Thriving Worm Population Discovered in the Arctic

Worms are encroaching on new territory in the Far North, causing concern among people. This region has been free of worms since the last ice age, and their proliferation will inevitably lead to changes in northern ecosystems. These changes have implications for the entire planet, with consequences that are not yet fully understood and likely irreversible.

It is important to approach this situation with caution, as removing these organisms will be challenging. Therefore, a thorough study of their effects is essential. Jonatan Klaminder, an ecology professor at Umea University in Sweden, emphasizes the need for careful research into the consequences of these organisms.

In most temperate regions, the presence of earthworms is a positive sign, indicating healthy soil packed with flora, fungi, and beneficial bacteria. Earthworms contribute to soil health by consuming decaying organic matter and enriching it with nutrients.

However, the introduction of worms into Arctic and sub-Arctic zones can disrupt the natural balance of ecosystems. They can alter food webs, promote the growth of certain plants while suppressing others, and further endanger already threatened native flora.

Dr. Klaminder points out that, locally, earthworms have a more significant impact on vegetation than temperature. Additionally, they can stimulate microbial activity that releases potent greenhouse gases stored in the soil, such as carbon dioxide, methane, and nitrogen.

Humans have played a role in the spread of worms to these regions, intentionally or unintentionally. Importing soil for lawns, gardens, and fishing bait has brought worms to remote areas above the Arctic Circle and sub-Arctic regions since at least the 1800s. The increase in travel to these areas has also contributed to their invasion.

As climate change accelerates and the permafrost thaws, worms are finding new habitats in the Far North. Once established in the soil, they can reproduce without a partner due to their hermaphroditic nature.

The changes caused by worms can favor the growth of grasses and shrubs over tundra mosses and lichens. While this benefits certain animals like lemmings and voles, other herbivores may struggle to adapt to the change in their food sources.

Moreover, these changes can disrupt the reflective properties of snow cover, leading to increased heat absorption by the ground. Similar transformations have been observed in temperate and boreal forests in North America, where worms have facilitated the growth of grasses and herbs at the expense of trees.

The overall impact of these worm invasions on global ecosystems and greenhouse gas levels remains uncertain. The multitude of effects they cause makes it challenging to predict the outcome. Lee Frelich, director of the Center for Forest Ecology at the University of Minnesota, highlights the variability among impacts depending on the context.

Initial research suggests that the overall impact on the planet’s carbon balance may range from zero to a net reduction, depending on the vegetation type. While worms release carbon dioxide through the decomposition of organic matter, they can be offset by plants absorbing carbon from the air. However, some experts argue that any positive effect on the carbon balance could be negated by the decline of tree growth in North American forests.

What is certain is that these changes caused by worms are significant, occurring rapidly in a region that is experiencing accelerated warming. The Far North harbors some of the last untouched ecosystems and vulnerable species. The irreversible nature of these changes coupled with the difficulty of eradicating worms raises concerns. As the Far North becomes more hospitable, settlements are likely to expand, further impacting the region.

Dr. Klaminder emphasizes the need to assess the scale of the problem in the Arctic, as this region remains one of the few pristine areas untouched by human settlements.