Event Title

Long term monitoring of eelgrass, water and weather patterns in Padilla Bay, WA.

Presentation Abstract

The importance of eelgrass in nearshore ecosystem function and as an indicator of ecosystem health led to the establishment of a long-term monitoring program focused on tracking annual growth and distribution of eelgrass species (Z. marina and Z. japonica) in Padilla Bay, WA. This annual monitoring program was established in 2011 and consists of 126 permanent plots along three 4 km transects.

Eelgrass exhibits a complex response to environmental conditions driven primarily by temperature, light, and nutrients. Optimum growth requirements differ between Z. marina and Z. japonica, with the latter responding positively to warmer water temperatures and possessing an increased tolerance to high temperature extremes (Kaldy et al. 2015). Using long-term monitoring data from Padilla Bay, we investigated factors (i.e. temperature, light availability, water depth) that may help to explain patterns in eelgrass growth and performance. During the study period, we measured a two degree (°C) increase in mean water temperature, an increase in mean surface light (PAR millimoles/m2) and a decrease in mean water depth. Eelgrass measurements over the same time period reveal that the density and biomass of Z. japonica has dramatically increased, while Z. marina density and biomass have fluctuated over time with the lowest observed values in 2015.

These data suggest that the predicted increase in local temperature and sea level as a result of climate change may favor expansion of Z. japonica density and distribution, particularly in the upper and mid intertidal. This highlights the importance of evaluating the ecosystem services associated with Z. japonica, and how these compare to Z. marina and other nearshore habitats.

Session Title

The Role of Eelgrass Ecosystems in the Salish Sea

Keywords

Keywords: Eelgrass, Seagrass, Zostera, marina, japonica, Monitoring, Padilla Bay

Conference Track

Habitat

Conference Name

Salish Sea Ecosystem Conference (2016 : Vancouver, B.C.)

Document Type

Event

Location

2016SSEC

Type of Presentation

Oral

Contributing Repository

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

Comments

Keywords:

Eelgrass, Seagrass, Zostera, marina, japonica, Monitoring, Padilla Bay

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

This document is currently not available here.

Share

COinS
 

Long term monitoring of eelgrass, water and weather patterns in Padilla Bay, WA.

2016SSEC

The importance of eelgrass in nearshore ecosystem function and as an indicator of ecosystem health led to the establishment of a long-term monitoring program focused on tracking annual growth and distribution of eelgrass species (Z. marina and Z. japonica) in Padilla Bay, WA. This annual monitoring program was established in 2011 and consists of 126 permanent plots along three 4 km transects.

Eelgrass exhibits a complex response to environmental conditions driven primarily by temperature, light, and nutrients. Optimum growth requirements differ between Z. marina and Z. japonica, with the latter responding positively to warmer water temperatures and possessing an increased tolerance to high temperature extremes (Kaldy et al. 2015). Using long-term monitoring data from Padilla Bay, we investigated factors (i.e. temperature, light availability, water depth) that may help to explain patterns in eelgrass growth and performance. During the study period, we measured a two degree (°C) increase in mean water temperature, an increase in mean surface light (PAR millimoles/m2) and a decrease in mean water depth. Eelgrass measurements over the same time period reveal that the density and biomass of Z. japonica has dramatically increased, while Z. marina density and biomass have fluctuated over time with the lowest observed values in 2015.

These data suggest that the predicted increase in local temperature and sea level as a result of climate change may favor expansion of Z. japonica density and distribution, particularly in the upper and mid intertidal. This highlights the importance of evaluating the ecosystem services associated with Z. japonica, and how these compare to Z. marina and other nearshore habitats.