Thursday, September 6, 2007

Invertebrate mania at Semakau

Was at Semakau with a couple of NParks dudes to collect mysid shrimp (they're not shrimps, they just look like one).

After the early boat ride to our rubbish dump island, we got to know that we had to walk all the way from the jetty to the shore. I was so used to that comfy van ride from the TSG trips that the walk seemed endless (look at the picture below for a guage).

As usual, the vicious mozzies trailed us all the way from the forest till the seagrass meadow. Collecting mysid was kind of fun except for the fact that the tide is coming in fast and we need to work double time so that we can explore the place.

We found 2 sea cucumbers and Robin decided to become a surgeon and took out a piece of sharp razor to cut off pieces of skin off one of them for studies. Apparently this procedure does not hurt them and surprisingly it didn't even eviscerate.

I went out further to check out the cliff but the tide didn't allow me entry so I checked out the corals there instead. There were quite a lot of large polyped stony corals and their colours were amazing, most of them probably extremely fluorescent. They looked healthy too compared to my previous trip there where I found quite a few with parasitic flatworms.

There was also a mass mating of sea stars and we soon got engrossed in all the activity. Robin was trying to figure out why the sea stars stack atop of each other during mating and the rest of us were just getting high seeing all the procreation going on.

After we're done with the collection and the tide raging in like a flooding river, we quickly headed out and began on yet another long long walk to the jetty. Maybe the heat was getting into us but while most of us slept while waiting for the boat to arrive, Wilson and Uncle Tay decided to catch dragonflies instead.

Yeah we sure were dead beat after the long morning of work....

And its back to the lab to assess what we collected. We weren't sure whether the shrimp like creatures we got were mysid because it was hard to tell by looking but the microscopy work proved us right! Mysid have that characteristic "pouch" called the marsupium which would carry eggs. They also look a little different from shrimp when viewed from the top.

Another interesting find while collecting the mysid was this strange bright orange gastropod which appeared in mass. We've never seen it before, anyone knows what it is?

And lastly, this was being cultured by us, not collected from Semakau. This is a rotifer, strange looking creature isn't it?