nieuwe zoekopdracht
[ meld een fout in dit record ]mandje (0): toevoegen | toon Print deze pagina

Experimental evidence for cryptic interference among socially foraging shorebirds
Bijleveld, A.I.; Folmer, E.O.; Piersma, T. (2012). Experimental evidence for cryptic interference among socially foraging shorebirds. Behav. Ecol. 23(4): 806-814. dx.doi.org/10.1093/beheco/ars034
In: Behavioral Ecology. Oxford University Press: New York. ISSN 1045-2249, meer
Peer reviewed article  

Beschikbaar in  Auteurs 

Author keywords
    agonistic interactions; attack rate; flock size; functional response;ideal free distribution; intraspecific competition

Auteurs  Top 
  • Bijleveld, A.I., meer
  • Folmer, E.O., meer
  • Piersma, T., meer

Abstract
    Foraging rate and the distribution of foragers depend on prey distribution in conjunction with interindividual interactions. Generalized functional response models predict intake rates and spatial distributions of foragers on the basis of resource distribution and interference competition. The adequacy of these models depends on how well they capture the foragers' essential behavior. In this paper, we report on the results of a foraging experiment designed to examine the mechanisms of interference competition using red knots Calidris canutus that feed on buried bivalves. Red knots are rarely observed to interfere in the field, but this does not imply absence of interference. Our experimental setup minimized resource depletion, which allowed us to quantify interference competition as the decline in intake rate as a function of group size, with prey density and social status as additional treatments. We found that intake rate and searching efficiency decreased with group size and that dominant birds had higher intake rates than subordinates. Additionally, time spent searching for prey increased with group size. The decrease in intake rate was not due to conventional interference mechanisms (such as kleptoparasitism and time spent interacting with conspecifics) but to "cryptic interference," that is, avoidance of physical encounters with conspecifics. To accurately predict intake rates and foraging distributions, theory and models need to account for the possibility that animals anticipate and try to avoid, at some costs, physical encounters with conspecifics (i.e., conflicts that would make conventional interference behavior visible).

Alle informatie in IMIS valt onder het VLIZ Privacy beleid Top | Auteurs 
IMIS is ontwikkeld en wordt gehost door het VLIZ, voor meer informatie contacteer .