Presentation Abstract

Habitat suitability models are useful to forecast how environmental change may affect the abundance or distribution of species of interest. In the case of harvested bivalves, those models may be used to estimate the vulnerability of this valued ecosystem good to stressors. Using literature-derived natural history information, rule-based habitat suitability models were constructed in a GIS for several bivalve species (Clinocardium nuttallii, Mya arenaria, and Tresus capax) that are recreationally and commercially harvested in NE Pacific estuaries, including in the Salish Sea. Spatially-explicit habitat maps were produced for two Oregon estuaries using environmental data (salinity, depth, sediment grain size, and burrowing shrimp density) from multiple studies (1960-2012). Habitat suitability values ranged from 1-4 (lowest to highest) depending on the number of environmental variables that fell within a bivalve’s tolerance limits. The models were tested by comparing the observed distribution of bivalves reported in benthic community studies (1996-2012) to the range of each suitability class. Results primarily showed that habitats of highest predicted suitability contained the greatest proportion of bivalve observations and highest population densities. Our model was further supported by logistic regression analyses that showed correspondence between predicted habitat suitability values and logistic model probabilities. We demonstrate how these models can be used as tools to forecast changes in the availability of suitable habitat for these species using projected changes in salinity and depth associated with environmental change scenarios. The advantage of this approach is that disparate, independent sets of existing data are sufficient to parameterize the models, and to produce and validate maps of habitat suitability. We believe that these models are transferable across estuaries (such as in the Salish Sea) and bivalve species, and thus can be applied to data-poor systems with only modest investment.

Session Title

Integrated Coastal Climate Change Modeling for Salish Sea Planning: Part II

Keywords

Bivalves, Habitat suitability

Conference Track

SSE5: Climate Change: Impacts, Adaptation, and Research

Conference Name

Salish Sea Ecosystem Conference (Seattle, WA : 2018)

Document Type

Event

SSEC Identifier

SSE5-604

Start Date

6-4-2018 2:45 PM

End Date

6-4-2018 3:00 PM

Type of Presentation

Oral

Contributing Repository

Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.

Geographic Coverage

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

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Apr 6th, 2:45 PM Apr 6th, 3:00 PM

Understanding the implications of a changing environment on harvested bivalve populations using habitat suitability models

Habitat suitability models are useful to forecast how environmental change may affect the abundance or distribution of species of interest. In the case of harvested bivalves, those models may be used to estimate the vulnerability of this valued ecosystem good to stressors. Using literature-derived natural history information, rule-based habitat suitability models were constructed in a GIS for several bivalve species (Clinocardium nuttallii, Mya arenaria, and Tresus capax) that are recreationally and commercially harvested in NE Pacific estuaries, including in the Salish Sea. Spatially-explicit habitat maps were produced for two Oregon estuaries using environmental data (salinity, depth, sediment grain size, and burrowing shrimp density) from multiple studies (1960-2012). Habitat suitability values ranged from 1-4 (lowest to highest) depending on the number of environmental variables that fell within a bivalve’s tolerance limits. The models were tested by comparing the observed distribution of bivalves reported in benthic community studies (1996-2012) to the range of each suitability class. Results primarily showed that habitats of highest predicted suitability contained the greatest proportion of bivalve observations and highest population densities. Our model was further supported by logistic regression analyses that showed correspondence between predicted habitat suitability values and logistic model probabilities. We demonstrate how these models can be used as tools to forecast changes in the availability of suitable habitat for these species using projected changes in salinity and depth associated with environmental change scenarios. The advantage of this approach is that disparate, independent sets of existing data are sufficient to parameterize the models, and to produce and validate maps of habitat suitability. We believe that these models are transferable across estuaries (such as in the Salish Sea) and bivalve species, and thus can be applied to data-poor systems with only modest investment.