St John's Island still alive

Just minutes from the Central Business District, lies one of Singapore's last natural cliffs at St John's Island. The rocky shore and reef edge has corals. There are also seagrasses throughout, as well as rare mangrove trees on the untouched western shore, which is part of the Sisters Islands Marine Park.

A large team checks out the shores well before dawn. The corals seemed fine, seagrasses still doing well. As usual, the team make all the special finds. I will update later.

I have never seen a lot of corals on this shore since I started surveying it. Most are boulder shaped, with common plate corals, mostly small to medium sized, but also a few very large colonies. Today, I saw the usual assortment and all seemed fine. I didn't see any bleaching corals, or corals with dying portions. As in the past, I saw a variety of small to medium-sized colonies of leathery soft corals.

St John's Island has one of the few remaining natural coastal forest, growing on natural cliffs leading onto a natural rocky shore with corals and other marine life.

The real treasures are the grandmother Nyireh laut tree and her daughters that grow on the western shore of St John's Island, which overlooks the Sisters and is part of the Sisters' Islands Marine Park. Nyireh laut is Critically Endangered in Singapore and we probably have only about 7 trees on our shores. There are another 3 on Sentosa Tg Rimau. Today, they are still fine, although the large wooden pallet is still lodged near one of the daughter trees. 

It is natural for landslides to occur on our natural cliffs. Although these take out trees that grow there, these also produce the wonderful boulders and pebbly shores that we find so pleasing. Today, we revisit the landslide on the western shore, with the fallen tree at the base, mostly dead, though the upper parts remain green. The bare rock is slowly being colonised by small plants. On the eastern shore, the smaller landslide is still visible. While a very old landslide that had been cemented over is now almost hidden by foliage.

The sandy artificial lagoons are alive! Dotted with burrows of Sand bubbler crabs, signs of Acorn worms and on the high shore, Ghost crab burrows. There were still some Common sea stars and I saw a Common cerianthid.

Similar to our survey in Oct 2025, seagrasses here seem fine! Outside the seawall of the swimming lagoons, I saw clumps of Tape seagrass with long leaves (30-50cm), though many were cropped shorter (about 20cm). St John's Island is one of the few shores left that still has some long Tape seagrass. Inside the swimming lagoons, and on sandy patches in the natural rocky shore, there are large patches of Spoon seagrass with small leaves with sprinkles of Needle seagrass. On the Western shore facing Sisters Islands, there are still sprinkles of Sickle seagrass among the rocky areas. All seagrasses looked fresh and green and healthy.

There seems be a bloom of Bryopsis green seaweed on the small area of the rocky reef edge on the northern tip of the island. The annual Sargassum seaweed bloom is just starting up. Today on St John's Island, the seaweed getting fluffy at the reef edge near the jetty. But are starting to form thick carpets with long strands on the western shore facing the Sisters Islands. I'm tracking the bloom season as we feel that in recent years, it is starting earlier and ending later.

St John's Island in the Singapore Blue Plan

The Singapore Blue Plan 2018 highlights the importance of St John's Island to our marine biodiversity. The cluster of Kusu, Lazarus and St. John's Islands has been recommended by the Singapore Blue Plan 2018 for elevated protection status.

The Sisters Islands from the western shore of St. John's Island.

The Blue Plan highlights that Lazarus, St. John’s, and Kusu Islands are established sites for coral nurseries as their shoreline offers ideal sheltered areas for growth of corals. Designating these islands as No-fishing Areas can bolster their rehabilitation. Protecting a larger cluster of islands means zonation plans for use can be implemented to manage tourism and human impacts.

DOWNLOAD the Plan, SUPPORT the Plan! More on the Singapore Blue Plan 2018 site.