The Great Invasion of Canada’s Pacific Coast

Haida Gwaii, a remote archipelago off Canada’s Pacific coast and home to the Indigenous Haida people, faces a severe ecological threat due to invasive species. Once filled with the sounds of orange-billed oystercatchers, the islands now contend with the overwhelming spread of non-native animals, particularly rats, European green crabs, and blacktail deer. The Haida are actively working to protect their land, as these invasive species disrupt the native ecosystems that have supported both wildlife and the Haida culture for generations.

An Ecosystem in Peril

The Haida Gwaii archipelago, often called the “Islands of the People,” comprises approximately 150 islands renowned for their natural beauty and biodiversity. The islands host unique subspecies of animals, including the world’s largest black bears, specialized bats, ermine, and otters. However, invasive species are rapidly eroding this biodiversity. Rats prey on native birds, European green crabs decimate critical marine habitats, and blacktail deer overgraze native plants, collectively putting immense strain on this ecosystem.

Rats: The Silent Invaders

First introduced to Haida Gwaii from European ships, rats have become silent predators within the ecosystem. During an egg-counting survey, researchers discovered a rat’s nest among the rocks, highlighting a threat to local bird populations. Rats consume the eggs and chicks of nesting birds, and their spread has decimated populations of ancient murrelets (Synthliboramphus antiquus), which once numbered 30,000 pairs on Lyell Island but are now nearly extinct. Originally found in the northern Pacific, from Alaska to Japan, ancient murrelets depend on undisturbed island habitats to breed.

European Green Crabs: Marine Ecosystem Disruptors

The European green crab (Carcinus maenas), an aggressive species native to European and North African coastlines, was introduced to North America’s Pacific coast over thirty years ago. Since then, it has rapidly expanded northward, arriving in Haida Gwaii in 2020. This small but destructive crab preys on clams, mussels, and eelgrass beds, crucial habitats for juvenile fish and shellfish. With over 200,000 crabs trapped in Haida Gwaii in a single year, the scale of their spread signals a dire threat to local marine ecosystems.

Blacktail Deer: An Unchecked Population

Introduced by European settlers in 1878, the blacktail deer (Odocoileus hemionus columbianus) has flourished in Haida Gwaii’s forests without any natural predators. Originating from the temperate forests of North America’s west coast, blacktail deer have reached a population of nearly 200,000 on the islands. Their unchecked grazing damages native vegetation, depleting medicinal plants and halting the growth of western red cedar (Thuja plicata), a tree deeply significant to Haida culture.

An Ongoing Battle Against Invasive Species

To counter the damage wrought by invasive species, the Haida have implemented measures to remove or control these populations. Contracts for crab culling have been issued, with captured crabs repurposed as fertilizer. However, the Haida report that their conservation efforts are under-resourced and face significant challenges due to the scale of the invasion.

A Difficult History

The struggle against invasive species resonates with the Haida people’s own history of vulnerability to outside forces. In the 18th century, smallpox epidemics reduced their population from approximately 30,000 to fewer than 600, and waves of colonial exploitation—from logging to mining and commercial fishing—profoundly altered their lands. Today’s ecological threats present new challenges, as they continue to fight for the survival of both their culture and their environment.

Preserving the Haida Gwaii Landscape

Haida Gwaii’s unique landscape has long attracted visitors drawn to its dense, moss-covered forests and vibrant wildlife. However, beneath the surface, invasive species have devastated the forest understory, transforming once-lush landscapes into barren areas. The Haida’s efforts to protect their ecosystem highlight both their resilience and the broader global challenge of managing invasive species.

Protecting Haida Gwaii’s Future

As Haida Gwaii battles the ecological consequences of invasive species, the dedication of the Haida people stands as a testament to resilience and a commitment to future generations.