What is a sustainable fishery?

Question

any and all info about sustainable fisheries, how does it work?

Answer 1

One where the number of fish taken are no more than the number added to the population each year.  Where no damage is done to the environment in the course of fishing.  Where the fish caught are not from the prime breeding stock.

Answer 2

the two people above have given you sustainable fishery .the bigger holes and not over fishing mainly applies to the sea,and it is only sustainable if everybody does it ,and how does one controll that,

Sustainability means that it does not deteriorate with time maybe even gets better.

This is about self sustaining fish ponds which can be under control, self sustaining meaning that the food production is also included in the production.

.maybe not exactly what you asked

PERMACULTURE ANSWER

AQUACULTURE and fish food

This starts with the design of the pond already .

PONDS made with cement

Dig a shallow basin ,with a deep hole in the middle,using all the soil on the surrounding edge (most of it going on the down side )

connect some water flow ditches.with a way out on the side (where the ground is hard )as an overflow.

line it with rocks and let it lie for a while so that it gets rained upon and the ground gets compacted,

spread concrete over it and then fine cement, as a finish paint it with cement ,

if you use paint afterwards be careful,many paints are toxic to fish.

DESIGN

if made from cement stepped down with sloping walls like an inverted pyramid is the easiest to do and straight walls do not accumulate anything which falls down, to cause something to grow or become food .

All of the surfaces of the dams sides and bottom should be productive to ensure maximum opportunity, and maximum utilization of space ,there should be life everywhere.

AQUA CULTURE IS A CUBIC CONCEPT so we must think of utilizing the cubic space to the maximum

And also utilize the EDGE EFFECT so on the water side of the edge In the shallows,

The edge of the dam should be serrated or undulating to double the edge distance .

This is the most creative space and it's where all the small fry hang out ,the water is heavy with gas from the decomposition of dead plants at the edges.

Very warm because it is very shallow ,from nothing to a foot. Minimum a meter or so wide , the more the better depending on the size of the dam.

Big fish cannot breathe here and it is a safe place for the young, because of the environmental difference .

Here are the aquatic plants that grow in shallow water such as watercress ,Gravel on the floor for nursery beds .In el Eden(my garden in Mexico) the first level was also lined with roof tiles ,the hollow parts facing down creating hiding places for the shrimp.

The next level down

from couple of feet to a 1.5 meter the water is cooler the plants are taller and rocks on the bottom are bigger ,

Here the reeds are planted . In small cement ponds ,pots can hold reeds (for a while)

.Objects below the surface can grow food ,if the light reaches .The stems of reeds, ropes , bones ,rocks , grow algae for the fish to suck . I liked using skulls of cows because it looks nice and they have large surfaces

In the depths or in the middle

This can be as deep as the size of the dam allows a pointed cone or pyramid has a limit where it comes to a point depending on the size of the pond.

Here is the coolest of all ,everything big lives here .Because of the different levels of water there are different temperatures and this alone creates currants.

Large pots , cement or pottery pipes, reed cages provide romantic places for fish. Large rocks hide prawns.

Now flora on the water surface itself

Have plants that float .Lellies .Lotus duck weed etc(depending your climate),these are feeding places for fish and shrimp .

If invasive ,plants such as water hyacinth ,can be corralled with logs or bamboo .When abundant , and used for a rich mulch or feed cattle, deer, elephants, horses etc.

Encourage duckweed, a rich source food for a variety of pond life ,this does well with a lot of sun .And it shades the water. Shaded places apart from being cooler also hide the fish from outside predators such as birds .

Make islands for water fowl to provide safe places for their eggs and ensure that their droppings are utilized as fish food in the water.

On water side of the edge,

is the best place to plant anything,like water chestnut water cress ,water blommetje,reeds ,papyrus, ground rooting lilies like lotus etc.

Shallow rooting plants near the edge and bigger things with deeper roots systems and bigger branches , further away .

Surrounding ,the dam with a variety of food producing factors, such as chicken or pig houses ; designed so that the manure drops into the water.

German bass as can be expected love cow manure

Droppings ,like seeds or dead material ,from edge plants and trees are further sources of food for life within the pond.

Elephant ear plants ,quickly turn yellow and become soft when they hang in the water ,and are then eaten by the fish .and a lot of water plants have this same effect

There are other plants that hang in the water and do not change ,so rule these out.

From the sky

The sun makes almost every thing grow ,water cover plants ,algae on the rocks ,edge plants ,the lot and one has to be ruthless, with trees and their crowns , to make sure that the light reaches. so be strict with cutting back branches if their shadows dominate the dams surface.

Have the element reach the pond or dam such as the Sun,the Stars and the wind as well as rain water flow going in ,because a pond is a receptive sensitive organ which absorbs, sound, heat ,cold, cosmic forces ,gathers dusts ,consumes any thing small that falls in.

The effects of anything touching it is transmitted throughout , because of the wave motions created. .Whether it be active such as the wake of a boat or the ripples of a stone thrown in .whose resulting waves will reach all corners .

Or passive like a branch hanging in the water or rock, and the water movements resulting currents will reach all depths.

The effect of night and day alone causes the water to be in constant motion .

A pond is a trap for insects that are blown in or fall in or are snapped up by hunting fish as they cruise the water.

A ponds surface can be likened to something like an ear, eye, mouth, stomach all at the same time.

I believe the whole pond knows your there if your reflection is in the water ,at whatever angle .Long before you can see yourself.I have had this proved to me countless times by seeing the reactions of the fish,and so by keeping your reflection out of the dam you will see much more fish by peeking over the edge.

Extreme caution with throwing in large quantities of food in small ponds, one banana is O.K. but a bunch turns the water milky .and within hours the biggest fish are floating belly up .

In el Eden ( in Mexico) all the big tilapias died in one day , over 60 of them, in fermenting water ,because of the many tortillas that were throw in by Fish lovers anxious to please

STOCKING THE POND

always stock a polyculture to make sure the wastes of one specie does not contaminate the pond

So stock your ponds with a variety of fish, and aquatic plants ,this ensures healthy water

Fish with mouths on top at the surface, mouths in front in the center ,mouths facing the bottom on the floor not only fish but a variety of life.

Anything local one can get hold of, shrimp and aquatic plants ,maybe not everything together.and keep an eye on the ratio

Turtles for example eat the plants and crocodiles eat the fish ,they are only suitable in large dams and not too many,

The greater the variety ,the less problems .Such as contamination . Or to acquire food some of it being the wastes of other species.

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EARTH DAMS

in natural places that lend them selves to be utilized for a dam

TURKEY NEST

A turkey nest dam is on the flat it has a raised edge or even edge all around with some furrows or a creek feeding it and harvesting rain water.

And a large pipe is the best way to have an overflow or out let ,or better several to go into different directions to connect to other dams or irrigation systems.

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HORSE SHOE

A horse shoe dam is on a slope ,the walls form a horse shoe shape,leaving the ground flat on the top side for incoming rain water .and the overflow should always be near the top on the original hard ground to safe guard the wall .

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SADDLE DAM

This is the highest type of a dam on a neck or plateau ,in between mountain tops catching rain water from the peaks ,this type of dam will give the most pressure and tends to be the cleanest so is recommended for drinking water

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As a conclusion there are many ways to produce fish food ,apart from the chicken,pig,cow and duck manures,And the vegetable substances like plants wastes and duck weed-

We can for example breed invertebrates .

TERMITES in a half buried barrel with holes punched into it,filled with rotten pieces of logs and paper and a sprinkler on top

GRASSHOPPERS,in half a barrel laid hollow side down.painted yellow or a plastic tent of the same shape and color.

ANTS,piles of bones

COCKROACHES,and spiders ,in a pile of thick mulch,which will also develop worms.

Answer 3

Look it up!

http://en.wikipedia.org/wiki/Fishery

Answer 4

It revolves around the concept of sustainibility which is to use something to an extent, but not over-use it, and to keep it going.

With fishing, it's dangerous to overfish because it can upset a whole eco-system so now governments are trying to impose plans to keep it sustainable.

For example this is like keeping the holes in fishing nets a certain size so only larger fish are caught (so younger fish under breeding age are not killed before they can reprofuce)

It also means imposing laws disallowing fishermen to take too much fish over a certain period of time.

:)

Hope i helped a little :)

xxxx