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Induced vertical migration in copepods as a defence against invertebrate predation
I 118
L BiologicalOceanography
OI.R (1990)37 (12)
analysis of bottle and net samples of phytoplankton, llydrobioL J. (a translation of Gidrobiol. Zh.), 25(4):82-85.
oceanogr. Soc. Japan, 45(5):301-309. KORDI, Ansan, P.O. Box 29, Seoul 425-600, Korea.
Results of the use of chambers of different volume to count large phytoplankton species in bottle and net samples are analyzed statistically. The abundance figure obtained by inspection of an 0.06-mL sample, constituting 6% of the bottle sample, in a Najotte chamber is an average of 50% greater than that obtained in a total count. Inspection of 1/25 of a net plankton sample gives an abundance figure that is 30% lower than that obtained in a total count. It is recommended that large phytoplankton be counted in bottle samples. Moscow Univ., USSR.
90:7133 Mikheyeva, T.M., 1989. Methods of counting nannophytoplankton (a survey) [with a critical analysis and an evaluation of their application potenfial]. llydrobioL J. (a translation of GidrobioL Zh.), 25(4):I-17. Belorussian Univ., Minsk, USSR.
90:7129 Brandini, F.P., 1990. I iydrography and characteristics of the phytoplankton in shelf and oceanic waters off southeastern Brazil during winter (July/August 1982) and summer (February/March 1984). tlydrobiologia, 196(2): 11 !-148. Ctr. de Biol. Marinha, Univ. Federal do Paran~i, Curitiba, Paran~t 80020, Brazil.
Here I report rapid initiation of vertical migration in previously non-migrating freshwater copepods inside large in-situ enclosures on exposure to an invertebrate predator. Responses of copepods to water that had previously held captive predators suggest that a chemical cue is involved. These results show that crustacean zooplankton may be capable of flexible, predator-sensitive foraging and suggest a mechanism for rapid changes in migration patterns. Dept. of Zool., 6270 Univ. Blvd., Univ. of British Columbia, Vancouver, BC V6T 2A9, Canada.
90:7130 Chang, C.-tl. and Rang Iluang, 1989. Biomass and productivity of size-fractlonated ph)toplankton in the coastal water of southwestern Taiwan. Acta oceanogr, laiwan~ 23:86-94. Inst. of Oceanogr., Natl. Taiwan Univ., Taipei, Taiwan. 90-7131 Chin-Leo, Gerardo and D.L. Kirchman, 1990. Unbalanced growth in natural assemblages of marine bacterioplankton. Mar. Ecol.-Prog. Ser., 63(i):!-8. In this study we examined whether unbalanced growth can be observed with marine bacterial assemblages. Using seawater cultures of bacteria, we compared rates of bacterial DNA and protein syntheses with growth rate by measuring incorporation rates of thymidine and leucine, and changes in bacterial abundance over time. As predicted by the unbalanced growth model, rates of protein synthesis changed faster than rates of DNA synthesis prior to shifts in growth rate. The unbalanced growth model may explain why rates of thymidine and leucine incorporation occasionally do not covary. Univ. of Texas at Austin, Mar. Sci. Inst., Port Aransas, TX 78373, USA. 90:7132 Han, M.-S., Ken Furuya and Takahisa Nemoto, 1989. Phytoplankton distribution in a frontal region of Tokyo Bay, Japan in November 1985. J.
90:7134 Neill, W.E., 1990. Induced vertical migration in copepods as a defence against invertebrate predation. Nature, Lond~ 345(6275):524-526.
90:7135 Plavgi~, Marta, Vjero~ka Vojvodi6 and Bolena (~osovi~, 1990. Characterization of surface-active substances during a semi-field experiment on a phytoplankton bloom. Ana/ytica chim. Acta, 232(I): 131-140. Surface-active substances (SAS) were determined during the evolution of a phytoplankton bloom in a model plankton ecosystem by electrochemical methods. Separation and characterization of the organic material were also done on XAD-8 resin columns. Large amounts of the SAS, predominantly of the humic type, were present from the beginning of the experiment and partly masked the effects of organic substances released by phytoplankton. Although the transformation of the organic matter was obvious, no general trend in the amount or type of surfaceactive matter was observed during the experiment. Rudjer Boskovic Inst., Ctr. for Mar. Res. Zagreb, Bijenicka c. 54, 41001 Zagreb, Yugoslavia. 90:7136 Priscu, J.C. et al., 1990. Estimation of neutral lipid levels in Antarctic sea ice microalgae by nile red fluorescence. A ntarct. Sci, 2(2): 149-155. Dept. of Biol. Sci., Montana State Univ., Bozeman, MT 59717, USA.
L BiologicalOceanography
OI.R (1990)37 (12)
analysis of bottle and net samples of phytoplankton, llydrobioL J. (a translation of Gidrobiol. Zh.), 25(4):82-85.
oceanogr. Soc. Japan, 45(5):301-309. KORDI, Ansan, P.O. Box 29, Seoul 425-600, Korea.
Results of the use of chambers of different volume to count large phytoplankton species in bottle and net samples are analyzed statistically. The abundance figure obtained by inspection of an 0.06-mL sample, constituting 6% of the bottle sample, in a Najotte chamber is an average of 50% greater than that obtained in a total count. Inspection of 1/25 of a net plankton sample gives an abundance figure that is 30% lower than that obtained in a total count. It is recommended that large phytoplankton be counted in bottle samples. Moscow Univ., USSR.
90:7133 Mikheyeva, T.M., 1989. Methods of counting nannophytoplankton (a survey) [with a critical analysis and an evaluation of their application potenfial]. llydrobioL J. (a translation of GidrobioL Zh.), 25(4):I-17. Belorussian Univ., Minsk, USSR.
90:7129 Brandini, F.P., 1990. I iydrography and characteristics of the phytoplankton in shelf and oceanic waters off southeastern Brazil during winter (July/August 1982) and summer (February/March 1984). tlydrobiologia, 196(2): 11 !-148. Ctr. de Biol. Marinha, Univ. Federal do Paran~i, Curitiba, Paran~t 80020, Brazil.
Here I report rapid initiation of vertical migration in previously non-migrating freshwater copepods inside large in-situ enclosures on exposure to an invertebrate predator. Responses of copepods to water that had previously held captive predators suggest that a chemical cue is involved. These results show that crustacean zooplankton may be capable of flexible, predator-sensitive foraging and suggest a mechanism for rapid changes in migration patterns. Dept. of Zool., 6270 Univ. Blvd., Univ. of British Columbia, Vancouver, BC V6T 2A9, Canada.
90:7130 Chang, C.-tl. and Rang Iluang, 1989. Biomass and productivity of size-fractlonated ph)toplankton in the coastal water of southwestern Taiwan. Acta oceanogr, laiwan~ 23:86-94. Inst. of Oceanogr., Natl. Taiwan Univ., Taipei, Taiwan. 90-7131 Chin-Leo, Gerardo and D.L. Kirchman, 1990. Unbalanced growth in natural assemblages of marine bacterioplankton. Mar. Ecol.-Prog. Ser., 63(i):!-8. In this study we examined whether unbalanced growth can be observed with marine bacterial assemblages. Using seawater cultures of bacteria, we compared rates of bacterial DNA and protein syntheses with growth rate by measuring incorporation rates of thymidine and leucine, and changes in bacterial abundance over time. As predicted by the unbalanced growth model, rates of protein synthesis changed faster than rates of DNA synthesis prior to shifts in growth rate. The unbalanced growth model may explain why rates of thymidine and leucine incorporation occasionally do not covary. Univ. of Texas at Austin, Mar. Sci. Inst., Port Aransas, TX 78373, USA. 90:7132 Han, M.-S., Ken Furuya and Takahisa Nemoto, 1989. Phytoplankton distribution in a frontal region of Tokyo Bay, Japan in November 1985. J.
90:7134 Neill, W.E., 1990. Induced vertical migration in copepods as a defence against invertebrate predation. Nature, Lond~ 345(6275):524-526.
90:7135 Plavgi~, Marta, Vjero~ka Vojvodi6 and Bolena (~osovi~, 1990. Characterization of surface-active substances during a semi-field experiment on a phytoplankton bloom. Ana/ytica chim. Acta, 232(I): 131-140. Surface-active substances (SAS) were determined during the evolution of a phytoplankton bloom in a model plankton ecosystem by electrochemical methods. Separation and characterization of the organic material were also done on XAD-8 resin columns. Large amounts of the SAS, predominantly of the humic type, were present from the beginning of the experiment and partly masked the effects of organic substances released by phytoplankton. Although the transformation of the organic matter was obvious, no general trend in the amount or type of surfaceactive matter was observed during the experiment. Rudjer Boskovic Inst., Ctr. for Mar. Res. Zagreb, Bijenicka c. 54, 41001 Zagreb, Yugoslavia. 90:7136 Priscu, J.C. et al., 1990. Estimation of neutral lipid levels in Antarctic sea ice microalgae by nile red fluorescence. A ntarct. Sci, 2(2): 149-155. Dept. of Biol. Sci., Montana State Univ., Bozeman, MT 59717, USA.