Yabbies come in all different colours. As a rule they will generally colour up to the colour most suitable for camouflage in the environment in which they live. Yabbies can be white or black, blue or green or any combination in-between. Most farmers grow a genetically blue yabby so most offspring will have some blue in them, the intensity of that blue will depend on the culture conditions. For example:
Muddy milky coloured water tends towards light brown bodies and light blue claws.
Red clay, muddy dams tend towards bright blues and pinks.
Clear shallow water tends towards blue yabbies.
Clear deep water tends towards dark blue yabbies.
Dams in forests with tannin and surrounded by trees tend towards green and black etc.
Backyard Aquaponics
