2024 NECO Fisheries Objectives And Essays Answers

FISHERY OBJ
01-10: EBEDDEDCDE
11-20: DDAEBCCDBA
21-30: DCDBDEABEA
31-40: ECCAABAEBB
41-50: BADBAACADA
51-60: ABCBBEBCAD

NECO FISHERIES*

*NUMBER ONE*

(1a)
(i) Reduced availability of dissolved oxygen due to the dense growth of aquatic weeds, which can lead to suffocation and mortality of fingerlings.
(ii) Interference with the movement and feeding of fingerlings, as the weeds can create a physical barrier and obstruct their access to food.
(iii) Provision of hiding places for predators, which can increase the risk of predation on the fingerlings.
(iv) Accumulation of waste and decomposing organic matter, which can lead to the buildup of toxic substances and deterioration of water quality, affecting the overall health and growth of the fingerlings.

(1bi)
Spillway: A spillway is a structure designed to safely pass excess water from a dam, reservoir, or other water-retaining structure. It helps to prevent the overtopping and potential failure of the structure during high-flow events.

(1bii)
Fish sampling: Fish sampling is the process of collecting a representative sample of fish from a water body to assess the population characteristics, such as species composition, size distribution, and abundance. This information is crucial for fisheries management and monitoring.

(1biii)
Cropping: In aquaculture, cropping refers to the harvesting of fish or other aquatic organisms from a culture system. It involves the selective removal of individuals based on their size, age, or market demand, ensuring the efficient utilization of the available resources and maintaining the productivity of the system.

(1biv)
Feeding regime: The feeding regime in aquaculture refers to the pattern and frequency of feeding the cultured organisms. It involves the determination of the appropriate amount, timing, and composition of the feed to meet the nutritional requirements of the species and optimize their growth and health.

(1ci)
[In a Tabular Form]

-Intensive culture system-
(PICK ANY TWO)
(i) High stocking density
(ii) Reliance on artificial feeding
(iii) Controlled environmental conditions
(iv) Higher capital and operational costs
(v) Increased risk of disease outbreaks
(vi) Higher productivity per unit area

-Extensive culture system-
(PICK ANY TWO)
(i) Low stocking density
(ii) Reliance on natural food sources
(iii) Less control over environmental factors
(iv) Lower capital and operational costs
(v) Lower risk of disease outbreaks
(vi) Lower productivity per unit area

(1cii)
(PICK ANY FOUR)
(i) Provision of a reliable source of animal protein
(ii) Generation of employment opportunities
(iii) Diversification of the agricultural sector
(iv) Contribution to food security and poverty alleviation
(v) Potential for export and foreign exchange earnings
(vi) Promotion of sustainable utilization of aquatic resources

(2a)
Diagram

(2b)
(PICK ANY FOUR)
(i) Increased stress
(ii) Reduced metabolic rates
(iii) Behavioral changes
(iv) Mortality
(v) Impaired reproduction
(vi) Altered ecosystem dynamics

(2ci)
(PICK ANY THREE)
(i) Nutritional Content
(ii) Palatability
(iii) Digestibility
(iv) Stability in Water
(v) Appropriate Size and Shape

(2cii)
(PICK ANY TWO)
(i) Nutritional Content: Fish feed must contain a balanced mix of proteins, fats, carbohydrates, vitamins, and minerals to ensure the fish get all the essential nutrients needed for growth, health, and reproduction.

(ii) Palatability: The feed must be appealing in taste and smell to the fish, encouraging them to eat it readily. This ensures the fish consume enough feed to meet their nutritional requirements.

(iii) Digestibility: High digestibility means the feed can be easily broken down and absorbed by the fish’s digestive system, allowing them to gain maximum nutritional benefit and reducing waste output.

(iv) Stability in Water: The feed should maintain its structure and nutritional value when submerged, preventing it from disintegrating too quickly. This helps reduce water pollution and ensures the fish can eat it before it breaks apart.

(v) Appropriate Size and Shape: Fish feed should be designed to match the size and feeding habits of the specific fish species. This makes it easier for the fish to consume and reduces feed waste.

(2ciii)
(PICK ANY FIVE)
(i) Tank
(ii) Filter
(iii) Heater
(iv) Lighting
(v) Substrate
(vi) Water Conditioner
(vii) Air Pump and Air Stones
(viii) Decorations
(ix) Thermometer
(x) Test Kits
(xi) Fish Food
(xii) Net

(3a)
(PICK ANY FIVE)
(i) Broodstock selection and management: Selecting healthy, sexually mature male and female fish with desirable characteristics.
(ii) Hormonal induction of spawning: Administering hormones to induce the release of eggs and sperm from the broodstock.
(iii) Egg fertilization: Mixing the released eggs and sperm to facilitate fertilization.
(iv) Egg incubation: Providing the appropriate conditions (temperature, water quality, etc.) for the fertilized eggs to develop and hatch.
(v) Larval rearing: Caring for the newly hatched larvae, providing them with the necessary nutrients and environmental conditions for growth and survival.
(vi) Fingerling production: Rearing the larvae into fingerlings, which are then ready for stocking in nursery or grow-out ponds.

(3bi)
(PICK ANY TWO)
(i) Reduce water supersaturation levels by aeration or adjusting water flow.
(ii) Identify and eliminate the source of gas supersaturation (e.g., clogged or malfunctioning aeration equipment).
(iii) Quarantine affected ponds to prevent the transfer of infected fish to other ponds.
(iv) Regularly monitor water quality parameters, especially dissolved gas levels.
(v) Improve water circulation and mixing to prevent localized gas supersaturation.
(vi) Treat affected fish with appropriate medications or remedies to alleviate the condition.

(3bii)
-Extensive fish farming-
(PICK ANY TWO)
(i) Low stocking density
(ii) Reliance on natural food sources
(iii) Minimal external inputs (e.g., feed, fertilizers)
(iv) Lower capital and operational costs
(v) Lower productivity per unit area
(vi) Dependence on natural environmental conditions

-Intensive fish farming-
(PICK ANY TWO)
(i) High stocking density
(ii) Reliance on artificial feeding
(iii) Requirement for external inputs (e.g., feed, aeration, water treatment)
(iv) Higher capital and operational costs
(v) Higher productivity per unit area
(vi) Greater control over environmental conditions

(3ci)
Monoculture refers to the cultivation or farming of a single species of organism, such as a single fish species, in a given aquaculture system.

(3cii)
(PICK ANY THREE)
(i) Chlorine
(ii) Iodine
(iii) Formalin
(iv) Hydrogen peroxide
(v) Potassium permanganate
(vi) Benzalkonium chloride

(3ciii)
(PICK ANY FOUR)
(i) Viral Nervous Necrosis (VNN)
(ii) Viral Hemorrhagic Septicemia (VHS)
(iii) Infectious Pancreatic Necrosis (IPN)
(iv) Koi Herpesvirus Disease (KHV)
(v) Spring Viremia of Carp (SVC)
(vi) Infectious Hematopoietic Necrosis (IHN)

(4a)
(PICK ANY FOUR)
(i) Water quality
(ii) Stocking density
(iii) Transport duration
(iv) Acclimatization
(v) Oxygen supply
(vi) Handling and containers

(4bi)
(PICK ANY THREE)
(i) Higher catch and production volumes
(ii) Improved efficiency and technology
(iii) Access to larger and more distant fishing grounds
(iv) Potential for export and international trade
(v) Economies of scale and profitability
(vi) Ability to meet the growing demand for seafood

(4bii)
(i) Potential for overfishing and depletion of fish stocks
(ii) Environmental impact from large-scale fishing operations

(4ci)
[In Tabular Form]

-Fresh fish-
(PICK ANY TWO)
(i) Shorter shelf life
(ii) Requires refrigeration or ice for preservation
(iii) Milder flavor
(iv) Softer texture
(v) Higher moisture content
(vi) Shorter preparation time

-Smoked fish-
(PICK ANY TWO)
(i) Longer shelf life
(ii) Can be stored at room temperature
(iii) Stronger, more distinct flavor
(iv) Firmer texture
(v) Lower moisture content
(vi) Longer preparation time (smoking process)

(4cii)
(PICK ANY FOUR)
(i) Water quality management
(ii) Feeding and nutrition management
(iii) Disease prevention and treatment
(iv) Pond/tank maintenance and cleaning
Stocking density and population control
(vi) Harvest and post-harvest handling

(4ciii)
Length = 92,000 cm
Breadth = 62,000 cm
Area = Length x Breadth
Area = 92,000 cm x 62,000 cm
Area = 5,704,000,000 cm²
Area = 5,704,000 m²

Therefore, the area of the rectangular pond is 5,704,000 m²

(5a)
(PICK ANY FOUR)
(i) Ice
(ii) Salt
(iii) Smoking
(iv) Canning
(v) Freezing
(vi) Drying/dehydration

(5b)
(PICK ANY TWO)
(i) Tilapia have a compressed, laterally flattened body, WHILE catfish have a more rounded, elongated body.
(ii) Tilapia have smooth, scaleless skin, WHILE catfish have a rough, scaleless skin.
(iii) Tilapia are primarily herbivorous, feeding on aquatic plants and algae, WHILE catfish are omnivorous, feeding on a variety of food sources.
(iv) Tilapia prefer warm, shallow waters, WHILE catfish can thrive in a wider range of water bodies, including rivers, lakes, and ponds.
(v) Tilapia are more tolerant of poor water quality and can survive in a wider range of pH and dissolved oxygen levels, while catfish are more sensitive to water quality.
(vi) Tilapia are widely farmed and consumed globally, while catfish are more regionally popular, with higher demand in some parts of the world.

(5ci)
(i) Disease outbreaks
(ii) Water quality issues (e.g., low dissolved oxygen, pH imbalance, toxic compounds)
(iii) Predation by other animals
(iv) Stress due to overstocking, poor handling, or environmental changes

(5cii)
(PICK ANY THREE)
(i) Surface water (rivers, lakes, ponds)
(ii) Groundwater (wells, boreholes)
(iii) Rainwater harvesting
(iv) Desalination of seawater
(v) Recycled wastewater
(vi) Municipal/public water supply

(5ciii)
(PICK ANY THREE)
(i) Claws (chelae)
(ii) Antennae
(iii) Compound eyes
(iv) Segmented body
(v) Swimmerets (abdominal appendages)
(vi) Tail (telson)
(vii) Exoskeleton