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Gladstone William - One of the best experts on this subject based on the ideXlab platform.
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Habitat-mediated use of space by juvenile and mating adult Port Jackson sharks, Heterodontus portusjacksoni, in Eastern Australia
University of Hawaii Press, 2009Co-Authors: Powter, David Mark, Gladstone WilliamAbstract:Studies of spatial ecology of demersal sharks are critical to understanding the significance of habitat variation; however, limited information exists. Spatial ecology of adult Heterodontus portusjacksoni was studied at three locations on the central and southern coast of New South Wales, Australia, from January 2002 to December 2005. Juveniles within a nursery area were studied from December 2002 to December 2005. Tag-recapture, day and night underwater visual census, and acoustic tagging were used. Adults returned annually to the same coastal breeding reefs for up to four consecutive years. Individual juveniles resided within a Sea-Grass nursery area for at least 2 yr and were not uniformly distributed throughout the nursery. Adult females often sheltered in aggregations in gutters as a male avoidance strategy, and both sexes utilized the sand/reef interface in the absence of gutters. Juveniles aggregated infrequently due to absence of habitat features that mediated aggregation. Acoustic tracks of adults revealed periods of inactivity up to 27 hr. Juveniles spent significant amounts of time inactive, punctuated with short bouts of swimming. Juveniles utilized moderate activity spaces (3,510–583,990 m²) centered over a core area of the Sea-Grass Bed but also ranged over much larger areas of the bay. Use of space by H. portusjacksoni is strongly influenced by habitat characteristics throughout its life history
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Habitat-Mediated Use of Space by Juvenile and Mating Adult Port Jackson Sharks, Heterodontus portusjacksoni, in Eastern Australia.
Honolulu University of Hawaii Press, 2009Co-Authors: Powter, David Mark, Gladstone WilliamAbstract:v. ill. 23 cm.QuarterlyStudies of spatial ecology of demersal sharks are critical to understanding the significance of habitat variation; however, limited information exists. Spatial ecology of adult Heterodontus portusjacksoni was studied at three locations on the central and southern coast of New South Wales, Australia, from January 2002 to December 2005. Juveniles within a nursery area were studied from December 2002 to December 2005. Tag-recapture, day and night underwater visual census, and acoustic tagging were used. Adults returned annually to the same coastal breeding reefs for up to four consecutive years. Individual juveniles resided within a Sea-Grass nursery area for at least 2 yr and were not uniformly distributed throughout the nursery. Adult females often sheltered in aggregations in gutters as a male avoidance strategy, and both sexes utilized the sand/reef interface in the absence of gutters. Juveniles aggregated infrequently due to absence of habitat features that mediated aggregation. Acoustic tracks of adults revealed periods of inactivity up to 27 hr. Juveniles spent significant amounts of time inactive, punctuated with short bouts of swimming. Juveniles utilized moderate activity spaces (3,510–583,990 m2) centered over a core area of the Sea-Grass Bed but also ranged over much larger areas of the bay. Use of space by H. portusjacksoni is strongly influenced by habitat characteristics throughout its life history
Li Zhi - One of the best experts on this subject based on the ideXlab platform.
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relations of water self purify ability with water dynamics biological and chemical factor in Sea Grass Bed ecosystem in tieshan bay
Marine Environmental Science, 2012Co-Authors: Li ZhiAbstract:Based on the data obtained in Tieshan Bay Sea-Grass Bed ecosystem during Jan to Nov.2008,the relations of the water self-purify ability with water dynamics,biological and chemical factors were studied.The results showed that there were three reasons for the high self-purify ability of water in Sea-Grass Bed ecosystem.The first,the water dynamics in this Sea area were strong tide and reciprocating which serves most to the high self-purify ability of water.The second,In the environment of the Sea area there are the proper temperature,affluent dissolved oxygen,high ability of oxygen recovery which helped to breeding and growth of aerobe.The obvious low TOC and affluent TN was reflection of rapid degradation of organics,rapid regeneration of nutrient and high chemical purification ability.The third is the impact of biological chain in this Sea area.The significant negative correlation between DO and biological factors helped to prove that.Affluent TN,obvious low DIN,prosperous zooplankton,prosperous phytoplankton and rich biodiversity were comprehensive embody of high biological purification ability in this Sea area.The comparison of chemical purification ability and biological purification showed the stronger advantages.
Powter, David Mark - One of the best experts on this subject based on the ideXlab platform.
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Habitat-mediated use of space by juvenile and mating adult Port Jackson sharks, Heterodontus portusjacksoni, in Eastern Australia
University of Hawaii Press, 2009Co-Authors: Powter, David Mark, Gladstone WilliamAbstract:Studies of spatial ecology of demersal sharks are critical to understanding the significance of habitat variation; however, limited information exists. Spatial ecology of adult Heterodontus portusjacksoni was studied at three locations on the central and southern coast of New South Wales, Australia, from January 2002 to December 2005. Juveniles within a nursery area were studied from December 2002 to December 2005. Tag-recapture, day and night underwater visual census, and acoustic tagging were used. Adults returned annually to the same coastal breeding reefs for up to four consecutive years. Individual juveniles resided within a Sea-Grass nursery area for at least 2 yr and were not uniformly distributed throughout the nursery. Adult females often sheltered in aggregations in gutters as a male avoidance strategy, and both sexes utilized the sand/reef interface in the absence of gutters. Juveniles aggregated infrequently due to absence of habitat features that mediated aggregation. Acoustic tracks of adults revealed periods of inactivity up to 27 hr. Juveniles spent significant amounts of time inactive, punctuated with short bouts of swimming. Juveniles utilized moderate activity spaces (3,510–583,990 m²) centered over a core area of the Sea-Grass Bed but also ranged over much larger areas of the bay. Use of space by H. portusjacksoni is strongly influenced by habitat characteristics throughout its life history
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Habitat-Mediated Use of Space by Juvenile and Mating Adult Port Jackson Sharks, Heterodontus portusjacksoni, in Eastern Australia.
Honolulu University of Hawaii Press, 2009Co-Authors: Powter, David Mark, Gladstone WilliamAbstract:v. ill. 23 cm.QuarterlyStudies of spatial ecology of demersal sharks are critical to understanding the significance of habitat variation; however, limited information exists. Spatial ecology of adult Heterodontus portusjacksoni was studied at three locations on the central and southern coast of New South Wales, Australia, from January 2002 to December 2005. Juveniles within a nursery area were studied from December 2002 to December 2005. Tag-recapture, day and night underwater visual census, and acoustic tagging were used. Adults returned annually to the same coastal breeding reefs for up to four consecutive years. Individual juveniles resided within a Sea-Grass nursery area for at least 2 yr and were not uniformly distributed throughout the nursery. Adult females often sheltered in aggregations in gutters as a male avoidance strategy, and both sexes utilized the sand/reef interface in the absence of gutters. Juveniles aggregated infrequently due to absence of habitat features that mediated aggregation. Acoustic tracks of adults revealed periods of inactivity up to 27 hr. Juveniles spent significant amounts of time inactive, punctuated with short bouts of swimming. Juveniles utilized moderate activity spaces (3,510–583,990 m2) centered over a core area of the Sea-Grass Bed but also ranged over much larger areas of the bay. Use of space by H. portusjacksoni is strongly influenced by habitat characteristics throughout its life history
Martin R. Speight - One of the best experts on this subject based on the ideXlab platform.
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Printed in the United Kingdom Diel variation in Sea Grass dwelling shrimp: when to sample at night?
2013Co-Authors: S. De Grave, D. Livingston, Martin R. SpeightAbstract:The present study investigates hourly variation in nocturnal abundance £uctuations in a tropical, Caribbean Sea Grass Bed. As expected, results indicate that signi¢cant diel variation is present. In addition all dominant species show an abundance peak shortly after sunset, with numbers gradually declining throughout the night. It is therefore suggested that nocturnal samples are not only incorporated into any sampling regime, but that nocturnal samples are taken within two hours after sunset. Tropical Sea Grass Beds and their associated epiphytes form a habitat for a diverse assemblage of organisms, ranging from micro£ora and fauna through to manatees (Nakaoka, 2005). Although numerous studies have descriBed the structural elements of the Sea Grass habitat, the basic functional relationships of the community as a whole remain only partly understood (Nakaoka, 2005). In part this is due to a plethora of temporal sampling regimes and di¡ering sampling techniques (e.g. beam trawl, drop net, sweep nets) being employed. This is particularly evident for the epifaunal assemblage, where caridean and dendrobranchiate shrimps dominate (e.g. Greening & Livingston, 1982; Barba et al., 2005; Garc|¤a Raso et al., 2006). In view of this numerical dominance, Sea Grass dwelling shrimps constitute an important trophic link between primary production and higher trophic levels. Since the 1980s the diel variation in activity patterns of Sea Grass dwelling shrimp has been documented several time
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Diel variation in Sea Grass dwelling shrimp: when to sample at night?
Journal of the Marine Biological Association of the United Kingdom, 2006Co-Authors: S. De Grave, D. Livingston, Martin R. SpeightAbstract:The present study investigates hourly variation in nocturnal abundance fluctuations in a tropical, Caribbean Sea Grass Bed. As expected, results indicate that significant diel variation is present. In addition all dominant species show an abundance peak shortly after sunset, with numbers gradually declining throughout the night. It is therefore suggested that nocturnal samples are not only incorporated into any sampling regime, but that nocturnal samples are taken within two hours after sunset.
Haelip Suh - One of the best experts on this subject based on the ideXlab platform.
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secondary production of jassa slatteryi amphipoda ischyroceridae on a zostera marina SeaGrass Bed in southern korea
Marine Ecology Progress Series, 2006Co-Authors: Seung Jin Jeong, Haelip SuhAbstract:On the basis of monthly samples, we measured the secondary production of the amphi- pod Jassa slatteryi Conlan 1990, on a Zostera marina L. SeaGrass Bed in Gwangyang Bay, southern Korea. The standing crop of SeaGrass showed 2 peaks in spring and fall, with maximum biomass in May. Biomass distribution of J. slatteryi was positively correlated with the standing crop of SeaGrass (p < 0.05), suggesting that there is a biological interaction between these 2 species. J. slatteryi dis- plays 2 main breeding periods during the year; in spring (March to May) and in fall (October to December). The biomass of J. slatteryi and the standing crop of SeaGrass in the spring was much higher than in the fall. The annual secondary production of J. slatteryi in the Gwangyang Bay Sea- Grass Bed (20.07 g dry weight m -2 yr -1 ) is the highest reported in amphipods inhabiting SeaGrass Beds. However, the annual production:biomass (P:B) ratio, at 5.21, was lower than recorded previously in both temperate and tropical SeaGrass Beds because the number of generations decreases the P:B ratio. The combination of high abundance and secondary production suggests an important role for J. slatteryi in the SeaGrass-Bed ecosystem as a trophic link from primary producers to higher con- sumers.