18 March 2015

Wormy romance? Or feeding frenzy?

Thanks to sightings shared, it seems that recently, something is moving our marine worms in masses.
Bristleworm on the left, Fireworm (a kind of bristlworm) on the right.
Photo by Youna Lyons, 18 Mar 2015.
Are they in a mating frenzy? Or feeding frenziedly on dead fishes? So much more to learn and discover!



Youna Lyons, who has been tirelessly sharing daily sightings at Pasir Ris, shared today sightings of many worms. Some in bits, others longer and appearing complete. She said "about 5% were fireworms. Rest was purplish and pinkish with smaller red bristles. Every 20cm or so, in some places every 5cms."
Photo by Youna Lyons, 18 Mar 2015.
Gavin Chua also shared: "If you could check out Pasir Ris Sea at night, I'm sure you'll find something interesting ... coloured worms all of sizes adorn the shore."

Earlier, on 15 Mar at Kranji Reservoir Park, I saw a mass of worms at the water's edge. It appears that some of them were swimming, but not rapidly. Were they dead and moving in the waves?
Here's a video clip of the worms.
A closer look at the worms.
On 16 Mar, Thanks to Rene Ong who shared this: "I think you have witnessed the spawning of Nereidids (Family Nereididae). They are called epitoky at this stage. They will swim to the surface, release the eggs and sperms, and die.... So there's probably be millions of babies Nereidids swimming around now.... So no cause for concern."

More about this epitoky thing

Here's a fascinating post about Glowing Worm Sperm or Epitoky. I wonder if our worms glow when they mate too?

Are the wild fishes back?

Gavin Chua also shared: "Just a couple of days ago I was walking along the shoreline. We thought we could prove that theres still fishes around esp the hardy catfish, but we were proven dead wrong. Along the shoreline we counted at least hundreds of catfish skull pieces, each belonging to single fish, all almost perfectly white and with varying sizes from the size of your pinky to twice of that. And those were not the full skulls.. so at first i presumed that the smaller fishes esp baby catfishes would survive the epidemic but i was proven wrong upright. So, even though the dead fishes were cleared up, the skulls will always litter the beach as a grim reminder."
Photo by Gavin Chua, 18 Mar 2015.
Indeed, the decomposers are hard at work on the dead fishes. At Lim Chu Kang Jetty, dead fishes stranded on the high shore above the waterline are immediately consumed by maggots.
Here's a video clip of the frenzy of maggots (don't watch while eating or before eating!).

Other sightings

Sadly, Youna Lyons also reported palm oil wastes, some of them completely covering seagrass leaves.
Photo by Youna Lyons, 18 Mar 2015.
She saw much larger lumps earlier too.
Photo by Youna Lyons, 16 Mar 2015.
A weak spring tide is starting over the next few days. So hopefully, the tidal flushing will forestall another mass fish death.

But please do continue to share any interesting sightings that you have on our shores! Thank you to everyone who has shared!

No comments:

Post a Comment

LinkWithin

Related Posts with Thumbnails