Salinity preferences of the estuarine crab Chasmagnathus granulata after long term acclimation to different salinities.

5. CERVINO C; LUQUET C; HAUT G; RODRIGUEZ E.

ATLANTICA

FURG

Lugar: Rio Grande, RS Brasil ; Año: 1996 vol. 18 p. 69 - 75

0102-1656

Males of the estuarine crab Chasmagnathus granulata were acclimated during 45 days to salinities of 7,12, 20 and 34, and then submitted to a preference assay for these same salinities. Crabs acclimated to higher salinities (20 and 34) clearly preferred the highest salinity tested, whereas those acclimated to low salinities did not show any significant preference (p> 0.05). These results are apparently related to the ion-regulating capacity developed during acclimation to different salinities. Crabs acclimated to low salinities (which presumably developed strong hyper-regulatory mechanisms) would find no advantage in choosing a high, iso-ionic salinity, while the preference behavior of crabs acclimated to high salinities might be of adaptive value, especially in environments with important daily changes in salinity.