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| George, Sb. |
| Differences in egg and larval quality for some sea urchins and seastars were investigated in the field acid in the laboratory. In the field, sea urchins and seastars found at sites with an abundant supply of food were larger, and they produced large numbers of large, high quality eggs. For some female seastars, nutritional history determined the response to variation in food supply in the laboratory. While an increase in food ration did not affect the size of eggs produced by females from the favorable site, an increase in food ration led to an increase in egg size for those from the less favorable site. For all the echinoderms examined, egg numbers decreased when conditions became unfavorable. Larvae from females living in favorable environments grew and... |
| Tipo: Text |
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| Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/00094/20488/18158.pdf |
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| Young, Cm; Devin, Mg; Jaeckle, Wb; Ekaratne, Suk; George, Sb. |
| Planktotrophy is a relatively common developmental mode among bathyal and abyssal echinoderms, but the sources of food used by deep-sea planktotrophic larvae remain generally unknown. Very few deep-sea echinoderm larvae have been collected in plankton samples, so we do not know whether larvae migrate to the euphotic zone to feed or if they rely on bacteria or detritus at greater depths. We approached this question indirectly by investigating whether larvae of bathyal echinoids can tolerate the temperatures they would encounter in the euphotic zone and whether they possess sufficient energy stores to migrate to the euphotic zone without feeding. Twenty-four hour survival at 20 and 24 degrees C was always much lower than survival at colder temperatures, but... |
| Tipo: Text |
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| Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/00094/20485/18155.pdf |
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