breeding crayfish

[crayfish]

Hi everyone. I am new to this site and would like to share what I have learnt about crayfish in the last 4 months. I stumbled across crayfish at a pet shop. It was the first time I had seen a crayfish in Thailand. I knew they were crayfish as I had wild crayfish on my farm back home. After building a small concrete tank I purchaced ten small red ones. The tank had no oxygen supply and no filter system and the crays climbed out of the water and rested on rocks where they breathed air. The wonders of internet taught me a great deal about how to keep and breed crayfish.I soon realized that the crays I had were not the ones to breed commercially as they only grow about 4 inches long and you would need about 60 of them to make up a kilogram. ( Pic 1, dsco4943 ) This one is with eggs ( in berry ). After endless hours searching the www I discovered a breed of crayfish that are commercially viable, they are the Red Claw from Queensland Australia. I purchaced a breeding stock of 2 males and 4 females. This may not seem a large breeding stock but the females lay up to 500 eggs each and if kept well they have a 95% survival rate. I have had these for 3 months and they are about to mate so I am busy building tanks for them. Red claws take about 18 months to reach full size but are easily sellable at 6 months weighing 60 - 70 grams, needing less than 20 per kilo.

Pic 2 dsc04746 is a male red claw weighing about 45 grams. These crays grow fast, they were tiny when I got them and have trebbled size since.The males have a red stripe on their claws. I kept them in a concrete tank at first with air and filter system, they were doing well but I have since moved them to a glass aquarium tank so I can observe them better, it is difficult to see their condition in a concrete tank as they are nocturnal. They are interesting creatures and I spend many hours watching them roam around the tank. Having them in a glass tank also allows you to check on how much food they are consuming, although they like to stash food in their hidyholes for later consumption. They are solitary creatures and need somewhere to hide away from the others. One nice thing about redclaws is the fact that they are not aggressive towards each other in contrast to the small red ones which often fight together loosing limbs. The redclaws eat just about anything but don't like bananas. I make pellets from vegetables, cat food, rabbit food, ricehusks, fruit, fish meat, I grind this to a powder, mix it with water, roll it out on a tray and dry it in the sun then cut it into pellets. They also like to eat chicken bones which is a good supply of calcium. Breeding crayfish is a three stage process. Stage 1 is the nursery. This is where you produce eggs and grow them into juviniles, about 2 inches long. At this stage they can move to stage 2 into bigger tanks to grow to 60 - 70 grams. Stage 3 is selecting ones to grow out to full size preferably on a large pond. Redclaws do not burrow in soil as most crayfish do so this is not a problem, ideally the ones to select for growout are the males as they grow bigger than the females. Pic 3 A redclaw grown out.

Pic 4 Male redclaw ( pic 3 & 4 I have taken off the internet.)

At the moment I am at the halfway mark in stage 1.

When I bought these redclaws I was given 10 craylets about half an inch long ( free). They are now 2 inches long, not sure how many males to females.

If anyone out there is interested in this I will gladly give all the information I know.

Norman

[Sealbash]

Very interested in trying a few when you are ready to sell some

Sent from my iPad using Thaivisa Connect Thailand mobile app

[Showbags]

They are delicious.

I tried to grow some, but they died on me and had dreams of growing a supply to eat ourselves regularly.

Please post more.

There is another type of freshwater cray from Oz found in the Murray River and has spines...it is without doubt the most delicious one available and grows to a good size, sweet and creamy white flesh...mmm

[bunnydrops]

That is interesting. I never thought about farming them. Where I lived in the states as a boy you could get dozens in just a few minutes and throw them in a pot for lunch. They were small. Biggest maybe 5 inches.

[bunnydrops]

One question. Not knowing much about other kinds of crayfish, I got to wondering if there is a problem with water temperature? The ones I know about liked cold water.

[crayfish]

^{Hi Bunnydrops}

^{You ask about water temperature. Crayfish can live from 1 degree above freezing to 34 degrees centigrade. When they go under 10 degrees they go into a state of hibernation, If they actually freeze then they die. Keeping them here in Thailand is safe providing you don't have them in direct sunlight. They need to be kept in the shade and preferably in running water which cools as it flows.}

^{last night one of the females laid eggs, these are the first eggs from the redclaws and made me very happy as I have waited several months for this. I celebrated with a little too much beer.}

^{Keep in touch}

[machans88]

I grew up in north queensland,and for those who don't know,the temperature is almost the same as thailand,red claws would have no problems with the environment.

How did you source the breeding stock?

I live in hua hin and would be interested at starting this up as well.

It would be a hobby and not for profit,and maybe even in corporate it into an aquaponics system,any info would be appreciated.

Red claws are very tasty.

[crayfish]

Hi Showbags

The Murray crayfish is named after the river it lives in. It is the second largest cray in the world, the largest being the Tasmanian Giant. The Murray grows up to three and a half kilos but takes up to 9 years to reach that weight so is not really commercially viable. Also it only breeds once a year as opposed to the redclaws which breed 4 times a year giving between 500 and 1000 eggs each time. Red claws mature in 18 months and can reach 1 kilo. I was pleasantly surprised last night as one female laid eggs, these are the first eggs which I have waited several months for. For the last two days the male has been clearing out all the small stones from his cave and left the floor clear glass, the female is now occupying the cave and the male is sat at the entrance guarding her with his claws open warning the others to keep away. I need to move the female into a tank of her own before the eggs hatch, within a month. I think my real work is about to start.

Thanks for the reply

Regards

Norman

[crayfish]

Hi Machans 88

If you want to keep crayfish for a hobby I would reccommend you keep single sex crays otherwise you will end up with thousands of crays in a relatively short time. One female can produce up to 4000 offspring in a year, half of them will reproduce after 6 nmonths so you can imagine how many you will have on your hands just from one female. Good luck.

You can purchace redclaws from [email protected], not far from you.If you keep them as pets I suggest you keep them in a glass aquarium. I bought a 48 inch tank with filter and airiator for 6500 baht complete with stand. Detailed information about redclaws can be found in the following websites.

[email protected]

www.fish.wa.gov.au

www.cheraxpark.com.au/products/hml

www.aquaculturefarm.com/index.html

www.rirdc.gov.au/pub/handbook/yabbies.html

The Australian government has several good websites and willing to give advice on breeding. They have just finished a 5 year project on redclaws and have produced a new strain called Tolga, they are totally disease free and grow 50% faster than the normal redclaw. I will post more info as I receive it.

If I can help you with any specific info please feel free to ask

Regards

Norman

[Showbags]

^{Hi Showbags}

^{The Murray crayfish is named after the river it lives in. It is the second largest cray in the world, the largest being the Tasmanian Giant. The Murray grows up to three and a half kilos but takes up to 9 years to reach that weight so is not really commercially viable. Also it only breeds once a year as opposed to the redclaws which breed 4 times a year giving between 500 and 1000 eggs each time. Red claws mature in 18 months and can reach 1 kilo. I was pleasantly surprised last night as one female laid eggs, these are the first eggs which I have waited several months for. For the last two days the male has been clearing out all the small stones from his cave and left the floor clear glass, the female is now occupying the cave and the male is sat at the entrance guarding her with his claws open warning the others to keep away. I need to move the female into a tank of her own before the eggs hatch, within a month. I think my real work is about to start.}

^{Thanks for the reply}

^Regards

^Norman

Good luck and bbq at your place in 6 months.

[Farma]

I had a 6' fish tank that I kept them instead of tropical fish in years ago. They provide plenty of entertainment. I used to feed them small pieces of cooked chicken.

I've pondered the idea of breeding them for personal consumption in the village. It's a project that will have to wait until I retire. Haven't been able to convince FIL to get interested in the idea yet.

I'll be watching your breeding project with interest.

[YachtPolaris]

Hi Norman

You post on crayfish is really excellent & interesting. Pls send me message on how I can contact you as I am really interested in the Red Claws....my mobile 0888-383-175

Thank you kindly Tom

[riceyummm]

I wonder if the locals are familiar with them, I've never seen them for sale and many people are reluctant to try new things. They eventually come around though if something tastes good. If crayfish are very prolific you will have to sell some or eat them at every meal and I don't care how good something is......you will get tired of it.

[bunnydrops]

I wonder if the locals are familiar with them, I've never seen them for sale and many people are reluctant to try new things. They eventually come around though if something tastes good. If crayfish are very prolific you will have to sell some or eat them at every meal and I don't care how good something is......you will get tired of it.

I think the Thais would like them. I have seen potato chips lobster favored,very close in taste. But yes you can get tired of them. I lived in Maine one year and ate lobster until I couldn't eat another, that was in 1988. I have only eaten one since. Side note about lobster. Early on it was considered a trash food, the prisons were only allowed to serve it once a week.

[crayfish]

Hi

Last week I was delighted to see my first female with eggs, now I am double delighted as I now have two with eggs. This weekend I have worked nonstop to put together a tank that I hoped would work, and it did. The design for this tank I got from this farming forum ( concrete tanks for fish ) . I have made a few changes as you can see in the following pics.

Pic 5232 Shows the water inlet to the column filter, the water swirls around and the heavy particles are pushed to the sides of the tank

pic 5234 The tank on Saturday morning under construction

pic 5239 The system works. The pump on the far left is sucking water and the overflow pipe on the right is pushing water causing a really good current which is perfect for crayfish, it duplicates their natural environment which is fast flowing rivers.

pic 5241 Besides creating a water flow the overflow pipe also provides a free air supply without the use of an airpump, one thing less to maintain.

pic 5245 The set up

pic 5250 Cray fish are great escape artists. If there is a way of getting out of a tank they will find it. I kept the redclaws in this tank a month ago, just a bare tank with no filter system and no air supply, they were doing well but the tank needed to be cleaned regulary which involved taking the crays out along with the stonsd, it was a lot of work. This new system is more or less maintainance free( I hope ) I thought I had the old tank sealed and there was no way they could get out. One evening I was sitting at the front of my house having a quiet beer or two when I saw three crays walking towards the house. I realized they can climb up concrete and out they go. The new tank, as you can see from this pic has an aluminium "L" strip which I have screwed on. The thought here is that the crays can still climb up the concrete but can't climb upside down on the underside of the aluminium and escape,( I'll let you know for sure later). It is very important not to let the crays escape as they can create havoc with the natural waterways, rivers, ponds etc.

pic 5249 On top I have laid a plastic netting, not to keep the crays in but to keep predators out, including young children that are all facinated by them.Predators include toads.large frogs, tookgairs and possibly snakes.

I live in a small village where the residents are all rice farmers and they have never seen a crayfish before. They ask many question about them such as " are they edible?, "what are they?" "Where are they from?" Why do you keep them? They see six crays in the tank and think I am keeping them as pets,I have to explain that these are breeding stock and will produce 30,000 in one year which is what I am aiming at.

I have four females, two are in berry and the other two will be within a week, so by next weekend I will have 2000 eggs that will hatch out in 4 to 6 weeks.

The tank I built last weekend will hold 500 craylets, so I have to build three more tanks to accommodate them all. They can stay in these tanks for about three months and will then need a bigger tank so I will need to make a really big tank and put them all in. At 6 months oud they weigh between 70 and 90 grams and can be sold, or they can be grown out in a large earthen pond for another year and reach 1 kilogram and sold to upgrade restaurants. I have no worries about the market. Everytime my wife sees them her mouth waters, I have told her that if she eats one I will put her in the tank to replace it. She often asks me why they are taking a long time to grow, the village people are use to quick returns on their investment as they need the money back fast. I am not a rich man but I can wait. I feel this is worth waiting for.

Another thing I have to consider is maintaining the supply to customers. This involves a continious breeding program. Restaurants would not be happy if I supply for a month or two and then run out.

pic 5226 Male trying to climb out of the tank, it can get a grip on the silicone

Will continue later, have to do some work not related to crayfish, boring!!!!!!

Regards

Norman

[bunnydrops]

Keep us informed. I think you are on to something here. Food supply for them I see as the only problem. Cat and dog food I think could be expensive. Maybe at the market, you could get the fish or maybe even the pork sellers to give you their scraps. Do they eat rice?

[crayfish]

In answer to bunnydrops asking about food for the crays. Well, at the moment it is not a problem as I only have a few crays. But what happens when I have thousands. The one thing to avoid is putting fried food in their tank, or indeed any oily food. The oil will dilute with the water and will clog the gills of the crays and they will not be able to breath, and will drown.I have read many articles about people feeding them on cat and dog food. One, it is expensive and two, I like to know what I am feeding them. In pet food I don't know the fat content. Making food for the crays is easy and not very time consuming. Basically I boil vegetables and a little fruit,together with raw fish and chicken meat. It only wants to be boiled for a minute or two or the vitanin and calcium will all be in the water. I then grind it all in a blender, mix it with rice husks, roll it out like a pizza base and dry it in the sun. This can either be cut into pellets or just broken off as needed. They don't seem too keen on eating rice,and it clouds the water with starch. They like eating decomposing food so I put leaves from cabbage, lettuce etc in the tank and as it decomposes they eat it.

Will talk again on this subject, I'm still learning.

Regards

Norman

[David48]

Mate, an excellent thread ...

I am sure that many, like me, read it with interest.

[crayfish]

Hi Everyone.

Today I am in a bit of a dillema with the crays. At the moment I have 2 glass aquarium tanks, one big 48 inch, and a small one. In the big tank are the big breeding stock, two males and four females. two of the females are in berry and the other two will be very soon, so within six weeks I will have about 2000 baby crays( craylets ). Where do I keep them???? I want to keep each family of craylets seperate. For the past few days I have been designing a nursery set up for them which involves four plastic large food containers, side by side and plumbed up to a filter system. I have just come back from Makro . They have food safe containers but smaller than I am looking for. The big plastic containers are not designed for food and are likely to release chemicals into the water which will kill the crays. Anyhow I have purchaced one food container and have come up with another idea, which is to suspend the container in the big aquarium tank. First to cut slots around the sides, cover the slots with mesh and suspend it.The slots will allow the airiated water to flow through. In theory this should work. Will set it up tonight and put a female in berry in to see how she copes with it. I really hope this will work as it will save building a complicated nursery and will help utilize the big tank.

The raceway tank is up and running. I have had to make a few modifications though. The current was too strong, I put about 50 small fish (guppies) in to see how they handled it and they were being swept around the tank at some speed. To slow the current down I have placed some stones around the raceway and adjusted the pump outflow regulater to slow the water output from the pump. That has worked well. At the weekend I will put the 10 juviniles from the small aquarium tank in. They are about 2 inches long and will stay in the raceway tank for another few months until they are ready to breed. They will be my second generation breeding stock. This will also free up a tank which I can use for one of the females in berry ( with eggs ). The saying "in berry" comes from the fact that the eggs look like a berry ( Raspberry) see pic. A lot of experimenting going on at the moment. I have been experimenting with one thing or another since I started this project and so far have not lost a single cray

.

Will attach some pics of the females in berry soon.

Regards

Norman

[ozzydom]

In answer to bunnydrops asking about food for the crays. Well, at the moment it is not a problem as I only have a few crays. But what happens when I have thousands. The one thing to avoid is putting fried food in their tank, or indeed any oily food. The oil will dilute with the water and will clog the gills of the crays and they will not be able to breath, and will drown.I have read many articles about people feeding them on cat and dog food. One, it is expensive and two, I like to know what I am feeding them. In pet food I don't know the fat content. Making food for the crays is easy and not very time consuming. Basically I boil vegetables and a little fruit,together with raw fish and chicken meat. It only wants to be boiled for a minute or two or the vitanin and calcium will all be in the water. I then grind it all in a blender, mix it with rice husks, roll it out like a pizza base and dry it in the sun. This can either be cut into pellets or just broken off as needed. They don't seem too keen on eating rice,and it clouds the water with starch. They like eating decomposing food so I put leaves from cabbage, lettuce etc in the tank and as it decomposes they eat it.

Will talk again on this subject, I'm still learning.

Regards

Norman

25% protein is recommended for redclaw so why not use sinking 25% herbacius fish pellets?

[Sealbash]

Excellent information and extremely interesting project. Please do keep us updated

Sent from my iPad using Thaivisa Connect Thailand mobile app

[canuckamuck]

Keep the info coming Crayfish.

[teletiger]

Hi Everyone.

Today I am in a bit of a dillema with the crays. At the moment I have 2 glass aquarium tanks, one big 48 inch, and a small one. In the big tank are the big breeding stock, two males and four females. two of the females are in berry and the other two will be very soon, so within six weeks I will have about 2000 baby crays( craylets ). Where do I keep them????

Regards

Norman

Send a few to me. I've got a 6ft tank coming free in 2 weeks.

Regards.

[ozzydom]

Very interesting article from FOA on redclaws

http://www.fao.org/fishery/culturedspecies/Cherax_quadricarinatus/en

[crayfish]

My thanks to Ozzydom for the enclosed fact sheets on redclaws. I have read about 30 such documents and the problem I have with them is that there is so much conflicting information. In this report it states that redclaws grow up to 500 gram (males), I have read in several other documents that they grow to 1000 gram ( 1 kilo ) I will have to wait and see. The document also states that it is not necessary to have a hatchery, which is what I am building at the moment. It may not be necessary but if I don't use one I will loose a lot of the craylets with overcrowding in the aquarium tank. I can't picture a 4 foot tank with 2000 craylets in it. In the document they say that the craylets can be put in earthen ponds at 2 weeks old. At this age they are tiny, I am sure many would perish at that size. I like the idea of using earthen ponds to grow the crays out, starting when they are about 6 months old and weighing 50 grams and growing them out to full size ( whatever that is ). The pics in the document are very good and informative, already given me some good ideas.

Again many thanks for the doc, keep them coming.

Regards

Norman

[David48]

My thanks ..

Norman

Hi there Norman ... some great work there.

Just a small thing ... notice the difference in the writing size between everyone elses ... and yours.

The Admin guys on the Forum, have to keep coming to the thread and change yours.

Maybe just type it in the box here and it's easy enough to read.

[DerkMR]

Hi Norman,

as far as I remember from breeding crayfish and shrimps as pets the young ones need animal proteins to grow, so no way to get them starting with your mostly vegetarian homemade food.

But there is a good option at least up to some quantity and this is called "Moina". It's a genus of aquatic plankton and being sold in pet shops which have a good variety of fish. In Udon Thani I know only one but normally you can ask for breeders of siamese fighting fish (pla kat) and they should have some in culture.

All they need for good reproduction is a lot of sunlight to have a lot of phytoplankton to feed on. Usually they are bred in the concrete rings used for the large water pipes available at builders shops for THB 150.-, just take some cement and fill the bottom so that it's a closed container and fill it with water. Some liters taken from a public lake will help growing the plankton faster. When it's nice green you can add some Moina and the quantity will explode within 1 or 2 weeks.

Bye,

Derk

[4u2mad]

Hi Everyone.

Today I am in a bit of a dillema with the crays. At the moment I have 2 glass aquarium tanks, one big 48 inch, and a small one. In the big tank are the big breeding stock, two males and four females. two of the females are in berry and the other two will be very soon, so within six weeks I will have about 2000 baby crays( craylets ). Where do I keep them???? I want to keep each family of craylets seperate. For the past few days I have been designing a nursery set up for them which involves four plastic large food containers, side by side and plumbed up to a filter system. I have just come back from Makro . They have food safe containers but smaller than I am looking for. The big plastic containers are not designed for food and are likely to release chemicals into the water which will kill the crays. Anyhow I have purchaced one food container and have come up with another idea, which is to suspend the container in the big aquarium tank. First to cut slots around the sides, cover the slots with mesh and suspend it.The slots will allow the airiated water to flow through. In theory this should work. Will set it up tonight and put a female in berry in to see how she copes with it. I really hope this will work as it will save building a complicated nursery and will help utilize the big tank.

The raceway tank is up and running. I have had to make a few modifications though. The current was too strong, I put about 50 small fish (guppies) in to see how they handled it and they were being swept around the tank at some speed. To slow the current down I have placed some stones around the raceway and adjusted the pump outflow regulater to slow the water output from the pump. That has worked well. At the weekend I will put the 10 juviniles from the small aquarium tank in. They are about 2 inches long and will stay in the raceway tank for another few months until they are ready to breed. They will be my second generation breeding stock. This will also free up a tank which I can use for one of the females in berry ( with eggs ). The saying "in berry" comes from the fact that the eggs look like a berry ( Raspberry) see pic. A lot of experimenting going on at the moment. I have been experimenting with one thing or another since I started this project and so far have not lost a single cray

.eggs_fs.jpg

Will attach some pics of the females in berry soon.

Regards

Norman

Thai Wasado (KK) have some big blue plastic containers, round and square, lids available separately. Kind of size you might use to provide water for livestock in a field. Any good?

[crayfish]

Hi Derk

Thanks for the advice on the aquatic plankton. I have an idea where I get get some so will check it out later today.

Although the food I make is mostly vegetarian I do supplement their diet with raw meat, fish, chicken, and liver and heart. I also feed them on "jing lee" ( don't know the english word for this) but it is like a fat grasshopper, also other insects. These are high in protein and calcium.I already have the concrete rings which I am using for the filter system which is in full sunlight. Will give this a try. Thanks for the info. Will keep you informed as it progresses.

Regards

Norman

[crayfish]

Last night I read two more documents regarding breeding crays. One from America and one from Australia. They both, like most of the documents I read, give figures on how to maximise

output with maximum profit and maximum intensive housing. One recommended certain types of antibiotics and growth promoters . This is not the way I want to go. If I need antibiotics and growth promoters then I think I am doing something wrong. The crays I have now are growing well and are in a healthy condition without all the additives. The documents leave me thinking they are running a crayfish factory not a crayfish farm. I am not getting this together to become rich, that has never entered my mind. I just want to breed crays in as natural an environment as possible. I might be wrong but I believe if they are living stress free lives they will grow and stay healthy, much the same as us humans.

Speaking of natural environments for the crays, I feel that a glass aquarium tank is not a natural environment for them. It is good for observing them but they are also observing us through the glass. This became apparant last night when a dog went up to the glass for a look in and the crays panicked and hid really fast. Today I will blank out the bottom 6 inches or so all around the tank . In their natural environment they spend the day hidden away from predators by hiding in dark places such as alcoves or caves where nothing can see them. In the tank as it is now they are open to view which must be stressing them somewhat. Another thing they don't like is the small pebbles I put in the tank. The two females with eggs are living in caves with no pebbles, the male cleared all the pebbles out before they laid eggs.The reason for this is that the pebbles can damage the eggs as I am sure a lot of them have sharp edges, Also when the females walk around the tank they keep their eggs well covered with their tails tucked over the eggs. I get my camera back today so I will take some pics this weekend and post them next week.

Just a point of interest,,, I often wondered why the back most legs of the crays don't have claws like all the other legs. This I found out by observing the females with eggs, they actually use their back most legs to clean their eggs, they wipe them and shake them, if they had claws they would rip the eggs apart.

I have tried to upload some videos I have taken but I see the max single file size is 100MB, will contact thaivisa staff and ask for a larger file size.

Have to go

Regards

Norman