Opinion: BC needs to stop relying on insufficient, ineffective climate agreements

Written for Daily Hive by former Victoria City Councillor Alastair Craighead, Gulf Islands Raincoast Conservation Foundation’s forest project coordinator, Shauna Doll, and Raincoast Conservation Foundation’s Executive Director, Chris Genovali.

Forests, Large Carnivores and Climate Change

In the aftermath of COP26 and its myriad disappointments and unmet expectations, it is abundantly clear that it would behoove us to stop counting on insufficient, ineffective and compromised multilateral climate agreements. Instead, we need to start acting locally, and model climate leadership, by protecting British Columbia’s natural carbon sinks, such as our forests and wetlands. In addition, fostering ecological resilience in local ecosystems in the face of ongoing climate perturbations will be key to the future survival of BC’s fish and wildlife, and the well-being of British Columbians.

Our Local Forests and Wetlands are Natural Carbon Sinks

The Capital Regional District (CRD) on southern Vancouver Island and the Gulf Islands is a case in point. The CRD’s expansive Sea to Sea and Sooke Hills wilderness parks, and other contiguous protected forest areas, are crucial to the viability of the region’s ecological systems. They are also valuable in sequestering CO2, the most prolific anthropogenic greenhouse gas. This sequestration potential can be maximized by maintaining the biodiversity of these forests, including populations of large apex predators such as wolves, bears and cougars.

The combined protected forests in the CRD (about 34,000 hectares) sequester approximately 3.04 tonnes of CO2 per hectare annually for a total of 639,000 tonnes. To put that in perspective, the city of Victoria estimated its CO2 emissions at 356,000 tonnes in 2019. These numbers are estimates, but they demonstrate how important forests are in achieving climate stability. The CRD’s website indicates the identification of ecosystem services is at the planning stage. Also at the planning stage is a new “Long Term Strategy” for parks. Historically, strategic plans for CRD parks have prioritized maintaining ecological integrity, especially within parks still retaining wilderness or natural environments, as confirmed by the continued presence of ecologically influential species such as large predators. Resident surveys strongly support this approach to CRD park management.

Alex Harris/Raincoast Conservation Foundation

The Threatened Coastal Douglas-fir and Coast Western Hemlock Zones

The forests found in this region are representative of the Coastal Douglas Fir (CDF) and Coastal Western Hemlock (CWH) biogeoclimatic zones, 2 of 16 such zones in British Columbia. According to a 2020 article in the scientific Journal “Biodiversity and Conservation,” despite being some of the most biodiverse places in the country, these zones are also among the most threatened. They will require careful stewardship to protect them into the future.

The continued presence of apex predators within protected CWH habitats in the Sooke Hills suggests a diverse and balanced ecosystem. Conversely, most remaining CDF forests on Vancouver Island’s South Coast and across the Gulf Islands are fragmented with very few large carnivores. In the case of the Southern Gulf Islands, virtually no apex predators are to be seen, except for the very occasional, transitory cougar or black bear.

The Importance of Apex Predators for Healthy Ecosystems

Led by wildlife ecologist Dr. Justin Suraci, in collaboration with Raincoast Conservation Foundation, a study of Southern Gulf Islands ecosystems showed how the absence of apex predators has altered local ecology. One smaller meso-predator (a mid-ranking predator with less influence than apex predators), the raccoon, has run rampant on Southern Gulf Islands since the extirpation of large carnivores. In a clever experiment, the return of predators to the landscape was simulated by playing recordings of barking dogs. 

The results were dramatic. The raccoons became cautious and reduced their hunting time by nearly 70%. As a result, the numbers of four of their main intertidal prey populations more than doubled.

The relationship among predators, browsers like deer, and plants –including trees – is similar. On other Gulf Islands, a UBC study found that large predator loss increased the grazing intensity of deer. The resulting altered forest structure supports much reduced insect pollinator and songbird populations.

Alex Harris/Raincoast Conservation Foundation

Carnivores, Forest Structure and Carbon Sequestration

Due to a legacy of intense logging in what is now the Sooke Hills protected area, little old growth forest remains; many trees are reaching the age of maximum carbon sequestration, but will continue to store CO2. If the forests are allowed to mature, with apex predators in place, they will eventually develop old growth characteristics (provided climate change allows this to occur) and maximize the sequestration of many millions of tonnes of CO2 over the centuries to come.

In general, however, if large carnivores are lost, a forest’s structure will be altered due to an alteration of the usual trophic associations. Without predators to constrain populations of grazing mammals like deer, normal forest regeneration is inhibited and transformed due to over-grazing of tree seedlings and understorey plant species. In Scotland, the beautiful but barren moorlands, which cover most of the highlands, predominate because there are no apex predators to control deer populations. The reintroduction of wolves to Yellowstone to restore ecosystem balance is a well-known success story. In Scotland, there is a similar plan to bring wolves back in a rewilding process to restore some of the ancient Caledonian Forest. There is considerable public support for this conservation action.

Thankfully, in the CRD we are not in that place. Our last wild forests are not only refuges for large carnivores, but they are capable of great service in removing CO2 from the atmosphere. Forests are now valued as much for the carbon they sequester and store as for their biodiversity. With proper management, that much needed capacity will only improve.