Backyard Aquaponics
A place to discuss aquaponics

Now I know that I would have to go work in the shed if I wanted to make that sorta food - kinda stinks the whole hou se out for ages - the wife would carstrate me herself!:shock:

Hey Y'All....

I'm a newbie and haven't posted yet, but I thought I'd weigh in on this subject. I've been raising RedClaw for a couple of years and plan to try wintering them over in a greenhouse in an aquaponics system next.

RedClaws are well adapted to living in crowded confined quarters because there rivers naturally dry up annually. They manage to survive this period before the rains come again practically piled upon each other without eating each other. This makes them ideal for aquaculture because they can be stocked very densely without much fighting.

These little compartments are seen often but everyone I've ever talked to that has tried it has given up because feeding is so labor intensive. RedClaws will stay in a small territory where they feel safe if food falls right in front of them, so I'm not sure how miserable they are in this unnatural environment.

I am experiementing with various stocking densities from 1 per gallon to 3 per gallon and haven't found much difference in aggression or growth rate. The only issue seems to be plenty of places to hide and water quality in heavily stocked tanks.

RedClaws don't deserve their reputation for cannabilism. I find that as long as they have safe places to hide out when they recover from a moult, they all are fine. In my spawning tanks, males sometimes fight to the death if they are unmatched in size. The hatchlings do thin the ranks if crowded for the first 3 months of life, but I think this is directly related to stocking density and the number of hides as well. I also find keeping an adult in their tank keeps order....the larger of the juveniles don't get out of control because Mom or Dad is keeping order. I've never seen an adult eat a baby....and have had mixed sizes and ages all living happily together.

I'm in agreement that raising livestock in an environment that is reasonably natural is much more appealing. I think "happy" crayfish taste better !!

CC,

Thanks for the great info.

Do you find that they try to get out of there tank much.

THe one I got this past week has tried, so I have weighted the glass down to keep it confined!

Another thing that i have found, is that they will try to escape much more when the water conditions are not to their liking (something fish don't have the luxury of doing )

They REALLY don't like ph less than 7.0 and would prefer it between 7.6 and 8.4 from memory. I try to keep my systems between 7.0 and 7.5 to keep everything sorta happy.

Redclaws spend a lot of time plotting their escape, so covers on their tanks are a must!! They seem most in danger of escaping right after they've been moved to a new tank or if the water conditions aren't to their liking.

I was interested to see what was happening with yabbie culture and see what alternatives to extensive culture exist. The extreme yabbie culture certainly looks like a way of ramping up productivity but does make me feel a little uncomfortable about the method. I was surprised to see a discussion about scientific method in this forum, however I don't think it is entirely inappropriate to consider ethical aspects of what we do with the animals we farm/companion.
However from a practical and quantitative science evidence point of view two things might be good to consider here with animal culture for food production:
1. If you increase animal density you increase the risk of disease and massively increase the the opportunity for disease transmission. For an extreme example, have a look at some of the historic information on intensive prawn farming in Asia (Taiwan
for eg). Not sure how the water flows through the system in question but I assume it is recirculation so animal density is likely an issue for disease transmission.
2. Some interesting information has more recently been published on chicken nutrition and the benefit to chickens cultured on grazing natural pastures as compared to those raised intensively on least cost diets. The bottom line being health benefits for the chickens and the consumer.

Regardless of arguments about animal ethics when culturing animals for human consumption in my book the golden rule of animal culture "you are what you eat"

great discussion - surprising content

Wow, first post and you're reviving a discussion from 7 years ago, you must have used the search button....

In my opinion, earthen ponds are and always will be the best way to farm yabbies.

Did not really pay much attention to how old the post was - still a hot debate over culture conditions for lots of food animals - wonder if there is any current information on these intensive systems for yabbies?
Have just started to look and this site and info caught my eye.
Cheers

What about dams filled with those things too?
might need some filtration then i suppose.


:wacko:

EDU's never took off. As far as my knowledge goes and what Ive read is there hasnt been a successful or even remotely viable operational EDU system ever... well not in aus anyways. Its the sickest form of cage farming ever created and it dazzles me that things like these even perk interest. Its just plain wrong and not remotely viable anyways.

Yabbie farming has been around for decades and there are a number of high profile marine biologists that have worked with the cherax strain for a very long time to intensify and push the industry forward using modern science. Many years ago I read some really good articles by an australian marine biologist Dr Craig Lawrence who bred a Cherax albidus with a Cherax rotundus which produced only male offspring, which quite possibly might become the future of aussie yabbie farming one day. An all male populated earthen pond with managed stocking controls will produce the largest and fastest growing yabbie.

In australia, the yabbie farming industry is huge.... and growing. Not one successful operation that I know of would look twice at a creation like those. EDU systems are bull shit money spinnning idea created by uneducated no bodies.

I just found this from...

http://www.fish.wa.gov.au/Documents/aqu ... bies.pdf...

"Separating males and females by hand is time-consuming and prone to mistakes. To make this
easier and more accurate, a hybrid has been discovered that only produces male progeny (by
crossing male WA yabbies Cherax albidus with female Cherax rotundus yabbies from NSW)"

I've had my first batch of yabbies leave their mum, so I'm now a little obsessed with high stocking rates. I have the entire clutch in a 30 litre tank.

I put the berried female in a cage made of gutter guard so the babies would fall through and wouldn't get eaten (she's back in the sump now). It seemed to work. Babies would let go, spend a minute or so near their mother, then drop to the bottom and never return.

For high density raising, I too have a bit of a problem with battery hen style conditions (even though (or perhaps because) I did some work on a design a few years back. But now I have an idea that I think might work for an IBC.

Basically its a 3D zig-zag of shade cloth or plastic mesh so that there is a minimum of 5cm and a maximum of 8cm between each level. Attach a stack of homes on each level that get larger as they get to the top. All of them should point downhill a bit so food and waste dont get stuck. Feed at the top. Their cookie monster eating habits, and the fact that they seem to eat a meal that has already been through a few digestive tracts (they are bottom feeders) should see the biggest ones rise to the top, and the smaller ones stay safely at the lower levels.

It's a theory.


just for the purposes of science and because I have this little tank on my desk...

Using a conventional single layered approach, how man 2cm yabbies should I be able to grow in 20 litres of water measuring...

length 400mm
width 250mm
height 200mm

?

Anyone? (Charlie)

The advances over the years are quite amazing. I recently found a series of articles on a new process to produces disease free stock. A large part of the process is stripping the eggs from the mother to prevent her passing diseases to the young 'uns..

I don't have links but I am sure you'll find them on some of the AU research websites... I basically found them when looking for articles on the old super strain "walkamin" which now seem to be old hat and replaced by the newer developed strains at tremendous growth rates (Until replaced by something even more tremendous)...

I'd like to see some hybrid of the Tasmanian crawfish and red claws... Hide your children and pets!