Ive seen different coloured yabbies?
Yabbies can vary considerably in overall colour and in the intensity of their shell colour patterns; some of this variation is due to age, but it is mostly camouflage to match the colour of their background. The shell and the female’s deep green eggs are coloured by pigments obtained by eating plants. Juvenile yabbies from muddy dams are normally very bland in appearance (the “white yabbie”); older yabbies are olive-greenish and more strongly marked. Darker, dirtier yabbies are ones that are not growing by making a new shell frequently; very clean, pale, often pinkish, juveniles have just cast off their old shell. Yabbies from clear, very clean waters tend to be bluish; those from green water, quite greenish; and those from tannin-coloured water, brownish.
