I

During his initial field season in the Haida Gwaii archipelago, Matt Peck encountered a rocky island teeming with oystercatchers. The island was filled with thousands of these orange-billed seabirds, creating a lively cacophony of trills and squawks.

While tallying eggs on an islet located off the west coast of Canada, the scientists stumbled upon a peculiar nest made of twigs and grass tucked among the rocks. This led to a discussion among the group about which type of bird may have inhabited it.

Peck, a researcher from the Laskeek Bay Conservation Society, expressed their initial excitement and subsequent disappointment upon discovering the true identity of the nest. They described the sudden realization as a jarring blow that left them feeling disheartened.

The researchers briefly considered disposing of the nest, which was inhabited by a rat, as it symbolized the presence of a species that has become dominant on neighboring islands and has caused the death of countless birds in the last few decades.

“These islands are such a beautiful, inspiring place. And some of them were so special because they’re supposed to the last places in Haida Gwaii free of invasive species. You just felt for all these birds because you knew what was coming – and it was devastating.”

The Haida Gwaii archipelago, consisting of 150 islands, is facing a constant onslaught from invasive species that have the potential to disrupt the fragile ecosystem and diminish the diverse wildlife in the area.

The issue of invasive species is a worldwide concern that incurs a cost of $423 billion (£350 billion) annually. As communities strive to protect against these invaders, discussions about their elimination bring up broader considerations on the ability of ecosystems to evolve over time.

The group of islands, described by the Haida people as resembling a bear’s tooth, was created through repeated volcanic activity. According to geologists, parts of the archipelago were not affected by the most recent ice age, resulting in the survival of unique species found nowhere else, such as the world’s largest black bears and various subspecies of bats, ermine, and otters.

The vast variety of genes present in the environment is now facing a growing threat from unfamiliar predators. These predators pose a danger to the millions of native birds, eelgrasses, berries, and trees that have no natural means of defense against them.

On nearby Lyell Island, also known as Athlii Gwaii, 30,000 pairs of ancient murrelets, a species of auk, once nested on a single rocky outcrop.

However, rats have reached the population, consuming both eggs and chicks. As a result, there are now only a few remaining – a significant decrease that Peck describes as “unfathomable.”

“He mentioned how in the past, there were discussions about the sky turning dark as millions of ancient murrelets returned to their nesting sites,” he recalls. “However, that experience is no longer present.”

As the possibility of rain looms, Bobby Parnell carefully guides a small boat to shore near the town of Daajing Giids.

Their haul is pulsating inside two plastic bins: more than 1,000 European green crabs, also known as shore crabs, drawn from a single bay.

In the past 30 years, the invasive and aggressive crustacean has been spreading north in California, causing significant damage to clam beds and eelgrass ecosystems. These ecosystems are crucial habitats for young fish seeking shelter.

In the year 2020, crabs were observed in Haida Gwaii. Annually, the catch by local fishermen reveals the alarming rate at which they are taking over. In the previous year, approximately 30,000 crabs were caught from the sea. This year, with the fishing season still ongoing, over 200,000 have been captured. Parnell expresses, “It is distressing.”

The crabs have been observed in areas of the Tlell River that are over a mile away, which is a crucial area for salmon to spawn. This could potentially pose a threat to the local food chain and the crabs, which are considered a keystone species. The governing body, the Council of the Haida Nation, has granted multiple contracts to remove the crabs. The captured crabs are then frozen and crushed to be used as fertilizer.

Niisii Guujaaw, a marine-management planner with the Haida Nation, acknowledges that despite three years of dealing with the presence of crabs, they have yet to find a solution.

Local residents express concern that the current mobilization efforts, which resemble those during wartime, are not adequately funded and may be too late. Tyler Bellis, a forester and former council member of the Haida Nation, shares his feelings of hopelessness while out trapping crabs and observing the vastness of the bay, knowing that the crabs are present all throughout.

The Haida people see a parallel between the impact of invasive species on ecosystems and the vulnerability of their land to external influences. In the late 1800s, the population was decimated by smallpox outbreaks, reducing it from 30,000 to less than 600. The land and water resources have also suffered from colonization, including activities like logging, mining, fishing, and whaling.

The blacktail deer serves as a prime example of the destruction and intricacies caused by invasive species. Brought to Haida Gwaii as a source of food by Europeans in 1878, the population has since grown to almost 200,000 on the islands.

The deer have few natural enemies, as the bears are not interested in them due to their diet. As a result, the deer overgraze the land without much opposition. This has led to the disappearance of valuable medicinal plants that used to grow under the trees.

The Haida culture considers western red cedar saplings to be the “tree of life,” but unfortunately, deer have a strong preference for them. This has led to a lack of new cedars growing in the wild on many islands for many years.

In recent years, visitors have been attracted to the lush forests covered in dense green moss, which appears to be teeming with diverse plant and animal life. However, specialists argue that these forests are actually devoid of any significant biodiversity. The once dense understory, which made it challenging to navigate, has vanished.

In 2018, Parks Canada and the Haida community began a project called Llgaay gwii sdiihlda, also known as “restoring balance.” This initiative involved using sharpshooters and culls to eliminate deer on islands within the Gwaii Haanas nature reserve.

The attempt to eliminate the deer has evoked conflicting feelings among the residents, highlighting the integration of deer into Haida Gwaii.

According to Bellis, when the Haida population dwindled to just 600 individuals and faced the threat of extinction, access to quality food was essential. As a group that traditionally relied on seafood, the Haida have come to rely heavily on deer as a significant food source and an integral part of their culture.

Bellis has observed families bringing their kids to the land to learn how to hunt. However, he has also personally witnessed the damage caused by deer.

“I understand that not all invasive species are deliberately introduced. However, as a Haida who has already experienced so much loss, it truly hurts,” he expresses.

The islands possess distinct qualities and the animals who arrived or have remained here are truly extraordinary. It is disheartening to witness external invasive forces enter and harm much of this uniqueness.

On October 24, 2023, this article was updated. The previous version mentioned a smallpox outbreak in the late 18th century, but it should have stated the 19th century instead.

Find more age of extinction coverage here, and follow biodiversity reporters Phoebe Weston and Patrick Greenfield on X (formerly known as Twitter) for all the latest news and features

Source: theguardian.com