A recent study suggests that climate change may be making it easier for invasive species—organisms that are not native to a particular area but have been introduced by humans—to thrive. Researchers analyzed 67 studies on 30 marine invasive species and found that climate change generally increases their abundance or ability to establish themselves in new environments. However, the extent of this effect varies depending on the species, local environmental conditions, and the design of the study. One notable example of this phenomenon occurred after Hurricane Maria in 2017, which hit Puerto Rico with winds of up to 250 kilometers per hour (155 mph). The storm caused widespread damage to both human infrastructure and natural ecosystems, including the destruction of native seagrass meadows and a significant decline in forest bird populations. In the aftermath, the invasive seagrass Halophila stipulacea, originally from the Red Sea and Indian Ocean, quickly recovered and spread throughout the Caribbean. This species was introduced to the region through human activities and has the potential to alter local fish communities that depend on native seagrasses for shelter. Invasive species are non-native organisms that can spread rapidly and disrupt local ecosystems. For example, the brown tree snake was accidentally introduced to Guam, where it led to the extinction of 13 of the island’s 22 native bird species. Similarly, the non-native smooth cordgrass was brought to China in 1979 to stabilize shorelines but eventually transformed tidal mudflats into dense salt marshes, altering local ecosystems and biodiversity. While climate change may not have caused Hurricane Maria, extreme weather events like it can damage native ecosystems and create opportunities for invasive species to spread. For instance, a marine heatwave in the Northeast Pacific from 2019 to 2021 lasted nearly 1,000 days and was much more intense than usual. Scientists estimate that such an event had less than a 1% chance of occurring without the influence of elevated greenhouse gas levels. The study found that while climate change can increase the abundance and establishment of invasive species, it rarely promotes their spread. This may be due to the stage of invasion—some species may grow in number but fail to establish themselves if environmental conditions are not ideal for reproduction or if their growth depends on a continuous supply of new individuals introduced by humans. Alternatively, even if invasive species become established, they may not spread widely due to limitations in their ability to disperse or due to environmental factors that filter out certain species. The findings highlight the need for environmental managers to focus on invasive species with known potential for invasion before they become widespread. This will require greater investment in early detection systems, such as environmental DNA surveillance, citizen science reporting apps, and improved monitoring of ballast water and water treatment programs.