|Common Redshank foraging model: the usefulness of an existing model for optimal foraging and bird distribution in tidal areas|
Brinkman, A.G. (2006). Common Redshank foraging model: the usefulness of an existing model for optimal foraging and bird distribution in tidal areas. Wageningen UR. IMARES: Texel. 49 pp.
Computer programs; Distribution; Foraging behaviour; Intertidal environment; Models; Marine
An existing software program consisting of two modules SlikOft and Sliktijk were studied in order to check whether the programme was worth to revive. The programme described the foraging behaviour of the Common Redshank on an intertidal area. Twenty different prey species or types may be distinguished, each with their own energetic content and handling time needed by the bird. First, the code was checked on consistency, and it had to be concluded that the programme contained a number of errors, inconsistencies, and some incomprehensible choices. Nevertheless, there was one feature in the programme that was different to most other optimal foraging descriptions, namely the random distribution of prey in the intertidal area. The effect of such a random distribution for the potential energetic uptake rate by a bird was computed and compared to the potential intake rate in case of an even distribution, the one being normally applied in optimal foraging descriptions. The differences appeared to be small and in fact not relevant to support a random prey distribution in stead of an even distribution. The programme is not worth to revive. If needed, other programmes may serve as basis for more sophisticated descriptions. Some ideas of the developer are worth to be considered, and to be developed further. It is suggested to study the usefulness of other foraging descriptions on possible food intake, in which birds do not know the best foraging areas, learn from each other while searching for food, and in which food is found in certain areas and not spread over a large area.