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Ensuring the Survival of Native Plants Amid Climate Change

In the United States, numerous native plant species face the threat of extinction driven by climate change, with the ability to adapt to shifting environments moving too slowly to ensure their survival. For these species to endure, they may require human intervention to relocate to suitable habitats nearby, a process referred to as “managed relocation.” However, this practice carries significant risks, including the potential for introducing new invasive species, a scenario that has already led to ecological imbalances across various ecosystems.

Recent findings from ecologists at the University of Massachusetts Amherst shed light on the characteristics of plants that are crucial for successful relocation while minimizing adverse ecological impacts. “The imperative to relocate species arises from climate change,” explained Thomas Nuhfer, the study’s lead author and a graduate student in organismic and evolutionary biology at UMass Amherst. “However, the concern among those managing invasive species is valid; we don’t want to inadvertently create further problems by moving native species into new locations.”

Invasive species have posed challenges in the past, with examples like kudzu overgrowing forests and wetlands dominated by purple loosestrife. “Historically, introducing non-native species has resulted in negative consequences,” noted Bethany Bradley, a professor of environmental conservation at UMass and the paper’s senior author. “At the same time, failing to act in the face of climate change may lead to even greater ecological harm.”

Research from Bradley’s lab highlights that addressing the issue of invasive species is vital for local climate preparedness. Findings indicate that invasive plant populations are proliferating rapidly, with biodiversity needing to shift its range by approximately 3.25 kilometers each year to cope with rising temperatures and corresponding ecological changes.

So, how can we effectively aid the relocation of plants while minimizing the risk of them becoming invasive?

According to Nuhfer, assessing certain plant traits—such as growth rate, flowering duration, and seed dispersal mechanisms—can inform both the likelihood of a species becoming invasive and its potential success in a new environment. “These traits, which often predict invasiveness, also contribute to the survival of native species during relocation,” he noted.

To determine which characteristics foster successful relocation versus invasive tendencies, Nuhfer and Bradley analyzed a wide array of literature on restoration, invasion ecology, and existing plant risk assessments. They discovered that the traits advantageous for establishing new populations, whether in invasive or relocation contexts, overlap significantly. However, the subsequent impact on local ecologies varies greatly between invasive species and those successfully relocated.

A trait such as a high metabolic rate benefits a plant’s establishment across both categories. In contrast, size may favor not just successful establishment but also rapid and expansive growth that disrupts the new environment. Additionally, traits like toxicity serve as indicators of less suitable candidates for relocation, as they assist in spreading and can cause ecological harm without enhancing establishment potential.

This research proposes a reevaluation of how we assess risks associated with relocating native species. Instead of excluding traits like rapid growth or widespread seed dispersal, risk assessments should focus on identifying characteristics that do not facilitate establishment—such as toxicity—that may lead to invasive behavior post-relocation.