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Eelgrass—Nowhere to Hide

Bay Pipefish in Eelgrass

Bay Pipefish (Syngnathus leptorhynchus)–one of many species that depend on eelgrass habitat for survival.

A marine ecologist in Hart Crowser’s Anchorage, Alaska office, overheard a recent complaint, “When I go fishing I can’t stand all this ‘eelweed’ getting in my prop and fouling my lines.”

“Then why do you fish where there is eelgrass?” asked the marine ecologist.

“Because that is where fishing is best.”

That was the crucial connection. Eelgrass is essential fish habitat. Without it, even migratory fish (including our beloved salmon), don’t have a place to call home.

Eelgrass (Zostera marina) is native to shallow waters of most temperate oceans and seas, including Puget Sound, Oregon, northern California, British Columbia, and Alaska. It is not a seaweed like kelp, but a flowering plant that evolved from terrestrial flora (similar to what you might find in your front yard).

Eelgrass is important to many fish and invertebrates. Juvenile salmon, rockfish, and Dungeness crab find shelter in eelgrass meadows in early life. Herring, in particular, spawn on eelgrass, making it crucial to its survival. Many species (including commercially important ones) use it to live, eat, spawn, and hide from predators.

Eelgrass is also very good at converting carbon dioxide into tissue that may get buried, taking it out of the system (blue carbon). An acre of eelgrass can remove nearly 150 kg of carbon from the atmosphere every year, making it important to the issues of ocean acidification and global climate change.

Eelgrass is pretty hearty, dealing with coastal storms, being exposed at low tide, and spending part of each year under sea ice (in northern areas). Yet, as hearty and important as eelgrass is, it is on the decline, leaving fish and invertebrates that depend on it with nowhere to hide. Stay tuned for the reasons why, and what’s being done about it.

Ocean Acidification—What’s Being Done?

Ogasawara National Park

Our world’s oceans are becoming acidic nearly ten times faster than any time in the past 50 million years. This is because they absorb a percentage of the increasing amounts of carbon dioxide in the atmosphere; certain types of runoff can also contribute to the problem. Acidic oceans endanger marine life in many ways. For example, low pH seawater dissolves calcium carbonate, which is used to make shells.

The situation is especially dire for Puget Sound because of the way ocean currents work in our region. Since 2005, billions of oyster larvae in Puget Sound hatcheries have been decimated, resulting in significant loss in production and signaling profound impacts to Washington’s marine environment.

What’s being done about it? Over the last few years, a number of studies have been initiated both locally and around the world to understand the impacts and mitigate ocean acidification. A quick summary:

Washington State is a leader in taking action on ocean acidification. Former Governor Christine Gregoire created the Washington State Blue Ribbon Panel on Ocean Acidification, which convened February 2012. The panel created a report: Ocean Acidification: From Knowledge to Action (November 2012) and recommended 42 separate actions.

United States. The Federal Ocean Acidification Research and Monitoring (FOARAM) Act was enacted in 2009. Its purpose was to monitor and conduct research, establish an interagency research and monitoring program, establish a program in NOAA, assess impacts, and research adaptation strategies and techniques.

NOAA established its Ocean Acidification Program May 2011. The Interagency Working Group, which is chaired by NOAA, put out the Initial Report on Federally Funded Ocean Acidification Research and Monitoring Activities and Progress in Developing a Strategic Plan in March 2011. This report has a comprehensive outline for a Strategic Research Plan for Ocean Acidification.

World. The European Project on OCean Acidification was founded in 2008 and lasted four years. It had a consortium of 160 researchers from 32 institutes and 10 European countries. Although the project is over now, the website has a number of documents that may be downloaded.

While some important research has been done on the topic of ocean acidification, and some stopgap measures have been put in place (for example, to protect local oyster farms), we are a long way from solving this complex issue. The work has only just begun.

More information: Washington State Department of Ecology and NOAA.