Spatial variation in mortality among Puget Sound Pacific herring
Presentation Abstract
Pacific herring play a key role in the Puget Sound food web. This ecological role may depend on the maintenance of distinct spawning areas. These spawning areas are affected by drivers at the local- and basin-scale, which likely influence demographic rates such as mortality. Examining spatial differences in mortality may identify drivers and elucidate potential causes of shifts in biomass and age structure. We have developed a simple life history model in which mortality can vary either spatially or temporally. The model has a hierarchical structure in order to: 1) Explicitly estimate the degree of similarity in mortality rates across groups of herring populations and 2) Use available age and biomass data to estimate changes in mortality over time. We estimate high adult mortality rates, which correspond to a pattern of truncated age structure in Puget Sound. Estimated mortality varies spatially, with different mortality in different basins within Puget Sound. While recruitment is often considered the most important driver of herring population dynamics, we hypothesize that the mortality of older adults may play an important role in the population dynamics of herring in Puget Sound.
Session Title
Ecological and cultural context of Pacific herring in the Salish Sea
Conference Track
Species and Food Webs
Conference Name
Salish Sea Ecosystem Conference (2016 : Vancouver, B.C.)
Document Type
Event
Start Date
2016 12:00 AM
End Date
2016 12:00 AM
Location
2016SSEC
Type of Presentation
Oral
Genre/Form
presentations (communicative events)
Contributing Repository
Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.
Subjects – Topical (LCSH)
Pacific herring populations--Spawning--Washington (State)--Puget Sound--Geographical distribution; Pacific herring populations--Mortality--Washington (State)--Puget Sound
Geographic Coverage
Puget Sound (Wash.); Salish Sea (B.C. and Wash.)
Rights
This resource is displayed for educational purposes only and may be subject to U.S. and international copyright laws. For more information about rights or obtaining copies of this resource, please contact University Archives, Heritage Resources, Western Libraries, Western Washington University, Bellingham, WA 98225-9103, USA (360-650-7534; heritage.resources@wwu.edu) and refer to the collection name and identifier. Any materials cited must be attributed to the Salish Sea Ecosystem Conference Records, University Archives, Heritage Resources, Western Libraries, Western Washington University.
Type
Text
Language
English
Format
application/pdf
Spatial variation in mortality among Puget Sound Pacific herring
2016SSEC
Pacific herring play a key role in the Puget Sound food web. This ecological role may depend on the maintenance of distinct spawning areas. These spawning areas are affected by drivers at the local- and basin-scale, which likely influence demographic rates such as mortality. Examining spatial differences in mortality may identify drivers and elucidate potential causes of shifts in biomass and age structure. We have developed a simple life history model in which mortality can vary either spatially or temporally. The model has a hierarchical structure in order to: 1) Explicitly estimate the degree of similarity in mortality rates across groups of herring populations and 2) Use available age and biomass data to estimate changes in mortality over time. We estimate high adult mortality rates, which correspond to a pattern of truncated age structure in Puget Sound. Estimated mortality varies spatially, with different mortality in different basins within Puget Sound. While recruitment is often considered the most important driver of herring population dynamics, we hypothesize that the mortality of older adults may play an important role in the population dynamics of herring in Puget Sound.
