物によるサンゴの被害とその駆除活動（2011～ 2018年）について
深見 裕伸, 安田 仁奈, 福田 道喜, 秋田 優, 日南海岸サンゴ群集保全協議会
宮崎の自然と環境 ( 4 ) 46 - 51 2019.12
Language：Japanese Publishing type：Research paper (scientific journal)
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Koido T, Imahara Y, Fukami H
ZooKeys 862 1 - 22 2019.7
Language：English Publishing type：Research paper (scientific journal)
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Maternal inheritance of F1 hybrid morphology and colony shape in the coral genus Acropora Reviewed
Fukami H, Iwao K, Kumagai NH, Morita M, Isomura N
PeerJ 7 e6429 2019.2
Language：English Publishing type：Research paper (scientific journal)
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Mizuno K., Tabeta S., Matsumoto Y., Sakamoto S., Sugimoto Y., Ogawa T., Sugimoto K., Jimenez L., Terayama K., Fukami H., Sakagami M., Deki M., Kawakubo A.
2018 OCEANS - MTS/IEEE Kobe Techno-Oceans, OCEANS - Kobe 2018 2018.12
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：2018 OCEANS - MTS/IEEE Kobe Techno-Oceans, OCEANS - Kobe 2018
© 2018 IEEE Various methods have been developed and used for monitoring marine benthic habitats, such as coral reefs and seagrass meadows. Basically, field transects, such as Line Intercept Transect (LIT), Photo Line Intercept Transect (PLIT), and Video Transect (VT), are the most widely used methods as it is easy and simple to conduct as well as less costly 1. However, these in-situ visual method requires long sampling time due to the small coverage of the methods. In addition, 3D information of the seabed cannot be obtained. On the other hand, marine biologists and ecologists have increasingly relied on imagery from platforms such as autonomous underwater vehicles (AUVs) for marine monitoring 2, 3. The underwater imagery obtained by AUVs can be used to make high quality 3D model of seabed, classify and count the abundance of various species in an area. However, the cost for development is still high and expert is necessary for the operation of vehicles. In addition, the AUV systems usually use mono or stereo cameras for the observation, therefore, the coverage of the observation is not wide
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Morpho-Molecular Evidence for Polymorphism in the Mushroom Coral Cycloseris hexagonalis (Scleractinia: Fungiidae), with a New Phylogenetic Position and the Establishment of a New Genus for the Species Reviewed
Oku, Y., Naruse, T., Fukami, H.
Zoological Science 34 ( 3 ) 242 - 251 2017.6
Language：English Publishing type：Research paper (scientific journal)
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Loss and Gain of Group I Introns in the Mitochondrial Cox1 Gene of the Scleractinia (Cnidaria; Anthozoa). Reviewed
Chuang, Y., Kitahara, M., Fukami, H., Tracey, D., Miller, D. J., Chen, C. A.
Zoological Studies 56 ( 9 ) 2017.4
Language：English Publishing type：Research paper (scientific journal)
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放卵精型のサンゴにおける受精（２）－ミドリイシ属サンゴを中心に－ Invited
北乃坊誠也, 磯村尚子, 深見裕伸, 守田昌也
みどりいし ( 28 ) 7 - 13 2017.3
Language：Japanese Publishing type：Research paper (bulletin of university, research institution)
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阿嘉島でのサンゴの交配実験 Invited
深見裕伸
みどりいし ( 28 ) 1 - 6 2017.3
Language：Japanese Publishing type：Research paper (bulletin of university, research institution)
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<i>Drupella</i> outbreak in a large coral community off the coast of Cape Toi, Miyazaki, Japan
KOIDO Tatsuki, OKU Yutaro, FUKUDA Michiyoshi, NAKANO Ayami, FUKAMI Hironobu
Galaxea, Journal of Coral Reef Studies 19 ( 1 ) 31 - 32 2017
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：日本サンゴ礁学会
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Taxonomic classification of the reef coral family Lobophylliidae (Cnidaria: Anthozoa: Scleractinia). Reviewed
Huang D, Arrigoni R, Benzoni F, Fukami H, Knowlton N, Smith ND, Stolarski J, Chou LM, Budd AF
Zoological Journal of the Linnean Society 178 436 - 481 2016.10
Language：English Publishing type：Research paper (scientific journal)
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Spawning and fertility of F<inf>1</inf>hybrids of the coral genus Acropora in the Indo-Pacific
Isomura N., Iwao K., Morita M., Fukami H.
Coral Reefs 35 ( 3 ) 851 - 855 2016.9
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Coral Reefs
� 2016, Springer-Verlag Berlin Heidelberg. The role of hybridization through multi-specific synchronous spawning in the evolution of reef-building corals has been discussed since the 1990s, particularly for the genus Acropora. However, F1hybrids have been reported as common in only one case in the Caribbean, with no evidence of mechanisms that would allow continuous reproduction of the hybrids. In this study, we report for the first time the fecundity of two F1hybrid colonies produced experimentally from two Indo-Pacific species, A. intermedia and A. florida. These F1hybrids spawned at the same time as the parental corals. Backcrossing and F1hybrid crossing were successful in both directions. Furthermore, more than 90% self-fertilization was achieved in an F1hybrid, although it was negligible in the parental corals. While it is possible that the F1hybrid was a chimera, these results suggest that some products of interspecific hybridization may persist as the offspring of self-fertilizing F1hybrids.
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The reef building coral Acropora conditionally hybridize under sperm limitation. Reviewed
Kitanobo S, Isomura N, Fukami H, Iwao K, Morita M
Biology Letters 2016.8
Language：English Publishing type：Research paper (scientific journal)
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Genetic evidence of peripheral isolation and low diversity in marginal populations of the Acropora hyacinthus complex. Reviewed
Suzuki G, Keshavmurthy S, Hayashibara T, Wallace CC, Shirayama Y, Chen CA, Fukami H
Coral Reefs 35 1419 - 1432 2016.6
Language：English Publishing type：Research paper (scientific journal)
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When forms meet genes: revision of the scleractinian genera Micromussa and Homophyllia (Lobophylliidae) with a description of twonew species and one new genus. Reviewed
Arrigoni R, Benzoni F, Huang D, Fukami H, Chen CA, Berumen ML, Hoogenboom M, Thomson D, Hoeksema B, Zayasu Y, Budd AF, Terraneo TI, Kinota YF, Baird AH
Contributions to Zoology 85 ( 4 ) 2016.6
Language：English Publishing type：Research paper (scientific journal)
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Outbreak of white syndrome in Acropora spp., temperate region of Japan. Reviewed
Yamashiro H, Fukuda M, Fukami H
Marine Biodiversity 46 321 - 322 2016.6
Language：English Publishing type：Research paper (scientific journal)