FISHERY ANSWERS
WAEC 2016

Q1-
-Livebearears
-Anabantoids
– Loaches
-carp Family
-Cichlids
-Characins
-Corydoras
– Arowanas
-Catfish

1b
1-Product flow

Fish product flow can follow various channels
from the fish producer including fisherfolk
and aquaculturalist to the final consumer and
can involve varying number of stages.
Therefore, the fish market was divided into
four main stages: the producer stage, the
wholesaler stage including processing, the
retailer stage, and the consumer stage
including the export and institutional
consumer markets.

2-Money flows
The above sections examined the product
channels from fish producers to fish
consumers in terms of sales. The following
paragraphs discuses the method of payment to
the fish producfers.

3-Sales systems
In this section, examines how fish was traded
in the market and how market operators could
come together for fish trading.
==================================
Q6
-intensive farming

Phosphorous is an essential mineral for fish,
as well as usually being the limiting nutrient
in aquatic ecosystems.
Fish obtain P almost exclusively from their
diet. Most diets used in intensive culture have
P in excess to the needs of the fish, or in a
form which partially unavailable to the
animal. Surplus P is excreted either by the
kidneys or in the feaces.
In intensive pen or cage farming, for every kg
of fish harvested, the environment can be
enriched by as much as 0.75 kg of Carbon,
0.023 kg of Phosphorus, and 0.1kg of Nitrogen.
This can be calculated in a variety of ways,
using measurements on the water body, or by
using the published data on P content of feeds,
the FCR (Food Conversion Ratio), and the P
content of fish carcasses.
The concentration of total P in a water body is
determined by the P loading, the size of the
water body (surface area, mean depth), the
flushing rate (what perdentage of the total
volume is lost anually through over flow) and
the part of P permanently lost in the
sediments.
In temperate climates, it is best to determine
the total P concentrations during the spring
overturn, as during most of the year
stratification of the water column might result
in faulty measurements. In tropical climates,
total P should be determined as the mean
measured surface P over one year.

-extensive farming

Predicting the effects of extensive farming on
an aquatic ecosystem is very imprecise. It is
based on the relation between the primary
productivity of the water body and the
production of fish. Theoretically, 10–15% of
the primary production could be converted
into fish (tilapia) tissue. This theoretical
assimilation value is 20 timew better than
what happens in well managed fish ponds,
which in itself is much more efficient than in
nature. In highly productive ponds, the figure
is about 1.4%, and about 1.3% in less
productive systems. Estimates of extensive
sage farming, where the fish are more
concentrated and than in enclosures and
depend largely on plankton, very 1.0% to
3.5% of the primary productivity. ACURATE FISHERY OBJ ANSWERS
1-10CADCBABDBB
11-20ABBBAADCAA
21-30DBABBDCCDD
31-40ABCAABDBBD
41-50CCADACDDCC

FISHERY ANSWERS
WAEC 2016

Q1-
-Livebearears
-Anabantoids
– Loaches
-carp Family
-Cichlids
-Characins
-Corydoras
– Arowanas
-Catfish

1b
1-Product flow

Fish product flow can follow various channels
from the fish producer including fisherfolk
and aquaculturalist to the final consumer and
can involve varying number of stages.
Therefore, the fish market was divided into
four main stages: the producer stage, the
wholesaler stage including processing, the
retailer stage, and the consumer stage
including the export and institutional
consumer markets.

2-Money flows
The above sections examined the product
channels from fish producers to fish
consumers in terms of sales. The following
paragraphs discuses the method of payment to
the fish producfers.

3-Sales systems
In this section, examines how fish was traded
in the market and how market operators could
come together for fish trading.
==================================
Q6
-intensive farming

Phosphorous is an essential mineral for fish,
as well as usually being the limiting nutrient
in aquatic ecosystems.
Fish obtain P almost exclusively from their
diet. Most diets used in intensive culture have
P in excess to the needs of the fish, or in a
form which partially unavailable to the
animal. Surplus P is excreted either by the
kidneys or in the feaces.
In intensive pen or cage farming, for every kg
of fish harvested, the environment can be
enriched by as much as 0.75 kg of Carbon,
0.023 kg of Phosphorus, and 0.1kg of Nitrogen.
This can be calculated in a variety of ways,
using measurements on the water body, or by
using the published data on P content of feeds,
the FCR (Food Conversion Ratio), and the P
content of fish carcasses.
The concentration of total P in a water body is
determined by the P loading, the size of the
water body (surface area, mean depth), the
flushing rate (what perdentage of the total
volume is lost anually through over flow) and
the part of P permanently lost in the
sediments.
In temperate climates, it is best to determine
the total P concentrations during the spring
overturn, as during most of the year
stratification of the water column might result
in faulty measurements. In tropical climates,
total P should be determined as the mean
measured surface P over one year.

-extensive farming

Predicting the effects of extensive farming on
an aquatic ecosystem is very imprecise. It is
based on the relation between the primary
productivity of the water body and the
production of fish. Theoretically, 10–15% of
the primary production could be converted
into fish (tilapia) tissue. This theoretical
assimilation value is 20 timew better than
what happens in well managed fish ponds,
which in itself is much more efficient than in
nature. In highly productive ponds, the figure
is about 1.4%, and about 1.3% in less
productive systems. Estimates of extensive
sage farming, where the fish are more
concentrated and than in enclosures and
depend largely on plankton, very 1.0% to
3.5% of the primary productivity. ACURATE FISHERY OBJ ANSWERS
1-10CADCBABDBB
11-20ABBBAADCAA
21-30DBABBDCCDD
31-40ABCAABDBBD
41-50CCADACDDCC