. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. Carapace Width (mm) Figure 3. Estimated numbers of eggs per egg mass plotted against crab size as shown by 2-mm increments of carapace width (bars indicate 95% confidence levels) for female Scsarma sp. (nr. reticulatum) taken in field samples during 1989. ried eggs were developing. Females bearing eggs (oviger- ous) after 30 August possessed very light colored, inactive ovaries that showed no increase in weight while eggs were being carried (Fig. 8). Inferential statistical analyses we
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. Carapace Width (mm) Figure 3. Estimated numbers of eggs per egg mass plotted against crab size as shown by 2-mm increments of carapace width (bars indicate 95% confidence levels) for female Scsarma sp. (nr. reticulatum) taken in field samples during 1989. ried eggs were developing. Females bearing eggs (oviger- ous) after 30 August possessed very light colored, inactive ovaries that showed no increase in weight while eggs were being carried (Fig. 8). Inferential statistical analyses were not performed on these data because of small and variable sample sizes. Decalcified opercula The only day (5 July 1989) in which softened genital opercula were found in a large percentage of the sample (37%) during the study was near full moon. While few ovigerous females ( of females sampled) were found on this date, laboratory data suggested that the cohort with softened genital opercula should have laid eggs within 24 h. Indeed, 31% of the females collected on the following date (6 July 1989) were ovigerous, confirming the labo- ratory prediction. Because data were plotted at weekly intervals, collections made on these two dates were com- bined and a value of 23% appears on Figure 1. Laboratory mesoeosms Crabs held in laboratory mesoeosms did not produce a premolt spring brood of eggs possibly because of inad- equate substrate or diet. This problem seemed to have been corrected with the substitution of substrate from the natural habitat and the installation of halogen lights. The molting period was also offset from that recorded from field samples by approximately one month. A first brood was produced a minimum of 21 days (X = 34 days) fol- lowing the early season molt. This was followed by a sec- ond brood at X = days later, and a third brood at X = 25 days later. A fourth brood was produced by three crabs collected in early April, at X = days later, and t
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
