Tree cover in Stanley Park has increased significantly since 2006 windstorm, study shows

A 10-year study by the Stanley Park Ecology Society (SPES) shows a significant increase in the tree canopy of Vancouver's biggest park, which, its authors say, highlights a recovery from the windstorm of 2006, when thousands of trees were destroyed.

"The tree cover is definitely a success story," said Arian Comeau, the conservation projects manager for the society, which runs programming in the park while also restoring habitat and monitoring wildlife.

On Wednesday SPES will present its 2020 state of the park report, which follows a similar one conducted 10 years prior.

The studies have been conducted to show how the park, which spans more than four square kilometres near downtown Vancouver, is coping with climate change, pollution and outdoor recreation use. 

Stanley Park is home to more than 1,000 native species of plants and animals, of which 46 are at risk, according the SPES.

The most positive highlight in the report about the park is its healthy tree growth since December 2006, when around 10,000 trees — up to 10 per cent of the park's total number — were lost in a major windstorm, when winds of up to 158 km/h hit B.C.'s South Coast.

Volunteers and others planted 15,000 trees and shrubs in blown-down areas to spur the recovery. Data from the five-year period between 2013 and 2018 shows an eight per cent increase in tree canopy in the park as a result of those trees being planted and others that naturally grew on their own.

Comeau says the gains are a significant marker of health for the forest in Stanley Park.

"It is very exciting," she said.

The health of bald eagles that live and breed in the park is also marker of the canopy recovery according to the report, as the birds require tall, strong trees for nesting.

In the last decade on average, one eaglet per active nest has been born, which is considered sustainable for the population, according to the report.

It also said that other bird populations in the park, such as woodpeckers, were healthier the less fragmented the forest was.

Lake issues, climate change

While the tree situation in Stanley Park is promising, the area continues to face challenges.

Freshwater ecosystems, such as at Beaver Lake and Lost Lagoon, which support frogs, salamanders, fish, beavers, bats, and birds are "doing poorly," the report found.

"Water temperatures are high in Beaver Lake and Lost Lagoon and oxygen levels are exceptionally low in Beaver Lake, to the point they are reaching lethal levels for salmonids and amphibians," said a release on the report.

Its authors found a low number of fish and amphibian species in Beaver Lake. 

"Without proper intervention, the situation is expected to worsen," it said.

Solutions include dredging Beaver Lake and creating habitat islands in the lake.

The report also laid out the challenges the park is facing from climate change, which include freshwater loss, erosion and sea level rise.

It's expected that sea levels will rise by a metre by 2100, which the report said will threaten the food chain for mammals and birds along the coast.

The City of Vancouver is exploring ways to adapt to these changes, such as creating more natural coastal shorelines.

Comeau says despite the challenges the park is facing, it's still very much a place of wonder and natural beauty.

She wants people to stay on trails when in the park to avoid disturbing plants and animals.

The SPES is also developing an online tool that will allow users to report on the biodiversity in the park so it can be better recorded.