Recreational kelp harvest in Smith and Minor Islands aquatic reserve
Presentation Abstract
Recreational intertidal kelp harvest is prevalent during spring and summer low tides on beaches in the Smith and Minor Islands Aquatic Reserve (SMIAR), located on the west side of Whidbey Island. The aim of this study was to gather information about harvester practices and evaluate potential impacts of recreational harvest on an intertidal kelp community with a focus on Alaria marginata and Saccharina spp. Over three years, the SMIAR Citizen Stewardship Committee observed spatial and temporal harvester patterns, measured wet weight of harvester buckets, and conducted harvester interviews at Libbey Beach, a popular beach access site. Among the kelp harvesters surveyed, we found most were aware of Washington State seaweed harvest regulations and around 85% of harvest bucket weights were under the daily limit. A. marginata was the target species for the majority of harvesters followed by Saccharina spp. Peak harvest occurred in April and May, and tapered in June and July. Concurrently, the Washington State Department of Natural Resources led a harvest treatment study using a randomized block design to investigate the impact of sustainable harvest (cut 12” above the holdfast) and unsustainable harvest (cut below the meristem). Target species’ density, blade length, sporophyll length, and weight-length relationships were recorded monthly during low tide cycles from May to July. Our research indicates that exposure time strongly influenced intertidal kelp survivorship during the spring and summer. We also found notable differences in A. Marginata density, mean blade length, and sporophyll length between treatments (sustainble harvest, unsustainable harvest and control).
Session Title
Posters: Habitat Restoration & Protection
Conference Track
SSE18: Posters
Conference Name
Salish Sea Ecosystem Conference (2018 : Seattle, Wash.)
Document Type
Event
SSEC Identifier
SSE18-83
Start Date
5-4-2018 11:30 AM
End Date
5-4-2018 1:30 PM
Type of Presentation
Poster
Genre/Form
conference proceedings; presentations (communicative events); posters
Contributing Repository
Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.
Subjects – Topical (LCSH)
Kelps--Washington (State)--Whidbey Island; Kelps--Harvesting
Geographic Coverage
Salish Sea (B.C. and Wash.); Whidbey Island (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
Recreational kelp harvest in Smith and Minor Islands aquatic reserve
Recreational intertidal kelp harvest is prevalent during spring and summer low tides on beaches in the Smith and Minor Islands Aquatic Reserve (SMIAR), located on the west side of Whidbey Island. The aim of this study was to gather information about harvester practices and evaluate potential impacts of recreational harvest on an intertidal kelp community with a focus on Alaria marginata and Saccharina spp. Over three years, the SMIAR Citizen Stewardship Committee observed spatial and temporal harvester patterns, measured wet weight of harvester buckets, and conducted harvester interviews at Libbey Beach, a popular beach access site. Among the kelp harvesters surveyed, we found most were aware of Washington State seaweed harvest regulations and around 85% of harvest bucket weights were under the daily limit. A. marginata was the target species for the majority of harvesters followed by Saccharina spp. Peak harvest occurred in April and May, and tapered in June and July. Concurrently, the Washington State Department of Natural Resources led a harvest treatment study using a randomized block design to investigate the impact of sustainable harvest (cut 12” above the holdfast) and unsustainable harvest (cut below the meristem). Target species’ density, blade length, sporophyll length, and weight-length relationships were recorded monthly during low tide cycles from May to July. Our research indicates that exposure time strongly influenced intertidal kelp survivorship during the spring and summer. We also found notable differences in A. Marginata density, mean blade length, and sporophyll length between treatments (sustainble harvest, unsustainable harvest and control).
