Information and exploitation: Patch assessment strategies in birds and mammals.

Persistent Link:
http://hdl.handle.net/10150/185036
Title:
Information and exploitation: Patch assessment strategies in birds and mammals.
Author:
Valone, Thomas John.
Issue Date:
1990
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Animals are decision-makers. While we cannot examine directly their decision-making process, we can observe the results of such decisions: their behavior. Behavioral ecologists, attempt to understand and predict the behavior of animals. To do so, clearly requires an understanding of the kinds of information individuals possess about their environment. Here, I explore how foragers exploit resource patches. When resource items are discrete and hidden, individuals must estimate the quality of encountered patches. Solitary foragers can use two sources of information. First, they can obtain information by sampling a patch. This is called patch-sample information. Second, foragers may use their prior experience and learn the distribution of resources in the environment. Individuals that combine these two sources of information are called Bayesian foragers. Foragers that cannot distinguish patch differences must rely on patch-sample information. Those that can, should employ Bayesian estimation because this generates better patch estimates. I examined the patch assessment ability of a wide variety of species. When patch variation is small, Arizona pocket mice (Perognathus amplus), and round-tail ground squirrels (Spermophilus tereticaudus) use patch-sample information; when patch variation is great, they both are Bayesian foragers. Gambel's quail (Callipepla gambelii) and mourning doves use patch sample information regardless of patch variation, while Merriam's kangaroo rat appears to always employ Bayesian foraging. If patches are spatially predictable and quality is temporally predictable, foragers can use this information to generate patch estimates prior to exploitation. Inca doves (Columbina inca) do just this. Black-chinned hummingbirds (Archilochus alexandri) are Bayesian foragers in predictable environments but rely much more on patch-sample information in unpredictable environments. Group foragers can use one additional source of patch information: they can observe the foraging success of other group members. I call this public information. In a series of Monte Carlo simulations, I show that Public information allows groups to estimate patch quality faster than solitary foragers and may prevent the underutilization of patches. Individuals in groups that cannot obtain public information can be faced with a dilemma because each group member will generate a different patch estimate. These individuals should abandon the patch when the first individual does so.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Biology
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Ecology and Evolutionary Biology; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Rosenzweig, Michael

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleInformation and exploitation: Patch assessment strategies in birds and mammals.en_US
dc.creatorValone, Thomas John.en_US
dc.contributor.authorValone, Thomas John.en_US
dc.date.issued1990en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractAnimals are decision-makers. While we cannot examine directly their decision-making process, we can observe the results of such decisions: their behavior. Behavioral ecologists, attempt to understand and predict the behavior of animals. To do so, clearly requires an understanding of the kinds of information individuals possess about their environment. Here, I explore how foragers exploit resource patches. When resource items are discrete and hidden, individuals must estimate the quality of encountered patches. Solitary foragers can use two sources of information. First, they can obtain information by sampling a patch. This is called patch-sample information. Second, foragers may use their prior experience and learn the distribution of resources in the environment. Individuals that combine these two sources of information are called Bayesian foragers. Foragers that cannot distinguish patch differences must rely on patch-sample information. Those that can, should employ Bayesian estimation because this generates better patch estimates. I examined the patch assessment ability of a wide variety of species. When patch variation is small, Arizona pocket mice (Perognathus amplus), and round-tail ground squirrels (Spermophilus tereticaudus) use patch-sample information; when patch variation is great, they both are Bayesian foragers. Gambel's quail (Callipepla gambelii) and mourning doves use patch sample information regardless of patch variation, while Merriam's kangaroo rat appears to always employ Bayesian foraging. If patches are spatially predictable and quality is temporally predictable, foragers can use this information to generate patch estimates prior to exploitation. Inca doves (Columbina inca) do just this. Black-chinned hummingbirds (Archilochus alexandri) are Bayesian foragers in predictable environments but rely much more on patch-sample information in unpredictable environments. Group foragers can use one additional source of patch information: they can observe the foraging success of other group members. I call this public information. In a series of Monte Carlo simulations, I show that Public information allows groups to estimate patch quality faster than solitary foragers and may prevent the underutilization of patches. Individuals in groups that cannot obtain public information can be faced with a dilemma because each group member will generate a different patch estimate. These individuals should abandon the patch when the first individual does so.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectBiologyen_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineEcology and Evolutionary Biologyen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorRosenzweig, Michaelen_US
dc.contributor.committeememberVenable, D. Lawrenceen_US
dc.contributor.committeememberClark, Colinen_US
dc.contributor.committeememberBronstein, Judithen_US
dc.contributor.committeememberRussel, Stephenen_US
dc.identifier.proquest9024655en_US
dc.identifier.oclc708251342en_US
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