Farming Fish in Open Ponds


(lively music) – [Voiceover] Increasingly, the fish that
consumers buy begin life in hatcheries, and are reared in
ponds such as this one. Throughout the Eastern seaboard, a new industry has been developing, aquaculture, the raising of fish under managed conditions whether in net pens, cages, tanks, or open ponds. Private growers and government agencies have been raising trout for food and to stock streams and lakes for over a century. More recently, farmers have been intensively rearing species such as striped bass, salmon, sturgeon, and catfish for markets
that once depended solely on harvests of public waters. With appetites for fish on the rise, and harvests of natural stocks near their
limits, or in decline, fish farming holds promise for satisfying
the growing desire for seafood. But bringing fish profitably to market doesn’t just happen. – It’s a very interesting business. We learn something new everyday. It takes a lot of hard work, a lot of manpower at times, and we have to put a lot of hours in here. – [Voiceover] Farming fish calls for no less
a commitment than farming the land in time, in management, and in capital investment. Is it for you? – That’ll make them just under two acre ponds. – That’s right. – [Voiceover] It begins even before you dig
or adapt an existing pond. It takes a business plan that outlines your
objectives and your means for attaining them. And it
takes an attention to details. From making sure your pond is adequately prepared to properly stocking fish, to staying on top of water quality, to providing nutritious feeds. And finally, after harvesting, to packing
your fish so they remain fresh. Whether you choose to raise newly hatched
fish called larvae or fry, to the fingerling stage — a period
of some one to two months, or begin with older fish, two-month old fingerlings or larger year-old yearlings, your first concern will be to ready your pond for receiving them. Pond preparations are especially important
for raising striped bass fry through the fingerling stage. Unlike newly
hatched catfish and trout, striped bass fry generally
don’t begin feeding on pelleted food. Rather, they are usually reared over the first
month or two on a diet of zooplankton. Zooplankton is a
general name for tiny animals that grow at different rates and to different sizes. They are the key to
survival of striped bass fry providing the growing fish with essential
nourishment. In successfully growing fry to the fingerling stage, ponds must be managed to promote an abundance of zooplankton. Even if you don’t raise fry, but begin with
fingerlings, it is important to know about the operation
you buy your fish from. The more you know, the better you’ll be able to assess their quality. Let’s consider pond preparations for raising
striped bass fry. These preparations will begin months before you have the newly hatched fry delivered from the hatchery. To begin with, you’ll want to drain your pond and let it dry out. A dry pond will promote
soil aeration and help control the growth of nuisance aquatic vegetation. Note the construction of the pond. There are no obstructions. The pond bottom is smooth and cleared of debris. This will facilitate harvesting and protect
against the tearing of seine nets. Ponds may need to be limed periodically to
stabilize the soil pH and to improve alkalinity or water hardness. Because large numbers of zooplankton require a lush growth of algae, managing algae blooms is critical to successfully bringing striped bass fry to the fingerling stage. Such efforts largely depend on applying fertilizers, monitoring water quality, and taking quick action such as adding oxygen to the pond if oxygen levels in the water begin to drop. There are a variety of organic fertilizers such as cottonseed, soybean meal, hay, or
animal manures. These organic fertilizers act as a time-release supplier of inorganic nutrients that algae require for growth. Care must be taken in choosing and applying fertilizers. Too much decomposing organic fertilizer can cause rapid losses of dissolved oxygen. Before filling, the pond drain is sealed. It is important that dirt and debris are cleared or else the pond will leak. In this pond, blocks of wood are lowered to close the drainage hole. A screen is placed in front of the blocks to protect against the loss of young fish
when pond water is lowered for harvesting. If your pond is fed by surface water, you need a filter such as a fine mesh sock
over the inlet to prevent predators and unwanted fish from entering the pond. Mesh openings come in different sizes. The smaller the mesh size, the more effective protection it affords; however, a smaller mesh is likely to clog
more quickly and need regular cleaning. (light music) Fly ash or sawdust is used here to seal spaces in the wood and prevent water from seeping through. Because algae blooms and zooplankton populations need time to get established, it could be several weeks before you can stock the pond with striped bass fry. One way to keep track of a developing algae bloom is to take water clarity measurements with
a Secchi disk. A shiny plate, the Secchi disk is lowered into the water to measure how far down you can see. The greater the abundance of algae, the shorter the depth at which the disk is visible. – Secchi depth, 70 centimeters. – [Voiceover] Ideally, the disk should disappear from view between 15 and 20 inches. Daily measurements of water clarity will give you strong indications of how algae blooms are developing. Spring-fed ponds, unlike those fed by surface water, do not have natural zooplankton populations. Consequently, you will need to inoculate the pond with zooplankton. It could take a couple of weeks for a succession of these populations to develop. Ideally, to ensure that they are developing adequately, you’ll need to take periodic samples. One simple method for capturing zooplankton is to pull a zooplankton net through the pond. Under a microscope, the animals can be examined to make sure there are sufficient numbers and diversity. Once again, these actions are for growing striped bass
fry to the fingerling stage. Catfish fry, for example, or tilapia and trout fry can be grown on prepared feeds right from the beginning. Just as for striped bass beyond the fingerling stage, zooplankton production for these species is not critical. The numbers of fish you stock per acre will depend on the species and size you start with, and the stage you plan to harvest. At all life stages, fish are sensitive to handling and other stresses, in particular changes in temperature, dissolved oxygen levels, pH, salinity, and alkalinity. This is especially
so for striped bass fry where the newly hatched fish are packaged
for shipment. With proper packing, fry can be safely shipped long distances. It is best to stock fish at night away from
sunlight so that they are not subjected to bright light and extreme thermal changes. – [Man in striped shirt] All right, let’s
get the fish. But don’t mind the pine trees. – [Voiceover] Because water quality and temperatur may differ between the hatchery you purchase fish from and your pond, the fry will need to be acclimated to their new habitat. This will minimize shock and the possible
onset of diseases. – [Man in stripes] Well, need to make sure
the temperature is close to the same within a couple degrees of each other. – [Voiceover] First, float the shipping container that the fry are delivered in. This will help to gradually equalize temperature between the water fry
have been shipped in and the receiving water. Once temperatures
have equalized, gradually exchange water by cutting the bag and slowly adding water to it. – [Voiceover] Feels like it’s right about 70 degrees. Let’s just go ahead and release
them. I got it. Turn ’em loose. We check survival in these
ponds. Last night we went ahead and stocked ’em. – [Voiceover] Periodically, you must check
the survival and growth rates of the fry. You can do this by dragging a
tow net, or Seining, or even shining a flashlight in the pond at night. If there’s a problem, first check if the zooplankton population
is adequate. You will also need to check water quality conditions. Failure could have a number of explanations. For example, it may be because of insect predation or inadequate numbers of zooplankton. In such events, you may have to drain the
pond and begin again. When striped bass reach fingerling size after one or two months, they will be harvested and in some operations brought back to the hatchery. Growers new
to fish farming will often begin with fingerlings because mortalities are likely
to be lower than when in raising fry. Once again, this is why it is important to know about
the operation you buy your fingerlings from. It will better enable you to judge the quality
of your fish. All fish species should be graded by size.
This can prevent larger fish from eating smaller ones. In addition, larger fish can be fed bigger, less expensive feeds. After grading, fish are weighted so that they can be fed
the proper amount. The amount of feed is based on a percentage of body weight. – 950. – Okay, take them back to Neil. – [Voiceover] It is in the hatchery, generally, that striped bass fingerlings learn to accept
pelleted food. Once the new fingerlings begin to feed regularly, they’re ready for shipment or transfer to
ponds where they will be grown through the first
season. – 95. 98. – [Voiceover] If you want to grow large number of fish, then you can stock at high densities though the final stage will be small. – 147. – [Voiceover] If you want to bring fingerlings
to the quarter-pound size, then you’ll need to stock at lower densities. – Some of the mistakes you can make in fish farming is not pumping water, overstocking your fish, and what I mean by that is like if you had
a acre pond, you put six to seven thousand fish, you’ve
overstocked it. You wanna put anywhere like 3,000 to 400 for just an example. A lot of people just think that you can throw
fish into a pond, but that’s not the answer. – [Voiceover] Your decisions on how many fish per acre to stock, will again depend on your goals, on survival
rates, and on your facility and equipment. – Once we determine the number of fish in
the pond when we take our samples, we feed them based on the total body weight of fish in the pond. That’s different percentages are determined by the size of the fish. For instance, the smaller fish gets a high
percentage of feed than a larger fish. – In ponds, smaller fish are fed approximately 20% of their body weight daily. As time goes on and the fish get larger, their percentage drops to about 3 percent
of the body weight depending on the species, temperature, and the size of the fish. As the fish get larger, the pellet size increases and the nutritional value also changes so it’s adjusted for larger fish. It’s important to get a good true sample size of the average body weight. While it’s easy to hook and line fish, and
a lot of fun, it often gives you the largest, most aggressive fish. You can sample in several ways. At feed time, you can use a Seine net, a dip
net, or a cast net to get a good average sample
size. – We’ve already weighted the water. – [Voiceover] What and how you feed will depend on several considerations; the number of ponds you have, their size,
your investment capital, and your time. Some growers like Al Watson who has seven one acres catfish ponds, feed by hand. Others use blowers or timer-activated feeders, or demand feeders. On this nine-acre pond,
Walter Bowling has feed cast from a small outboard to satisfy some 40,000 hungry mouths. You may begin with the heartiest fry or the
healthiest juveniles, or the strongest yearlings, but unless you
manage your systems so that fish are reared in optimum conditions of water quality, you’re lowering chances for success. – That’s your best sales product that you
can have is high-quality fish. Sales and water quality are one on one. The better the water quality, the better your
prospects of high quality fish. – [Voiceover] The most common results of poor water quality, if not immediate death, are disease outbreaks
and slower growth of fish. This means you must monitor dissolved oxygen levels regularly. – We’ve been all right up to this point, but
you gotta keep check on it, you know? If we don’t, we could get in trouble. – [Voiceover] It means you must take regular measuresof pH, temperature, ammonia and alkalinity, or water hardness
so that you can take actions at the first sign of a problem. Measure oxygen and temperature daily at the surface and bottom to detect if your pond is stratified. Temperature should be measured daily for information used in feeding levels. Warm water also holds less oxygen than cold water. So it is particularly important during the
warm months, that you watch oxygen levels carefully. – Oxygen concentration should be taken near the surface, near the midpoint of the pond as well as near the bottom to make sure that there’s not stratification
occurring. – [Voiceover] Before oxygen levels drop below 3 parts per million, you should begin adding oxygen to the water by aeration. You can do this by pumping in fresh water,
or by employing mechanical aerators. Because well water or spring water contains little or no oxygen, aerators may be needed to raise oxygen levels to an acceptable range. pH should be measured at least once a week if not more often. If pH values are outside the range of 6.5
and 9.5, you’ll have to take steps to restore the desired levels. Since algae in the pond can affect the pH,
take your measurements at the same time of day to compare results. Liming the pond may stabilize the pH level, thereby minimizing the effects of the algae. There are other considerations that must be taken into account from handling fish over the winter in ponds that
freeze to responding to problems of fish disease. Even the most effective quality control, and
most attentive management may have to deal with outbreaks of parasites, or bacterial and viral diseases. You must plan for the unexpected, and be ready to respond immediately. When you prepare to harvest a pond, you must be prepared as well to handle the fish quickly and efficiently. You must know your market beforehand. In general, in ponds, it takes a year and
a half to two years to raise fish from fry to market size. This is a rule
of thumb. – 14 fish, 13 pounds, 13 ounces. The actual
growth to market size will depend on the quality of the fry. Again, that’s why it is important to know
your seller. Growth will also depend on feeding both the quantity and quality of the food you provide your fish, and it will depend on the water quality of your pond. If you’re selling to buyers, for
example, who are going to stock their own ponds for
grow out, or for recreational use, they’ll need to have aerated tanks to ensure
the fish they buy from you will be healthy when they’re unloaded in their new pond. – As far as packing, the way I like to pack
my fish, I like to wash my fish off. I chill my water with ice. It’d make the fish nice and a firm fish as
possible, I run it up on top a conveyor system onto a table which I like to take my fish
and sample them and weigh them to see what the average weight which is very important ’cause I like to have a certain count of my
fish boxes which is very important ’cause the market much like a pound and a half fish to a two pounder, well, your count’s very important to this. Another secret is having the right type of
ice to pack your fish. I like a flake ice, a very light ice which
has a real cold temperature to it. I’m putting the proper poundage of ice. It’s very important because when this fish
leaves its farm I want it to be a fresh product,
and it’s gonna be a nice firm fish. If it has to be shipped three to four hundred
miles, they’ll last three to four days. – [Voiceover] The trend in the United States
has been a rising consumer demand for fish. The opportunities for satisfying that market and for making profits can increase. Whether they will or not depends on you.

local_offerevent_note November 10, 2019

account_box Gilbert Heid


local_offer

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