Human Alteration and Disappearance
A new study has revealed that nearly half of the world's estuaries have been significantly altered by human activity, with a staggering 20% disappearing over the past 35 years, particularly in Asian nations.
Estuaries, where rivers meet the sea, are often referred to as "nurseries of the ocean," providing critical breeding grounds for fish and habitats for diverse bird species. The surrounding salt marshes also stabilize coastlines and mitigate flooding.
Global Estuary Losses
Using satellite data, researchers quantified changes across 2,396 estuaries from 1984 to 2019.
The results, published in the journal Earth's Future, indicate that more than 100,000 hectares of estuaries have been converted to urban or agricultural land over the 35-year period, with the vast majority of losses (90%) occurring in developing countries in Asia.
Developed Nations: Intervention and Restoration
In contrast, estuary losses have been minimal in high-income nations over the past 35 years, primarily because extensive estuary modification occurred decades earlier during these nations' rapid development phases.
Recognizing the ecological damage, several high-income countries are taking steps to remediate these losses. For instance, the United Kingdom has invested in the Tees Estuary, restoring it to a thriving mudflat and salt marsh habitat that reduces flooding risks, enhances climate resilience, and replenishes fish populations, bringing nature back to life.