Key Facts
- Location
- Bijagós Archipelago, Guinea-Bissau
- Number of islands and islets
- 88
- Image date
- Nov. 28, 2025
- Tidal frequency
- Twice each day
- Image credit
- NASA/Lauren Dauphin, USGS
- Text credit
- Adam Voiland
Background
The Bijagós Archipelago, known in Portuguese as Arquipélago dos Bijagós, is a group of 88 islands and islets off the coast of Guinea-Bissau. The islands are flanked by a maze of sandy channels, mudflats, and mangrove forests.
Twice each day, tides ebb and flow through this intricate coastal landscape. The regular rise and fall of the sea is a defining feature of the region, shaping both its geography and its ecosystems.
Current Situation
A satellite image captured on Nov. 28, 2025, and released by NASA, shows the dramatic effect of these tides. Around low tide, intertidal mudflats and sandflats emerge from the sea, causing the islands to grow significantly in size.
Hours later, as the tide rises, the exposed flats are submerged again, and the islands shrink back. The image, taken from above, highlights the stark changes to the landscape that occur twice daily.
The image credit is given to NASA/Lauren Dauphin and USGS, with text credit to Adam Voiland.
| Feature | Detail |
|---|---|
| Islands and islets | 88 |
| Tidal frequency | Twice each day |
| Image date | Nov. 28, 2025 |
Impacts
The tidal process has a direct impact on the archipelago's wildlife and ecosystems. The mudflats and sandflats that emerge at low tide provide feeding grounds for birds and other marine life, while the mangrove forests rely on the regular tidal flow.
The changing landscape also affects navigation and human activities in the region, as channels and shallow areas appear and disappear with the tides. However, the source does not specify the exact consequences for local communities.
The image serves as a visual reminder of the dynamic nature of coastal environments and the powerful forces that shape them.
Future Outlook
Scenario analysis: The possibilities below are not certain predictions.
If tidal patterns remain consistent, the twice-daily emergence of mudflats and sandflats will continue to reshape the islands' outlines, maintaining the archipelago's distinctive character.
Should sea levels rise or tidal dynamics change, the balance between submerged and exposed land could shift, potentially altering habitats and the visibility of the islands from above.
Future satellite observations may provide further insight into how these tidal waters continue to influence the region, but no specific predictions are available in the source.
Source: NASA
