Yabby (cherax destuctor)
also known as freshwater crayfish
What is a yabby?
Yabbies are a decapod (10 legged) crustacean like marron, rock lobsters and prawns. Crustacea belong to the very large group of jointed leg animals (arthropods) which includes insects, spiders and scorpions. These animals are peculiar in having their skeleton on the outside of their soft body, as a hard calcified shell or exoskeleton
Habitat
Yabbies inhabit dams, creeks, rivers, lakes ect. They are found all over australia and in some parts of New Zealand and PGN. They are principally vegetarians and are generally most active at night (nocturnal) where they spend their time foraging on the stream bed, eating water weeds and the decaying roots and leaves. Crayfish are, however, opportunistic omnivores, which means they can eat almost anything including meat.
Keeping yabbies
Yabbies can be caught at near creeks and dams but they are also sold at most pet shops. The only species sold at pet shops are the dam yabby, marron and the redclaw. The marron is a yabby like species but only inhabit western australia. The red claw is also a yabby like species but only inhabit queensland. the marron and redclaw are both relatives of the yabby as they are all freshwater crayfish. Keeping yabbies in an aquarium tank reqires sand or gravel about 3-5cm thick and lots of hidding spots. I use rocks as hidding spots in my tank but driftwood and also seashells make good hiding spots. Make sure you have a filter otherwise you will have to changed the tank atleast once a week. Yabbies are very territorial and wil fight to death with other yabbies if tank is too small so use a relativly big tank from 3-4 feet long with lots of places to hide
Moulting (shedding)
Crayfish like all arthropods shed or moult their outer skin in order to grow. This happens every three to four weeks in small crayfish (4-5 cm). The length of time between each moult increases as the yabbies get older to once a year in full grown yabbies. During the moulting phase the crayfish will stop eating and reduce activity, until on the day of the moult it will appear motionless. Crayfish are very soft and will hide until they have expanded into their new shell and the shell has hardened. It is advisable to leave the old shell in the tank as the crayfish will eat it as a source of calcium.
Feeding yabbies
Crayfish are principally vegetarian and will survive well on a diet of waterweed and almost any thinly cut vegetables such as pumpkin, potato, celery (including leaves), and apples and other fruits, chicken pellets and you can pick up crayfish food at petshops. You can also give them small amounts of meat or fish but it is not necessary. The important point to remember is not to overfeed crayfish. Crayfish only have a small stomach and will stop eating when full, leaving the remainder of the food. They do not need to be fed every day. A good feeding schedule would be one to two small pieces of food every two to three days. Remember to remove any left-over food after two hours.
Breeding yabbies
Yabbies will do the breeding alone but if yu are trying to breed them in an aqariu tank they will need lots of hidding places and fairly warm water if yu have a water heater this would be great set it from 20 - 25'C and once inpregnated as eggs start to appear try to give the yabbies about 3-4hours of sunlight a day. When eggs have hatched the baby yabbies or "fry" do not need any special food as they will feed on algae and also their mothers left overs. Once the baby yabbies have left their moters tail get as many of the babies away from the mother as possible possibly in a different tank otherwise the mother will end up eating them.
How to tell male from female
Males will have 2 tiny ball like objects attached to their last set of legs
Females have 2 indents on their thrd set of legs this is so the male will fit his genitals into the indents to fertilized the eggs
