can fish think?

i think they are capable of making decisions. my pet goldfish - when i first have them - will disappear every time i approach the bowl. the moment they see my shadow or my shape, they will dash helter skelter and hide themselves among the pebbles. this reaction of theirs will be replayed over a few days. but, once they come to know that i do not pose a threat or a danger, they will stay their ground. in fact, in time, they will look forward to and eagerly await my presence.

when i went to feed the fish in the pond at bukit batok nature park this morning, the tiny ones would nibble at the bread crumbs. as babies, they are still blissfully unaware of the dangers in the real world. after a while, when everything seemed safe, the slightly bigger fish would make their presence felt. they would make loud splashes and snatch the crumbs in one gulp. but, the bigger ones would still stay away, playing a wait and see game.

this behaviour of the bigger fish may be explained in several ways. they are more experienced and therefore, they are more cautious. they do not act rashly; they study the situation carefully before embarking on the proper course of action. or they are more patient. or they are not as hungry as the little ones.

however, there is also this thing called herd instinct. i have also seen shoals of fish attacking, in a frenzied manner, the food that is thrown to them. these are fish that are used to being fed by humans on a regular basis. i witnessed this when i fed the kois at hausmann fish farm in lim chu kang.

incidentally, at hausmann fish farm, you can see a few giant fresh water fish in two huge tanks. one of the arapaimas is about 2.44 metres (8 feet) long.