Garry Oak Ecosystem Conservation

Ecology

Garry oak (Quercus garryana) ecosystems, like many oak ecosystems, have a good ecological range. these ecosystems can range from denser woodlands to more open fields and meadows with trees dotted throughout. Western red cedar, Western hemlock, Shore pine, Arbutus and Douglas-fir can be found with Garry oaks in mixed stands, with a plenty of flora living under their shade.(10) Mosses, wild flowers, shrubs, fungi, lichen, and grasses all flourish in these ecosystems (Garry Oak Ecosystem Recovery Team). Garry oaks live in areas with mild winters, and tend to be on coastal areas in the pacific northwest.(10)  Even though Gary oaks themselves are not on the endangered list, several of  the ecological communities they support are on the BC provincial red list.

Threats

Garry Oak ecosystems are very unique especially in the Pacific North West, nevertheless they have faced many obstacles and are in decline. For instance it is known that these ecosystems has been reduced 95% in the last 150 years. This sharp decline in a short amount of time is contributed to three main process of habitat loss, fire suppression, and invasive species.

Habitat Loss

When considering habitat loss, large scale development of these ecosystems does harm these ecosystems and is usually first considered especially the with past history of development being for industrial, residential, and agricultural purposes.  Especially since this is a very common pattern to have naturalized areas be converted to industrial places or farmland, which seen in many different parts of the world. Even on a global scale agricultural land area is approximately 38 percent of global land allocation. However, one of the less known aspects of habitat loss is habitat fragmentation, and is a huge driver in why Garry Oak ecosystems are declining.  This habitat fragmentation is when larger areas of habitat get separated/changed into vulnerable patches that are much smaller. Essentially after this fragmentation occurs, it allows for other threats to enter the scene. such as woody species of plants or invasive species, which can further assist in habitat fragmentation. This mechanism has occurred continuous to this day, where now less than 5% of these ecosystems are left in near natural conditions.

Fire Suppression

Indigenous peoples of coastal British Columbia historically were part, and still are to this day part of many ecological communities. In many ways, they  were a crucial aspect to these ecosystems, with Garry Oak ecosystems being of no exception. Recent studies show paleo-ecological evidence and anthropological evidence that in the late holocene there was maintenance of the open savannah habitat even thought it was a colder and wetter climate. Historical and ethnographic evidence points to repetitive and purposeful use of fire by Coast Salish Peoples.  Considering historical maintenance by fire, this suggests that Garry Oak ecosystems have a very long history of indigenous management.  Incidentally, when overlooking how this ecosystem started changing, it correlates with colonization done by early European settlers. Fire suppression can occur in a physical matter but can also be implemented on a policy level.  Especially when disturbance regimes drastically changes, Fragmentation occurs on the physical level. Allowing for woody species of plants (whether being invasive or native species) like douglas firs and other shrubs to invade this prairie ecosystem. this ultimately shades out the Gary Oaks, Wildflowers, eventually replacing them and the ecosystem itself and how it functions, stopping fire from being a functioning aspect of the ecosystem. Whereas, even in policy, traditions and practices of indigenous people were criminalized. As seen, not only is there a physical barrier, but there is additionally policies acting as a barriers. Due to these barriers, this maintaining this ecosystem is physically stunted or even outlawed which causes fire suppression in Garry Oak ecosystems.

Invasive Species

Currently, many of the fragmented Garry Oak ecosystems have a dominance of introduced species, typically being invasive species. An Invasive species is a organism that has been introduced to a naturalized area, will spread itself throughout the ecosystem and negatively change the ecosystem. The fragmentation of these ecosystems is often what allows for the easy entry of many of these invasive species. Below is a table of some of the major invasive species seen within Garry Oak Ecosystems, and their impacts on Gary Oak ecosystems.

Species/Genus	Impacts on Ecosystem
Scotch broom (Cytisus scoparius)	invades sunny, disturbed rangeland can increase the intensity of wildfires can produce seeds that can survive in the soil for 30 years
Gorse (Ulex ssp.)	thrives within infertile highly disturbed can live up to 45 years can spread over 18,000 per plant fire hazard
English ivy (Hedera helix)	commonly planted commercially for houses and walls spreads easily, and even grows in layers suppressing native plants needs little light or water to establish, even grows in winter
Himalayan blackberry (Rubus armeniacus)
Spurge Laurel (Daphne laureola)
Eastern Grey Squirrels (Sciurus carolinensis)
European starlings (Sturnus vulgaris)
Gypsy Moths (Lymantria dispar)
Kentucky bluegrass (Poa pratensis)