Predation by red-jointed fiddler crabs on congeners: interaction between body size and positive allometry of the sexually selected claw

Denson K. McLain, Ann E. Pratt and Allison S. Berry

Behavioral Ecology, 2003, vol. 14, issue 5, 741-747

Abstract: The enlarged (major) claw of male fiddler crabs is used in contests over breeding burrows and is waved to attract females. We recently discovered that males of the red-jointed fiddler crab, Uca minax, also use the claw to kill smaller-sized fiddler crabs, U. pugnax and U. pugilator, with which they co-occur in Atlantic coast salt marshes. Large U. minax males use walking legs or the enlarged claw to capture prey feeding on moist sand flats. On sand flats, small U. minax males and females are much less common than large males, suggesting that large males move onto sand flats to seek prey. Males of prey species use the major claw against attacking predators and, consequently, are more likely than females to escape. In laboratory experiments, large U. minax males were more likely to attack and kill small-clawed males and females than large-clawed males, consistent with a preference for more vulnerable, less threatening prey. The size of the major claw is a positive allometric function of body size. The allometric function varies little among species. Also, the mechanical advantage and indices of closing speed and closing force of the major claw, when corrected for body size, are not consistently greater in U. minax relative to prey species. Thus, predation by U. minax males may reflect the opportunity afforded by larger body size and positive allometric growth, which result in a major claw that is more massive than the prey it is directed against. Copyright 2003.

Date: 2003
References: Add references at CitEc
Citations:

Downloads: (external link)
http://hdl.handle.net/10.1093/beheco/arg065 (application/pdf)
Access to full text is restricted to subscribers.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:oup:beheco:v:14:y:2003:i:5:p:741-747

Ordering information: This journal article can be ordered from
https://academic.oup.com/journals

Access Statistics for this article

Behavioral Ecology is currently edited by Louise Barrett

More articles in Behavioral Ecology from International Society for Behavioral Ecology Oxford University Press, Great Clarendon Street, Oxford OX2 6DP, UK.
Bibliographic data for series maintained by Oxford University Press ().