Gorge Waterway
Wildlife and Plants
Extensive eelgrass beds are one of the most important biological features of the Gorge. These plants grow in soft sediment, and provide sheltering habitat for fish such as juvenile Pacific salmon and cutthroat trout. Herring use eelgrass beds for spawning, and deposit their eggs on the surfaces of the leaves. Decaying plant matter, called detritus, nourishes a complex food web of other animals.
Kelp is a marine brown algae that generally anchors to rocky substrate with a holdfast, and has leaf-like blades that float near the surface of the water. In the lower Gorge (below the narrows), kelp covers about 60% of the subtidal surface. The species present in this area is Laminaria saccharina. Kelp grows in areas where currents supply abundant nutrients. It provides habitat for fish and marine invertebrates.
Green algae, primarily sea lettuce (Ulva) is common among the eelgrass beds in the Gorge, and in shallow intertidal areas. Filamentous red algae (primarily Polysiphonia and Neogardhiella species) is most dense in the high current areas of the Gorge.
Intertidal gravel bars in the Gorge contain significant shell deposits, indicating the presence of littleneck and butter clams. Mussels (Mytilus species) are abundant in the high current areas of the Gorge, especially at the Narrows.
The native oyster (Ostrea lurida) is another important species found both in the Gorge and Portage Inlet. Historically, this oyster was an important food item for First Nations and non-aboriginal residents. Due to over-harvest, pollution and competition from invasive species, large native oyster beds are now rare on the west coast of North America. Native oysters are food for animals such as snails, limpets, sea stars and birds including white-winged scoters, black scoters and the greater scaup. Since they are filter feeders, oysters help to clarify the water of sediment and organic matter.
Rocky subtidal benthic communities are groups of plants and animals that live together on rocky areas of the ocean floor of the subtidal zone. They include aggregations of sponges, tunicates, bryozoans and cnidarians (e.g. anemones). Mussels, sea urchins gastropods (e.g. snails and limpets), and crabs are also common. Some of the largest such communities in the CRD harbours exist in the high current areas of Gorge.
Pacific herring spawn in the Upper Gorge, primarily in the eelgrass beds. People often jig for herring from the Gorge Bridge during spawning time.
Two streams that flow into Portage Inlet (Craigflower and Colquitz) support spawning populations of Coho and Chum Salmon, as well as Cutthroat Trout. Although they are much reduced from historic times, there are ongoing efforts to restore these populations. Juvenile fish shelter in eelgrass beds in the Gorge and Portage Inlet.
Brittle stars are echinoderms, and close relatives of sea stars. The species present in the lower Gorge is called Amphiodia urtica. It has been observed in populations of several hundred within half a square metre (0.5m2), buried in mud with only the tips of the arms exposed.
Birds
The Gorge Waterway connects Portage Inlet, one of the areas most heavily used by birds in the urban Victoria harbours, with Victoria Harbour, a federally designated Migratory Bird Sanctuary. The upper Gorge, between Craigflower bridge and Gorge bridge, supports numerous populations of resident and migratory birds. Species observed include Cormorants, Mallards, American Widgeon, Canada Geese, and diving ducks (e.g. Bufflehead, Greater Scaup and Canvasback). In the winter, diving ducks, mergansers and coots are the most common type of bird seen in the Gorge, whereas in summer and fall swans, geese and dabbling ducks predominate. The Gorge and Portage Inlet are two of the most important feeding areas in the CRD harbours for the Double-crested Cormorant (Phalacrocorax auritus), a Red-listed (endangered) species.
For more information about the relative abundance of various types of birds throughout the seasons in the Gorge, as observed in 1997-1999, see these graphs and tables. See also the seabirds, shorebirds and waterfowl section for general information about these birds in the Victoria area.
