Seagrasses disappearing at Terumbu Semakau?

This submerged reef off Pulau Semakau had lush seagrass meadows when I last visited it in June 2010.

When I visited again yesterday, I was shocked to see how little seagrass remained there. The Tape seagrass (Enhalus acoroides) were all short and cropped. I saw several small patches like this. There were a few patches with sparse but long blades, mostly in the Sargassum zone.

Terumbu Semakau is a submerged reef that lies just off the Semakau Landfill and some parts of the original Pulau Semakau.

Yesterday, I came across a small patch of Serrated ribbon seagrass (Cymodocea serrulata). I saw several patches of Spoon seagrass (Halophila ovalis). I didn't come across any Noodle seagrass (Syringodium isoetifolium) which we have seen here in the past.

The seagrass meadows were already sparse when we visited in March 2011. At that time, most of the Tape seagrass (Enhalus acoroides) were short and 'chopped'. But all the previously recorded species were seen: including the rare Noodle seagrass (Syringodium isoetifolium), Serrated ribbon seagrass (Cymodocea serrulata) and lots of Spoon seagrass (Halophila ovalis). .

Here's what the seagrass meadows looked like when we visited in June 2010.
And the lush growths seen on our first visit to Terumbu Semakau in May 2010.
Although Terumbu Semakau is not part of TeamSeagrass monitoring proper, a few of us who make regular trips to monitor our other shores do keep an eye on our seagrasses elsewhere. TeamSeagrass data on seagrass health on nearby Pulau Semakau and similar habitats like Cyrene Reef will hopefully help us better understand what is happening to seagrasses on all our shores.