Skip to main content

IMIS

A new integrated search interface will become available in the next phase of marineinfo.org.
For the time being, please use IMIS to search available data

 

[ report an error in this record ]basket (0): add | show Print this page

Physiological responses of two ecologically important Kenyan mangrove crabs exposed to altered salinity regimes
Gillikin, D.P.; De Wachter, B.; Tack, J.F. (2004). Physiological responses of two ecologically important Kenyan mangrove crabs exposed to altered salinity regimes. J. Exp. Mar. Biol. Ecol. 301(1): 93-109. dx.doi.org/10.1016/j.jembe.2003.09.024
In: Journal of Experimental Marine Biology and Ecology. Elsevier: New York. ISSN 0022-0981; e-ISSN 1879-1697, more
Peer reviewed article  

Available in  Authors 

Keywords
    Mangroves
    Neosarmatium meinerti (De Man, 1887) [WoRMS]; Neosarmatium smithi (H. Milne Edwards, 1853) [WoRMS]; Sesarmidae Dana, 1851 [WoRMS]
    ISW, Kenya, Gazi Bay [Marine Regions]; ISW, Kenya, Mida Creek [Marine Regions]
    Marine/Coastal; Brackish water
Author keywords
    ecophysiology; energy budget; osmoregulation; salinity tolerance; Sesarmidae

Authors  Top 

Abstract
    The potential long-term effects of altered salinity regimes on the bioenergetics of two ecologically important Kenyan mangrove crabs, Neosarmatium meinerti de Man, 1887 and Neosarmatium smithi H. Milne Edwards, 1853 were investigated in light of recent findings suggesting that groundwater redirection may alter salinity regimes in Kenyan mangroves. Although changes in groundwater may cause only small increases in salinities, these changes would be chronic and may impact crab populations already living above their optimal salinity. To assess potential impacts, fundamental physiological processes and hemolymph components were measured on animals acclimated to 16‰, 32‰, 48‰ and 65‰ for 4 weeks in a field laboratory. For comparative purposes, crabs were also sampled in the field. N. smithi survived poorly in all salinities except the control (32‰). Although high mortality in N. smithi did not allow for reliable estimations of an energy budget, mortality and osmoregulatory capacity shows that this species can osmoregulate for a limited time in elevated salinities (±1 week), but cannot withstand long-term hypersaline conditions. In contrast, N. meinerti survived well and was able to osmoregulate for 1 month in all salinity treatments. Nevertheless, their energy budget, was significantly reduced (to below 0) in the 65‰ treatment. Overall, this study shows that these two congeneric species exhibit different long-term responses to variations in salinity. However, they are both negatively effected by hypersaline conditions, suggesting that long-term alteration of mangrove salinity regimes may be detrimental for these ecologically important mangrove crab populations.

All data in the Integrated Marine Information System (IMIS) is subject to the VLIZ privacy policy Top | Authors