An international team of scientists, led by researchers at the University of Massachusetts Amherst, has determined that non-native species are expanding their ranges at a much faster rate than native species, largely due to human assistance. Non-native plants, even those that appear stationary, are moving three times faster than native plants as they race to adapt to the rapid pace of climate change. To survive, plants and animals must shift their ranges by 3.25 kilometers per year to keep up with rising temperatures and changing habitats, a feat that native species cannot accomplish without human intervention.
The team, which includes scientists from various locations in the U.S. as well as Spain, conducted an extensive survey of previously published papers and datasets to determine the speed and distance at which both native and non-native species are moving. They found that non-native species are spreading at a rate of 35 kilometers per year on their own, but this rate jumps to 1,883 kilometers per year when human involvement is considered. In comparison, native species are only moving at an average rate of 1.74 kilometers per year, highlighting the significant advantage that non-native species have in response to climate change.
Humans play a crucial role in accelerating the spread of non-native species, whether inadvertently through international trade or intentionally through the purchase and transport of invasive plants. This human assistance has led to non-native species outpacing native species by a factor of 1,000 in terms of spread rate. It is becoming increasingly clear that without human intervention, native species will struggle to keep up with the pace of climate change, putting them at risk of extinction as their habitats become increasingly unsuitable.
In addition to understanding the current speed at which species are moving, the team also investigated how far both native and non-native species might spread in a warming world. While non-native species may have more territory to gain with climate change, they also face the risk of losing territory as some range margins become unsuitable. As a result, the researchers emphasize the importance of implementing assisted migration, a practice that involves deliberately helping native species move to more suitable locations, in order to give them a fighting chance against the threats posed by non-native species and climate change.
The findings of this research highlight the urgent need for proactive conservation efforts to protect native species from the threats posed by non-native species and climate change. By understanding the speed and extent to which species are moving, as well as the implications for their future survival, scientists can work towards developing strategies to assist native species in adapting to a changing environment. Ultimately, the success of native species in the face of these challenges will depend on the collective efforts of researchers, policymakers, and the public to prioritize conservation and support biodiversity conservation initiatives.