Streaming Media
Presentation Abstract
Information on kelp forest dynamics within the Salish Sea is needed to understand and address stressors. Around 2014, large declines in kelp canopies were observed in the northeast Pacific, which were generally attributed to elevated seawater temperatures and Sea Star Wasting Disease. This event provided a natural, large scale experiment, allowing us to observe diverse responses across the Salish Sea landscape, and compare to other regions. We analyzed annual floating kelp canopy surveys from 2011 to 2020 along a gradient from the exposed coast to the Strait of Georgia, using long-term data from Washington’s outer coast, the southern Strait of Juan de Fuca, and DNR’s Aquatic Reserves at Smith and Minor Island, Cypress Island and Cherry Point. All of these locations saw kelp decreases around 2013-2015; with maximum deviations of 25% to more than 75% below the long-term mean. In subsequent years, canopy area returned to the long-term mean or greater at all locations, a marked contrast to the pattern in northern California where catastrophic losses occurred and kelp canopies have not recovered. The timing of recovery varied along the gradient: locations adjacent to the open ocean (the outer coast and western strait) returned to the long-term mean in 2015, while locations farther within Salish Sea were delayed until as late as 2018. We compared these patterns in kelp abundance to climate indices and temperature data in order to better understand links to climate. While climate appears to be an important driver, we continue to be challenged to quantify climate conditions, especially within the Salish Sea, which is influenced by terrestrial as well as oceanic factors. Other factors also likely contributed to the observed patterns, including Sea Star Wasting disease, response to Elwha River dam removals, individual kelp species attributes, and local environmental conditions.
Session Title
Kelp Restoration & Climate Change
Conference Track
SSE9: Nearshore
Conference Name
Salish Sea Ecosystem Conference (2022 : Online)
Document Type
Event
SSEC Identifier
SSE-traditionals-411
Start Date
26-4-2022 9:45 AM
End Date
26-4-2022 11:15 AM
Rights
Copying of this document in whole or in part is allowable only for scholarly purposes. It is understood, however, that any copying or publication of this document for commercial purposes, or for financial gain, shall not be allowed without the author's written permission.
Type
Text
Language
English
Kelp forest responses to the 2014 Marine Heat Wave: clues about environmental patterns and gradients within the southern Salish Sea.
Information on kelp forest dynamics within the Salish Sea is needed to understand and address stressors. Around 2014, large declines in kelp canopies were observed in the northeast Pacific, which were generally attributed to elevated seawater temperatures and Sea Star Wasting Disease. This event provided a natural, large scale experiment, allowing us to observe diverse responses across the Salish Sea landscape, and compare to other regions. We analyzed annual floating kelp canopy surveys from 2011 to 2020 along a gradient from the exposed coast to the Strait of Georgia, using long-term data from Washington’s outer coast, the southern Strait of Juan de Fuca, and DNR’s Aquatic Reserves at Smith and Minor Island, Cypress Island and Cherry Point. All of these locations saw kelp decreases around 2013-2015; with maximum deviations of 25% to more than 75% below the long-term mean. In subsequent years, canopy area returned to the long-term mean or greater at all locations, a marked contrast to the pattern in northern California where catastrophic losses occurred and kelp canopies have not recovered. The timing of recovery varied along the gradient: locations adjacent to the open ocean (the outer coast and western strait) returned to the long-term mean in 2015, while locations farther within Salish Sea were delayed until as late as 2018. We compared these patterns in kelp abundance to climate indices and temperature data in order to better understand links to climate. While climate appears to be an important driver, we continue to be challenged to quantify climate conditions, especially within the Salish Sea, which is influenced by terrestrial as well as oceanic factors. Other factors also likely contributed to the observed patterns, including Sea Star Wasting disease, response to Elwha River dam removals, individual kelp species attributes, and local environmental conditions.
