Nursery Pond Management
Objectives:
To obtain required amount of desirable species at desired time at desired price all the year round.
After completing these stages of management the nursery pond is prepared for rearing fry and fingerlings.
The next stage is to select culturable species for stocking in the prepared pond and other management.
If we prepare a good nursery pond we will get a good production .
2. • A place where young fry or
fingerlings are grown for sale or
for planting elsewhere.
• Area: 10-25 decimal
• Carp culture in ponds is basically a
three-tier culture system.
• Where the first step begins with the
rearing of spawn up to fry (2–3 cm)
stage for 2–3 weeks in nursery ponds.
• To ensure high rate of survival and
growth during all the three stages of
rearing.
Nursery
Management
4. The pond which is used for growing hatchlings, spawn, fry to
advanced fry or fingerlings for a period of about 40-60 days is
called nursery pond.
5. The nursery ponds should have the following characters-
Type of pond : Seasonal ponds are better for nursery management.
Shape: Ponds should be rectangular.
Slope: 2:1 or 1.5:1(per unit length : per unit depth).
Size:10-25decimal in size is the most appropriate for dhani fry and 25-
100 decimal for fingerling production.
Depth: Shallow ponds,1-1.5m depth is preferable with an
arrangement of drainage.
Pond dyke: Pond dyke should be compact and high enough to protect
from flooding.
6. Area or place of pond: Pond should get enough sunlight throughout the
day period.
Soil type: Clay soil is suitable for nursery pond.
Soil pH: 6.5 to 9.0
Preparation of a nursery pond
Management of a nursery pond can be discussed under the following
headings-
a) Control of aquatic weeds.
b) Control of weed fish or undesirable species.
c) Liming.
d) Water supply.
e) Fertilization.
7. Different weeds present in the pond water which directly or indirectly
hampers the production of fish and fry are called aquatic weeds.
Use of aquatic weeds
Besides disadvantages of aquatic weeds , it has also advantages .The
advantages of aquatic weeds are-
a) Chara , duckweeds, some other soft green grasses are uses as
feed for grass carp and sorpunti.
b) Water hyacinth and other aquatic weeds are used as component
of compost.
8. Preventing light penetration and reducing the photosynthesis.
Decreasing dissolved oxygen.
Limiting space for culturable fish.
Hampering the netting operation.
The aquatic vegetation can be controlled by the following
methods-
Mechanical or manual method: netting , dredging etc.
Biological method: Introduction of herbivores fish species such as
grass carp and common carp.
Chemical method:
CuSo4.5H2O: 0.5 ppm for 7 days before liming to control algal weeds.
9. The weed fish can be controlled by the following ways-
Repeated netting or dragging .
Pond drying or dewatering.
The advantages of pond drying are-
Kill insect and parasites.
Increase fertility of the soil.
Stimulate the growth of algae.
Release off gas from the bottom.
10. Poisoning or use of chemicals:
Organic source:
Rotenone:2-3mg/l.
Tea seed cake:145-150g/decimal at 30cm water depth.
Tobacco dust: 0.8-1.6kg/decimal at 30cm water depth.
Inorganic source:
Phostoxin:0.25-0.30mg/l at 1m water depth.
11. Types of liming:
Calcium Carbonate CaCO3
Calcium Oxide CaO
Calcium Hydroxide Ca(OH)2
Dolomite CaMg(Co3)2
Zipsum CaSO4.2H2O.
Usually hydrated lime and quick lime is commonly used in nursery
pond because of their availability.
Rate of liming depends on soil pH and soil type.
Dosage: 1kg CaCO3 per decimal.
12. After 3 days of liming , water should be supplied in nursery pond. The
sources of water are-
Perennial streams and rivers.
Springs.
Rainfall.
NB:
During the supply of water an important precaution is that fine meshed
net or screen should be used at the end of the pipe to prevent the
entrance of undesirable species or debris. Desirable depth of the pond
is at least 1m or not more than 3-4ft.
13. Fertilization
Manuring and fertilization is important for the following
reasons-
To keep the hygienic condition of the water body.
To increase the primary productivity of the pond.
Doses of fertilizers:
Organic manure: 1 KG per decimal
Urea: 50gm per decimal
TSP: 100gm per decimal
14. Stocking Density
First Stage:
5-10 gm carp renu per decimal.
Reared upto 60-90 days
Second Stage:
50-100 gm carp renu per decimal.
Reared upto 21-30 days.
Success rate is higher in 2nd stage.
An insect locally called Haushpoka is the biggest enemy of carp renu.
To avoid this, it is recommended that 10 mg Sumithion per decimal used
before renu introduction.
Then dead Haushpoka are cleaned up by fine meshed net according to their
diameter.
15. After completing these stages of management the nursery pond is
prepared for rearing fry and fingerlings.
The next stage is to select culturable species for stocking in the
prepared pond and other management.
If we prepare a good nursery pond we will get a good production .