PL EN


Preferences help
enabled [disable] Abstract
Number of results
1997 | 26 | 1 | 127-149
Article title

The effect of sex ratio on the population pattern and abundance of the predominant Antarctic Coppoda in croker passage

Content
Title variants
Languages of publication
EN
Abstracts
EN
Population structure analysis of five of the most abundant Calanoida species showed their life strategy to be highly individual, even between animals belonging to the same trophic levels. In phytophages, such as C. acutus, sex determination began in autumn, earlier in females than in males. Males generally, rather low in abundance, were present for a relatively short time of the year. They occurred in the deepest part of the water column, where fertilisation should take place. A similar pattern of reproductive peaks was observed in C. propinquus, though males were not so scarce as in the former species and adults were present in the entire water column, so fertilisation was possible everywhere. The population of R. gigas showed the presence of two generations per year. Females pre-dominate among adults. In summer, fertilisation occurred in the epipelagic water layer, while in winter it descended to the bathypelagic water. In M. gerlachei sex determination seems to be an ongoing process. Fertilisation takes place in the deepest part of the water column, thus indicating the bulk presence of males, while females were distributed nearly evenly throughout the water column, except for the surface layers. E. antarctica - a predator - started to breed in winter. The predominant females were often ob-served with a few spermatophores; this suggests that females can survive longer than males.
Keywords
Year
Volume
26
Issue
1
Pages
127-149
Physical description
References
Document Type
article
Publication order reference
M. Zmijewska, Institute of Oceanography, University of Gdansk, Al. Marszalka Pilsudskiego 46, 81-378 Gdynia, Poland
YADDA identifier
bwmeta1.element.element-from-psjc-2987a7c6-ed4e-396c-ad23-2a2a7a3cec96
Identifiers
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.