Eelgrass (Zostera marina) bed sampling: standard operating procedure, v. 1.0, Southwest Alaska Network
Dean TA and Bodkin JL. 2016. Eelgrass (Zostera marina) bed sampling: standard operating procedure, v. 1.0, Southwest Alaska Network. Natural Resource Report. NPS/SWAN/NRR—2016/1174. National Park Service. Fort Collins, Colorado
Eelgrass (Zostera marina) is the dominant seagrass in protected waters of the Gulf of Alaska and is broadly distributed in sheltered embayments, especially in habitats dominated by soft sediments where they often form “beds” or relatively monotypic stands that can cover much of the shallow (0 to 5 m depth) subtidal zone (McRoy 1968, 1970). Eelgrass is an important “living habitat” that serves as a nutrient filter, provides shelter for fish and a variety of invertebrates, and provides physical substrate for invertebrates and algae (Phillips 1974, 1984; Thayer and Phillips 1977; Jewett et al. 1999; Dean et al. 2000; Bostrom et al. 2006). Eelgrass is a major primary producer in the marine nearshore (McConnaughey and McRoy 1979) and because it is located in shallow water, is susceptible to oil spills and other human disturbances (Short and Wiley-Eschevaria 1996, Dean et al. 1998, Duarte 2002, Larkum et al. 2006, Short et al. 2006). Eelgrass is especially susceptible to dredging, anchor scars, and events that reduce light penetration into the water column such as runoff (increased turbidity) or nutrient addition (Walker et al. 1989, Oleson 1996, Hauxwell et al. 2003, Neckles et al. 2005, Terrados et al. 2006). The purpose of monitoring is to assess changes in the extent of eelgrass over time; specifically, changes in the cover and relative abundance of eelgrass. The sampling is designed to examine smaller spatial- (within beds of approximately 10,000 m2) and temporal-scale (several year) changes within eelgrass beds. These results are to be complemented by aerial imagery that examines changes in the distribution of eelgrass over the entire shore of each park on a less frequent basis (approximately once every 10 to 12 years; Harper and Morris 2004). Sampling will be conducted in eelgrass habitats within the Katmai (KATM) and Kenai Fjords (KEFJ), and Prince William Sound (PWS).
- Type
- Published Report
- Authors
- Dean, Thomas; Bodkin, James
- Date of Issue
- 2016-03
- Publisher
- National Park Service
- Units
- KATM , KEFJ , NRSS , SWAN
- Keywords
- eelgrass, Gulf of Alaska, long term monitoring, marine ecosystems, near shore, nearshore, Zostera marina
- Subjects
- Ecological Framework: Biological Integrity | Focal Species or Communities | Marine Communities