A geometrical model for the effect of interference on food intake

Authors: Rappoldt, C., Stillman, R.A. and Ens, B.J.

Journal: Ecological Modelling

Volume: 221

Issue: 2

Pages: 147-151

ISSN: 0304-3800

DOI: 10.1016/j.ecolmodel.2009.10.007

Abstract:

Interference competition is often due to kleptoparasitism (food stealing). In which case, the attack distance, the distance over which one animal attacks another in an attempt to steal food, determines to a large extent the competitor density range over which interference significantly affects the intake rate of foraging animals. We develop a simple model of kleptoparasitism containing three parameters: attack distance, the density of foraging animals and a single dimensionless parameter α which summarizes the non-geometrical aspects of the interference process. Dominant and subdominant animals are not considered separately. The model predicts that the average intake rate will decrease exponentially with animal density and that a measure of the strength of interference depends on attack distance squared. The simple model is compared with a much more detailed individual-based foraging model from the literature. Simulated average intake rates are indeed well approximated by an exponential decrease with competitor density. Also the measure of interference behaves in the way expected from the simple model. By explaining the shape of the relationship between intake rate and animal density, the simple model provides insight into the behaviour of the detailed behavioural model. Insight into the role of geometry is important in the interpretation of field results and in the further development of detailed foraging models. © 2009 Elsevier B.V. All rights reserved.

Source: Scopus

A geometrical model for the effect of interference on food intake

Authors: Rappoldt, C., Stillman, R.A. and Ens, B.J.

Journal: ECOLOGICAL MODELLING

Volume: 221

Issue: 2

Pages: 147-151

eISSN: 1872-7026

ISSN: 0304-3800

DOI: 10.1016/j.ecolmodel.2009.10.007

Source: Web of Science (Lite)

A geometrical model for the effect of interference on food intake

Authors: Rappoldt, C., Stillman, R.A. and Ens, B.J.

Journal: Ecological Modelling

Volume: 221

Pages: 147-151

ISSN: 0304-3800

DOI: 10.1016/j.ecolmodel.2009.10.007

Abstract:

Interference competition is often due to kleptoparasitism (food stealing). In which case, the attack distance, the distance over which one animal attacks another in an attempt to steal food, determines to a large extent the competitor density range over which interference significantly affects the intake rate of foraging animals.

We develop a simple model of kleptoparasitism containing three parameters: attack distance, the density of foraging animals and a single dimensionless parameter α which summarizes the non-geometrical aspects of the interference process. Dominant and subdominant animals are not considered separately. The model predicts that the average intake rate will decrease exponentially with animal density and that a measure of the strength of interference depends on attack distance squared.

The simple model is compared with a much more detailed individual-based foraging model from the literature. Simulated average intake rates are indeed well approximated by an exponential decrease with competitor density. Also the measure of interference behaves in the way expected from the simple model. By explaining the shape of the relationship between intake rate and animal density, the simple model provides insight into the behaviour of the detailed behavioural model.

Insight into the role of geometry is important in the interpretation of field results and in the further development of detailed foraging models.

http://dx.doi.org/10.1016/j.ecolmodel.2009.10.007

Source: Manual

Preferred by: Richard Stillman