Daphnia Culturing

[stormhawk]

Is this spot along West Coast Road, where the river becomes a canal that finally empties into the Pandan Reservoir? I wonder if Pandan Reservoir itself might have these critters.

[tetrakid]

I agree with what Uncle Ronnie said. For what you know, there may indeed be different varieties of Daphnia in the waters. Besides the Pandan waterways, perhaps others like Sungei Tengah, etc. may contain some good finds, ideally enough 'big bad boons' to start some experimental cultures.

On second thoughts, a bag of live samples (with plenty of location water) might be interesting... who knows... maybe got different species of big bad boons amongst the tinier Moina!!!

[Draka]

Agreeing with what Uncle Ronnie said too! Now if only someone would organize a trip down then the shopping list of fishes everywhere will be finally fulfilled...

Anyway Ron, there weren't any actual scholarly articles on the phenomenon, or rather if you want there were plenty of papers on the 1998 global coral bleaching event (but not much on our local). As we all know, Daphnia, as with many planktonic crustacea, are unable to survive at high temperatures, if the temperatures are raised too high too quickly. In such situations, they might not even be able to leave ephippia.

The reason I said the sudden sharp decrease in populations of Daphnia could possibly be linked to the 1998 global coral bleaching event is because this was the first time in our island's recorded history that the heatwave was strong enough and temperatures high enough to bleach our corals. This would mean that our freshwater bodies and their inhabitants would be affected as well, including Daphnia.

Here's a link to the university coral page, the reference to the 1998 coral bleaching event is at the bottom: http://coralreef.nus.edu.sg/

[tetrakid]

It's true that the warming effect is real. It's a pity though that the Daphnia do not take the chance to evolve themselves into an tougher breed of even bigger 'mean big bad boons' able to withstand tougher climatic conditions, but let the tiny bitsy Moina cope better, lol.

[Trichopsis]

Possibly because the tiny Moina can shed excess heat more easily than the larger Daphnia? Just wondering.

[RonWill]

or perhaps Daphnia sp. simply isn't indigenous.

[tetrakid]

How nice if the fish get to savour air-flown imported cuisine of succulent Red Russian Magna once in a while.

or perhaps Daphnia sp. simply isn't indigenous.

[jf1216]

Is this spot along West Coast Road, where the river becomes a canal that finally empties into the Pandan Reservoir? I wonder if Pandan Reservoir itself might have these critters.

that area i did not venture til there coz the winds are strong there thus making it harder to see them swimming around.
i usually go to the canal that is connected to the IMM one and clementi the V-corner....
let me see if i can upload the map here.
timing to go is in the morning 7~10 or evening 6~7pm where the wind condition is less strong.

[jf1216]

i believe that drain leading to the pond along lim chu kang chicken farm should have the red boon. when i was young, i was being bought along before to culture them..including tubifex worm will get stinky after each time lol

[jf1216]

here the map if u guys interested in getting them

untitled.JPG

the location is marked on 1 and 2 with the yelllow color strench i do with yellow spray

[Draka]

Omg thanks a lot jf. I was under the misconception they were nearer to the reservoir...

[stormhawk]

Thanks for the map jf. It's very near to where my gf lives, just across the AYE. I remember this section where the two drains meet. Never expected to see Moina there.

At the part of the canal that goes below West Coast Road bridge, there's occasionally one or two carcasses of the "eat %^$t fish" aka common pleco that might be hanging from the railings, so it won't be a surprise if the Moina are there too. They have some booms in place that control the flow of the water into the main canal downstream.

[Draka]

Nope stormhawk, can ascertain they weren't there. At least not on midnight recently even with a strong torch shining around.

[RonWill]

Moina are usually found very near the surface during the day, presumably due to warmer water that is lower in oxygen level. Comes dusk, like the rest of non-nocturnal creatures, they go to rest.

[stormhawk]

Based on jf's map, there is a small drain not shown on the map that leads to the left fork of the river. Perhaps that small drain near the IBP may have them too. It's overrun with vegetation.

[Trichopsis]

Seems like aquarists have a very high likelihood of reverting to "kampung boy" mode, hopping into drains and canals in search of fishes and inverts.

Getting back on topic, according to my copy of A Guide to Freshwater Life in Singapore, Moina is mentioned and pictured, with a photograph of another form labelled as Alona. The latter looks quite different from Moina and Daphnia.

Attachment 29263
Alona affinis from Cladocera.de website.

Private Lives: An Exposé Of Singapore's Freshwaters has photos of 2 different water flea species, but doesn't name them. However, my guess is that they represent Moina and Alona as well.

It also says that water fleas can be migratory, moving up and down the water column daily. Species found living in the shallows in the day may migrate to open water at night. So whether or not you can find water fleas may really depend on the timing.

[stormhawk]

The Moina are attracted to light though, which is why they suffocate easily in a small container with a light source at one end. They congregate at the end that has light and end up asphyxiating each other.

[tetrakid]

This explains why often after a boom comes a crash. Even with subsequent harvesting, it may be too late, as by then the downward spiral has already kicked in.

The Moina are attracted to light though, which is why they suffocate easily in a small container with a light source at one end. They congregate at the end that has light and end up asphyxiating each other.

[jf1216]

happy daphniaing all....
maybe u guys want me to organise a trip there on one of a weekdays?
weekend my time belongs to my wife lol...
nearest place to park is along those faber roads and provide there is no man in white summoning our vehicles lol...

[stormhawk]

It's not the boom, it's the Moina's habit of being attracted to light. Other Cladocerans may or may not have such an affinity for light, but Moina are attracted to a focused light source like those flying ants we get every now and then.