Extended Data Table 2.

Overview of estuaries with tidal barriers

The table lists the name, approximate distance from the estuary mouth, year of construction (where applicable), and whether the barrier is natural or anthropogenic. Tidal barriers, defined as inland structures or natural features that restrict tidal propagation, are present in 13 of the 25 estuaries studied. Anthropogenic barriers include weirs, dams, and surge barriers, while natural barriers consist of geological features such as falls.