Extreme weather may help nonnative animals replace native ones: Research

Extreme weather linked to climate change may displace native species and benefit nonnative or invasive ones, according to research published Monday in the journal Nature Ecology & Evolution.

Researchers from the Chinese Academy of Sciences analyzed more than 440 studies, which researched how 1,852 native species and 187 nonnative species responded to extreme weather. Among the species, which spanned land, freshwater and oceanic habitats, nonnative species tended to be better positioned to endure extreme weather events than their native counterparts.

For example, native land species are vulnerable to cold snaps, droughts and heat waves, while their nonnative counterparts are only particularly vulnerable to heat waves. Similarly, native freshwater species are vulnerable to most weather phenomena except extreme cold, while nonnative species are for the most part only susceptible to extreme storms. 

The specific effects on animals also varied by native or nonnative status, according to the research. The analysis found that extreme weather events are associated with declines in abundance, body condition, distribution and recovery in native land species, versus only low abundance in nonnative species. 

The effects of climate change have been linked to invasive species before. The connection has been particularly notable in the Colorado River, which serves multiple states in the western U.S. Warming river waters have been linked to a number of invasive species, particularly the smallmouth bass, which scientists see as a potential threat to the Grand Canyon region’s ecosystem. For two consecutive summers, the National Park Service has removed smallmouths and another species, the green sunfish, from the Colorado River Slough below the Glen Canyon Dam. 

A September report by the United Nations’ Intergovernmental Platform on Biodiversity and Ecosystem Services indicated that human activity has caused the introduction of over 37,000 species worldwide, and that these introductions cost $423 billion globally in 2019, a monetary figure that has steadily increased every decade since the 1970s.