Skip Navigation

This Article
Right arrow FREE Full Text (PDF) Freely available
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Search for citing articles in:
ISI Web of Science (16)
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Visser, M. E.
Right arrow Search for Related Content
PubMed
Right arrow Articles by Visser, M. E.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© 1996 International Society for Behavioral Ecology

research-article

The influence of competition between foragers on clutch size decisions in an insect parasitoid with scramble larval competition

Marcel E. Visser

Department of Biology, Imperial College at Silwood Park, Ascot, Berkshire SL5 7PY, UK

ABSTRACT

The effect of competition between ovipositing females on their clutch size decisions is studied in animals that lay their eggs in discrete units of larval food (hosts). In such species the effect of competition depends on the form of the larval competition within such units. In insect parasitoids, there might either be contest (solitary parasitoids) or scramble competition (gregarious parasitoids) between larvae within a host For gregarious parasitoids, a decreasing clutch size with increasing competition between foragers is predicted. This prediction is tested in experiments using the parasitoid Aphaertta minuta. Parasitoids were either kept alone or in groups of four before the experiment, in which they were introduced singly in a patch containing unparasitized hosts. Animals kept together laid on average clutches of 0.74 eggs smaller than females kept alone (average clutch is 5.3), thereby confirming the prediction. Clutch size decreased with encounter number, which might be due to the adjustment of the female's estimate of the encounter rate with hosts. Finally, the results are compared with those reported for solitary parasitoids (that have scramble larval competition), for which it is predicted that the clutch size will increase with increasing levels of competition between females.

Key words: competition, clutch size, parasitoids, superparasitism.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 Proc R Soc BHome page
M. Goubault, A. F.S Mack, and I. C.W Hardy
Encountering competitors reduces clutch size and increases offspring size in a parasitoid with female-female fighting
Proc R Soc B, October 22, 2007; 274(1625): 2571 - 2577.
[Abstract] [Full Text] [PDF]

Home page
 Behav EcolHome page
J. C. Creighton
Population density, body size, and phenotypic plasticity of brood size in a burying beetle
Behav. Ecol., November 1, 2005; 16(6): 1031 - 1036.
[Abstract] [Full Text] [PDF]


Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.