Marine Riparian zone of nearshore

The marine riparian is sometimes called the uplands. It consists of the shrubs and trees that provide important services to the nearshore and the fish, animals and birds that live there. These services include:

• Shade
• Insects
• Wrack line

Like other areas of nature, the native plants provide many services. Invasive plants however can push out these important native plants, and so prevent the nearshore from working as it should.

Shade vital for food chains

The shade provided by shrubs and trees in the marine riparian zone is vital to the survival of Surf Smelt, an important part of several food chains in the nearshore. The Smelt spawn in the upper intertidal and so the eggs are exposed to the hot sun. With shade to keep them cool, the eggs can survive. Without shade from the marine riparian, the eggs can bake in the sun and die.

Insects key to salmon survival

The shrubs and trees that hang over the high tide provide insects to fish in two ways. First are those insects that drop into the water from the trees. Second are those insects that spend time in the cool shade and fly over the water, to be grabbed by the fish. This source of insects has been shown to be vital to the survival of Chinook and Coho salmon, and Cutthroat Trout

Invasive plants spreading in marine riparian

Many people that live along the water introduce plants into the nearshore without realizing it. We know from seeing what has happened in Washington State and other locations that several plants that we grow in our gardens can actually take over estuaries and nearshore ecosystems. When this happens the habitat (food and homes) of several native birds and animals disappears, and the ecosystem can’t work properly. It is important to remove invasive species and re-establish native plants.

How plants are introduced

• Some have a seawall and toss their lawn and garden clippings over into the ocean, thinking it will be taken away. The currents however can carry these plants to other locations where they start themselves.
• Other landowners have gardens planted along the edge of the backshore, or replace the backshore with a garden. Invasive species will spread into the nearshore by rhizome, seeds, or clippings.

Plants to remove

MVIHES mapped the vegetation in the Englishman River Estuary and found several key species that need to be managed. We also created an initial visual tool re health of the marine riparian. The list below is based on this mapping work.

There are many invasive plants on the coast and other sources will provide detailed information.

Plants to remove here include:

• English Ivy
• Herb Robert
• Yellow Laminarium
• Scotch Broom
• Periwinkle

The Groundwater Mapping and Education Project began last year on a small scale and the report of that first phase is available here. The second phase will continue from Phase I by defining the location and geometry of the sand and gravel aquifers in the lower section of the Englishman River down to the estuary.

The project is being led by groundwater expert, Dr. Gilles Wendling, Hydrogeologist, and will provide:

1. Characterization of the aquifers (GIS): Vancouver Island University (VIU) will detail the interpretation of the subsurface in the ER watershed and generate detailed maps and cross-sections of interpreted aquifers and assumed water tables;
2. Piezometric Assessment: Up to 20 data loggers will be installed in private wells located in aquifers to be characterized. The data loggers will record the fluctuations of the water table elevation;
3. Characterization of the Surface Water Flow: Up to 10 gauging stations will be installed along the ER to collect information on surface water elevation, flow rate, and temperature. The gauges will be installed and regularly monitored by volunteers;
4. Data Interpretation: With the newly collected information, GW Solutions and VIU will define a conceptual model describing where the aquifers are, how they connect to the ER, and the water flow between the aquifers and the ER.
5. Public Education and Involvement: MVIHES will inform the public of the project through the local media, public presentations, displays and direct contact. It will interview local residents and seek their cooperation in voluntarily monitoring their wells. This public communication will be enhanced with the on-going public outreach conducted by MVIHES, which focuses on watershed protection and water conservation.

This project has been made possible with funding from RBC Blue Water Project, Real Estate Foundation of BC, and the Regional District of Nanaimo