Wednesday 8 May 2013

Cowichan Garry Oak Preserve

These gnarled looking trees, with their twisted trunks and curious shapes are Garry Oaks.  Once widespread on southern Vancouver Island, their numbers have been diminishing steadily due to deforestation, climate change, invasive species, and disease. 

Garry Oak ecosystems are a complex structure of forest and meadow that provide a wide variety of habitat niches.  They support the highest diversity of plants in coastal British Columbia, and high diversities of insects, reptiles, and birds too.  

Less than ten percent of the original extent of Garry Oak ecosystems survives worldwide; bad news for the more than one hundred species at risk that depend upon them.  

Within the Cowichan Valley 20,000 to 40,000 acres of open Garry Oak meadow once existed.  There are now less than 100 acres and yet our area is known as one of the last and best havens for this globally endangered habitat.

Although we may perceive them as wild spaces, Garry Oak savannahs are actually the product of careful management.  For more than 4000 years here in the valley, Cowichan First Nations cared for this ecosystem through controlled burning.  Fires ensured that the grasslands would continue to flourish instead of becoming overgrown with brush, and then forest. Thanks to this mindful management, the fertile grassland topsoil in our Garry Oak meadows extends as deep as three feet in some places.

Here in Cowichan we have a Garry Oak Preserve, on land purchased in 1999 and 2001 by Nature Conservancy Canada. Within the preserve a concerted effort is being made to restore the Garry Oak meadows to what they might have been prior to European settlement.  Invasive species are being removed, controlled burning is being used to restore the grasslands, and plants are being grown in an on-site nursery for the purpose of reestablishing them within the savannah.

Among the plants being reestablished at the Garry Oak Preserve are forty-five red listed species; plants that are in danger of completely being completely extirpated from the local ecosystem.  It is the hope of the scientists, naturalists, and volunteers who work at the preserve that, in caring for the Garry Oak meadows and planting these nursery plants, the ancient balance of flora and fauna in this area may be restored.  

Scientists from across North America come to the Garry Oak Preserve to study the complex ecosystem.  Much of their work contributes to efforts by Nature Conservancy Canada and other organizations working to re-establish Garry Oak ecosystems throughout their range.

For those of us in the valley, the Garry Oak Preserve provides an opportunity to enjoy walking trails, dappled shade, and beautiful scenery. While we walk and enjoy, we also learn about the many plants and animals the area supports.  It's a beautiful place - both quiet and bursting with life at the same time - and it affords us a glimpse into the area's ancient past.

If you would like to learn more about the Garry Oak Preserve, you can read about it on the Nature Conservancy Canada website and you can also enjoy an informative video narrated by site manager Irvin Banman.