Data from: Size-selectivity of predation by brown bears depends on the density of their sockeye salmon prey
Can variation in prey density drive changes in the intensity or direction of selective predation in natural systems? Despite ample evidence of density-dependent selection, the influence of prey density on predatory selection patterns has seldom been investigated empirically. We used 20 years of fiel...
Main Authors: | , , |
---|---|
Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
2013
|
Subjects: | |
Online Access: | http://hdl.handle.net/10255/dryad.45901 https://doi.org/10.5061/dryad.77f5q |
id |
ftdryad:oai:v1.datadryad.org:10255/dryad.45901 |
---|---|
record_format |
openpolar |
spelling |
ftdryad:oai:v1.datadryad.org:10255/dryad.45901 2023-05-15T18:42:09+02:00 Data from: Size-selectivity of predation by brown bears depends on the density of their sockeye salmon prey Cunningham, Curry James Ruggerone, Gregory T. Quinn, Thomas P. Hansen Creek Wood River System Bristol Bay Alaska Lake Aleknagik 2013-01-24T15:21:57Z http://hdl.handle.net/10255/dryad.45901 https://doi.org/10.5061/dryad.77f5q unknown doi:10.5061/dryad.77f5q/1 doi:10.1086/670026 PMID:23594549 doi:10.5061/dryad.77f5q Cunningham CJ, Ruggerone GT, Quinn TP (2013) Size-selectivity of predation by brown bears depends on the density of their sockeye salmon prey. The American Naturalist 181(5): 663-673. http://hdl.handle.net/10255/dryad.45901 Density dependence Foraging: behavior Selection: natural Fish Article 2013 ftdryad https://doi.org/10.5061/dryad.77f5q https://doi.org/10.5061/dryad.77f5q/1 https://doi.org/10.1086/670026 2020-01-01T14:59:36Z Can variation in prey density drive changes in the intensity or direction of selective predation in natural systems? Despite ample evidence of density-dependent selection, the influence of prey density on predatory selection patterns has seldom been investigated empirically. We used 20 years of field data on brown bears (Ursus arctos) foraging on sockeye salmon (Oncorhynchus nerka) in Alaska, to test the hypothesis that salmon density affects the strength of size-selective predation. Measurements from 41,240 individual salmon were used to calculate variance-standardized selection differentials describing the direction and magnitude of selection. Across the time series, the intensity of predatory selection was inversely correlated with salmon density; greater selection for smaller salmon occurred at low salmon densities as bears’ tendency to kill larger-than-average salmon was magnified. This novel connection between density dependence and selective predation runs contrary to some aspects of optimal foraging theory and differs from many observations of density-dependent selection because (1) the direction of selection remains constant while its magnitude changes as a function of density and (2) stronger selection is observed at low abundance. These findings indicate that sockeye salmon may be subject to fishery-induced size selection from both direct mechanisms and latent effects of altered predatory selection patterns on the spawning grounds, resulting from reduced salmon abundance. Article in Journal/Newspaper Ursus arctos Alaska Dryad Digital Repository (Duke University) Hansen Creek ENVELOPE(-96.803,-96.803,55.591,55.591) Sockeye ENVELOPE(-130.143,-130.143,54.160,54.160) Wood River ENVELOPE(-63.157,-63.157,82.502,82.502) |
institution |
Open Polar |
collection |
Dryad Digital Repository (Duke University) |
op_collection_id |
ftdryad |
language |
unknown |
topic |
Density dependence Foraging: behavior Selection: natural Fish |
spellingShingle |
Density dependence Foraging: behavior Selection: natural Fish Cunningham, Curry James Ruggerone, Gregory T. Quinn, Thomas P. Data from: Size-selectivity of predation by brown bears depends on the density of their sockeye salmon prey |
topic_facet |
Density dependence Foraging: behavior Selection: natural Fish |
description |
Can variation in prey density drive changes in the intensity or direction of selective predation in natural systems? Despite ample evidence of density-dependent selection, the influence of prey density on predatory selection patterns has seldom been investigated empirically. We used 20 years of field data on brown bears (Ursus arctos) foraging on sockeye salmon (Oncorhynchus nerka) in Alaska, to test the hypothesis that salmon density affects the strength of size-selective predation. Measurements from 41,240 individual salmon were used to calculate variance-standardized selection differentials describing the direction and magnitude of selection. Across the time series, the intensity of predatory selection was inversely correlated with salmon density; greater selection for smaller salmon occurred at low salmon densities as bears’ tendency to kill larger-than-average salmon was magnified. This novel connection between density dependence and selective predation runs contrary to some aspects of optimal foraging theory and differs from many observations of density-dependent selection because (1) the direction of selection remains constant while its magnitude changes as a function of density and (2) stronger selection is observed at low abundance. These findings indicate that sockeye salmon may be subject to fishery-induced size selection from both direct mechanisms and latent effects of altered predatory selection patterns on the spawning grounds, resulting from reduced salmon abundance. |
format |
Article in Journal/Newspaper |
author |
Cunningham, Curry James Ruggerone, Gregory T. Quinn, Thomas P. |
author_facet |
Cunningham, Curry James Ruggerone, Gregory T. Quinn, Thomas P. |
author_sort |
Cunningham, Curry James |
title |
Data from: Size-selectivity of predation by brown bears depends on the density of their sockeye salmon prey |
title_short |
Data from: Size-selectivity of predation by brown bears depends on the density of their sockeye salmon prey |
title_full |
Data from: Size-selectivity of predation by brown bears depends on the density of their sockeye salmon prey |
title_fullStr |
Data from: Size-selectivity of predation by brown bears depends on the density of their sockeye salmon prey |
title_full_unstemmed |
Data from: Size-selectivity of predation by brown bears depends on the density of their sockeye salmon prey |
title_sort |
data from: size-selectivity of predation by brown bears depends on the density of their sockeye salmon prey |
publishDate |
2013 |
url |
http://hdl.handle.net/10255/dryad.45901 https://doi.org/10.5061/dryad.77f5q |
op_coverage |
Hansen Creek Wood River System Bristol Bay Alaska Lake Aleknagik |
long_lat |
ENVELOPE(-96.803,-96.803,55.591,55.591) ENVELOPE(-130.143,-130.143,54.160,54.160) ENVELOPE(-63.157,-63.157,82.502,82.502) |
geographic |
Hansen Creek Sockeye Wood River |
geographic_facet |
Hansen Creek Sockeye Wood River |
genre |
Ursus arctos Alaska |
genre_facet |
Ursus arctos Alaska |
op_relation |
doi:10.5061/dryad.77f5q/1 doi:10.1086/670026 PMID:23594549 doi:10.5061/dryad.77f5q Cunningham CJ, Ruggerone GT, Quinn TP (2013) Size-selectivity of predation by brown bears depends on the density of their sockeye salmon prey. The American Naturalist 181(5): 663-673. http://hdl.handle.net/10255/dryad.45901 |
op_doi |
https://doi.org/10.5061/dryad.77f5q https://doi.org/10.5061/dryad.77f5q/1 https://doi.org/10.1086/670026 |
_version_ |
1766231772825124864 |