What you should know about Garry oak savannas in Victoria

Lifestyle Sports | Lifestyle

Garry oak ecosystems are the exclusive home to hundreds of different species

Photo by David Stanley via Flickr.

Garry oak ecosystems are rare and highly degraded ecosystems that can be found almost exclusively on the southeastern coast of Vancouver Island and parts of the western United States. There are several locations throughout Victoria where you can find fragments of this once diverse ecosystem.

Garry oak ecosystems can come in the form of meadowed areas with dispersed trees or dense woodland, sometimes sharing space with other species of tree in the same stand. You’ve probably unknowingly walked through them if you’ve been to Uplands Park or Summit Park. They are known for their beauty, especially in the spring time — the mosaics of brightly coloured wildflowers bring the meadows to life. 

Prior to settler colonialism, the range of this biodiverse ecosystem was much larger. Over the last 150 years, the ongoing waves of settlers arriving on Vancouver Island has reduced the Garry oak savannas to less than 5 per cent of their former range. 

Habitat loss, fragmentation, industrial development, the consequences of fire suppression, and the encroachment of invasive species continue to threaten these valuable ecosystems. As residents of Victoria, educating ourselves about the species of this land can help us develop a more well-focused conservation ethic. 

Here are some essential things to know about this important ecosystem.

Cultural Importance 

For many First Nations communities in the region, Garry oak ecosystems have been intrinsically tied to their lives and cultures for thousands of years. In order to redirect succession, alter community composition, and maintain the fire-adapted ecosystems, First Nations would complete controlled burns of the Garry oak savannas. 

Colonial governments have prohibited the use of fire by First Nations to maintain ecosystems, and this ban has contributed to a decline in biodiversity in Garry oak ecosystems. Fire suppression has allowed species such as Douglas fir to shade out oak stands. As a result, conifers and shrubs inevitably crowd out the oak trees, wildflowers, and other species. 

While controlled burns are still prohibited, the necessity of it for restoration work is slowly being recognized, and BC Wildfire Service ordered the controlled burn of the two sites back in 2019.

While colonialism has displaced much of the flora and fauna in these ecosystems, many species still play an important role in many First Nation communities. Kwetlal, the Lekwungen word for camas, are plants that were cultivated and harvested for their bulbs in large quantities by Coast Salish communities; it represented a popular export as it was a primary source of starch for the people of the area. 

According to the UVic kwetlal restoration project done in 2014, the reintegration of kwetlal is essential for preserving traditional roles, responsibilities, and cultural identities for Coast Salish communities, which is why restoration projects focus on increasing the abundance and health of kwetlal. 

Biological Importance

The Garry Oak Ecosystems Recovery Team in Victoria reports on their website that “Garry oak and associated ecosystems combined are home to more plant species than any other terrestrial ecosystem in coastal British Columbia.” 

The website goes on to state that these ecosystems are home to over 100 bird species, seven amphibians, seven reptiles, 33 mammals, and 800 insect and mite species. Garry oaks are the only native oak tree in British Columbia. Many of these species occur only in coastal British Columbia and nowhere else in Canada.

Losing Garry oak ecosystems means losing these species. Over 100 Garry oak-associated species are at risk of extinction, which is why saving what is left is critically important. 

Invasive Species

One of the most significant threats that Garry oak ecosystems face are invasive species. Not all exotic species — species that are non-native — are invasive. To be invasive, an exotic species must become harmful to the ecosystem it has arrived in and outcompete the native species around it. There are plenty of exotic species in Garry oak ecosystems that are harmless, but there are several invasive species that pose major threats. 

If you go for a walk around Victoria, or even UVic, you will inevitably find invasive species encroaching throughout the area. Some examples include Scotch broom, gorse, English ivy, Himalayan blackberry, daphne, gypsy moths, and several invasive grasses.

The next time you think it’s pretty to see English ivy climbing up a tree, think again. That ivy is killing the tree. 

Restoration

Many stakeholders and organizations are dedicated to trying to save and restore Garry oak ecosystems. A few of these include the Garry Oak Ecosystems Recovery Team, Garry Oak Meadow Preservation Society, and the UVic Ecological Restoration Club. 

As settlers have played a major role in degrading and damaging this important ecosystem, many of these organizations recognize the responsibility that people have in reversing the devastation.

As the Garry Oak Ecosystems Recovery Team says on their website, “If we wish for future generations to be able to experience the richness and beauty of these natural areas, we must make an effort to maintain, and expand on, what is left of Garry oak ecosystems to the best of our ability.”