May 7, 2008

Pulau Sekudu: fish traps and other encounters

Another early start this morning, just four of us were off to check up on the marine debris situation at Pulau Sekudu. And how lovely to be greeted by some of the regulars on that shore: large carpet anemones and peacock anemones were everywhere.

During our last marine debris check in Dec 07 during a moderate low tide, we found lots of abandoned driftnets on the high shore, among the mangroves and rocks there. Today, is a very low tide and we were a very small team. So we decided to head out to the low water mark and the reef edge to look for fish traps.

It didn't take very long before we came across the first one.
Lots of crabs and fishes were trapped in it. The team gently release the fishes and then remove the trap.

As we went along, we also took note of the marine life on the shore.

This is the first time we are visiting Sekudu in the early morning in nearly 10 months. Our last morning visit was in Jul 07 with Dr Daphne to look for sea anemones. We also did an evening trip in Sep 07.

Compared to those trips, some of the sponges are now more plentiful, especially the purple long branching sponges, the bright blue and pink sponges typical of that shore. And the little wine coloured sea anemones have come back!
These little sea anemones disappeared after the flood of 2007 and we had a hard time finding them when we visited with Dr Daphne.

The carpet anemones generally looked happy and healthy, and were found in a wide range of sizes. We also saw some swimming anemones (Boloceroides mcmurrichii).

And these two anemones, that were hitching a ride on a living whelk!The two anemones together are bigger than their snail 'transport'!

As usual, on our shores, you have to look out for animals on animals. Like those animals found on the many clumps of flowery soft corals (Family Nephtheide) seen today.If you look closely you may find tiny little snails that resemble their soft coral hosts!As well as lots of tiny little brittle stars!Although brightly coloured, these brittlestars are hard to spot as they match their home perfectly!There was one little sea fan making a brave new start. A sea fan is a colony of tiny animals called polyps. The tiny white polyps retract when exposed leaving these tiny bumps in the central stalk.There was a little hermit crab clinging to the sea fan.

Since Chay Hoon wasn't with us, the only nudibranchs I saw were humungous ones.

Like this rather unexciting one that blends right with its surroundings. It has a white underside with brown blotches. It is possibly Discodoris lilacina.And a huge lumpy one that looks like a dull and uninteresting sponge!! It is probably Atagema spongiosa.But the monster find for me today was this ENORMOUS Luidia sea star (Luidia maculata)! It was bigger than my foot!Oh, that was kind of scary! The poor sea star, however, had lost one of its arms, so was left with only seven. Since it is so large, it's a good opportunity to take photos of the fine features of this star.This sea star has pointed tips to its tube feet, and the upperside of its body is marvellously textured. The star was very fast moving and quite aggressive looking. No doubt striking fear into the innards of little molluscs and other echinoderms that it eats.

There were also lots of Biscuit sea stars (Goniodiscaster scaber) and some Sand stars (Astropecten sp.) and the rest of the team saw one large Knobbly sea star (Protoreaster nodosus)! This is great! Knobblies used to be very common on Pulau Sekudu. Alas, I didn't see any.

As at our Changi visit yesterday, there were lots of White sea urchins (Salmacis sp.) as well as Pencil sea urchins (Prionocidaris sp.). We saw one Sandfish sea cucumber (Holothuria scabra) but no synaptids or other sea cucumbers. More about some of the trickier echi encounters.

There were lots of fishes in the lagoon and among the rubble.

The handsome Fan-bellied filefish (Monocanthus chinesis) is particularly plentiful.
I also finally saw a somewhat large Carpet eel-blenny (Congrogadus subducens) for the first time in a long long while.And a pair of bright blue fishes sheltering in the deeper water among the rubble. I have no idea what they are.

Sheltering in a pool near the lagoon was this very pregnant papa seahorse (Hippocampus sp.) and a small rabbitfish.Small rabbitfishes (Family Siganidae) were plentiful in the pools and sheltering among the rubble.

We didn't see any stingrays. Usually, there are lots of them in the lagoon.

Still MIA?

Unfortunately, we didn't come across any living corals. Strangely, none of us also encountered octopus today. But the shore exposed was large, and it was dark, and the team was small, so we might have missed those that were there.

Fish rescue

The tide rose with the sun. By which time, the team had found a total of 8 traps at the very low water mark. Some were abandoned, some were new. Many of the traps were about to be exposed as the tide was very low. Had the team not been there, the fishes would have died.

Each trap had about 10-15 large fishes including butterflyfishes, filefishes, groupers, puffer fishes. As well as many large crabs.Most of the fishes were still alive and swam away when released.

Although access to Pulau Sekudu is now restricted, drift nets are still laid just off the island (we could see the plastic floats holding up the nets).

We hope eventually fish traps and drift netting will stop being used on and near Chek Jawa and Pulau Sekudu.

Marine debris also continues to add unneccessary colour to the shores.
As we leave the island, the team bags the trash for disposal.
Despite the small team, it was quite a big pile of trash!Bravo to Andy, KC and Vyna for checking up on Pulau Sekudu!

Vyna shares thoughts about the causes and possible solutions to people laying drift nets and fish traps on her career breaker blog.

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