Evol Ecol Res 10: 823-834 (2008)     Full PDF if your library subscribes.

Optimal foraging and information gathering: how should animals invest in repeated foraging bouts within the same patch?

Yoshihisa Mori1 and Kensuke Nakata2

1Department of Animal Sciences, Teikyo University of Science and Technology, Yamanashi and 2Faculty of Contemporary Law, Tokyo Keizai University, Tokyo, Japan

Correspondence: Y. Mori, Department of Animal Sciences, Teikyo University of Science and Technology, Yatsusawa 2525, Uenohara, Yamanashi 409-0193, Japan.
e-mail: moripe@ntu.ac.jp


Questions: How much should animals invest in information gathering when they have no prior information about the present state of the foraging patch, and does the ability to use information have an effect on the size of the investment?

Mathematical method: Optimization of the size of investment when animals use the same foraging patch repeatedly.

Key assumptions: Animals determine the size of their foraging investment before each foraging bout. They make a first investment without having any prior information. They then use information gained from the experience of the first bout to estimate patch profitability. (The larger the investment during the first bout, the more accurate the estimate.)

Predictions: When patch profitability can be correctly estimated irrespective of the size of investment, animals should invest as if they were at a patch of average profitability. If larger investments do produce more accurate estimates, animals should make a greater investment than that for average profitability in the environment. The more likely it is that information proves to be invalid, the smaller the optimal investment in gaining that information. Therefore, it is expected that the species that relocates its foraging patch frequently makes a relatively smaller investment in its first foraging bout, whereas the species that exhibits strong patch tenacity makes a relatively greater investment in its first bout. Animals should pay the cost of the non-maximized gain for information that will help them to estimate foraging patch profitability more accurately and to enhance their future foraging.

Keywords: environmental uncertainty, information gathering, optimal foraging, patch use, repeated foraging.

IF you are connected using the IP of a subscribing institution (library, laboratory, etc.)
or through its VPN.


        © 2008 Yoshihisa Mori. All EER articles are copyrighted by their authors. All authors endorse, permit and license Evolutionary Ecology Ltd. to grant its subscribing institutions/libraries the copying privileges specified below without additional consideration or payment to them or to Evolutionary Ecology, Ltd. These endorsements, in writing, are on file in the office of Evolutionary Ecology, Ltd. Consult authors for permission to use any portion of their work in derivative works, compilations or to distribute their work in any commercial manner.

       Subscribing institutions/libraries may grant individuals the privilege of making a single copy of an EER article for non-commercial educational or non-commercial research purposes. Subscribing institutions/libraries may also use articles for non-commercial educational purposes by making any number of copies for course packs or course reserve collections. Subscribing institutions/libraries may also loan single copies of articles to non-commercial libraries for educational purposes.

       All copies of abstracts and articles must preserve their copyright notice without modification.