Linking predators to seasonality of upwelling: Using food web indicators and path analysis to infer trophic connections
Upwelling in eastern boundary current systems is a primary driver of ecosystem productivity. Typically, peak upwelling occurs during spring and summer, but winter upwelling may also be important to ecosystem functions. In this study, we investigated the hypothesis that winter and spring/summer upwel...
Main Authors: | , , , , , , , |
---|---|
Other Authors: | |
Format: | Article in Journal/Newspaper |
Language: | English unknown |
Published: |
Elsevier
|
Subjects: | |
Online Access: | https://ir.library.oregonstate.edu/concern/articles/3t945r379 |
id |
ftoregonstate:ir.library.oregonstate.edu:3t945r379 |
---|---|
record_format |
openpolar |
spelling |
ftoregonstate:ir.library.oregonstate.edu:3t945r379 2024-09-15T18:02:43+00:00 Linking predators to seasonality of upwelling: Using food web indicators and path analysis to infer trophic connections Thompson, Sarah Ann Sydeman, William J. Santora, Jarrod A. Black, Bryan A. Suryan, Robert M. Calambokidis, John Peterson, William T. Bograd, Steven J. Hatfield Marine Science Center https://ir.library.oregonstate.edu/concern/articles/3t945r379 English [eng] eng unknown Elsevier https://ir.library.oregonstate.edu/concern/articles/3t945r379 Copyright Not Evaluated Article ftoregonstate 2024-07-22T18:06:05Z Upwelling in eastern boundary current systems is a primary driver of ecosystem productivity. Typically, peak upwelling occurs during spring and summer, but winter upwelling may also be important to ecosystem functions. In this study, we investigated the hypothesis that winter and spring/summer upwelling, operating through indirect trophic interactions, are important to a suite of top predators in the California Current. To test this hypothesis, we collated information on upwelling, chlorophyll-a concentrations, zooplankton and forage fish, and related these to predator responses including rockfish growth, salmon abundance, seabird productivity and phenology (timing of egg-laying), and whale abundance. Seabird diets served in part as food web indicators. We modeled pathways of response using path analysis and tested for significance of the dominant paths with multiple regression. We found support for the hypothesis that relationships between upwelling and top predator variables were mediated primarily by intermediate trophic levels. Both winter and summer upwelling were important in path models, as were intermediate lower and mid trophic level functional groups represented by chlorophyll-a, zooplankton, and forage fish. Significant pathways of response explained from 50% to 80% of the variation of seabird (Cassin’s auklet (Ptychoramphus aleuticus) and common murre (Uria aalge)), humpback whale (Megaptera novaeangliae) and Chinook salmon (Oncorhynchus tshawytscha) dependent variables, whereas splitnose rockfish (Sebastes diploproa) showed no significant response pathways. Upwelling and trophic responses for salmon were established for both the year of ocean entry and the year of return, with zooplankton important in the year of ocean entry and forage fish important in the year of return. This study provides one of the first comparative investigations between upwelling and predators, from fish to marine mammals and birds within a geographically restricted area, demonstrates often difficult to establish "bottom-up" ... Article in Journal/Newspaper Common Murre Humpback Whale Megaptera novaeangliae Uria aalge uria ScholarsArchive@OSU (Oregon State University) |
institution |
Open Polar |
collection |
ScholarsArchive@OSU (Oregon State University) |
op_collection_id |
ftoregonstate |
language |
English unknown |
description |
Upwelling in eastern boundary current systems is a primary driver of ecosystem productivity. Typically, peak upwelling occurs during spring and summer, but winter upwelling may also be important to ecosystem functions. In this study, we investigated the hypothesis that winter and spring/summer upwelling, operating through indirect trophic interactions, are important to a suite of top predators in the California Current. To test this hypothesis, we collated information on upwelling, chlorophyll-a concentrations, zooplankton and forage fish, and related these to predator responses including rockfish growth, salmon abundance, seabird productivity and phenology (timing of egg-laying), and whale abundance. Seabird diets served in part as food web indicators. We modeled pathways of response using path analysis and tested for significance of the dominant paths with multiple regression. We found support for the hypothesis that relationships between upwelling and top predator variables were mediated primarily by intermediate trophic levels. Both winter and summer upwelling were important in path models, as were intermediate lower and mid trophic level functional groups represented by chlorophyll-a, zooplankton, and forage fish. Significant pathways of response explained from 50% to 80% of the variation of seabird (Cassin’s auklet (Ptychoramphus aleuticus) and common murre (Uria aalge)), humpback whale (Megaptera novaeangliae) and Chinook salmon (Oncorhynchus tshawytscha) dependent variables, whereas splitnose rockfish (Sebastes diploproa) showed no significant response pathways. Upwelling and trophic responses for salmon were established for both the year of ocean entry and the year of return, with zooplankton important in the year of ocean entry and forage fish important in the year of return. This study provides one of the first comparative investigations between upwelling and predators, from fish to marine mammals and birds within a geographically restricted area, demonstrates often difficult to establish "bottom-up" ... |
author2 |
Hatfield Marine Science Center |
format |
Article in Journal/Newspaper |
author |
Thompson, Sarah Ann Sydeman, William J. Santora, Jarrod A. Black, Bryan A. Suryan, Robert M. Calambokidis, John Peterson, William T. Bograd, Steven J. |
spellingShingle |
Thompson, Sarah Ann Sydeman, William J. Santora, Jarrod A. Black, Bryan A. Suryan, Robert M. Calambokidis, John Peterson, William T. Bograd, Steven J. Linking predators to seasonality of upwelling: Using food web indicators and path analysis to infer trophic connections |
author_facet |
Thompson, Sarah Ann Sydeman, William J. Santora, Jarrod A. Black, Bryan A. Suryan, Robert M. Calambokidis, John Peterson, William T. Bograd, Steven J. |
author_sort |
Thompson, Sarah Ann |
title |
Linking predators to seasonality of upwelling: Using food web indicators and path analysis to infer trophic connections |
title_short |
Linking predators to seasonality of upwelling: Using food web indicators and path analysis to infer trophic connections |
title_full |
Linking predators to seasonality of upwelling: Using food web indicators and path analysis to infer trophic connections |
title_fullStr |
Linking predators to seasonality of upwelling: Using food web indicators and path analysis to infer trophic connections |
title_full_unstemmed |
Linking predators to seasonality of upwelling: Using food web indicators and path analysis to infer trophic connections |
title_sort |
linking predators to seasonality of upwelling: using food web indicators and path analysis to infer trophic connections |
publisher |
Elsevier |
url |
https://ir.library.oregonstate.edu/concern/articles/3t945r379 |
genre |
Common Murre Humpback Whale Megaptera novaeangliae Uria aalge uria |
genre_facet |
Common Murre Humpback Whale Megaptera novaeangliae Uria aalge uria |
op_relation |
https://ir.library.oregonstate.edu/concern/articles/3t945r379 |
op_rights |
Copyright Not Evaluated |
_version_ |
1810440141947273216 |