Thursday, 3 December 2015




Located in the Coastal Western Hemlock biogeoclimatic zone, in the 1,528 hectare Juan de Fuca Provincial Park, Sombrio beach is a haven of biodiversity. One of 4 trailheads to the Juan de Fuca trail on the western side of Vancouver island, This stretch of rocky coastline is a wilderness destination, and is one of four trailheads to the Juan de Fuca marine trail. Visitors can camp, explore tidal pools, surf and take advantage of bouldering spots. The Juan de Fuca provincial park is a protected area, and is a corridor for many large vital mammals such as otters, deer, cougars, black bears and wolves (Juan de Fuca zoning plan, 2015).

Geomorphology



Sombrio beach is located on the active Cascadia subduction zone where the Juan de Fuca and North American plates converge. (Mosher et al. 2004).  These first order processes (Klee, 1999) such as widespread faulting are present at this site with deep, rugged mountain terrains carved out by the Cordilleran glacier that dominate the coastal area near this boundary (Alley and Chatwin, 1979). With ice sheets ranging in thickness from 1000m to 450m from Victoria to the edge of the Juan de Fuca Strait, the ice sheet was integral to the formation of features including the splitting of the Puget and Juan de Fuca lobes (Alley and Chatwin, 1979). This rugged terrain consists of pre-tertiary igneous rock and metamorphosed limestone (Alley and Chatwin, 1979). With these defining features of a narrow continental shelf, a rugged shoreline and deep basins that result in small, fast running streams, this tectonically active site is indicative of a leading edge coastline (Klee, 1999). Wind exposure, high energy waves and powerful storm surges slowly erode the rugged, rocky shore. Evidence of this erosional process is seen in beach cobble consisting mainly of island lithology (Alley and Chatwin, 1979) with finer grains deposited along the southern portions of the beach through longshore drift (Klee, 1999). Steep berms at swash zones and the movement of large logs provide further evidence of high energy waves along the shoreline; while boulders deposited via glaciation processes along the intertidal and breaker zones depict a rocky, reef dominant benthic environment (Alley and Chatwin, 1979) that provides a steady surf with both ground and wind swells influenced by North Eastern winds (surf forecast).

Rocky Shores

Situated in the Juan de Fuca strait, Sombrio is susceptible to strong ocean currents that flow from North to South, creating longshore drift. Sombrios cobble beach also experiences beach drift, and with these combined effects create steep berms in the swash zone.
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Photo received November 12th, 2015 from: https://www.crd.bc.ca/education/our-environment/ecosystems/coastal-marine/intertidal-zone


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Being a leading edge rocky shoreline, sombrio is subject to vertical zonation which can be seen with the distinct brown algal, red algal, and subtidal zones. Sombrios backshore consists of a Douglas Fir, Coastal Western Hemlock forest with a rich understory of salal, oregon grape, deer fern and huckleberries (What is the intertidal zone? 2015).
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Sombrio experiences diurnal tides, in October seeing changes of almost 10 ft.
tide graph for Sombrio Beach surf break

Biophysical Communities



Being a leading edge rocky shoreline, sombrio is subject to vertical zonation which can be seen with the distinct brown algal, red algal, and subtidal zones. Sombrios backshore consists of a Douglas Fir, Coastal Western Hemlock forest with a rich understory of salal, oregon grape, deer fern and huckleberries (What is the intertidal zone? 2015).
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The nearshore consists of a cobble beach, where outdoor enthusiasts can set up campsites or start a hike on the Juan de Fuca trail.  The intertidal zone is home to many creatures that have adapted to withstanding the harsh environment of being inundated between tides (What is the intertidal zone? 2015). The intertidal zone is also home to tide pools that can be some of the most diverse small scale ecosystems, and holds creatures such as barnacles, urchins, anemones and chitons (Intertidal Zone, 2015). Between the intertidal and subtidal zone, eelgrass communities create a keystone habitat, which are currently endangered on BC and global coastlines.


In the subtitdal zone Sombrio has dense kelp forests that create a unique environment for different invertebrates, and are also an important food source for many organisms such as sea urchins. Kelp forests help create a safe buffer zone on the wave dominated shoreline. Protection from the high wave energy in this area is important for different small larval fish (Suzuki Foundation, 2015).
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An individual kelp plant alone can house over 10,000 separate invertebrates, such as crabs and snails (Suzuki Foundation, 2015). Kelp is important in the life cycles of juvenile rockfish, of which several species are threatened by by-catch (Suzuki Foundation, 2015) .

Eelgrass


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Sombrio beach has several fresh-water tributaries, the largest one being Sombrio creek. This creates an environment of brackish waters, which eelgrass thrives in. Eelgrass meadows can be seen inundated between the intertidal and subtidal zone during low tide, in between the rocky headland called Sombrio point and minute creek. Eelgrass is dependant on water clarity, temperature, light attenuation, salinity, and pH (Wright, 2002).

Eelgrass are home to many microbes that break down dead plant matter that create primary nutrients for many species that exist in these communities. This flourishing ecosystem creates a sheltered habitat for many organisms at different crucial times in their life cycle, such as juvenile Pacific salmon, herring, pipefish and smelt. It is also home to many kinds of invertebrates including sea stars, clams, sea urchins, crabs and snails (What is eelgrass? 2015). There are also mammals that are part of the eelgrass communities like harbor seals and river otters, as well as epiphytes that depend on the eelgrass for habitat.
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Eelgrass at sombrio is threatened by heavy storms that can pull the eelgrass from its substrate, and sediment runoff from natural sources and deforestation that reduce clarity in the water (What is eelgrass? 2015). Eelgrass is not only important for biological communities but for human activities as well, as eelgrass prevents beach erosion, and is a carbon sequester. It is important that eelgrass meadows are conserved, as they are a center of biodiversity and fundamental to many organisms (Wright, 2002).

First Nations Importance


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Traditional territory of the Ditidaht and the Pacheedaht first nations, Sombrio beach has a diverse history. With territory ranging from Cowichan to Pachena Bay, including marine harvesting sites and a village site at Sombrio Beach, the Ditidaht and Pacheedaht tribes considered themselves rich with food and land (Our History and Culture). Sacred to these tribes is a hidden waterfall up a creek at Sombrio beach (Naylor, 2014). Though their tetrritory was large, property rights were fiercely guarded, highlighting the attachment the people had with their environment (Our History and Culture). Upon James Douglas's arrival to Vancouver Island, he estimated there to be 539 aboriginals in the area. Though the people worked with the Hudson’s Bay Company, oral stories of Europeans raiding and killing off of entire villages resulted in the amalgamation of separate tribes into family groups (Our History and Culture). These groups were eventually displaced to reserves; however, as they did not receive the opportunity to negotiated a treaty, these reserves were not within traditional village sites and by 1914 there were only 155 peoples of the Ditidaht tribe (Our History and Culture). Though populations have increased, the effects of displacement and the loss of the communities sense of place has resulted in high poverty rates within the indigenous community. Upon development of the Juan de Fuca Marine Trail, the Ditidaht and Pacheedaht tribes gained a level of authority as they negotiated a treaty with the Government of British Columbia that included an initiative to protect coastal land within traditional territory (Ditidaht First Nation and Pacheedaht First Nation Amended Framework Agreement, 1997).

Human Interaction



As first nations tribes were displaced from their territory, other human interactions have occurred in or near Sombrio, including logging, mining, fisheries and a vibrant squatters community. This squatter's community developed in the 1960’s and included a family with eleven children and a herd of goats. Living in a cedar cabin next to Sombrio creek, this family lived within their community with “a sense of place [that brought] together … creativ[ity] … away from the consumer world”(Manly, P. 2006). Living in connection to the natural resources on the beach, the squatters called Sombrio home until 1997 when they were evicted from the beach by the government (Hawthorne, 2006). As the beach was included in the protected park area, government workers were employed to destroy the makeshift homes along the beach (Manly, 2006). Displaced to the town of Port Renfrew, this family struggled with integrating into the community and by 2011 had lost three of their eleven children via accidental deaths (Hawthorne, 2011). As Sombrio’s squatters, including this family, struggled with loss of their connection to place, the integration of Sombrio beach into park land increased access to the space for many other users. With two camping sites along the beach, Sombrio has become a popular destination for campers, hikers and surfers alike. 

Photos retrieved November 3rd 2015, from: http://manlymedia.com/films/sombrio/