Editor’s note: This image of the day includes the answer to the April 2022 puzzle.
A running hare. A jumping frog. A hungry dinosaur. Readers have suggested that the arrangement of islands pictured here resembles such land creatures. But in this part of the southern Philippines, it is the aquatic life that sustains many islanders.
Over 7,000 islands make up the Philippines. Of these, 10 main islands and hundreds of smaller islets are part of Tawi-Tawi, a province of the Sulu Archipelago in the far south of the country. Located more than 1,000 kilometers (600 miles) southwest of Manila, Tawi-Tawi is closer to Malaysia than many parts of the Philippines.
Most of the larger islands of Tawi-Tawi are visible in this image, including the island of the same name (also known as Tawitawi). Clouds frequently obscure the province from satellite views, so the natural color image above is a composite of cloudless pixels collected between 2013 and 2022. Images were acquired with the Operational Land Imager (OLI) on Landsat 8.
Note the large areas of shallow water (light blue) around many islands, especially along the coasts of Bellatan and nearby islands. It is the location of many seaweed farms. (There is another cluster of seaweed farms near Sitangkai Island, to the west of this image.) Tawi-Tawi Province is the country’s main seaweed producer, earning it the nickname “seaweed capital of the Philippines”.
Seaweed farming has been practiced in Tawi-Tawi for more than five decades. The practice originated in part because the waters here are generally clear and mostly protected from storms and waves, unlike the typhoon-battered northern parts of the country.
The main species of algae grown in Tawi-Tawi are collectively known as Eucheumatoids. If you’ve never heard of this type of red algae, you may have come across its extract, carrageenan, in food and beauty products. Carrageenan is widely used for its gelling and thickening properties, and it’s found in everything from ice cream to shampoo.
“In Tawi-Tawi, seaweed farming is not just seen as a source of income,” said Richard Dumilag, a marine biologist at Sorsogon State University who studies seaweed. It also plays a role in maintaining the bonds of families, often extended families, “living close to their source of life literally in the middle of the sea”.
Fishing, farming, logging and mining are other important livelihoods for the people of Tawi-Tawi. Notice the brown areas on the north side of Tawitawi Island and over much of Tumbagaan Island. These areas were stripped of vegetation and mined for their nickel ores.
Offshore, the reefs of Tawi-Tawi are home to an array of commercially important fish such as snapper, grouper and even rabbitfish. “Besides being the cradle of seaweed farming,” Dumilag said, “Tawi-Tawi is also considered the area with the richest diversity of fish in the heart of the Coral Triangle.”
NASA Earth Observatory image by Joshua Stevens, using US Geological Survey Landsat data. Story by Kathryn Hansen.