Close Encounters with a Large Fish @ Semakau 07Feb2009

Close Encounters with a Large Fish @ Semakau 07Feb2009 from BeachBum on Vimeo.

Was alerted to this large fish (measured at 90cm by the Site 1 Seagrassers) caught in the shallows by the Team Seagrassers at Site 1 on Semakau. It must have been caught in the shallows because of a 200m long net stretching across most of the seagrass lagoon. It was gasping for air when I got to it. Careful about the sharp protusions just beyond the tail section, I used a plastic bag floating nearby to grab hold of the tail and lifted the fish cautiously. It was too weak to splash about and I lifted it clear of the water looking for a deeper pool. The low tide had drained the whole seagrass area of most of the water and I had to carry the fish towards the Sargassum boundary close to the edge of the reef. Once in the water again, it took about a minute to swim upright before heading in the right direction...out to sea.

What kind of fish was it? The info learnt from the Leaf Monkey Fishy Workshop pointed to the direction that this was a fast swimming fish due to it's V tail and narrow horizontal profile. Probably one of the 'Jacks'.

Short Clip on the long long net which prevented the fish from heading out to sea.

200m+ long net from BeachBum on Vimeo.

Short Clip on tiny juvenile fish which got stuck on the long net.

(if the small fish get caught too...then where are the bigger fish going to come from in future?)

tiny juvenile fish stuck in long net @ semakau 07Feb2009 from BeachBum on Vimeo.

Anemones & Kite Butterfly Fish @ Chek Jawa

Anemones & Kite Butterfly Fish @ Chek Jawa from BeachBum on Vimeo.

This is a large video so do wait for it to stream fully before viewing! or Join Vimeo in order to download the clip. Click on the Vimeo link for better quality viewing.

This seems to be the 'season' for kite butterfly fish (Parachaetodon ocellatus). A good many juveniles were spotted at Chek Jawa by quite a few people (including some over on the Changi side).

The clip shows kite butterfly fish taking shelter in close proximity to two kinds of anemones. The first shows a green carpet anemone whilst the second shows a peacock anemone (see http://www.wildsingapore.com/chekjawa/text/p510.htm for more on anemones.)
"Many sea anemones have tentacles armed with nematocysts, stingers that can inject toxins. They also have stingers that produce only a long adhesive threads (called spirocysts). These make the tentacles sticky and are used to capture hard-bodied prey such as crabs. Tentacles then move the meal to the central mouth, which can expand wide to swallow it whole."

Noting that contact with the anemones could be potentially fatal to the fish, it is a wonder why the fish would want to be so close to the anemones. The carpet anemone stings only at the top and so the area below it could provide refuge for small marine organisms. The only organisms which seem to have immunity are anemone shrimps and clownfish. It is probable that the KBF take refuge knowing that although the anemone could kill them, it would also keep away other predators like larger fish.

The peacock anemone can be seen to attach some of it's tentacles to the KBF. At one point, the fish seems to be struggling and it manages to pull away from the sticky tentacle. Perhaps the KBF do have a limited immunity to the stinging cells of the anemone?