A 4-year series of sediment trap samples from a depth of 3.2 km in the Sargasso Sea (32°05′N, 64°15′W) has revealed seasonal variations in the flux of euthecosomatous pteropods. Total pteropod flux is related to seasonal variations of the total particulate and organic carbon flux with a lag of 1-1.5 months. High flux of pteropods (>200 specimens m-2 day-1) occurs in late winter to mid-summer. Shells of individual pteropod species arrive in deep water in a seasonal succession similar to that in the living assemblage. Peak fluxes of Styliola subula, Clio pyramidata and Limacina bulimoides were recorded from February to May. Limacina inflata, Limacina lesueuri and Cuvierina columnella entered the trap in maximum numbers from April to mid-August. Creseis virgula conica and C. acicula were most abundant from June to late August. The latter two are non-migrating, epipelagic pteropods and comprise <10% of the assemblage. Diel migrators dominate the pteropod assemblage (92%). During the summer months they appear to migrate at greater depth, without reaching the surface water. Although many young are produced, only a small fraction, about 4% in the case of L. inflata and L. bulimoides, survives and reaches maturity. Adult shell size of L. inflata and L. bulimoides varies seasonally, reaching maximum size during spring, probably in response to increasing food availability.
|Number of pages||24|
|Journal||Deep-Sea Research, Part A: Oceanographic Research Papers|
|State||Published - Mar 1988|
Bibliographical noteFunding Information:
Acknowledgements--We gratefullya cknowledget he assistance received from I. Breitinger( GPI, Universityo f Tiibingen), J. Erez (Hebrew University, Jerusalem), A. Lupke, J. van der Meij (both GPI, University of Tiibingen) and E. H. Ross (WHOI). We thank J. D. Milliman and two anonymous reviewers for their comments on the manuscript. This studyw as supported by the Sonderforschungsbereich( SFB 53) "Palfkolo-gie" (D30) and HE 697/3 of the Deutsche Forschungsgemeinschaft,a nd by the U.S. National Science Foundationu nder Grants OCE78-19813, OCE80-24130, and OCE82-19588 to WGD. This is ContributionN o. 6552 from the Woods Hole Oceanographic Institutiona nd No. 1129 from the Bermuda BiologicalS tation.