Experimental studies on predation and cannibalism of the settlers of Chasmagnathus granulata and Cyrtograpsus angulatus (Brachyura: Grapsidae)


Contact
kanger [ at ] awi-bremerhaven.de

Abstract

The grapsid crabs Chasmagnathus granulata and Cyrtograpsus angulatus are considered as key species within the benthic communities of estuaries and brackish coastal lagoons in the southwestern Atlantic region. In controlled laboratory experiments, we studied the intensity of interspecific predation as well as intra- and intercohort cannibalism in setllers in relation to refuge availability, predator characteristics (species, size, sex, nutritional state), and the presence or absence of an alternative food source (Artemia nauplii). In both species, the intensity of intracohort cannibalism among recently settled crabs (instars I and II, "settlers") was low, with ca. 5% mortality during 48 h experimental observation periods. Larger juveniles and adults of both species, by contrast, preyed heavily on the settlers. Predation was significantly reduced when refuges were available for the settlers. Hunger of the predators enhanced in general the predation rate. In the presence of alternative food, the consumption of settlers was significantly reduced. In C. granulata, adult females ate more settlers than the males, probably as a consequence of differences in the morphometric traits of their chelae. Cannibalism and predation by juvenile and adult crabs may play an important role in the regulation of recruitment success for both species and hence, in the structure of estuarine benthic communities.



Item Type
Article
Authors
Divisions
Programs
Publication Status
Published
Eprint ID
4669
Cite as
Luppi, T. A. , Spivak, E. D. and Anger, K. (2001): Experimental studies on predation and cannibalism of the settlers of Chasmagnathus granulata and Cyrtograpsus angulatus (Brachyura: Grapsidae) , Journal of Experimental Marine Biology and Ecology, 265 , pp. 29-48 .


Download
[thumbnail of Fulltext]
Preview
PDF (Fulltext)
Lup2001a.pdf

Download (223kB) | Preview
Cite this document as:

Share
Add to AnyAdd to TwitterAdd to FacebookAdd to LinkedinAdd to PinterestAdd to Email

Research Platforms
N/A

Campaigns
N/A


Actions
Edit Item Edit Item