I head out early this morning, with the full moon still silver in the lightening sky and mists shrouding the farming areas. There was a delicate sunrise over the shores when I met up with Jinwen.
What special finds await us this morning in this 'lost' and seldom visited shore?
This stretch of mangroves has humungous mud lobster mounds. And the mounds seemed to have grown even bigger than I remembered.
The seldom seen mudlobsters (Thalassina sp.) and their mounds play a critical role in the mangroves. As a mudlobster eats-and-digs through the mud, it recycles nutrients and allows air and oxygenated water to penetrate the otherwise oxygen-poor ground. All this digging eventually results in a distinctive volcano-shaped mound.
A mudlobster mound is drier than its surroundings so it makes a perfect home for other animals. Many animals can be found in living in these 'high-rise' mounds. 'Condo' dwellers include crabs, ants, spiders, worms, clams, snakes, and shrimps. I was too busy looking at plants today and didn't look much at the mounds. But in the past, we found the Hairy foot mangrove spider (Idioctis littoralis) which makes a burrow in the mounds.
Some plants also appear to grow better on these mounds. And today I saw something that looks like a Dungun (Heritiera sp.) growing on the mound. Also growing in profusion on the mounds were Jeruju (Acanthus sp.), Piai or Mangrove ferns (Acrostichum sp.) and various small trees.
The mudlobster condominium comes complete with swimming pool! Water is trapped in the mound system forming pools which shelter aquatic animals at low tide. In the pools today were all kinds of little fishes, too fast for me to shoot.And this large flatworm. I'm not really sure what kind of flatworm it is, but here's more about flatworms in general and mangrove flatworms in particular.
There are many large and tall trees in Lim Chu Kang mangroves. Few young trees can grow in the shade of these large trees.But when the big trees die, the sun streams in, and all kinds of young trees take root! In this area where several large trees appear to have died, I saw lots of young Rhizophora apiculata, Avicennia alba and Sonneratia alba. These young trees seem to be growing very vigorously, with fresh green leaves and sturdy branches.There was even this one Tumu (Bruguiera gymnorrhiza) that continued to grow even though the trunk seemed to have snapped off at one point, a little branch grew in a U-shape from the side at the break point!
Meanwhile, the old dead trees are rapidly being chewed up by all kinds of animals. The trunks of some of the dead trees, however, were still upright. I saw this pair of lively Belongkeng snails (Ellobium sp.) on a dead tree. I'm not really sure what is going on.In fact, the snails today seemed rather sociable. There was even this Mangrove murex (Chicoreus capucinus) taking a ride on a larger Belongkeng snail.And everywhere on tree trunks and even young mangrove saplings, the Lined nerites (Nerita articulata) in their pin-striped suits were massed in conference.Also active were the Chut chut snails (Cerithidea obtusa).And little Cat's ear mangrove helmet snails (Cassidula aurisfelis).
The mangrove trees provide hiding places and food for all kinds of animals. There were lots of spiders everywhere. The Golden orb web spiders (Nephila sp.) were particularly noticeable with their huge webs strung out between plants.
And I came across this spider hiding among the mangrove leaves. I'm not sure what it is.
One of the reasons why Lim Chu Kang mangroves are a bit of a challenge to visit, is the tremendous load of trash that ends up there.Besides the usual plastic and styrofoam,there are huge stacks of wood. Some of which appear to be driftwood that have been deliberately stacked.
There are abandoned fishing nets in masses here and there.And Jinwen and I came across this net that was draped on a tree. It doesn't look abandoned, but seems to be have left out for a while.
The trash adds to the challenges that young mangrove trees have to cope with.
This particular young tree was 'felled' by a piece of wood.
The Lim Chu Kang mangroves lies next to the Police Coast Guard Lim Chu Kang base (the big blue jetty in the background), and a makeshift but busy jetty.By the time we ended our field trip, lorries were lined up against the makeshift jetty. On the road, there was a lorry with an ice-machine busy producing ice by the bucket.People with trolleys were wheeling stuff up and down the jetty. It seems to be a point of seafood delivery.
Despite these, the mangroves there are rich. We saw lots of mangrove trees and plants, and the Hoya diversifolia climber which is listed as 'Critically Endangered'. I hope eventually the mangroves at Lim Chu Kang can eventually gain some sort of care.