. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 170 MARTINEZ ET AL. with the time of exposure (Fig. 1). They decreased sharply to less than 25% within 15-24 h at the highest (1300 mosm/kg) and lowest (740. 800 mosin/kg) salinities. Sur- vival was higher in seawater (1002 mosm/kg) and in salin- ities ranging from 900 to 1200 mosm/kg. Hydromineral regulation Acclimation time. The time of adaptation after a sudden change in salinity was evaluated at two low salinities (Fig. 2). In both media, the hemolymph osmolality decreased sharply within 12 h. After 15 h in the 740
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 170 MARTINEZ ET AL. with the time of exposure (Fig. 1). They decreased sharply to less than 25% within 15-24 h at the highest (1300 mosm/kg) and lowest (740. 800 mosin/kg) salinities. Sur- vival was higher in seawater (1002 mosm/kg) and in salin- ities ranging from 900 to 1200 mosm/kg. Hydromineral regulation Acclimation time. The time of adaptation after a sudden change in salinity was evaluated at two low salinities (Fig. 2). In both media, the hemolymph osmolality decreased sharply within 12 h. After 15 h in the 740-mosm/kg me- dium, hemolymph osmolality had decreased to 805 mosm/ kg—that is, to about 65 mosm/kg above the medium osmo- lality. As all crabs had died before 24 h, it was not possible to determine whether hemolymph osmolality had entirely stabilized at 15 h. After a transfer to the 800-mosm/kg medium, the hemolymph osmolality stabilized within 24 h. Its mean values were respectively 817 and 808 mosm/kg (no significant difference) after 24 h and 48 h in this medium. In subsequent experiments, the time of exposure to different media was based on these results and was kept in general at 15-24 h. Osmotic regulation. Upon the arrival of the crabs on board the ship following their transfer from the bottom, their hemolymph osmolality was 1025 ± 4 mosm/kg (n = 18) and 984 ± 12 mosm/kg (/i = 29) at the 13°N EPR and 9°N EPR sites respectively. The ability of the crabs to osmo- regulate was then evaluated in the range of tolerable salin- ities between 900 mosm/kg and 1200 mosm/kg. The crabs osmoconformed in the whole range of tested salinities (Fig. 3A). The hemolymph osmotic concentration was close to that of the medium, different from it by only 9 to 22 mosm/kg, 15 mosm/kg on average. The hemolymph osmolality was also measured in crabs maintained in the 800-mosm/kg medium, under a pressure of 260 bars. The mean value of hemolymph osmolality following this treatment for 13 h was 8
Size: 1732px × 1443px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
