INTRODUCTION TO FISHERY [FISHERY]

 

CHAPTER ONE

INTRODUCTION TO FISHERIES

 

Fishery is an aspect of fish production such as fish culture, processing, marketing and distribution of fishery organisms.

Fisheries refers to all activities relating to the act or business  of  fishing, culturing, processing, preserving, transporting, marketing, distributing, developing, conserving and managing aquatic resources and the fishery areas, including the privilege to fish or take aquatic resources  thereof.

Sub-divisions of fishery

There are three ways in which fishery are sub-divided:

i. Capture        ii. Culture        iii. Industrial

CAPTURE FISHERY- This is an exploitation of aquatic organisms without stocking the seed. Recruitment of the species occur naturally. This is carried out in the river, reservoirs, sea, stream etc. Problems associated with capture fisheries are overfishing and pollution.

Methods in capture fisheries

i. hook and line           ii. Cast netting/ drag netting   iii. gill/set netting        iv. Trapping     v. trawling

vi. spearing/ harpooning          vii. Purse seining/ seining

CULTURE FISHERY- This is the cultivation of the selected fishes in confined areas with utmost care to get maximum yield. The seed is stocked, nursed and reared in confined waters, then the crop is harvested. Culture takes place in ponds, which are fertilized and supplementary feed are provided to fish to get maximum yield. Culture fisheries is conducted in freshwater, water and sea water.

Facilities for rearing fish

i. earth pond    ii. Concrete tanks        iii. plastic tank             iv. Fibre glass tank      v. wooden tanks

vi. tarpaulin tanks        vii. Fish pen     viii. Fish cage/ happa.

INDUSTRIAL FISHERY- This is the activity of catching fish and other seafood for commercial profit, mostly from wild fisheries. It is also known as large-scale commercial fishing.

TERMINOLOGY USED IN FISHERIES

GEAR: The instruments used by fishermen when fishing e.g nets, traps, hook etc.

FRIES: They are the newly hatched fish. It is the development stage immediately after the larvae stage.

FINGERLINGS: These are fish that has developed into a length of finger after hatching and has a fingerlike structure.

SHOOTERS: These are fish that pass fingerling stage but has not reached juvenile stage.

JUVENILE: These are matured fish but have not reach or developed into a marketable size.

TABLE SIZE: These are matured fish that have reached marketable size i.e fish that are sold to customers for consumption.

 

 

1.1                                                       AQUARICULTURE

 

Aquariculture is the cultivation of selected fishes in a confined area with utmost care to get the maximum yield.

TYPES OF AQUARICULTURE

There are three types of aquariculture. Viz:

1. Intensive system     2. Semi-intensive system         3. Extensive system

CHARACTERISTICS OF INTENSIVE SYSTEM

I. High stock density  II. Feeding of fish with complete diet                        III. High production cost

IV. High use of technology    V. Very high yield      VI. Short production period

CHARACTERISTICS OF SEMI-INTENSIVE SYSTEM

I. Moderate stocking rate        II. Use of supplementary feeding       III. Pond fertilization is done IV. Occasional flushing of pond water           V. Moderate production cost            

VI. Moderate or low level of technology       VII. Yield is moderate.

CHARACTERISTICS OF EXTENSIVE SYSTEM

I. Simplest method of fish culture      II. Low stocking rate  III. Little or no use of fertilization

IV. Little or no use of supplementary feed/ fish depend on natural food.

V. Relatively low level of technology especially during harvesting.  VI. Low input

VII. Low yield/ output.          VIII. Low production cost.    IX. Long production period.

ADVANTAGES OF AQUARICULTURE

1.  To produce seed for culture.

2.  Availability of fish all time.

3.  It provides an efficient means of protein production

4.  Sources of income and employment.

5.  Providing a consistent supply of fish for food.

DISADVANTAGES OF AQUARICULTURE

1.  Large amount of feed is required to grow fish.

2.  Small spaces leads to fin and tail being damaged due to rubber with nets or wall of hatcheries.

3.  Water pollution as a result of overcrowding of fish.

 

 

 

1.2                                                       FISH FARMING

        Fish farming refers to the rearing of water dwelling organisms in controlled or semi-controlled environment to enhance productivity. It is also used to refer to Aquaculture, pond culture and mariculture (fish farming in sea water)

The organisms are farmer or grown because they have value to man. These organisms include fishes, mollusks crustaceans aquatic plant etc.

A BRIEF HISTORY OF FISH FARMING IN NIGERIA.

Fish farming is seen as one of the most lucrative aspects of Nigeria’s agricultural sector. Fish farming  in Nigeria can be traced to the effort of the colonial administration in early 1940s when they began to play closer attention to the colony’s local resources, which included fisheries during world war II. The government established a fisheries organization in Lagos. In 1941 the preliminary survey and experiments were conducted in the ponds, lakes and lagoon of the area.

In 1945, the organization became a section of the department of commerce and industries. By the 1950’s, the organization had grown to become the federal fisheries services. 1954, the operations of the branch were split between the federal and regional (Northern, Western and Eastern) governments. After the nationwide campaign of GROW YOUR OWN FISH in 1964 there have been an increase in the number of fish farming in Nigeria. In 1975, Research institutes were created out of the federal ministry of fisheries e.g Nigeria institutes of oceanography and marine (NIOMR), Federal department of fisheries (FDF) etc

Presently fish farming as been one of the lucrative industries in Nigeria with catfish, prawn, tilapia, carps being some of the more popular fish. The federal government has made some efforts in august 2013, to boost aquaculture performance in the country, the minister of agriculture and rural development. Dr. Akinwunmi  Adesina inaugurated the special Growth enhancement support  scheme (GES) for fisheries and aquaculture value chain in Ado-Ekiti, Ekiti State, which leads to distribution of 500 juveniles state and five bags of feed (at 50%discount) to 840 fish farmers in 10 states along with 200 water testing kit.         

IMPORTANCE OF FISH FARMING TO MANKIND

1.         Fish farming serves as a source of employment

2.         It prevent over fishing since fishes continue to reproduce

3.         It help in the reduction of the extinct of species of fish or other creatures.

4.         Fish farming allow better use of wet land

5.         Source of income to farmers and revenue to governments

6.         Contributes to National food security

1.3       PROBLEM OR CHALLENGES OF FISH FARMING IN NIGERIA

There are numerous problems faced by fish farmers in Nigeria.

1. LACK OF FOOD SOURCES: Despite the production of about 3.8 million tons of animal feed each year in Nigeria, of which 68% are poultry feed, 28% is pig feed only 35570 tons, less than 1% of the all animal feed. The phenomenon of unreasonable feed ingredient ratio is more common. Except some imported feed, the most feed compost by only beans and grains, while the fish feed pellet, which can promote the development of aquaculture, is blank in Nigeria. Most catfish farm mainly feed rice bran and wheat bran, a few farms add about 5% of the fish meal. Because the unreasonable nutrient composition, the feed conversion rate is low, breeding cycle greatly extended, objectively, increase the waste of food, induce the production cost, reduce the production efficiency of the farm.

2. LACK OF LARGE-SCALE FRY PRODUCTION(FISH SEED): The fish hatchery in Nigeria in far from meeting the need whether quality or quantity. Take the Southern, Edo state as an example, a total of two hatcheries, no more than 200 thousand tails, to supply the fish-fry market in the 5/6 surrounding state which leads to the catfish fry being in short supply.

            The north fry supply is mainly in Plateau and Kaduna, the south is mainly concentrated in the Enugu and Ibadan, because of rare fish hatchery. Each newly hatched catfish seedling cost 10 naira, after cultivation for a week, costing 20 naira more expensive for larger size. Tight amount of fry seriously hindered the development of aquariculture.

3. LACK OF NECESSARY EQUIPMENTS: It is difficult to get the equipment and materials that can boost development of the Nigeria fishery these materials include fishing nets, fish feed processing equipments, fish processing machinery etc. Some advanced technologies cannot be fully utilized without the necessary equipment support.

4. LACK OF MEDICINE SUPPLY: Because of the hot climate in Nigeria, serious fish disease cause relatively large loses. The antibiotics used are relatively scarce by the shortage of fish medicine, the price is so high, it is difficult for farmers to accept, rare farmers take preventive measures, the aquaculture stay backwardly depending on the weather, once the fish diseases outbreak will cause great loss.

5. POOR RECORD KEEPING: This is one of the challenges most fish farmers in Nigeria face. The problem hinders the sustainability of their fish farming businesses. For every business to be successful, proper tracking of the record is important.

6. PREDATORS: Most fish farmers face the challenge of their fish being eaten by some animals e.g eagle, snake, frogs, toad etc.

7. FLOODING: Since major fish farmers rely on pond for the activity, some of them are constructed so close to water channels hence leading to loss of investments to flash floods.

8. LIMITED ACCESS TO LOAN: In spite of various governments interventions to develop the agricultural sector of the economy, access to Agric loan is still very limited. In fact, most of the loan meant for Agricultural development are either diverted or given to office farmers who spend the money on things other than Agriculture. Many that really want to invest on fish farming cannot obtain loan due to stringent requirements by banks and other financial institutions.

 

1.4                                      FISH IDENTIFICATION

                                       STRUCTURE OF FISH

                           

                                CHARACTERISTICS OF A FISH

1.         Fish are mostly ectothermic (cold blooded animal)

2.         They have gill slits which they use to breathe by drawing out oxygen from the water around them.

3.         All fish are vertebrates

4.         Most are covered in scales while same can be covered in skin.

5.         Their limbs end in fins and not digit. Although same fishes do not actually have any limbs.

6.         Their skeletons are either made of cartilage or bones.

7.         Some has barbells or fleshy feelers (whiskers) like catfish

8.         Some fish have spines (catfish) while other species have no spines.

 

                                                        TYPES OF FISHES

                                               (Based on their habitat)

        There are two major types of fish based on their habitat. These are:-

1.         Fresh water fishes:-These are a fish that lives in water that has no salty taste-streams, springs, rivers, ponds and lakes. The fresh water fishes include trouts, pike, carp, perch and mudfish.

2.     Salt water fishes (marine water or brackish water):-These are fishes that live in water that has salty taste such as the seas and oceans. Many fishes including salmons, mackerels, tunals, catfish etc.

(Based on their morphology of the fishbone)

1.     Bony fish (osteichythyes):-These are those that possess bony skeleton or what is termed hard bone. Fishes that belong to this species are spindle shaped ova in section and flattened. Skin is protected by protective scales. Some fishes of the category have actual lungs to breathe and also have sharp eye sight. These bony fishes have a gas filled chamber called airbladder house under the skeleton to allow them to remain buoyant. Another adaption is operculum a bone on the side of the fish to protect the chamber that house the gills.

                    Bony fish are again classified into ray finned and lobe finned fish. Ray finned fish have thin, flexible skeleton rays. Lobe finned fish have muscular fins supported by bones. Example are tilapia mudfish carp etc. majorly found in fresh water, salmon, eels, carp found in marine habitat

                                            CHARACTERISTIC OF BONY FISH

a.          Have more or less bony skeleton and numerous vertebras

b.         Mucous glands and embedded dermal scale are present in the skin.

c.          Have paired fins.

d.         Jaws are present.

e.          Gill arches support the gills and are protected by the operculum.

2.     CARTILAGINOUS FISHES {CHRONDRICHTHYES}:- These are those that possess soft bones or bones compose of cartilage. Only the teeth of this species and rarely they vertebrae are calcified. Majority are found in the sea (salt) water. Examples include sharks, skates, dolphin and rays.

 

 

CLASSIFICATION OF FISHES

        Fish are broadly classified into two. These include:-

    1.     Finfish      ii. Shellfish 

FINFISH

 Finfish are divided into two, namely:

i.                    White fish

ii.                  Oil –rich fish.

 

WHITE FISH: - These are sometimes referred to as “lean fish” because all the oils are contained in the liver, which is removed during gutting. White fish are further sub-divided into three;

1.        Round white fish:-Examples include God, hake, Pollock, haddock etc.

2.         Flat white fish: - Example includes Brill, turbots, Plaices, Lemon sole, Black sole.

3.         Cartilaginous fish: - Example is ray, shark, and rock, salmon.

OIL-RICH FISH: - These are fishes that oils are distributed throughout the flesh of the fish. e.g. sardine, trout, mackerel, herring, salmon are common example. Occasionally, you will find fish classified in a different way. Demersal and pelagic fish. Demersal fish are those which live on or near the sea bed. Round and flat white fish fall into this category. Pelagic fish swim in mid-water on near the surface oil-rich fish such as tuna, mackerel, herring are common examples.

SHELL FISH

 Shell fish are broadly divided into two main categories.

a.       Molluscs

b.      crustacean.

Molluscs : These are sub-divided into three

UNI-VALVE MOLLUSCS :-They are those shell fish with one shell e.g. periwinkles

BI-VALVE MOLLUSCS:-are those with two shells hinged at one end. Example is mussels, oysters and scallops.

CEPHALOPODS: - This type of shellfish has no outershell, but just a single internal one called a pen. Example include squid and cuttlefish

CRUSTACEANS: - These are more mobile creatures with hard segmented shell and flexible joints. Examples include prawns, shrimps, crab and lobsters

 

 

NAME OF COMMON FISHES IN THE MARKET

COMMON NAME	SCIENTIFIC NAME	YORUBA NAME
1.         Catfish	Clarias     gariepinus	(Aro)
2.         Catfish	Cbrysicbthys nigrodigitatus	(Obokun)
3.        Frank fish /Knife fish	Gymnorchus  niloticus	(Eja osan)
4.        Tilapia spp	Oreochromis niloticus	(Epiya)
5.         CARPS SPP	Gyprinus carpia / Heterotis niloticus	(Aika)
6.        Atlantic Herring	Clupea harengus	{titus}
7.        Mackerel	Scomber scrombrus	{kote}
8.        Horse mackerel	Trachurus capensis
9.        White croakers	Genyonemus limeatus	{Alapo}
10.    Blue whiting	Micromesistus potassou
11.    Sardinella	Clupeidae spp
12.    Banga fish              `	Ethmalosa fimbriata	(efolo)

                                  

  

1.5                                     IMPORTANCE OF FISH

1)         FISH AS FOOD: - fish is good food to man. The flesh is rich in proteins and fats. It contain vitamin A and D and also a source of phosphorous Among marine food fishes salmon, cod hearings, eels, tuna, mackerel and sardines and fresh water food fishes are mullet, catfish, trout are very important.

2)MEDICINAL PURPOSE AND DISEASE CONTROL:- Oil extracted from the liver of cod fishes is used to produce cod liver oil which is enriched in vitamin A and D is used as drug. In order to control mosquito larvae, fishes such as top minnows (Gambusia affinis Trichogaster, Esomus etc) are used. As these fishes eagerly feed on mosquito larvae, they are transmitted and distributed to the pond, lakes and water reservoirs so that diseases like malaria can be controlled. It is observed that different fishes and bye-product made from them are used as Ayurvedic medicines which help in treatment of duodenal ulcers, skin disease, night blindness weakness, loss of appetite, cough and cold , asthma, tuberculosis etc. Also, cavi al eggs for fertility treatment.

3)LEARNING/RESERARCH:- It is used for practical demonstration while teaching fishery in secondary school under classification and also in zoological laboratories fishes like dog fish (scoliodon), (perch )(perce) and carp (labeo) are used in dissection. Fish are used in different field (like genetics, embryology, animal bahaviour, pharmacology) of research work.

4)SPORTING ACTIVITIES AND REEREATION:- It is observed that fishes have been used in sport fishing by people of fishing parties of different countries. It is a very popular process of recreation. Fresh water perch and trout and marine tarpon are widely used as hunting fishes. It is a very common habit of having different local or foreign fishes like gold fish (curassuis auratus), Angel fish (pterphyllum), minnow (Gambusia affinis)in aquarin because they are so colufull and elegant. E.g Argungu fishing festival, Angling, Boating etc.

5)FISH SKIN AND LEATHER:- There are a huge importance in the field of manufacture where shark skin leather is used in making shoes and handbags. Carpenter and metal workers use unpolished, blunt skins of sharks and rays. There is a product called shagreen made from shark skin tanned with placoid scale upon it, it is used in many different field like polishing wood and ivory where it used as abrasive, as jewel box, fine book and sword handle covers.

6)INDUSTRIAL /COMMERCIAL USES :- large amount of unrefined oil of fishes like Bombay duck is used in the field of manufacture for making paints, pesticides, soaps. Pure gelatin substance is obtained from air bladder of fishes (Insinglass) is used to clarify wines and also used in producing glues.

7)FISH MEAL AND FISH MANURE: - small fragments of fishes from coming factories or unacceptable and unmarketable fishes are grinded into powder, dried and treated In fish meals which are used as food in poultry, pigs and for other domestic animals. Since these fishes are rich in calcium, protein, phosphorous. They can also be manure to Grape gardens, coffee and tea plants.

STRUCTURE QUESTIONS

1.            The following are fish predators except (a) bird (b) frog (c) moth (d) snake

2.            The following are marine fishes except (a) carp (b) croaker (c) mackerel (d) millet

3.            Monoculture in fish farming encourages the following except (a) control over the sex of the fish (b) familiarity with fish farming (c) intensive fish culture (d) prevents single disease to kill all the fish (e) selective harvesting

4.            The following are reason for embarking on aquaculture except (a) improving stocks in natural water bodies (b) production of bait fish for industrial fishing (c) means of recycling waste (d) production of ornamental fishes (e) recycling of hydro electricity

5.            Another name for tail fin is (a) dorsal (b) pelvic (c) caudal (d) pectoral (e) ventral

6.            Importance of fish farming includes the following except (a) pollution (b) employment (c) better land use (d) foreign exchange earning

7.            An example of a finned fish is (a) ray (b) mackerel (c) shark (d) shrimps

8.            The scientific name of African catfish is (a) chrischthys nigrodigtatus (b)clarias gariepinus (c) haterobrancus bidorsali (d) cymnarclus niloias

9.            The following are external features of a typical bony fish except (a)gill (b) anal fish (c)         dorsal fin (d) operculum (e) lateral line

10.          Fishes typically keep afloat due to the presence of (a) images (b) lateral lines (c) nostril (d) swim bladder (e) gills

11.          Which of the following is a fishing festival in Nigeria? (a) Durbar (b) Ogun (c) Argungu (d) Okonko (e) Eyo

12.          Which of the following is not a benefit of fish industry? (a) drug production (b) employment (c) pollution (d) food production (e) economy

13.          Which of the following is a fish sporting activity? (a) feeding (b)boating (c) preserving (d) swimming (e) smoking.

14.          Subsistence farming in fishery refers to the rearing of fish for (a) communal use (b) sales only (c) family and sales (d) entertainment (e) family use only

15.          Fish belong to the group of animals called (a) reptilian (b) coelenterate (c) molusca (d) crustacaces (e) pisces

16.          Omega-3 fatty acids are found in cold water oily fish which of the following is the best source of omega-3? (a) sardines (b) salmon (c)red snapper (d) tune

17.          What kind of imported fish do we eat most of in Nigeria? (a) frozen fish (b) canned fish (c) frozen prawn (d) iced fish

18.          Marine ecosystems that occur on the ocean floor are termed (a) pycnocline (b) pelagic (c) benthic (d) euphotic

19.          Which of the following is not a constraint to fish farming in Nigeria?(a) finance(b) fish feed (c) Net (d) Poaching.

20.         The common fish  found in Nigeria market      except (a)herring    (b)sardinella  (c) catfish (d) none of the above.

21.        The term fishery refers to (a) The culture of aquatic organisms (b) Catching of fish from the wild. (c)One aspects of fish production (d) All aspects of fish production.

  22.        In fisheries management, extensive, intensive, semi-intensive system are associated with (a) Capture fisheries (b) Artisanal fishing (c) Industrial fishing (d) Culture fisheries.

23.        Which of the following is not shell fish? (a) Carp (b) Crab (c) Oyster (d) Prawn.

  24.        Fish possesses the following features except (a) Gills (b) web (c) Swim bladder (d) operculum.

  25.        Fish belongs to the group of animals called (a) Coelenterata (b) Crustacea (c) Mollusca (d) Pisces.

 26.         Which of the following is a major division in fisheries? (a) Aquaculture (b) Artisanal and Culture (c) Capture and Culture (d) Integrated and Culture.

 27.         The following are non-finned fishes except (a) Catfish (b) Octopus (c) Oyster (d) Squid.

 28.         Another name for tail fin is (a) Anal (b) Caudal (c) Dorsal (d) Pelvic.

29.          Which of the following is not a challenge to aquaculture in Nigeria? (a) Parasite

                (b) Piping (c) Poaching (d) Pollution.

30.          The following are importance of fish farming except that it (a) encourages pollution. (b) generates foreign exchange. (c) is a source of employment. (d) is a source of income.

31.          Prawn belongs to the class of animals called (a) coelenterate (b) crustacea (c) mollusca (d) reptilian.

THEORY

1.            Mention five characteristics of fish that distinguish them from other animals.

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2.            List five importance of fish farming.

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3(a).       Define aquaculture.

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(b)          Mention two advantages and two disadvantages of aquaculture.

ADVANTAGES

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DISADVANTAGES

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4.    Name two types of fish that is commonly farmed in Nigeria.

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5.    Briefly explain the following:

 (a) Subsistence fishing.

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 (b) Wild fishing

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 (c) Fingerlings.

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6.            (a) State two differences between crustaceans and mollusc.

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(b) Give two examples in each case.

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7.    Enumerate five challenges of fish farming in Nigeria.

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8.    List  three causes of fish shortage in Nigeria.

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9.    State four differences between intensive and extensive system of aquaculture.

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10.  State two characteristics of each of the following division of fisheries.

(a) Capture fisheries

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 (b) Culture fisheries.

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11.  Name three types of management systems in aquaculture.

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12.  Describe three types of aquaculture.

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13.  Differentiate between artisanal fisheries and industrial fisheries.

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14.  Specimen  A is  CATFISH and  specimen B is TILAPIA FISH

 State four similarities and differences between specimens A and B.

SIMILARITIES

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DIFFERENCES

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