The Coral Reef Preservation and Rehabilitation Project by the Okinawa Prefectural Government, Jap... more The Coral Reef Preservation and Rehabilitation Project by the Okinawa Prefectural Government, Japan, investigated since 2011 the possibility of large-scale reef restoration with asexually derived corals. The research also sought to establish standard methodologies of active coral reef restoration in Okinawa. During three years of consecutive transplantation from 2012 to 2014, about 31,000 non-nursery-farmed and nursery-farmed corals were out-planted, resulting in gradual refinement of the technique. Small coral colonies collected from neighboring natural reefs were raised as donor corals on top of iron poles 50 cm above the seafloor. Fragments taken from those donor corals were subsequently attached to substrata and transplanted to back-reef moats off Onna Village, Okinawa Island (approximately 26°26’50”N, 127°47’40”E). In 2012 and 2013, 15 and 12 acroporid species, respectively, were transplanted without nursery farming. Whereas in 2014, transplantation focused on six species that ...
This is the second part of our paper “Crustaceans on Postage Stamps” (Omori and Holthuis, 2000). ... more This is the second part of our paper “Crustaceans on Postage Stamps” (Omori and Holthuis, 2000). During the period from 1870 to and including / 5 2002, nearly 1468 postage stamps depicting crustaceans have been issued from 218 countries, regions and organizations. In all, 357 taxa were identified at species or genus level. They are classified into 92 families of the classes Branchiopoda, Maxillopoda and Malacostraca. Our checklist of all stamps with crustaceans is added.
This paper begins with a brief overview of the status of coral reefs of Japan and around the worl... more This paper begins with a brief overview of the status of coral reefs of Japan and around the world, followed by a review concerning present research on coral reef rehabilitation at Akajima Marine Science Laboratory in Okinawa, Japan. With respect to the latter, effort has been aimed at developing techniques for the mass culture of Acropora spp. from eggs. Colonies of Acropora tenuis that were reared from eggs and transplanted to the seabed at Akajima began spawning by approximately 20-25 cm in diameter at 4 or 5 years of age. Many fish and crustaceans have inhabited the newly transplanted coral colonies. This demonstrated the possibilities of culturing using sexual propagation as a technique to assist local coral reef rehabilitation and hence, conservation of marine biodiversity. It is humbling and somewhat depressing to compare the small scale of success relative to the wide range of degradation. However, the present method of coral reef rehabilitation has shown enough promise for ...
Abstract In this present study, we investigated the effects of increase and decrease of light int... more Abstract In this present study, we investigated the effects of increase and decrease of light intensity and photoperiods on growth, survival, and photosynthetic efficiency in three different corals, Pocillopora damicornis (Linnaeus, 1758), Acropora millepora (Ehrenberg, 1834) and Platygyra sinensis (Milne Edwards and Haime, 1849) with different ages (6-, 12-, and 24-month old). All experimented corals were cultured from sexual propagation. In light intensity trials, juvenile corals were transferred and exposed to different treatments (0, 21, 42, 85, and 169 μmol m−2 s−1 provided by 400-W metal halide lamps or equal to daily light integrals (DLI) of 0, 0.95, 1.89, 3.8, and 7.6 μmol m−2 s−1) for 2 weeks, while in the photoperiod experiment, the coral colonies were exposed to 5 different treatments (24/0, 18/6, 12/12, 6/18, and 0/24 h light-and-dark cycle). The results from the light intensity experiment showed that 2-year old Platygyra sinensis survived (100%) under all light intensity levels, while the survival rates of other coral species decreased, ranging between 20 and 80%, when the light intensity levels changed from the ambient light condition. For the photoperiod experiments, the results showed that 2-year old Platygyra sinensis and 1-year old Acropora millepora survived (100%) under all photoperiod levels. However, there was no significant difference on the growth of corals between different light intensity levels and different photoperiods. From this study, Platygyra sinensis seemed to have more tolerance to wider ranges of light intensities and photoperiods than other coral species. In addition, the results implied that corals were able to acclimate to a prolonged light period and light intensity, which can be feasible for future coral aquaculture.
The Coral Reef Preservation and Rehabilitation Project by Okinawa Prefectural Government, Japan, ... more The Coral Reef Preservation and Rehabilitation Project by Okinawa Prefectural Government, Japan, attempted to validate the possibility of large-scale reef restoration with asexually-derived corals and to establish refined methodologies of active coral reef restoration in Okinawa. Coral fragments taken from donor corals raised in donor farms were used. During 3-years of consecutive out-plantings from 2012 to 2014, about 30,000 non-nursery-farmed and nursery-farmed corals were out-planted in degraded reefs off the Onna Villege. Various outcomes were obtained through refinement of the reef restoration technique. The present study shows achievement of scientific research and technique based on the work until May 2017. The average annual growth rates of the 15 coral species out-planted in 2012 and 12 species in 2013 were 3.7 cm and 7.5 cm GMD, respectively; the rate out-planted has increased to 12.0 cm GMD for the 6 selected species in 2014. The survival rate of the 2014 out-planted corals was more than 63% at 26 months after. Proper choice of species with respect to the restoration site, size of fragments, and the processes of nursery farming and out-planting are decisive factors for the success of coral out-planting. Genomic DNA analysis of Acropora tenuis indicated that substantial portions of clonal individuals existed in the farmed donor colonies. However, no clonal colonies were found in A. tenuis collected from neighboring waters, suggesting that the propagation of the species mainly takes place sexually in nature. The methodologies flexibly developed in the project comprises the following: 1) farming of donor corals; 2) finding suitable species and locations for out-planting; 3) genomic DNA analysis of donor colonies; 4) farming of seedling colonies; 5) out-planting design to advance fertilization and genetic diversity; and 6) long-term monitoring. Nearly 2,000 Yen (18 US$) per colony was required for the asexually-derived fragment farming, out-planting, and monitoring.
ABSTRACT Coral reef restoration is not the same as forest restoration as its success is not alway... more ABSTRACT Coral reef restoration is not the same as forest restoration as its success is not always guaranteed because of insufficient knowledge of coral biology. The technology of active restoration has a history of only 40 years or less. In spite of many devices and efforts, restoration is often hampered by low survivorship of colonies, fragments or sexual propagules. In order to enhance coral resilience and adaptation in a changing world, many new approaches to coral reef restoration are being suggested. However, we wouldn't be able to succeed or achieve expected result, i.e. recovery and thriving of the coral reefs, if outplanted coral recruits do not grow well and spawn and successfully fertilize in the sea. The cost to restore a few hectares of reef is often considerable. More studies are needed to improve the methodology. Contractors and practitioners of coral reef restoration projects must have advanced techniques supported by strong science for successful propagation, rearing, and transplantation/outplantation of corals. This review describes what we have learned so far from research on active coral reef restoration and discusses seven topics that may facilitate successful restoration projects.
Validity of ceramic coral settlement devices (CSD: Okamoto et al. 2008) was compared with scallop... more Validity of ceramic coral settlement devices (CSD: Okamoto et al. 2008) was compared with scallop shells, ceramic plates, and Coral Net ® in order to assess usefulness of artificial substratum for coral larvae. The results did not corroborate previous reports, saying the CSD to be a strong enhancer of settlement. Although the CSDs have been employed for many coral reef rehabilitation projects in Japan, a reassessment must be necessary. Larval settlement choice is highly dependent on external cues, such as crustose coralline algae and bacteria, but not associated with materials of artificial substratum. Physical characteristics of the substratum aid in fixation of the larvae after settlement. For flat ceramic plate, survival rate of larvae was higher on the vertical surface than the horizontal surface. Existence of hollow or micro-crevice on substratum enhances considerably for survivorship of coral recruits as they can avoid predation and destruction by fish and sea urchin. The best substratum should be effective not only in inducing larval settlement but also in enhancing survivorship of juvenile corals after metamorphosis. Design aspects that increase ease of out-planting operation and ability to withstand physical stresses (i.e. wave action) should also be taken into consideration.
Publications of the Seto Marine Biological Laboratory
In addition, E. matsuei was described by us (Tanaka and Omori, 1967). In the present paper the oc... more In addition, E. matsuei was described by us (Tanaka and Omori, 1967). In the present paper the occurrence of 31 species including 4 new and 2 unidentified species is reported (Table 1). Also a single species of Haloptilus is reported as it was accidentally left out of our previous report (Tanaka and Omori, 1971). In all, 14 species are recorded for the first time in the Additional Calanoid Copepods from lzu Region Part 5 10 (9) 11 (12) Number of setae on lobes of2nd maxilla; 1, 1, 2, 3, 2, 3 ....... E.jiligerus Number of setae on lobes of 2nd maxilla; 3, 2, 2, 3, 2, 3. Genital segment as long as wide. Rostral filaments thick ....... E. squamatus Genital segment 1.5 times as long as wide. Rostral filaments slender.
A description is given of a simple bottom-net designed to collect zooplankton from the immediate ... more A description is given of a simple bottom-net designed to collect zooplankton from the immediate vicinity of the sea-floor. The gear consists of a net, sled, and releasing equipment. The net has 70 cm by 70 cm in opening square and 350 cm long, and is towed on sandy or muddy bottom at a speed of 1.5. to 3.5 knots. Besides a number of new mysids and decapods, some rare crustacea species were collected in Sagami and Suruga Bays. They have hardly been obtained by ordinary plankton tow-nets. An epiplanktonic chaetognath Sagitta nagae was abundant on the sea-floor of 20 m depth in the daytime.
A new species of calanoid copepod, Euchirella tanseii n. sp., is described from the bottom living... more A new species of calanoid copepod, Euchirella tanseii n. sp., is described from the bottom living crustacean collections made by the RV Tansei Maru in Sagami Bay. A female of the specimen was obtained in bottom net hauls taken on a sandy and gravelly substrate at a depth of 100 m. The species closely resembles Euchirella venusta GIESBRECHT and E. pulchra (LUBBOCK), but can be distinguished by shape of the genital segment and the number of setae on 2nd segment of endopodite of 2nd antenna. The comparison of systematical characters with these species is attempted.
The movement of the cold Oyashio water and the occurrence of the cold water mass in Kumanonada we... more The movement of the cold Oyashio water and the occurrence of the cold water mass in Kumanonada were discussed through the distribution of four cold-water copepods, Calanus plumchrus, Calanus cristatus, Eucalanus bungii bungii, and Metridia lucens, in the waters off east-central Honshu. The selected copepods which are known to be most dominantly distributed in the shallow layer of the Oyashio area, north of 40•‹N in general, were found in the present area in the depths greater than 400 m where the temperature was lower than 10•‹C. Their distribution seemed to agree with the layers where the Pacific Intermediate Water exists. Great differences were observed between C. cristatus obtained in the present area and that from the Oyashio area on comparing their composition of developmental stages, population, and body weight. These facts indicated that the reproduction of the cold-water copepods does not occur in the present area but they are only supplied from the Oyashio area. It is evident from their distribution pattern that the Oyashio water sinks and spreads widely to southward at the levels between 400 m and 1,000 m, and furthermore it extends westerly as far west as about 138•‹E after passing over the Izu ridge. Probably, the water finally reaches Kumanonada. There might exist two branches of the submerged Oyashio water. One flows along the coast of Honshu, north of the Kuroshio, and the other runs in offshore area, south of the Kuroshio. The appearance of the copepods suggested that the former retains the characteristics of the Oyashio water rather than the latter.
Planktology in Japan celebrates 100 years of history since the term "Plankton" had first been tra... more Planktology in Japan celebrates 100 years of history since the term "Plankton" had first been translated into Japanese "Fuyuseibutsu" by K. Okamura in 1900. It was initially taught at three fisheries-related governmental institutions. As the fisheries industry was of great importance to Japan, marine planktology gathered considerable interest from the beginning. The era of moderniza tion of plankton research in Japan was in the 1960s. In the 1970s, environmental problems came to the fore and achievements were made concerning the red tides and relationship between plankton and shellfish poisoning. Although there was an unfortunate split between the field of planktology and fisheries science, Japan's plankton research attracts intense interest from scientists around the world, especially concerning fisheries-related subjects such as red tides, mass production of micro-organ isms for aquaculture, and resource management with cooperation between fishermen and scientists. Marine planktologists once again have to redefine their role in the dissemination of knowledge and information for the benefit of the fisheries industry, environmental protection, and resource manage ment. It is hoped to have many more planktologists with broad knowledge and interests to develop a holistic picture of biological processes and production in the ocean.
It was 1899 when a red-tide at the head of Suruga Bay was reported and its forming agent identifi... more It was 1899 when a red-tide at the head of Suruga Bay was reported and its forming agent identified as Noctiluca by T. Nishikawa. In the year following this, the first scientific report on plankton in Japan, the terms" plankton" and" planktology" were translated into Japanese ...
Publications of the Seto Marine Biological Laboratory, Nov 29, 1969
With 5 Text-figures Following the previous report on Euchaeta and Pareuchaeta (TANAKA and OMORI, ... more With 5 Text-figures Following the previous report on Euchaeta and Pareuchaeta (TANAKA and OMORI, 1968), the present paper deals with Euchirella and Pseudochirella in the lzu region. The sampling method, position, depth, and date are given in the above cited paper. Regarding Euchirella from the Pacific and Indian Oceans, the authors confirmed previously the existance of 15 species including E. tanseii (TANAKA and OMORI, 1969).
PROCEEDINGS OF CIVIL ENGINEERING IN THE OCEAN, 2003
In the first of a series of experiments on coral recruitment by in situ mass culture, transportat... more In the first of a series of experiments on coral recruitment by in situ mass culture, transportation, and settlement of reef-building coral larvae in Okinawa, Japan, gametes and embryos from slick on the sea surface after mass spawning in early summer, 2002 were collected and cultured in eight floating culture ponds(2.0mL x 2.0mW x 1.0mD each) at Akajima until the planula larvae were competent to settle into the substratum. In May, about 2 million larvae were transported by boat to a seeding experimental station at Naha Port, a distance of 50 km east of Akajima. Similarly, in June additional 1.2 million larvae cultured in a 1-ton rearing tank were transported to the same seeding station. Divers then released the larvae over concrete blocks surrounded by a vinyl cloth with windows in a mesh screen or by a nylon mesh enclosure. The number of polyps settled on the concrete blocks was monitored 4, 7 and 9 months after seeding and compared with a control outside the mesh enclosures. The results exhibited an enhancement of coral larval recruitment and demonstrated the applicability of this restoration technology in the rehabilitation of coral reefs in defined areas where natural recruitment is limited.
The Coral Reef Preservation and Rehabilitation Project by the Okinawa Prefectural Government, Jap... more The Coral Reef Preservation and Rehabilitation Project by the Okinawa Prefectural Government, Japan, investigated since 2011 the possibility of large-scale reef restoration with asexually derived corals. The research also sought to establish standard methodologies of active coral reef restoration in Okinawa. During three years of consecutive transplantation from 2012 to 2014, about 31,000 non-nursery-farmed and nursery-farmed corals were out-planted, resulting in gradual refinement of the technique. Small coral colonies collected from neighboring natural reefs were raised as donor corals on top of iron poles 50 cm above the seafloor. Fragments taken from those donor corals were subsequently attached to substrata and transplanted to back-reef moats off Onna Village, Okinawa Island (approximately 26°26’50”N, 127°47’40”E). In 2012 and 2013, 15 and 12 acroporid species, respectively, were transplanted without nursery farming. Whereas in 2014, transplantation focused on six species that ...
This is the second part of our paper “Crustaceans on Postage Stamps” (Omori and Holthuis, 2000). ... more This is the second part of our paper “Crustaceans on Postage Stamps” (Omori and Holthuis, 2000). During the period from 1870 to and including / 5 2002, nearly 1468 postage stamps depicting crustaceans have been issued from 218 countries, regions and organizations. In all, 357 taxa were identified at species or genus level. They are classified into 92 families of the classes Branchiopoda, Maxillopoda and Malacostraca. Our checklist of all stamps with crustaceans is added.
This paper begins with a brief overview of the status of coral reefs of Japan and around the worl... more This paper begins with a brief overview of the status of coral reefs of Japan and around the world, followed by a review concerning present research on coral reef rehabilitation at Akajima Marine Science Laboratory in Okinawa, Japan. With respect to the latter, effort has been aimed at developing techniques for the mass culture of Acropora spp. from eggs. Colonies of Acropora tenuis that were reared from eggs and transplanted to the seabed at Akajima began spawning by approximately 20-25 cm in diameter at 4 or 5 years of age. Many fish and crustaceans have inhabited the newly transplanted coral colonies. This demonstrated the possibilities of culturing using sexual propagation as a technique to assist local coral reef rehabilitation and hence, conservation of marine biodiversity. It is humbling and somewhat depressing to compare the small scale of success relative to the wide range of degradation. However, the present method of coral reef rehabilitation has shown enough promise for ...
Abstract In this present study, we investigated the effects of increase and decrease of light int... more Abstract In this present study, we investigated the effects of increase and decrease of light intensity and photoperiods on growth, survival, and photosynthetic efficiency in three different corals, Pocillopora damicornis (Linnaeus, 1758), Acropora millepora (Ehrenberg, 1834) and Platygyra sinensis (Milne Edwards and Haime, 1849) with different ages (6-, 12-, and 24-month old). All experimented corals were cultured from sexual propagation. In light intensity trials, juvenile corals were transferred and exposed to different treatments (0, 21, 42, 85, and 169 μmol m−2 s−1 provided by 400-W metal halide lamps or equal to daily light integrals (DLI) of 0, 0.95, 1.89, 3.8, and 7.6 μmol m−2 s−1) for 2 weeks, while in the photoperiod experiment, the coral colonies were exposed to 5 different treatments (24/0, 18/6, 12/12, 6/18, and 0/24 h light-and-dark cycle). The results from the light intensity experiment showed that 2-year old Platygyra sinensis survived (100%) under all light intensity levels, while the survival rates of other coral species decreased, ranging between 20 and 80%, when the light intensity levels changed from the ambient light condition. For the photoperiod experiments, the results showed that 2-year old Platygyra sinensis and 1-year old Acropora millepora survived (100%) under all photoperiod levels. However, there was no significant difference on the growth of corals between different light intensity levels and different photoperiods. From this study, Platygyra sinensis seemed to have more tolerance to wider ranges of light intensities and photoperiods than other coral species. In addition, the results implied that corals were able to acclimate to a prolonged light period and light intensity, which can be feasible for future coral aquaculture.
The Coral Reef Preservation and Rehabilitation Project by Okinawa Prefectural Government, Japan, ... more The Coral Reef Preservation and Rehabilitation Project by Okinawa Prefectural Government, Japan, attempted to validate the possibility of large-scale reef restoration with asexually-derived corals and to establish refined methodologies of active coral reef restoration in Okinawa. Coral fragments taken from donor corals raised in donor farms were used. During 3-years of consecutive out-plantings from 2012 to 2014, about 30,000 non-nursery-farmed and nursery-farmed corals were out-planted in degraded reefs off the Onna Villege. Various outcomes were obtained through refinement of the reef restoration technique. The present study shows achievement of scientific research and technique based on the work until May 2017. The average annual growth rates of the 15 coral species out-planted in 2012 and 12 species in 2013 were 3.7 cm and 7.5 cm GMD, respectively; the rate out-planted has increased to 12.0 cm GMD for the 6 selected species in 2014. The survival rate of the 2014 out-planted corals was more than 63% at 26 months after. Proper choice of species with respect to the restoration site, size of fragments, and the processes of nursery farming and out-planting are decisive factors for the success of coral out-planting. Genomic DNA analysis of Acropora tenuis indicated that substantial portions of clonal individuals existed in the farmed donor colonies. However, no clonal colonies were found in A. tenuis collected from neighboring waters, suggesting that the propagation of the species mainly takes place sexually in nature. The methodologies flexibly developed in the project comprises the following: 1) farming of donor corals; 2) finding suitable species and locations for out-planting; 3) genomic DNA analysis of donor colonies; 4) farming of seedling colonies; 5) out-planting design to advance fertilization and genetic diversity; and 6) long-term monitoring. Nearly 2,000 Yen (18 US$) per colony was required for the asexually-derived fragment farming, out-planting, and monitoring.
ABSTRACT Coral reef restoration is not the same as forest restoration as its success is not alway... more ABSTRACT Coral reef restoration is not the same as forest restoration as its success is not always guaranteed because of insufficient knowledge of coral biology. The technology of active restoration has a history of only 40 years or less. In spite of many devices and efforts, restoration is often hampered by low survivorship of colonies, fragments or sexual propagules. In order to enhance coral resilience and adaptation in a changing world, many new approaches to coral reef restoration are being suggested. However, we wouldn't be able to succeed or achieve expected result, i.e. recovery and thriving of the coral reefs, if outplanted coral recruits do not grow well and spawn and successfully fertilize in the sea. The cost to restore a few hectares of reef is often considerable. More studies are needed to improve the methodology. Contractors and practitioners of coral reef restoration projects must have advanced techniques supported by strong science for successful propagation, rearing, and transplantation/outplantation of corals. This review describes what we have learned so far from research on active coral reef restoration and discusses seven topics that may facilitate successful restoration projects.
Validity of ceramic coral settlement devices (CSD: Okamoto et al. 2008) was compared with scallop... more Validity of ceramic coral settlement devices (CSD: Okamoto et al. 2008) was compared with scallop shells, ceramic plates, and Coral Net ® in order to assess usefulness of artificial substratum for coral larvae. The results did not corroborate previous reports, saying the CSD to be a strong enhancer of settlement. Although the CSDs have been employed for many coral reef rehabilitation projects in Japan, a reassessment must be necessary. Larval settlement choice is highly dependent on external cues, such as crustose coralline algae and bacteria, but not associated with materials of artificial substratum. Physical characteristics of the substratum aid in fixation of the larvae after settlement. For flat ceramic plate, survival rate of larvae was higher on the vertical surface than the horizontal surface. Existence of hollow or micro-crevice on substratum enhances considerably for survivorship of coral recruits as they can avoid predation and destruction by fish and sea urchin. The best substratum should be effective not only in inducing larval settlement but also in enhancing survivorship of juvenile corals after metamorphosis. Design aspects that increase ease of out-planting operation and ability to withstand physical stresses (i.e. wave action) should also be taken into consideration.
Publications of the Seto Marine Biological Laboratory
In addition, E. matsuei was described by us (Tanaka and Omori, 1967). In the present paper the oc... more In addition, E. matsuei was described by us (Tanaka and Omori, 1967). In the present paper the occurrence of 31 species including 4 new and 2 unidentified species is reported (Table 1). Also a single species of Haloptilus is reported as it was accidentally left out of our previous report (Tanaka and Omori, 1971). In all, 14 species are recorded for the first time in the Additional Calanoid Copepods from lzu Region Part 5 10 (9) 11 (12) Number of setae on lobes of2nd maxilla; 1, 1, 2, 3, 2, 3 ....... E.jiligerus Number of setae on lobes of 2nd maxilla; 3, 2, 2, 3, 2, 3. Genital segment as long as wide. Rostral filaments thick ....... E. squamatus Genital segment 1.5 times as long as wide. Rostral filaments slender.
A description is given of a simple bottom-net designed to collect zooplankton from the immediate ... more A description is given of a simple bottom-net designed to collect zooplankton from the immediate vicinity of the sea-floor. The gear consists of a net, sled, and releasing equipment. The net has 70 cm by 70 cm in opening square and 350 cm long, and is towed on sandy or muddy bottom at a speed of 1.5. to 3.5 knots. Besides a number of new mysids and decapods, some rare crustacea species were collected in Sagami and Suruga Bays. They have hardly been obtained by ordinary plankton tow-nets. An epiplanktonic chaetognath Sagitta nagae was abundant on the sea-floor of 20 m depth in the daytime.
A new species of calanoid copepod, Euchirella tanseii n. sp., is described from the bottom living... more A new species of calanoid copepod, Euchirella tanseii n. sp., is described from the bottom living crustacean collections made by the RV Tansei Maru in Sagami Bay. A female of the specimen was obtained in bottom net hauls taken on a sandy and gravelly substrate at a depth of 100 m. The species closely resembles Euchirella venusta GIESBRECHT and E. pulchra (LUBBOCK), but can be distinguished by shape of the genital segment and the number of setae on 2nd segment of endopodite of 2nd antenna. The comparison of systematical characters with these species is attempted.
The movement of the cold Oyashio water and the occurrence of the cold water mass in Kumanonada we... more The movement of the cold Oyashio water and the occurrence of the cold water mass in Kumanonada were discussed through the distribution of four cold-water copepods, Calanus plumchrus, Calanus cristatus, Eucalanus bungii bungii, and Metridia lucens, in the waters off east-central Honshu. The selected copepods which are known to be most dominantly distributed in the shallow layer of the Oyashio area, north of 40•‹N in general, were found in the present area in the depths greater than 400 m where the temperature was lower than 10•‹C. Their distribution seemed to agree with the layers where the Pacific Intermediate Water exists. Great differences were observed between C. cristatus obtained in the present area and that from the Oyashio area on comparing their composition of developmental stages, population, and body weight. These facts indicated that the reproduction of the cold-water copepods does not occur in the present area but they are only supplied from the Oyashio area. It is evident from their distribution pattern that the Oyashio water sinks and spreads widely to southward at the levels between 400 m and 1,000 m, and furthermore it extends westerly as far west as about 138•‹E after passing over the Izu ridge. Probably, the water finally reaches Kumanonada. There might exist two branches of the submerged Oyashio water. One flows along the coast of Honshu, north of the Kuroshio, and the other runs in offshore area, south of the Kuroshio. The appearance of the copepods suggested that the former retains the characteristics of the Oyashio water rather than the latter.
Planktology in Japan celebrates 100 years of history since the term "Plankton" had first been tra... more Planktology in Japan celebrates 100 years of history since the term "Plankton" had first been translated into Japanese "Fuyuseibutsu" by K. Okamura in 1900. It was initially taught at three fisheries-related governmental institutions. As the fisheries industry was of great importance to Japan, marine planktology gathered considerable interest from the beginning. The era of moderniza tion of plankton research in Japan was in the 1960s. In the 1970s, environmental problems came to the fore and achievements were made concerning the red tides and relationship between plankton and shellfish poisoning. Although there was an unfortunate split between the field of planktology and fisheries science, Japan's plankton research attracts intense interest from scientists around the world, especially concerning fisheries-related subjects such as red tides, mass production of micro-organ isms for aquaculture, and resource management with cooperation between fishermen and scientists. Marine planktologists once again have to redefine their role in the dissemination of knowledge and information for the benefit of the fisheries industry, environmental protection, and resource manage ment. It is hoped to have many more planktologists with broad knowledge and interests to develop a holistic picture of biological processes and production in the ocean.
It was 1899 when a red-tide at the head of Suruga Bay was reported and its forming agent identifi... more It was 1899 when a red-tide at the head of Suruga Bay was reported and its forming agent identified as Noctiluca by T. Nishikawa. In the year following this, the first scientific report on plankton in Japan, the terms" plankton" and" planktology" were translated into Japanese ...
Publications of the Seto Marine Biological Laboratory, Nov 29, 1969
With 5 Text-figures Following the previous report on Euchaeta and Pareuchaeta (TANAKA and OMORI, ... more With 5 Text-figures Following the previous report on Euchaeta and Pareuchaeta (TANAKA and OMORI, 1968), the present paper deals with Euchirella and Pseudochirella in the lzu region. The sampling method, position, depth, and date are given in the above cited paper. Regarding Euchirella from the Pacific and Indian Oceans, the authors confirmed previously the existance of 15 species including E. tanseii (TANAKA and OMORI, 1969).
PROCEEDINGS OF CIVIL ENGINEERING IN THE OCEAN, 2003
In the first of a series of experiments on coral recruitment by in situ mass culture, transportat... more In the first of a series of experiments on coral recruitment by in situ mass culture, transportation, and settlement of reef-building coral larvae in Okinawa, Japan, gametes and embryos from slick on the sea surface after mass spawning in early summer, 2002 were collected and cultured in eight floating culture ponds(2.0mL x 2.0mW x 1.0mD each) at Akajima until the planula larvae were competent to settle into the substratum. In May, about 2 million larvae were transported by boat to a seeding experimental station at Naha Port, a distance of 50 km east of Akajima. Similarly, in June additional 1.2 million larvae cultured in a 1-ton rearing tank were transported to the same seeding station. Divers then released the larvae over concrete blocks surrounded by a vinyl cloth with windows in a mesh screen or by a nylon mesh enclosure. The number of polyps settled on the concrete blocks was monitored 4, 7 and 9 months after seeding and compared with a control outside the mesh enclosures. The results exhibited an enhancement of coral larval recruitment and demonstrated the applicability of this restoration technology in the rehabilitation of coral reefs in defined areas where natural recruitment is limited.
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Papers by Makoto Omori