Re: [IOBB-IBS-FORUM] Re: cray fish and freshwater clams/mussels

[DOCN...@aol.com]

In a message dated 11/21/2008 4:58:45 PM Eastern Standard Time, jackso...@yahoo.com writes:

Hi Jacky,   Can Nelson Hendler provide some technical information  on their crayfish rearing project. How are the ponds constructed? what is used in feeding the crayfish?, any articifial system to control water conditions? are there specialized organs providing the young crayfish at the initial stage of the project?. This project sounds lucrative and can be promoted in coastal areas of Cameroon where over fishing has greatly reduced the availability of sea products with prices sky rocketing including that crayfish.    Jackson Ntapi Heifer International Cameroon PO BOx 467 Bamenda Cameroon CellPhone: +237 96134784

Dear Mr. Ntapi:

 

I shall try to answer each of your questions in turn.

1) determine if the soil where you want to place your ponds has a high clay content. The higher the better. This means it will hold water.

2) the ponds are constructed is a simple fashion...

    a) determine the number of acres or hectres that you want for ponds.

    b) lay out the pond area using stakes and lines (ponds).

    c) go around the entire perimeter of the pond area with another outline about 10 meters wide (moat)

    d) begin by digging the moat, and use the dirt from the moat to build the walls (berms) of the ponds.

    e) build the berms as high as you want the ponds to be deep. If you want 1 meter deep ponds, constuct

        the berms 1 meter high.

    f) build stand pipes into each berm, so you may raide or lower the water level in each pond.

    g) dig a well and have the well water empty into the moat.

    h) pump the water from the moat into each of the ponds.

    i) set the stand pipe to adjust the height of the water you want in each pond, and have the run-off from the

       pond flow back into the moat.

3) Crayfish fed on rotting vegetable matter (detritus) or left over animal parts from a slaughter house.

    However, there are disease problems with the latter, so it is better to use left over grain or stalks.

4) The crayfish ponds can be used to grow a grain crop, such as millet or milo, and the grain crop can be

    harvested, and the left over plant material feeds the crayfish.

5) other freshwater species can be grown with the crayfish, depending on locale.

6) Each crayfish delivers 350 young.

 

When I was operating, I would buy 2,000 pounds of crayfish for release into the ponds in March, and by October, I would harvest 20,000 pounds in the same year.

   

This system used the minimum amount of water, and recirculates the water. This also oxygenates the water, and this can be supllimented with Ice Eater - Powerhouse aerators.

 

I am available for consultation on the contruction of such a system. Please look at the aerial photo of my farm at www.DuckHuntingFarm.com to see what the ponds look like.

 

I hope this will help you.

 

Sincerely,

 

Nelson Hendler, MD (docn...@aol.com)

---

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[jackkson ntapi]

Dear Nelson, Thanks for the details, it will definitely be of help if i have an opportunity of implementing such a system. My main concern now is the availability of the parental caryfish. Are there specialized suppliers of reproducers? that should be lacking here in my area. I suppose the crayfish are fresh water species, can one obtain crayfish from rivers in an area and create a pond to produce parents to supply farmers in an area. Please this is a petinent issue as the sustainability and growth of such an activity will strongly depend on the supply of the initial parent material. Also any information or issue on optimum sex ratio in the ponds?   This is one facinating environmentally friendly integrated project that can be used in poverty alleviation in my area if properly implemented. If i can have information on sustained supply of parental material, i will reach out to local farmers and discuss the feasibility of starting such a project.  I am still browsing through photos of your farm, quite interesting.   Jackson Ntapi Nk. Specialist in integrated agriculture PO BOX 1020 Yaounde Cameroon Cellphone (237) 613 47 84   --- On Mon, 12/1/08, DOCN...@aol.com <DOCN...@aol.com> wrote:

[DOCN...@aol.com]

Dear Jackson:

 

By all means, please do use local crayfish, instead of any imported variety.

 

Apparently, from what I have read, various parasites and funguses grow on the gills of crayfish, and importing a foreign source may kill off the native populaton. This happened in Sweden.  

 

I do not know the optimal sex ratio but I must assume that the crayfish are not monogoomous, and that a single male might handle multiple females. My inclination is just to catch whatever you can in the wild, and throw them into the ponds. You could pay people a small amount to bring in wild crayfish, and use this as the breeding stock for the ponds, and then sell the aquaculture product. This hopefully would help the economy in three ways  1) payment for the wild caught crayfish, and then 2) a 10 fold increase in what was wild caught and introduced into the ponds, sold as aquaculture product.3) jobs for the people catching the farm raised crayfish.

 

It took 2 people 3 hours to empty and re-bait the 800 crayfish pots on my farm, and they did it twice a day. In between, they sorted and packaged the crayfish, and stored the surplus in storage tanks with running water, to sell the next day or two. They have to be separated to some degree because they will eat each other.  

 

The type of trap and the type of bait is of most important. We used a pyramid trap which is three sided, and had three openings at the bottom, and used an oily fish for bait.

 

I have spent a lot of time in Kenya, South Africa, Botswana, Zimbabwe, and Swaziland, on hunting trips.  I would be happy to serve as a technical advisor for any project for you. If you can arrange for me to travel to Cameroon, I would love to come. Maybe I might even be able to squeeze in a hunt for bongo, for which Cameroon is so famous.

 

Best wishes.

 

Nelson  (Nelson Hendler, MD)

I am available for consultation on the contruction of such a system. Please look at the aerial photo of my farm at http://www.duckhuntingfarm.com/ to see what the ponds look like.

I hope this will help you.   Sincerely,   Nelson Hendler, MD (docn...@aol.com)

[Michael Theroux]

Hello all - fascinating discussion of late, but I can foresee problems in long-term sustainability. Here is an interesting parallel that might inform:

 

Pressure for salmonid species grown in inland (loch) fisheries in Scotland have over the last two decades seen such increased, forced production that fish waste accumulation surpassed rates of natural cleaning for these slow-moving bodies of water. Feces pollution impacted fish meat quality and general health, and in some cases brought operations to a halt. A common "family-owned" loch might be 2 miles long, but only one quarter mile across, with limited inflow and outflow. Natural cleaning, if all fisheries were stopped, would take over a decade, which would bankrupt most families. With our concept, cleaning could be accomplished while very limited fisheries continued, within about three to four years. Once satisfactory nutrient and water purification cycling was established, the overall bio-system should self-maintain. Although the lochs are very much deeper, perhaps something of this idea might advance crayfish pond design sustainability.

 

Outlining our concept:

• First year: Build a "wetland" bio-filter of native reeds, cat-tails, willows and such along the in-flow, preferably on a bed of crushed rock or other porous matrix over a more impervious sub-layer (once again, the value of clay is seen). Match initial planting to natural water flow, intercepted and diverted through matrix.
• Second year: Install low-flow pumps to circulate the watery sludge from the farther end of the loch, up and through the wetland.
• Third year: Coppice the willows and typha, first crop during third year of growth. Combust or gasify biomass for heat recovery and steam generation, for combined heating, cooling and power sufficient to run fish processing operations and family home needs.
• Fourth year: Water cleaning should be evident; adjust pump rates as needed. Adjust extent and species of wetland biofilter after first harvest, to match and balance production-sourced biological oxygen demand of the recirculated water, testing effluent before and after biofiltration.
• Adjust scale and efficiency of conversion after second harvest, perhaps increasing to second train or improving base system, as economics allow.

Note: We never succeeded in finding a site and building a first demonstration unit; maybe some of what we learned can be of help now to your efforts.

 

Best of luck,

 

Michael Theroux, V.P.
JDMT, Inc.
PO Box 7838
Auburn, CA  95604-7838
530-823-7300; cell: 530-613-1712
email:  mthe...@jdmt.net

Skype:  michael_theroux

---

From: iobb-ib...@googlegroups.com [mailto:iobb-ib...@googlegroups.com] On Behalf Of jackkson ntapi
Sent: Monday, December 01, 2008 11:58 PM
To: iobb-ib...@googlegroups.com

[DOCN...@aol.com]

Dear Michael:

 

What you have outlined for salmonid species sounds fascinating, and biologically sound. Actually it is very impressive and well thought out.

 

However, as you know, salmonids are fairly oxygen and water quality sensitive. Also, the water flow in the situation you described is rather restricted.

 

There are differences in the aquaculture of crayfish  versus salmonids, which may make the project viable for a emerging nation.

 

1) the depth of the water needs for crayfish aquaculture is only 2-3 feet.

2) the feces actually will serve as a nutrient for whatever grain crop is grown in the same ponds,

3) the additional of fresh-water mussels serves as an additional filter

4) the pond system I described is a closed, re-circulating system, that uses regulated water flow and Powerhouse propeller aerators to oxygenate the water, thereby reducing any chance of fecal polution. You can always increase water flow to improve oxygenation.  

5) crayfish are amazingly hearty. I used to ship crayfish from Baltimore to London, packed in wet newspaper. After 5 days from date of shipment to day of pick-up, the mortality was only 3%.

6) crayfish are not really oxygen sensitive.

 

Triple cropping the artifical ponds with 1) crayfish, 2) plants such as millet, and 3) a freshwater bivalve for filtering really enhances the income per acre.

 

We used to drain the ponds each year, plant the pond bottom, and then flood and restock with crayfish.

 

In a different vein, when my friend Mike Hooker, PhD was president of Uni. of Maryland..Baltimore Campus (UMBC) he created a business incubator facility. One of the people had a project for "grow hormone pulsing" for salmon, and trout. I think his name was Sam Grillo, PhD, but I am not sure, since this was over 20 years ago. Apparently the amino acid sequence for the growth hormone of most salmonids is the same ranging from trout to any type of salmon. Sam was pulsing the growth hormone into the water at a critical stage 2 or 3 times in the early growth of the fish, and got a 50% increase in the final product. I don't know how this may impact on your work, but I hope it helps.

 

Best wishes,

 

Nelson  (Nelson Hendler, MD, MS).

 

In a message dated 12/2/2008 2:04:02 PM Eastern Standard Time, mthe...@jdmt.net writes:

Hello all - fascinating discussion of late, but I can foresee problems in long-term sustainability. Here is an interesting parallel that might inform:

 

Pressure for salmonid species grown in inland (loch) fisheries in Scotland have over the last two decades seen such increased, forced production that fish waste accumulation surpassed rates of natural cleaning for these slow-moving bodies of water. Feces pollution impacted fish meat quality and general health, and in some cases brought operations to a halt. A common "family-owned" loch might be 2 miles long, but only one quarter mile across, with limited inflow and outflow. Natural cleaning, if all fisheries were stopped, would take over a decade, which would bankrupt most families. With our concept, cleaning could be accomplished while very limited fisheries continued, within about three to four years. Once satisfactory nutrient and water purification cycling was established, the overall bio-system should self-maintain. Although the lochs are very much deeper, perhaps something of this idea might advance crayfish pond design sustainability.

 

Outlining our concept:

• First year: Build a "wetland" bio-filter of native reeds, cat-tails, willows and such along the in-flow, preferably on a bed of crushed rock or other porous matrix over a more impervious sub-layer (once again, the value of clay is seen). Match initial planting to natural water flow, intercepted and diverted through matrix.
• Second year: Install low-flow pumps to circulate the watery sludge from the farther end of the loch, up and through the wetland.
• Third year: Coppice the willows and typha, first crop during third year of growth. Combust or gasify biomass for heat recovery and steam generation, for combined heating, cooling and power sufficient to run fish processing operations and family home needs.
• Fourth year: Water cleaning should be evident; adjust pump rates as needed. Adjust extent and species of wetland biofilter after first harvest, to match and balance production-sourced biological oxygen demand of the recirculated water, testing effluent before and after biofiltration.
• Adjust scale and efficiency of conversion after second harvest, perhaps increasing to second train or improving base system, as economics allow.

Note: We never succeeded in finding a site and building a first demonstration unit; maybe some of what we learned can be of help now to your efforts.

 

Best of luck,

 

Michael Theroux, V.P.
JDMT, Inc.
PO Box 7838
Auburn, CA  95604-7838
530-823-7300; cell: 530-613-1712
email:  mthe...@jdmt.net

Skype:  michael_theroux

[Michael Theroux]

Dear Nelson, I see that you overcome potential pollution via grain cropping; you accomplish the same as our biofilter, but en situ. Nicely designed.  MT

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From: iobb-ib...@googlegroups.com [mailto:iobb-ib...@googlegroups.com] On Behalf Of DOCN...@aol.com
Sent: Tuesday, December 02, 2008 11:27 AM

To: iobb-ib...@googlegroups.com
Subject: [IOBB-IBS-FORUM] Re: cray fish and freshwater clams/mussels

[DOCN...@aol.com]

In a message dated 12/2/2008 2:35:37 PM Eastern Standard Time, mthe...@jdmt.net writes:

Dear Nelson, I see that you overcome potential pollution via grain cropping; you accomplish the same as our biofilter, but en situ. Nicely designed.  MT

Dear Michael:

 

I appreciate your kind comment. Best wishes, Nelson

[David Del Porto]

Excellent idea Michael:

 

My firm designs and operates the type of systems you outlined and so we have the hands-on experience and test data to validate your approach.  If there is a specific site for which influent characteristics can be developed; we would be pleased to provide a preliminary sizing of the system.  One caveat: The wetland system needs to be two alternating systems.  We have seen our subsurface flow wetlands clog over time even with harvesting of the biomass.  Each should be sized to manage the total flow.  The management plan would allow one to be used while the other is drained to allow aerobic decomposition and/or flushing to clean out the accumulated sludge.  It does require management, so it's not exactly self-sustaining.

 

All the best,

--
David Del Porto
Ecological Engineering Group, Inc
www.ecological-engineering.com
Office Phone:            
   978 369 9440 ex 101
Del Porto's Direct Phone:
   617 431 4341
Fax:                            
   617 209 1200
Short bio: http://www.ecological-engineering.com/delporto.pdf

[Michael Theroux]

David, nice match-up of expertise: my focus has been on identifying and advancing systems for ultra-clean thermal conversion of biomass and waste, integrated into other biotech approaches. I can see that choices for effluent flow delivery would be highly desirable. And I suppose I look at "sustainability" as including on-site operations and maintenance, but I would agree that is not the same as "self-maintaining", as I had stated in my outline.

 

It has been quite some time since my work with Scottish fisheries; anyone within IOBB in contact on this issue, or with similarly challenged sites? This could be a good subject for a focused on-line working group exercise.

David, my contact information is below; perhaps we could also discuss the "business" side, off-line.

Michael Theroux, V.P.
JDMT, Inc.
PO Box 7838
Auburn, CA  95604-7838
530-823-7300; cell: 530-613-1712
email:  mthe...@jdmt.net

Skype:  michael_theroux

 

 

---

From: iobb-ib...@googlegroups.com [mailto:iobb-ib...@googlegroups.com] On Behalf Of David Del Porto
Sent: Tuesday, December 02, 2008 11:57 AM

[David Del Porto]

Michael:

 

I'm very interested in business collaboration.  My personal focus has been recently (since 1995) on total utilization of effluent via designed and permitted evapotranspiration systems.  Since 2004 I have been developing what I call the Green Paradigm of using wastewater to grow energy crops on barren land and just began the search for pilot communities (see attached).  It would seem we have compatible interests.  We could grow feedstocks for your thermal conversion systems.

 

Regarding IOBB:  I met Jackie Foo in Samoa some years ago and we have been in contact from time to time.  However when I took on the design and construction and operation of larger scale Solar Aquatic Systems, I was not able to be more than a passive participant.

 

Let me know your thoughts on how we could develop the relationship further.

 

All the best,

[CA...@aol.com]

In a message dated 12/3/2008 11:13:59 A.M. Central Standard Time, mthe...@jdmt.net writes:

David, my contact information is below; perhaps we could also discuss the "business" side, off-line.

Michael Theroux, V.P.
JDMT, Inc.

--------------------------------------------------------------------------

Michael, if you are going to work on a business plan for this technology, I would like to be included.

 

Neal Van Milligen

Bioten Power and Energy Group

www.biotenpower.com

ca...@aol.com

---

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[jackkson ntapi]

Hi Nelson,   Sorry for the late reply, actually relocating from one province in Cameroon to another as i recently changed job. A very delightful message from you with good technical insights. Of cause if such a  project is implemented your technical support will be highly wellcomed. we are intending to implement a development project in which local farmers will run the ponds in their farms and use proceeds from the activities to improve their livelihood. In the project proposal document i am currently working on to be used in obtaining funds for the project, we intend to help local communities to establish and manage breeding stocks from which farmers within the community will buy their production stocks. The project coordination unit will only provide technical assistance to farmers and help in the development of adapted marketing strategies. Well we are still a long way from this, but i think it is wise to involve a package for technical support from external sources in the proposal. Will be great hunting in Cameroon, a lot of game parks from the North to the South of the country will certainly love it. Imagine hunting in a country that posseses the rich fauna of the grassland of Kenya in the North, the diversified forest fauna of the amazonian forest in the south. It will definately give you a lot to look for, but i am sure you will be very surprised why the local people are so poor despite these abundant natural resources. Kind regards.

Jackson Ntapi Nk. Specialist in integrated agriculture

Coordinator Esperance-Essor-Estime group PO BOX 1020 Yaounde or 171 Melong, Cameroon

Cellphone (237) 613 47 84