Building a Floating Net Platform for Lobster 'grow-out' Aquaculture #2

[jamesmusslewhite]

  

   This time last year we were knee-deep in the craziness of virus scares, long extended lock-downs and the whole of the lobster industry forded to close. But this year has found me knee-deep in several small mariculture projects.

   During the seasonal rainy-season I began (January-February) to disassemble the two large nets of the floating bamboo platform. This will be the primary topic of this new forum thread, but two other smaller projects are also being worked on alongside this one. And as such probably need to be mentioned as they too relate to this project. So I will give a short rundown for clarity sake, and familiarity as they will surely be discussed as this forum thread progresses. The bamboo floating platform has simply become too unstable, and needed to be completely replaced. So during the rainy season those two large nets were dragged to the shallows, where they could be properly cleaned and then stored away until needed. The floating bamboo frame was then completely torn-down, and the plastic 55gallon drums were cleaned and put away. While that task was completed, we focused on the collecting of needed woods and materials for the next task on our ever-growing ‘to-do’ list.

  Last year we decided to sell our other pole-hut facility that we constructed four years ago. This pole-hut was primarily built to house a couple of emergency nets, and serve as a security shack during those time when in use. Having such a place in stand-by, allows one to quickly relocate large quantities of housed stock if needed. Such as emergency net rips, tares or unexpected structural damage to the hut. This is a protocol I have always followed; as sea-bugs are both clever and quick, and within mere hours can find 500 little Houdini’s and Elvis’s have left your building. It was my following this protocol two years ago, which greatly helped reduce mortality-rates of my own housed stock. At the time I was weekly randomly selecting individuals to inspect measure and weigh. I noticed the lobsters where not acting normally, so I use all my available nets to quickly begin separating them into smaller groups. This allowed it easier to identify, isolate and quarantine individuals. Within two days I was having mortalities. Body/head separations and quick loss (separation) of appendages; my only sure diagnoses at that time was, this shit ain’t normal! I took photos to document, packed the cadavers on ice where they were driven down to a lab in Butuan. They quickly sent the results confirming we in Day-asan were facing a devastating outbreak of the ‘White spot syndrome virus (WSSV). Caused by contaminated shrimp shipped up from the Morolands to Butuan, where they we then bleached and chemically-treated and sold to unsuspecting lobsters growers in our region. Criminals trying to turn a fast peso…

   The Fisheries recommended the emergency-harvest of all housed stock, and decontamination of all nets, pens, cages and enclosures. Most facilities had mortalities in excess of 80%, many had 90% or total loss of housed stock. Grower could not sell their housed stock, as this region was basically black-listed by market buyers. Many of the growers were totally whipped-out, some left holding millions of pesos worth of sick dying stock in their facilities. Then the following season the China-virus shutdown the industry most of the year. As for myself, my own housed stock mortality-rate was less than 30%, with a return of their natural exoskeleton coloration and overall shell luster. That I believe is due to a second protocol I have always followed. I also maintain a strict policy of daily meal rotations, by always providing a wide varying diverse diet, which means meals are rarely duplicated during a three-day feeding regiment cycle. I had purchased a quantity of those same contaminated, but my stock was only given a heavy feeding only once in three days. My stock was not gorge-feed those s, rather they were  fed a wide variety of both saltwater and freshwater species. So they are leaner, meaner and muscular helping them to maintain a strong amunity. So were my mortality rates that low due to the first protocol? Due to my second feeding proposal? Or that I was lucky they ate less contaminated shrimp-heads? My own hypothesis is that it was probably due to all the above, with a little dumb-luck thrown into the mix.

   Tomorrow morning I am supposed to be receiving our first delivery of 300 pueruli (fingerlings), and either Thursday or Friday morning we are expecting another 300 pueruli coming from Dinagat Island. So even though the structure of our new pole-hut is still under construction, we are already ready for the arrival of our first 600 little playful sea-bugs. We plan at first just use this new pole-hut to house those first 600 pieces, while I am building the new floating net platform. I have already finished the final designs of the framework of the floating platform. It will be approximately the same dimensions is the old bamboo platform, but constructed out of a saltwater resilient hardwood. This will allow for a lighter stronger overall frame, while providing a much longer-lasting framework. The platform will use the same 55-gallon drums and also the two large nets. It should able to easily house 700 marketable size (500gram) Juvenile-adults, or 500 marketable-size (1,000gram) individuals. I should have the floating net platform completed and anchored to the seafloor in less than two months. The timing should work out nicely with those 600 individuals, which will soon be housed under in the new pole-hut.

   After their relocation to the big nets of the floating platform, the pole-hut will be exclusively used for quick pueruli (fingerlings )rollover production. This facet of the lobster grow-out industry, is referred to as a specialty grower.  A grower (me) will purchase early-stage pre-Instar (moult) pueruli , for the sole purpose of short-term grow-out of those individuals. The grower then houses those delicate little sea-bugs for a period of (2-3 additional months). Then the grower resells the larger stronger early stage Algal-juveniles individuals, at a reasonable markup to other lobster growers. That grower (me) fully understands that historically there is a 40% to 60% mortality rate during that first instar (moult). And the survivors will be housed and fed for another 2+ months. Some call the practice ‘Lobster Roulette’. The grower (me) does not get rich flipping those small sea-bugs, but it can have two benefits. A.) generates additional cash flow. B.)That not sold merely needs to be further raised to desired market weight. I will be jumping through hoops for a while, while loving every minute of it.

    I still have the pole-hut to finish, a floating net platform to start and finish in less than eight weeks, and I have already started working on the designs for a much larger multi-net floating platform, to be used for multi-cropping fish, crustaceans snails, slugs and seaweed species.   

Edited May 12, 2021 by jamesmusslewhite

[jamesmusslewhite]

   So now that the OP has given readers a brief synopsis of the going-on during the last two lobster seasons. As well as a general idea of the particulars of this new mariculture-aquaculture project, it is time to roll-up the sleeves and get down to the ‘brass tacks’. Yes later this season I must do major repairs and refurbishing of my boat ‘Arthur 1’, so expect brass-tacks mentioning as this thread progresses.

   Some reader may not know what is ‘mariculture’ and how does it differ from ‘aquaculture’? That is quite easy to explain, ‘Mariculture’ is merely a specialized branch of aquaculture. Mariculture is commonly referred to as ‘marine farming’. It is basically just aquaculture, but differs in that it involves cultivating marine organisms for food and other products.    

   Over the next 14-16 months these happy playful little sea-bugs, will grow and physically transition, from the size of a pinky-finger (3grams), to becoming (800gram-1,000gram) adults capable of chewing through a bean-can. This means their dietary constantly requires monitoring and understanding what food-types are appropriate at their specific developmental size and weight. Those topics will be discussed at a later time on this thread.

   Presently I am only dealing with early-stage pueruli (which is a non-feeding phase) with a few beginning to Instar (moult) to the earliest stage algal-juveniles (first post-Instar (moult) which are about the size if a man’s knuckle. Early stage post-Instar (moult) Mandibles (baby teeth) -  Requires Strictly soft-chewable crushed-shell finely chopped diet only.

[jamesmusslewhite]

   My wife jumped in a boat before dawn, with a brand new aerator and trusty cooler, and totally hyped-up on ginseng-coffee and a grin.  Heading towards the Cabunga-an pier, to pick up the other 300 little sea-bug we ordered. And she was back home here before 10am. So you now have a reference as to how close our Dinagat Island farm is from this Island. We have another two pole-huts we maintain just outside the waters of the township of Cabunga-an. It was in those mangroves where I started raising lobsters over 11 years ago. A weekend hobby meant to remind me of fond childhood memories leading to an eleven year obsession. Winters in the duck-blinds, summers gatoring, exploding the back-washes of Inter-coastal canals. And living in pole-dwellings on tiny mud-shell islands, Jon-boats filled tackle & gear and so isolation and quite in the evenings that you swear you can actually hear the earth breath. Hot, to the knee-muggy, skeeter-infeasted, critter-ridden and full of mean varmints. Wow, that perfectly describes my life here among the mangroves of these little island’s mangroves. Well that certainly explains a lot, now I want to build me a wingless plywood wide-body Jon boat. Yep, now that is a new project for the ‘to do’ list…

   Boy did I ever get off-topic, now what was I originally intending to discuss? Oh yah my wife’s new little batch if critters. It was only yesterday that she actually was able to finally finished sewing the final net, which she would using the following morning to house these newest sea-bugs. We were actually cutting it that close. One factor which caused the fabrication of the nets, was my insistence on directly sewing sheltering to the net floorings. But researchers have come to realize the importance of providing adequate sheltering for housed stock. They tested a multitude of different materials and found that lobsters prefer what are referred to as ‘mesh bundles’.

   But researchers have come to realize the importance of providing adequate sheltering for housed stock. They tested a multitude of different materials and found that lobsters prefer what are referred to as ‘mesh bundles’. This also happens to be the ideal solution and perfect medium to construct cheap long-lasting light-weight adequate sheltering within nets.

But oddly it seems few outside of hatchery research; seem to have even heard of using ‘mesh-bundles. I guess this is because almost all the local growers primarily fix-anchor their nets directly, which is sad because they all simply discard their used finer netting material.

  By simply providing adequate ‘mesh bundle’ shelters, it would greatly help in the reduction of stress (a major benefit) as higher-stresses reduces their natural immune systems. Sufficient sheltering also help provide additional shade protection from direct sunlight (lobster by nature are naturally nocturnal) thus aiding in the reduction of stress. Shelters also help to minimizes aggression among individuals, which helps reduces major physical injuries and lost appendages. Physical injuries often result in the creation of lesions and open wounds, which can hamper properly healing; thus causing an inability of an individual to properly discard their old exoskeleton during Instar (molt). The inability to improperly instar (molt) is fatal, known as M.D.S. (Molt Death Syndrome).  Most acts of excessive-aggression and cannibalism occur during Instar (molt) cycles, sufficient sheltering can certainly help lower these instances within highly-stocked enclosures.

[jamesmusslewhite]

   When my wife got home with this last batch of sea-bugs, it led to a rather humorous situation for my wife and two helpers, who were assisting to transfer her trusty little styrofoam cooler. My wife and I took over the kayak together, because I wanted to use the underwater camera to check in and around the two nets. As the two workers (both experienced growers) cleared the cooler was completely. The empty cooler was then removed through the floor trap (a section of removal flooring) so both could inspect both inner nets. One of the guys yelled to my wife that both nets were empty, 600 pieces gone!  My wife replied impossible, dive to the bottom and check! She knew she had spent over to weeks sewing those nets, she knew every stich of all four nets, and one net just had 300 pieces added? It took her a second to process, then she started laughing. It dawned on her what I already expected, and when the two came back up to the surface they were excited and laughing at what they just witnessed. All 600 fingerlings huddled under those bow-tie shelters, all butt-first in a bow-tie and with their antenna aiming outwards. All just chilling, and content as little baby peaches. They were all merely reacting to the same natural-trigger, which was to quickly try seek shelter upon settlement. The two helpers, though each experienced net growers, had neither ever having actually seen an artificial net-shelter used before. Which I guess is my point, so little is actually shared between researchers and the common growers. In the Philippines alone now many lobsters died for the lack of a wad of discarded netting? 

   This last batch my wife just got from Dinagat Island were young, some were actually still translucent (earliest stage pueruli) meaning only weeks ago they were actually still larva. 

What are called 'phyllosoma' which resembled big flat-headed translucent long-legged space spiders rather than little baby lobsters.

This is why each of these enclosures beneath the pole-hut, actually consist of two double-net configurations. First being a larger-mesh net, this sits fix-anchored directly to the seafloor. And the second smaller fine-mesh net, which sits two feet more shallow than the first. It is in this fine-mesh net that the younger pueruli are first housed. As these pueruli successfully transition through all four pueruli developmental stages, they will then Instar (molt) to the Algal-juvenile stage.  This is when they are no longer (non-feeders) and are then vicious feeders, and must be moved down into the larger net below. This is the reason for that two foot clearance space between the two nets. This allows the larger Algal-juveniles unrestricted access to the shelters placed directly onto the seafloor area. There are two such net configurations, each designed to house 300 individuals. Individuals outgrow the larger lower level, they be moved to the nets of the floating platform.

 

[jamesmusslewhite]

     I got the final draft of the floating platform completed, and the wood needed for the framework has been ordered. Now I only have to wait for the various lengths of lumber to be milled, and then delivered to the island. Now just how long that will be is anyone's guess at this point of the game, as I would assume it is a specialty order, due the lengths, board thickness and widths. Unlike bamboo the cuts should be relatively uniform, as bamboo are stout at the trunk while steadily narrowing as the length increase.  Bamboo lengths are also rarely straight or uniform as to widths. Then as the lengths begin to dry and are exposed to the elements, elongated cracks begin to occur. When in an area with 144 inches of annual rainfall, and being so close above the water's surface, cracks quickly widen and lighten. Bamboo are chambered meaning they collect volumes of water where ever these cracks develop. One can drill holes under these cracks, but this actually weakens the overall tinsel-strength of those bamboo lengths. Our bamboo platform was really only good for a single grow-out season for a brood. This being only 12-18 being months. Now this was ideal length of time for my own research, and or building a floating platform (of they size) on a tight budget; but the platform will need to be torn-down and completely rebuilt, as it would be doubtful the structure would last half a season more without major structural-failure.

   The nets if are a decent quality, properly cleaned and maintained, than one can expect to get several full 'grow-out' seasons. Especially if these 'grow-out' are used along with sufficient sunscreen coverings. A quality agricultural  grade shade-cloth easily lasts 12-14 years of full-sun/harsh-weather usage.  This is why greenhouses, nurseries and garden-centers use them. They are extremely durable and durable against the elements. They are best used to cover the tops of the platform and along the sides of the waterline. We actually had tuna jump high enough out of the water to land on-top of our platform's decking, and once a tuna cleared the decking and our netted top-railing landing on top of our cover-net. We heard the loud sound of it flapping on the top-net, but before we could get a boat out to the platform, the top-net ripped under it's weight of a frantic flopping tuna. Then it took four lobster fishermen armed with flashlights and small nets (on a blackened cloudy night), trying to fish for a stealthy tuna, inside a floating lobster net. An odd fishing tale, but true...

      The issue is the handling and transport of lumber that length. 8(meter) long boards are just a little over 26(feet) long. And as you can see above I will need 20 that length, and that is a lot of top-heavy. My boat is a 34(footer) which means it is too short for that task. I can not lay the lumber down flat inside the boat where the weight can be evenly distributed and properly balanced, to insure the load-weight will not flip the boat in moderate-wave action. So I am looking for a 40-60(footer) wide-body boat to rent when the time does come. I am sure there are a few in and around Surigao City, merely just a minor logistic detail to sort out in advance. No biggie hah... The three diagram above I hope gives everyone a general idea as to the overall layout of the project.

Edited June 2, 2021 by jamesmusslewhite

[jamesmusslewhite]

Here are three additional diagrams of mine which I believe are worth mentioning. This first is an early diagram of the old floating bamboo platform.

it is a half-view of one of the sides of the net. What it shows is how most floating nets are designed and used, but I never felt comfortable when using a net this size. It seem to not properly distribute the weight if the net properly. What you see is three 'sag-weights to a net side, creating a cross-cross which bare the sum of the total weight of a double-layered net bottom. This means there are only three stress-points to a side of a large area. An area (space)which greatly increases weight as the housed natural bottom-dwellers increases in weight as they grow. So as the lobsters grow, coral blooms increase and algae collects to the sides and bottoms of the net; there is only an increase to the same stress-points, increasing the probable rip or tear to the netting. Which will cause a unexpected loss of housed stock, and lobsters will quickly exploit a sizable rip or tear. A lobster farmer's worse nightmare lost waiting to happen, the 'Great Escape' of most if not all of your housed stock within mere hours.

   Once I realized the builtin flaw to this setup, I immediately relocated all my stock and started thoroughly cleaning the nets. And I totally resigned my net configuration. 

   First designed a new outer net system, I jokingly refer to it as a cross between a 'support-sock and a bra', as those are the primary fictions it accomplished. First instead of only having three heavy sag-weights to a net's side, the system changes it to 5 lighter sag-weights. So the overall stress-points are increased from 8 primary stress-points to 16 stress-points. And where the net bottom was a criss-cross configuration distributing the net bottom over 4 areas, the new configuration distributes that same weight over 16 floor areas. So the inner-connecting tied knotted roping system, allows a better weight-distribution throughout the sides and the bottom of the net.

   The sock-configuration adds an additional net-layer to the sides and the bottom of the first net. Making it two layers on each side, and three layers on the bottom of the net, which greatly increasing the overall strength and durability of the net enclosure. Now this 3rd diagram is of a side addition that easily attaches to the floating platform once completed.

  This diagram is a multipurpose add-on to the floating platform. It can be used as a work area, storage shed or a security-hut. Will have solar, camp-burners, WIFI, compost-toilet and comfortably sleep 1-2 individuals. Has PVC net enclosure built directly underneath it's frame. More than one of these can be easily pulled up next to the floating platform and attached. As I enjoy night-fishing, shrimping and crabbing; and having a floating lobster platform mere meters off-shore from my front-gate, is why I designed this little toy box for myself and the wife.

 

 

[Old55]

James, do you have anything to share more inline with what would affect other Expats or visitors to Philippines? 

What you have accomplished with the lobsters business is nice but it's the only thing you post. 

[jamesmusslewhite]

12 hours ago, Old55 said:

James, do you have anything to share more inline with what would affect other Expats or visitors to Philippines? 

What you have accomplished with the lobsters business is nice but it's the only thing you post.

 

   So why do I seem to primarily focusing on only mariculture topics that no other expat or visitor to the Philippines, would possibly find interesting or noteworthy? Well that answer must be quite obvious. Either I must be incredible stupid, or a shameless narcissistic self-promoter...

   I guess the truth is perhaps hidden somewhere in the middle of those two options. I came to the realization long ago that lobster aquaculture is Philippine-wide industry which has a 5% annual growth. Here in the Caraga Region of Mindanao alone, Aquaculture generates over 112 million (metric tons) annually. If using a calculator to multiply 112 million (metric tons) by only 90php per kilogram, that is a bunch of little zeros. Then when concerning that the Philippines actually has 7,641 islands according to the Secretary of the Department of Environment and Natural Resources (DENR), and each island is encircled by saltwater ecosystems. and as the Philippines is actually 5th in the world with km/36,289 of shoreline, (Australia is only 8th) and there are approximately 256,185 hectares mangroves scattered around these islands I can not shake the silly notion that others, are looking for ways of profitable ventures on a reasonable shoestring budget. I have never hidden the fact that the wife and I live on a modest $900 monthly budget. But you may be right just the same.

   We manage to eat well, and live simple. We managed to build a small simple resort on the island, where the locals come to swim with small open bungalows we rent by the day. Certainly nothing fancy by any standard, and try to avoid showing it on the forum. Doing so could rightfully be interpreted as promotion by some forums. Sticky subject. As I don't live in a city, rarely venture away from this island. Last dated when Marcos was still Chief, and happy married 34 years, Brought her to the US on a Fiance Visa and married her there. Purchased our farm years before we both retired and moved here in 2008. I have not even visited our farm in the last three years. We have lived on this island for almost six years. So I am rather limited as to things expats and visitors are interested in. Never seen dating apps, girly-bars, cheating wives and girlfriends and other nonsense that fills all the Expat forums. The only advice to others is stay away and keep your nonsense and drama to yourselves. So that sort of limits possible thread topics I might be able to contribute, especially when there are often times I do not even login to forums for weeks or even months. This is the first thread I started this year. The last thread I had open before that, was internet related, and I last posted in that one was sometime back in late December. The last mariculture related thread was about the previous floating bamboo platform, I believe I last posted in that one sometime in December of 2019 (a year and a half ago).

[Dave Hounddriver]

Thanks James.  Nice to hear a little bit about you and what you are doing over there.  You are correct about the fine line between self promotion and chatting with us to inform members what you are up to and what can be accomplished in Paradise Philippines.

Your latest post is very informative and personal.  Many readers will enjoy it.

[Old55]

I also thank you for sharing a bit about yourself James. We know each other from another forum many years ago so I know you have much to offer here.

Clearly the lobster farming is an important passion and a successful business for you.