May 28, 10:15 (W2-2794)
Current zooplankton production research in India
Ramasamy Santhanam
Fisheries College and Research Institute, Tamilnadu Veterinary and Animal Sciences University,Thoothukudi – 628 008, Tamilnadu, India. E-mail:
The east and west coasts of India are known for their zooplankton. The ongoing research in marine zooplankton of India is primarily basic in nature and applied research is uncommon. In these coastal waters of India, current zooplankton research is mainly on diversity, qualitative and quantitative composition, distribution, diel vertical migration, biochemical composition, and zooplankton-phytoplankton interrelationships. The author has more than 35 years of experience with the marine zooplankton of India and has studied the species composition and biomass of zooplankton in the southeast coast of India. He has also planned applied research on topics such as: bacteria associated with zooplankton; pharmaceutical properties of zooplankton; nutritional characteristics of jellyfish (to serve as human food); zooplankton indicators of sewage and industrial pollution; zooplankton associated with coral reefs; and culture of zooplankton species to serve as live food for aquaculture. The results of current research and methodologies to be followed for future applied zooplankton research will be discussed in detail.
May 28, 10:35 (W2-3426)
Zooplankton in Korean Waters
Young Shil Kang1 and Seok Hyun Youn2
1 West Sea Fisheries Research Institute, Incheon, 400-420. E-mail:
2 East Sea Fisheries Research Institute, Gangrung, 210-800, Korea
We review the results obtained during the past several decades on the spatial and temporal variations of major zooplankton assemblages and biomass, zooplankton indicator species of specific water masses, and decadal changes in zooplankton communities in Korean waters. Additionally, we breifly discuss zooplankton process studies and their importance to fisheries. Copepods were the most dominant group of zooplankton in Korean waters, followed by chaetognaths, siphonophores, euphausiids,, cladocerans, appendicularians and amphipods in order of decrease. Zooplankton biomass showed two peaks in April-June and October with geographical variations, and was higher in the coastal area than in the offshore area. In particular, zooplankton biomass was high in the frontal area compared with the other areas.
Some calanoid copepods were indicator species of oceanic warm-water and were therefore closely associated with the extension of the Tsushima Warm Current. Their distributions indicated that the Tsushima Warm Current occupied the offshore area between Jeju Island and the Korea Strait in February and April and extended to the southern-offshore area of the East/Japan Sea in August and October. Long-term changes in zooplankton biomass and abundance were investigated to understand and predict the impact of climatic change on the marine ecosystem. Zooplankton biomass increased since the early 1990’s and changes in the composition of major zooplankton groups have been observed. Long-term changes in geographic distribution have also been observed.
Studies of zooplankton production and of zooplankton impacts on the fisheries have been very limited in Korean waters. Of coastal neritic calanoid species, egg production and life history of Acartia spp. and Calanus sinicus have been examined. On the other hand, it has been shown that zooplankton biomass and composition affects the squid and mackerel fisheries.Such results clearly suggest future research directions in Korean waters. Especially, we need to understand population level processes on appropriate spatio-temporal scales with focus on understanding productivity. An ecosystem level approach should also be adopted to understand the function of zooplankton in the marine ecosystem. Currently, we are concerned about the abruptly increasing jellyfish populations, changing zooplankton species diversity, and the impact of climatic change on the zooplankton production and composition.
May 28, 10:55 (W2-3658)
Zooplankton research in Indonesian waters
Mulyadi 1 and Inneke F.M. Rumengan 2
1 Zoology Division, Indonesian Institute of Science, Jl. Raya Bogor Km 46, Bogor, Indonesia. E-mail: ,
2 Faculty of Fisheries and Marine Science, Sam Ratulangi Universty, Kampus Unsrat, Manado, Indonesia.
E-mail:
The earliest studies of zooplankton in Indonesian waters, including those from historical expeditions and local faunal studies by individual scientists or research groups, focused primarily on taxonomy. Later, study of fish eggs, larvae and copepods in relation to water properties in the Java Sea was initiated by Delsman (1921–1939). Recent studies by Mulyadi (1994-2006) have listed about 300 species, 55 new records and 11 new species of copepods. Production-oriented studies have also been carried out by several research projects. The influence of monsoonal oceanographic conditions on zooplankton production in the Banda and Arafuru Seas wasinvestigated by cooperative research between Indonesia and the Netherlands during the Snellius II Expeditions (1984–1985). These studies indicated that zooplankton biomass in the east-monsoon (upwelling period) was twice that seen during the west-monsoon (downwelling period). Other cooperative studies such as the Baruna Jaya Expedition I (1964) found higher abundances of zooplankton in the Java Sea than in the Indian Ocean. A similar pattern of temporal zooplankton distribution around the Seribu Islands and in Jakarta Bay has been found by the Research Center for Oceanography. Zooplankton abundance and biomass data (1970-1985), including data from the Snellius II Expeditions, are available in an online database. Studies of zooplankton abundance and diversity in North Sulawesi waters, and pollution issues comparing zooplankton baseline data of 1996 with recent data of 2004 in that region, are also reviewed. Some constraints in taxonomic studies due to a lack of taxonomic skills and poor facilities need to be addressed for future expansion of this zooplankton database.
May 28, 11:30 (W2-3693)
Mesozooplankton in the Sulu Sea and its adjacent waters with special reference to copepods
Jun Nishikawa and Shuhei Nishida
Ocean Research Institute, The University of Tokyo, 1-15-1, Minamidai, Nakano, Tokyo 164-8639, Japan.
E-mail:
The Sulu Sea (SS) is located in the western equatorial Pacific and is a semi-enclosed basin, rimmed by sills shallower than ca. 400 m. This sea has homogeneous and unusually warm (ca. 10 °C) water from the mesopelagic zone to the sea bottom, while the adjacent Celebes Sea and the South China Sea show more ‘normal’ oceanic conditions. Under these contrasting settings, the relationships between vertical water-column structure and biomass, biodiversity and patterns of vertical distribution of mesozooplankton were examined. The total mesozooplankton biomass in the mesopelagic layer, the degree of exponential decrease in their biomass and abundance with depth, the vertical distribution patterns of higher taxonomic groups, and community structure analysis using a dissimilarity index applied to higher taxa, all indicated no significant differences between the seas. This suggests that warm mesopelagic water in the SS does not drastically influence the mesozooplankton standing stocks, vertical distribution patterns and the community structure at the higher taxonomic levels. However, the composition of copepods was markedly different in the calanoid families between the SS and the Celebes Sea, with dominance of Eucalanidae, Metridinidae, and Lucicutiidae in the layer of lower dissolved oxygen in the SS. Reduced abundance in the dominant genera such as Euchaeta, Mormonilla, and Conaea was also observed in the SS. Among the > 300 species identified, 5 possible new species were found only in the mesopelagic water of the SS, suggesting the existence of unique communities at lower taxonomic levels (genera and/or species) in the SS.
May 28, 11:50 (W2-3612)
Experimental study of appendicularians
Riki Sato
Department of Environmental Simulation, Institute for Environmental Sciences, 1-7 Ienomae, Obuchi, Rokkasho, Kamikita, Aomori, 039-3212, Japan. E-mail:
Appendicularians are common pelagic tunicates in the world oceans. This group has received increasing attention because of its significant contribution to the vertical flux of organic matter; their mucus houses are a major origin of marine snow. Appendicularians have a fast growth rate, and a high grazing rate. Most of the ecological studies of appendicularians have been done by marine biologists in European and Northern American countries. In Asian countries, although some excellent work has been done especially on taxonomy and geographical distribution, physiological or ecological studies of appendicularians in this region are still rare.. In this presentation, I will introduce my laboratory and field work on measurements of growth, clearance and house production rates of appendicularians, demonstrate their importance in marine ecosystems of this region, and discuss future work need ed to further understand this unique group of pelagic organisms.
May 28, 12:10 (W2-3399)
Spatial distribution of chaetognaths along with oceanographic conditions off the Northern Bicol Shelf, Philippines (Pacific Coast)
Mary Mar P. Noblezada and Wilfredo L. Campos
Ocean Bio Laboratory, Division of Biological Sciences, College of Arts and Sciences, University of the Philippines in the Visayas, Miagao, Iloilo, Philippines. E-mail:
The composition, abundance and distribution of chaetognaths off the Northern Bicol Shelf, Philippines (Pacific Coast) were analyzed from 31 stations perpendicular to the coast. Samples were collected on board the M/V DA-BFAR from April 1-11, 2001. Corresponding data on the main hydrologic features of the surveyed area were used to relate species occurrence with water masses. Stations grids were laid out to examine the possible heterogeneity in hydrographic conditions. Twenty six species of 5 genera of chaetognaths were identified, and –in order of relative abundance were: Sagitta enflata, S. neglecta, S. serratodentata, S. bipunctata, S. ferox, S. bedoti, S. oceanica, S. robusta, S. minima, S. pacifica, S. decipiens, S. hexaptera, S. johorensis. S. macrocephala, S. regularis, S. tasmanica, S. nagae, Pterosagitta draco, S. pulchra, S. bedfordii, Krohnitta pacifica, K, subtilis, Eukronia fowleri, S. septata, S. setosa, and Spadella sp, excluding the unknown Sagitta sp. and Sagitta juvenile. Sagitta enflata was the most abundant and frequent species in all stations analyzed and comprised 41.88% of the total specimens. Most of the lowest diversity values were distributed in the areas directly affected by or adjacent to upwelling. Highest dominance was observed in station located within the upwelling zones. The occurence of mesopelagic, mesobathypelagic and bathypelagic species (S. decipiens, S. serratodentata, S. macrocephala, S. minima, Krohnitta subtilis, K. pacifica and Eukronia fowleri) in samples collected from the upper layer of water could be explained by vertical transport affected by the upwelling, in which deep-living organisms are carried to the epipelagic layer.
May 28, 2:00 (W2-3286)
Zooplankton community structure in the ports of Mumbai, India: An account since 1940’s.
Chetan A. Gaonkar, Venkat Krishnamurthy and Arga Chandrashekar Anil
Marine Corrosion & Material Research Division, National Institute of Oceanography, Dona Paula, Goa – 403 004, India.
E-mail:
Mumbai is the second largest coastal city in the world and is India’s premier port. The census report of 2001 suggests that the population of Mumbai increased from 4 million in 1960 to 7.7 million in 1971 and is projected to be between 18.3 million and 22.4 million by 2011. This has led to an unprecedented increase in human and industrial activities, resulting in generation of over 2485 million litres of wastewater per day and exerting enormous pressure on the adjacent marine environment, including harbour waters. Nutrient concentrations, especially nitrate, have increased gradually over the years with a simultaneous decrease in dissolved oxygen. Apart from receiving local sewage and industrial waste, the harbour is also subject, by ship ballast water, to inoculation of non-native waters containing a wide range of pollutants and biota.
In order to evaluate the impact of these activities on the surrounding environment and to elucidate the possible changes in the community structure of zooplankton in Mumbai harbour, 14 stations were selected in and around the area and samples were collected during three different periods between 2001 and 2002. The results are compared with the records available from the 1940s. The copepods Canthocalanus sp., Paracalanus nanus, Cosmocalanus sp., Euterpina acutifrons, Nannocalanus minor, Nannocalanus sp. and Tortanus sp. were not reported in the earlier studies but were observed in the present investigation. Purely herbivorous forms like Nannocalanus minor, Paracalanus sp. and Temora discaudata were less abundant during the pre-monsoon sampling, because of reduced diatom concentrations. In contrast, increased abundance of some carnivorous and omnivorous forms during the same period can be related to the changes in food web dynamics. There was also a change in species composition, biomass and abundance between the two post-monsoons. Possible causes for these variations could be the differences in rainfall during the two sampling years. The study area is a tropical mesotrophic environment influenced by southwest monsoons and the two post-monsoon seasons differed with respect to length and intensity of the the preceding monsoons. The anthropogenic contribution to these variations and subsequent responses in ecosystem functioning and food web dynamics are the key issues which will be addressed during this presentation.
May 28, 2:20 (W2-3402)
Long-term variation of trophic status and its impact on the diversity and abundance of zooplankton in Lake Biwa
Chih-hao Hsieh1, Toshiyuki Ishikawa2, Youichirou Sakai1, Kanako Ishikawa2 and Michio Kumagai2
1 Center for Ecological Research, Kyoto University, Hirano 2-509-3, Otsu, 520-2113, Japan. E-mail:
2 Lake Biwa Environmental Research Institute, 5-34 Yanagasaki, Otsu, Shiga 520-0022 Japan
We investigated the trophic status of Lake Biwa and its effects on the diversity and abundance of zooplankton. Lake Biwa, the largest lake of Japan, is one of a few lakes in the world that has undergone eutrophication,due to urbanization, that has later been successfully mitigated. Using time series data from 1962 to 2005, we found that the intensity of eutrophication (based on total phosphorus concentration) in Lake Biwa increased rapidly in the late 1960’s and then decreased in the late 1980’s. Phytoplankton concentration followed the trend of total phosphorus relatively well. The enhanced total phosphorus and thus phytoplankton concentration from the late 60’s to middle 80’s resulted in high abundance of herbivorous zooplankton (e.g. Daphnia and rotifers). =An apparent increased species diversity in zooplankton during this period waslikely due to sampling effects. Curiously, the abundance of carnivorous zooplankton did not follow the same course of eutrophication and mitigation. The fluctuations of carnivorous zooplankton may be affected by both bottom-up (food) and top-down (predators) controls.
May 28, 2:40 (W2-3674)
Succession of zooplankton in the Aral Sea
Iskandar Mirabdullayev1, Lola Abdullayeva1 and Ablatdiyn Musaev2
1 Institute of Zoology, Niyazov str. 1, Tashkent, 100095, Uzbekistan. E-mail:
2 Institute of Bioecology, Berdakh prospect, 41, 742000, Nukus, Uzbekistan