Leaf-Porter Crabs

6 03 2008

Here is a short write up about these unique species of crabs, Leaf-porter crabs, scientific name, Neodorippe Callida.

The Leaf-porter crab, as the name suggests, carries a leaf (or any other light, floating debris) on its back! Its last 2 legs are modified to carry objects, and has sharp hooks on its legs to gripe floating leaves. (the one we saw was carrying a piece of plastic!)

They are generally scavengers, and due to their carrying a leaf on their back, are master camouflagers! They usually appear at dusk and are attracted to fishing lights and do not usually grow to a very large size.

We sure hope we’ll see more of these wonderful crabs!(:

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ζ··ζ°΄ζ‘Έι±Ό (Fish in troubled waters)

24 02 2008

Today, 4 days after we used syringes to poke holes in Thalassia hemprichii, we went back to collect the samples.

Sihui, Siling and I arrived early about 3.40pm when the tide was still very high. We thus proceeded to settle down at a bench and take a nap, while waiting for Mr Lim to come at 5pm.

However, even at 6pm, the tide was still very high, so we wandered about the higher parts of the beach (nearer the fence), and saw quite a few interesting organisms!

There were many of these sea slugs (Onchidium) on the sea wall, and Mr Lim is simply fascinated at how fast they can glide/slide/crawl over the rocks.

Fiddler crab!

Another crab whose ID we’re not sure of…
[edit: according to revetaw, this is probably a sesarmine crab. thanks loads to revetaw for telling us :D]

Si Ling also managed to spot a snapping shrimp (also known as pistol shrimp or alpheid shrimp),which was out of its hole for some reason or another, and got caught by us!

Mr Lim is infinitely jealous of us, as he spent much of his time trying to coax a shrimp out of its hole on thursday (but failed), while we managed to catch it in a minute! Snapping shrimps are fascinating creatures, they use their one oversized claw to stun their prey!

Meanwhile, Si Hui was looking at this pair of hermit crabs…

She was observing it for quite a while, and said they look gross…

We also saw this weird looking thing that we couldn’t identify… Can anyone help please? (:

And it seems like Labrador Park is quite a popular spot for photoshoots!

xD

Finally, at about 7pm, the tide was low enough for us to identify our plot and we immediately started cutting the Thalassia. As the tide was about our ankle level, and there was still heaps and mountains of Bryopsis floating around, it was really difficult to search and find the sheath for cutting, and Si Hui and I were forced to feel around with our fingers (thus the name, which literally means groping about [for fish] in murky waters). Slowly, as the tide receded, we were able to see the bare patch on the ground with random bits of Thalassia left.

The two bricks marked out our plot.

Then, when we were about to leave as the sky got darker, Si Hui and I spotted this blue thing floating in the water. Thinking it was a piece of rubbish, I picked it up, intending to throw it away. To my surprise, there was a crab underneath!

The Leaf-Porter Crab (Neodorippe callida)! It thought that the piece of plastic floating around was a leaf, and so hid under it.

That rounded up our day, and we went home happily (having spent nearly 4 hours at Labrador Park!) πŸ˜€

Although this may be our last time coming down to officially conduct research, we sure hope to be able to make frequent visits down to our favourite park!(:





Beach combing!

22 02 2008

We went down to Labrador Park again today, purely to explore the low tide, with no intentions to do any work!

Walking towards the beach, we saw many Sun Skinks(Mabuya mutlifasciata)! They were sun bathing peacefully, until Mr Lim came along to disturb them xP

As the tide was still high when we arrived, we walked along the jetty bridge to a little pavilion where there wasn’t any ants to wait.

While we were on the bridge, we noticed that the side of the beach with the gate had more algae than the other side. Mr Lim said it was because the other side was more rocky…

We also saw this adorable little fish, which Mr Lim says is known as the “Gar Fish” [many thanks to SJ for pointing out the spelling mistake :D] and belongs to the pipefish family! Here’s a photo of it, although you can’t really see it.

It was refreshing to look at Labrador Park from a different perspective, and the wind was also very enjoyable(: thus we took out biscuits and drinks and started a little picnic!

After the tide receded, we went down to explore the rocky shore! We didn’t see many organisms at first, maybe due to the high turbidity or just that we were too noisy πŸ˜›

Here are some pictures of the organisms we saw:

Unidentified Anemone! (Mr Lim was poking it and bully the poor thing!)

I’m not too sure what this is as well..

baby Juvenile Crab (not sure about its scientific name)
[edit: from what revetaw says, its probably a leptodius πŸ˜€ thanks loads for telling us revetaw!]

Mr Lim found this cute teddy bear crab, aka Hairy Crab! (Pilumnus vespertilio)

A baby Hairy Crab! Also found by Mr Lim while he was enticing a snapping shrimp to come out with a strand of brown algae (Sargassum)

We also spotted this Red Egg Crab which was wedged in a crevice and refused to come out, and a couple who was taking wedding photographs along the beach

Thus concludes part 2 of our 3 part Labrador Park spree where we go down to Lab Park every 2 days πŸ˜€ We will be going down again on Saturday to collect our Thalassia growth samples!(:

Special thanks goes out specially to Mr Lim, who brought us down to Lab Park despite the fact that his eye was hurting and he should have been resting at home! Thank you, we really appreciate it πŸ˜€





Lab Park again!

21 02 2008

We left for Labrador Park on Tuesday during school, and reached there while the tide was still quite high.

The first thing we noticed when we reached was that the whole beach was covered in the green algae (Bryopsis).

We heard from Mr Lim and later, Ms Yang Shu Fen and Ms Siti, that these were seasonal though, so we weren’t particularly worried, although it did make the whole shore look dirty, unwelcoming and the water really turbid.

We also noticed that the construction works has been completed, as the barrier has been taken down. Another thing that our group is interested in is how the construction works could have affected the water quality at Labrador Park, so perhaps after the next group takes over us, they would notice a new trend!

As the tide was still quite high and Ms Siti and Ms Shu Fen hadn’t arrived, we started exploring the shore. We saw a small Moon crab

and some Fiddler crabs, as well as a little catfish.

Once the tide was reasonably low, the 6 of us (Si Hui, Si Ling, Mr Lim, Ms Siti, Ms Shu Fen and I) started our monitoring. Due to the excess Bryopsis floating about all over the place, it was really difficult for us to estimate the percentage cover of seagrasses. (Almost everything was covered under seaweed!) However, we still managed to complete our 33 random quadrats, and Ms Shu Fen and Ms Siti even spotted the Thalassia flower, which we heard was really rare!

It was also the flowering season for Enhalus, and Mr Lim spotted their flowers, although it hadn’t bloomed yet.

The Enhalus is the only species of seagrasses whose flowers have to be fertilised out of water; all other seagrasses complete their entire life cycle under water. “Seagrasses are so cool yeah!”

After monitoring, we punched holes in a little plot of Thalassia. This time, as we neglected to bring raffia and tent pegs, we improvised with chopsticks and bricks! With everyone except Mr Lim helping, the job was soon done, and as we left for the shore, we saw this huge catfish!

It was stranded by the receding tide and was hiding, when we ungraciously intruded into its presence and started snapping shots of it. It probably felt like a celebrity xP

We also saw markings in the sand which Ms Siti says looks like those made by Brittle Stars, although we didn’t see any 😦

Thus concludes our group’s last monitoring session at Labrador Park 😦 We will still continue coming down whenever we are free though, we are too attached to Lab Park! We will be going down again today during our RS block, just to look see and as Mr Lim says, picnic! (:

Special thanks to Ms Siti and Ms Shu Fen for coming down to help us!





mudskippers!

17 11 2007

hello, this is sihui and i’m here with the research on MUDSKIPPERS

MUDSKIPPERS

here’s a photo of a mudskipper we saw that day with the teachers

Mudskippers leap extremely quickly. We saw them at labrador that day when doing beach combing with the teachers, leaping around on floating pieces of driftwood, “stoning” for a few seconds, then leaping back into the water. They’re not the prettiest things, but they’re clever. And they look slick and slippery, judging from their “wet look”.

MUSKIPPERS 2!!

photo no. 2 of mudskipper seen that day!

Unlike hairy crabs and flower crabs, mudskippers do not refer to just one species but rather a number of species of fishes that are related to each other, in the subfamily Oxudercinae. They are generally known for their excellent amphibious abilities and they are mainly found in the Indo-Malayan region. They are rather common, I suppose, but they are difficult to spot as they have an unobtrusive brown colour that seems to camouflage them. you can’t really spot them until they move, quick little darting leaps that they take drawing attention to them.

Unbelievably, mudskippers are, as mentioned before, still FISH! However, they are not ordinary fish! They can “preserve” air bubbles in their gills to keep with them as they go on land, which is what allows them to survive on land for longer periods of time as compared to other completely aquatic fishes.

Some particular species even have cooler adaptations to allow them to last longer out of water. Some species (e.g. Periophthalmodon schlosseri which some laymen call the “giant mudskipper” ) slow down and accelerate their heartbeats when in water and out of water respectively. Also, some species of mudskipper even have the ability to reduce the rate of oxygen consumption rate in water, to the extent that even in hypoxic conditions (where oxygen levels are very, very, very, very low) they can still survive and only produce their lactic acid (a byproduct of anaerobic respiration aka respiration without oxygen to produce energy) after several hours.

And apparently, some species have such amazing abilities to last on land for so long, scientists are considering whether they can be analysed and compared to that to land animals, so that their amphibious nature can be developed in animals such as humans as well!

For more cool information on mudskippers, you can refer to www.themudskipper.org! it’s rather profound though so it might need some time to digest.

*Did you know that NUS has a magazine publication called The Mudskipper? It’s editor is none other than Dr Sivasothi, the person who coined us with the name “Seagrass Angels”

[edit] hello people, sorry for the mistake, according to Dr Sivasothi,Β the editor of The Mudskipper changes annually! sorry! [/edit]





Flower crab!

10 11 2007

As jocelyne posted earlier, Mr Lim set us homework – to research on one of the creatures we saw that day we didn’t do monitoring. Mine was the flower crab. (Portunus pelagicus) [See, it even has alliteration, how nice!]

Anyway, the flower crab is also known by a variety of names, such as the blue swimmer crab, likely because the adult male crabs have blue markings on their shells and long pincers. Females, though, are dull green or brown. It’s known as the flower crab in East Asia, while in Australia, it goes by other names.

Flower crabs have a hard upper shell (carapace) which can be rough or covered with small grains. They also have pincers that elongate with conical teeth at the base of their “fingers”. Their legs are usually laterally flattened at varying degrees, with the last two segments of the last pair paddle like. Probably so they can paddle. haha.

Unlike the very docile and adorable hairy crab, the flower crab (or at least the one we saw) is vicious and not afraid to pinch people… It escapes really fast, too. Being highly aquatic, they cannot stay out of water for very long. It generally survives in a habitat with sandy mud or sand substrate.

The flower crab preys on small fish and other small animals, while people prey on it after steaming for their nice, delicious seafood dinners.

According to A Guide to Seashore Life in Singapore, because flower crabs are crustaceans, they frequently replace their shells after growing too big for the older ones. (just like how people change clothes when they grow fatter ;D ) These moults (shells without crabs) are then left on the shores. They are very easy to differentiate from real crabs as they are light, do not have flesh in the inner layers, and have transparent eyes. O_____O They also don’t stink.

The flower crab takes about one year to mature.

The flower crabs we see at Labrador are really tiny but fierce, though, so I doubt anyone would eat them. Perhaps they’re toxic too, like the hairy crab! That will teach people to steal crabs from labrador..Β  (cue evil laughter)

*will post a picture here, after we get it*





Hairy crab!

2 11 2007

Since we did not conduct monitoring on Saturday, Mr Lim set us some homework! Each of us had to go home and research on a particular creature we saw that day.

As the title suggests, I’m doing hairy crabs (Pilumnus vespertilio)! From what I’ve read in various websites, hairy crabs are common in Labrador Park and rather a favourite, as they’re really adorable and docile.

It has hairs covering its body, giving it a very furry look, much like a cuddly teddy bear! It will also sit nicely on your hand and not scuttle all around like other crabs, thus I always get very excited when i find one! xP

If you’ve read The Sunday Times on 28/10/07, you’ll see that in the Life section, there was a recipe on hairy crabs. It appears that the Shang Hai counterparts are considered a delicacy in many places, and it is best eaten steamed. I was rather put out at the fact that such a cute little creature would be eaten. And there was even a section teaching readers how to eat hairy crabs without getting very messy. The details were rather vivid, I could imagine the poor hairy crab being eaten very clearly 😦

Nevertheless, from what I’ve read on habitat news, those in Labrador Park cannot be eaten because these crabs “may eat toxic zoanthids (colonial anemones) which can make this crab mildly poisonous.”

-still waiting for a picture…-