Gain curves in depletable food patches: A test of five models with European starlings
Olsson, Ola LU
; Brown, JS
and Smith, Henrik
LU
(2001)
In Evolutionary Ecology Research
3(3).
p.285-310
- Abstract
- A forager's gain curve, the cumulative number of prey harvested from a patch as a function of time spent in the patch, influences optimal patch departure rules and interpretations of patch use data. We describe models of five different search strategies that yield different gain curves. Hence they would influence a forager's decision for patch departure differently and, consequently, how researchers should interpret patch residence times and giving-up densities. However, the models are virtually impossible to separate based on data of the gain curves per se. Therefore, we develop a series of diagnostic tests that can be used to discriminate among models. These tests consider how the instantaneous harvest rate within patches depends on... (More)
- A forager's gain curve, the cumulative number of prey harvested from a patch as a function of time spent in the patch, influences optimal patch departure rules and interpretations of patch use data. We describe models of five different search strategies that yield different gain curves. Hence they would influence a forager's decision for patch departure differently and, consequently, how researchers should interpret patch residence times and giving-up densities. However, the models are virtually impossible to separate based on data of the gain curves per se. Therefore, we develop a series of diagnostic tests that can be used to discriminate among models. These tests consider how the instantaneous harvest rate within patches depends on initial (IPD) and current prey density (CPD) and search time. We applied these tests to data collected from European starlings (Sturnus vulgaris) foraging in experimental food patches of known initial prey density. The starlings' harvest rate increased with CPD, an indication of diminishing returns. However, a given CPD yielded a lower instantaneous intake rate the higher the IPD. Thus, the two models most commonly assumed in foraging studies, systematic and random search, can be unequivocally rejected. Instead, we found support for a new model, negative stirring, in which the starlings spoil their own future foraging returns by aggregating the remaining prey items as they search. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/145851
- author
- Olsson, Ola
LU
; Brown, JS
and Smith, Henrik
LU
- organization
- publishing date
- 2001
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Evolutionary Ecology Research
- volume
- 3
- issue
- 3
- pages
- 285 - 310
- publisher
- Evolutionary Ecology Ltd
- external identifiers
-
- scopus:0001443333
- ISSN
- 1522-0613
- language
- English
- LU publication?
- yes
- id
- 08267f05-4aa8-4905-b80b-3e2b3c7e6814 (old id 145851)
- alternative location
- http://evolutionary-ecology.com/issues/v03n03/eear1227.pdf
- date added to LUP
- 2016-04-01 16:32:33
- date last changed
- 2022-01-28 20:28:32
@article{08267f05-4aa8-4905-b80b-3e2b3c7e6814,
abstract = {{A forager's gain curve, the cumulative number of prey harvested from a patch as a function of time spent in the patch, influences optimal patch departure rules and interpretations of patch use data. We describe models of five different search strategies that yield different gain curves. Hence they would influence a forager's decision for patch departure differently and, consequently, how researchers should interpret patch residence times and giving-up densities. However, the models are virtually impossible to separate based on data of the gain curves per se. Therefore, we develop a series of diagnostic tests that can be used to discriminate among models. These tests consider how the instantaneous harvest rate within patches depends on initial (IPD) and current prey density (CPD) and search time. We applied these tests to data collected from European starlings (Sturnus vulgaris) foraging in experimental food patches of known initial prey density. The starlings' harvest rate increased with CPD, an indication of diminishing returns. However, a given CPD yielded a lower instantaneous intake rate the higher the IPD. Thus, the two models most commonly assumed in foraging studies, systematic and random search, can be unequivocally rejected. Instead, we found support for a new model, negative stirring, in which the starlings spoil their own future foraging returns by aggregating the remaining prey items as they search.}},
author = {{Olsson, Ola and Brown, JS and Smith, Henrik}},
issn = {{1522-0613}},
language = {{eng}},
number = {{3}},
pages = {{285--310}},
publisher = {{Evolutionary Ecology Ltd}},
series = {{Evolutionary Ecology Research}},
title = {{Gain curves in depletable food patches: A test of five models with European starlings}},
url = {{https://lup.lub.lu.se/search/files/4703656/625070.pdf}},
volume = {{3}},
year = {{2001}},
}