Presentation Abstract
Widely regarded as critical marine habitat, seagrass provides ecologically and economically valuable services in coastal areas worldwide. Eelgrass (Zostera marina) is one of five seagrass species native to the Pacific Northwest and is threatened by outbreaks of the marine protist Labyrinthula zosterae, the causative agent of seagrass wasting disease. Infection from L. zosterae causes necrotic lesions, limiting growth and compromising the health of eelgrass beds. To determine levels of wasting disease in subtidal eelgrass beds across a broad latitudinal gradient, we measured and compared disease prevalence and severity in 5 subtidal eelgrass beds in Puget Sound, 5 in the San Juan Islands, 4 on Calvert Island, British Columbia, and 4 in south eastern Alaska. Disease prevalence, the proportion of diseased blades to health blades, was highest in Puget Sound, and steadily decreased in sites further north. Severity, the proportion of diseased tissue to healthy tissue on infected blades, also varied between sites and geographic regions. To determine potential environmental drivers of disease across broad spatial scales, we also measured site characteristics: density, canopy height, water temperature, and salinity. Understanding broad-scale patterns of disease and environmental drivers of wasting disease outbreaks can inform key decisions regarding eelgrass conservation within and beyond the Salish Sea.
Session Title
Seagrass Cross-border Connections: Status and Trends
Keywords
Eelgrass, Seagrass, Seagrass wasting disease
Conference Track
SSE4: Ecosystem Management, Policy, and Protection
Conference Name
Salish Sea Ecosystem Conference (2018 : Seattle, Wash.)
Document Type
Event
SSEC Identifier
SSE4-111
Start Date
5-4-2018 10:00 AM
End Date
5-4-2018 10:15 AM
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)
Eelgrass--Diseases and pests--Salish Sea (B.C. and Wash.); Marine protozoa--Salish Sea (B.C. and Wash.); Virulence (Microbiology)
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
Included in
Fresh Water Studies Commons, Marine Biology Commons, Natural Resources and Conservation Commons, Terrestrial and Aquatic Ecology Commons
Latitudinal variation in seagrass wasting disease from Puget Sound to Alaska
Widely regarded as critical marine habitat, seagrass provides ecologically and economically valuable services in coastal areas worldwide. Eelgrass (Zostera marina) is one of five seagrass species native to the Pacific Northwest and is threatened by outbreaks of the marine protist Labyrinthula zosterae, the causative agent of seagrass wasting disease. Infection from L. zosterae causes necrotic lesions, limiting growth and compromising the health of eelgrass beds. To determine levels of wasting disease in subtidal eelgrass beds across a broad latitudinal gradient, we measured and compared disease prevalence and severity in 5 subtidal eelgrass beds in Puget Sound, 5 in the San Juan Islands, 4 on Calvert Island, British Columbia, and 4 in south eastern Alaska. Disease prevalence, the proportion of diseased blades to health blades, was highest in Puget Sound, and steadily decreased in sites further north. Severity, the proportion of diseased tissue to healthy tissue on infected blades, also varied between sites and geographic regions. To determine potential environmental drivers of disease across broad spatial scales, we also measured site characteristics: density, canopy height, water temperature, and salinity. Understanding broad-scale patterns of disease and environmental drivers of wasting disease outbreaks can inform key decisions regarding eelgrass conservation within and beyond the Salish Sea.
