Tuesday 21 November 2017

How Big Are You? - J




Dear J,

I am about half a metre long, but I may still have a bit of growing to do .

My uncle is about 65cms long!

Hello Fishy, What Do You Eat? - Minu

Dear Minu,

I eat smaller fish in our billabong.

I am a carnivore but my little brothers and sisters and I could also be eaten by the bigger fish like Mandageria fairfaxii.

That fish is really the top predator in our billabong

Tuesday 14 November 2017

Do Fish See Things In Colour? - J

Dear J,

Fish eyes are generally similar in structure to the eyes of other vertebrates. Many species of fish have colour vision and some can even see ultraviolet which I'll bet you can't. You must remember that water absorbs lighht so it gets dimmer and darker the deeper you go. Shorter wavelengths of light (colours like blue & violet) penetrate deeper in the water than the longer wavelengths (red, orange)
(red, orange)


Hello Fish! Is it Cold in the Water - Minus

Dear Minus

When our billabong was full the temperature of the water didn't vary much except in the very top layers. Sadly the water level in the billabong has been getting less and less. This means it warms a bit more in summer than it used to. The biggest problem for we fish is that the warmer water holds less oxygen so a lot of my companions in the pond have slowed down a lot and have breathing problems. (makes it easier for my family to catch dinner)

Fortunately for my family we can breath air for a while, if we stick our nostrils out of the water