04 June 2019

Special Changi shore still alive

We return to a narrow Changi shore and find it's still doing well. There were a lot of Pink warty sea cucumbers washed up on the water line on a large portion of the shore. I have no idea why this is so.
Pink warty sea cucumber (Cercodemas anceps)
This shore was hit by the Jan 2017 oil spill and scoured by loose stakes rolling on the shore. It's good to see that things are improving here.

Changi is echinoderm heaven. Today, for the first time on Changi, I noticed lots of Tiny red sea cucumbers. They are a small species and are not baby sea cucumbers. I saw much fewer Thorny sea cucumbers, a few Ball sea cucumbers. I saw two Sea Apple sea cucumbers, and one medium sized Garlic bread sea cucumber.
There were a lot of Biscuit sea stars from tiny to medium sized. And some small Cake sea stars which still had long arms, these arms become shorter as the sea star grows and makes it look more cake-like. I didn't see any Knobbly sea stars or Painted sand stars or Plain sand stars.
Biscuit sea star (Goniodiscaster scaber)
I saw many White sea urchins. Including this half dead one with spines still stuck onto some of its skeleton. These will fall off eventually, leaving the spherical skeleton. I didn't see any signs of Cake sand dollars today.
White salmacis urchin (Salmacis sphaeroides)
The Stone crab (left) and Maroon stone crab (right) are often mistaken for one another. It's easier to tell them apart when they are next to one another. The Stone crab has green eyes ringed with red, the Marine stone crab has all red eyes which are closer together.
Stone crab (Myomenippe hardwickii) and Maroon stone crab (Menippe rumphii)
I tend to see more weird slugs on Changi. Today, I saw one Volvatella slug, which is a sap-sucking slug which has an external shell!
Volvatella slug (Volvatella vigourouxi)
It was good to see some (but not a lot of) Fan clam shells and Gong gong snails. These animals tend to be heavily harvested on this very accessible shore. I didn't notice any signs of the clam take over that we saw in Feb 2019 at another part of Changi.
Fan shell clam (Family Pinnidae) and Gong gong (Strombus turturella)
I saw a large Burgundy anemone on the jetty legs! Is this the same as the small one I saw here during our last survey in Sep 2018? This is the first large one I've seen beyond Pasir Ris. I also came across one common Peachia anemones, but did not see any one Brown peachia, which was described from Singapore!  I saw one Swimming anemone and many Haddon's carpet anemone. I saw many Big hermit hitching anemones and some small Tiger anemones. On the jetty legs, there were lots of Lined bead anemones.
This shore remains soft and silty in some parts, perfect for sea pens. I saw many Sea pencils, some Slender sea pens and Flowery sea pens, and one Spiky sea pen. I also saw some cerianthids,
Many different colourful animals had settled on the jetty legs. Although I did see some Milliaris cowries and one Purple-spotted yellow flatworm, there were only a few small sea fans. Today, I didn't see any flowery soft corals or feather stars or Onyx cowries.
Near the jetty, there were lush growths of clean seagrasses. Mostly Spoon seagrass (with small and large leaf blades) and Needle seagrass (narrow leaf blades). I didn't see much Fern seagrass, During our last survey in Sep 2018, I noted that the shore in front of the seawall is rather barren and smells anoxic. Today it still doesn't have much seagrass, although there were some patches of Needle seagrass with very long narrow leaf blades.  I didn't notice any dugong feeding trails on this trip, although not much of the seagrass was exposed as the tide wasn't super low.
The tide turned even before the sun rose. Planes were landing in quick succession over us.
Changi beach with planes landing and seawall
The seawall replaced a series of long stakes and large bags that appeared to be some attempt at erosion control. During the Jan 2017 oil spill, the entire set up was badly covered in oil and remained so 12 months after the spill was cleaned up elsewhere.
Oil spill in the Johor Strait (5 Jan 2017) from Changi Carpark 4
Oil spill on this shore in Jan 2017.
In the past, many of the stakes have been uprooted from the high shore and littered all over the low shore. As the stakes move in the waves, they are probably also killing any seagrass or animals that attempt to settle there. A blog post by Jocelyne Sze on this setup in 2014 showed it was still okay. I observed it falling apart in Apr 2015, again in Aug 2016. This is what I saw on our last trip here in Dec 2017.
Dislodged stakes scouring seagrass meadows at Changi
Long stakes litter the shore in Dec 2017.
It's a relief to see the end to the stake situation. And I sense the shore is recovering.

More photos by Richard Kuah


Kelvin Yong