Context:

• The increasing frequency of extreme weather events such as heatwaves, cold waves, droughts, and floods due to climate change is influencing ecosystems, said researchers at the Chinese Academy of Sciences in Beijing, China.

Key Findings:

• Extreme weather events affect land, marine, and freshwater ecosystems by influencing the displacement of native species with non-native.
• The scientists looked at 443 studies and analyzed 1,852 native and 187 non-native species residing in land, marine, and freshwater habitats and their responses to extreme weather events.
• Native Species Bear the Brunt of Extreme Weather: Native animals are more adversely affected by extreme weather events than non-native animals.
  • Heatwaves, cold waves, droughts, and floods disproportionately impact native species.
  • Native animals exhibit declines in body conditions, life history traits, abundance, distribution, and recovery.
  • For example The abundance of most native fish in the Rio Minho estuary, Portugal declined, but the abundance of non-native fish increased after extreme droughts and floods.
• Resilience of Non-Native Species: Non-native species are less abundant in terrestrial ecosystems but show less sensitivity to extreme weather events. Non-native animals often benefit from extreme weather events, outcompeting native species in the aftermath.
• Reasons for Resilience: Non-native animals have higher growth rates, higher phenotypic plasticity, stronger competitive abilities, quicker recovery and proliferation, and broader tolerance of disturbance compared to native species.
  • Non-native animals may be more tolerant of extreme environmental conditions, such as high salinity or temperature.
• Geographical Bias in Study:
  • The researchers advise caution due to biases, as most of the studies examined belonged to North America or Western Europe.
  • However, Understanding these dynamics is crucial for conservation efforts in a changing climate.

Source: Down to Earth

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