Site Selection and Design of Prawn Hatcheries Along the Coastline of India

Table 1. Brackish water prawn farming areas and marine prawn landings in India.

State	Potential brackish water culture area (ha)^a	Traditional farms (ha)^a	Existing & planned farms (ha)^b	1984–85 prawn landings (Mg)^c
Gujarat	376,000		600	13,787
Maharashtra	81,000		100	45,416
Karnataka	8,000	5,000	50	5,547
Goa	19,000		40	3,903
Kerala	243,000	5,000	200	37,168
Tamil Nadu	80,000		250	12,567
Andhra Pradesh	200,000		500	7,647
Orissa	299,000	20,000	800	2,496
West Bengal	405,000		400	1,034
Pondicherry	-		30	711
Andamans	-		-	199
Larger trawlers	-		-	58
Total	1,711,000	30,000	3,500	130,533

^a Dandekar and Upare, 1985
^b N.P.Bhakta, pers. comm.
^c CMFRI, 1986

Table 2

Criteria for Site Selection of Prawn Hatchery

Land availability
Hydrology
1. Salinity > 30 ppt - away from rivers and freshwater sources,
2. Clean and unpolluted water - away from industrial and agricultural pollution e.g. factories, ricelands,
3. Clean with no turbidity, and
4. No heavy metals (if inshore well is used).
Topography
1. < 50 m intertidal area (if water intake is pipe),
2. 2–3 m above high tide level,
3. Sandy or rocky-sandy substratum, and
4. Protected from cyclones, storms and other wind and wave action.
Source of Broodstock and Spawners
1. Wild spawners and broodstock - offshore trawlers and traditional fishing gear e.g. bottom set gill nets, and
2. Pond broodstock - farms.
Infrastructure
1. Availability of electricity,
2. Accessibility by road,
3. Proximity to farms and other markets for fry, and
4. Freshwater supply (for hatchery and domestic needs).
Social services
1. Proximity to towns for amenities (housing, market, educational and medical services) for hatchery staff, and
2. Security.

Table - 3 - Summary of field survey data of prospective prawn (Penaeus monodon) hatchery sites along the coastline of India

	Madhavapur (Gujarat)	Chandrabhagar (Orissa)	Gudlavanipalem (Andhra Pradesh)	Bimlipatam (Andhra Pradesh)	Valinokkam (Tamil Nadu)
Location	21°15'N, 69°57'E	19°53'N, 86°5'E	17°47'N, 83°23'E	17°53'N, 83°27'E	9°7'N, 78°30'E
Climate type	I	IV (to serve type II also)	IV	IV	V
Date & time of survey	16-4-86, 0930 hr	23-4-86, 1230 hr	22-4-86, 0930 hr	22-4-86, 1100 hr	20-4-86, 0830 hr
Salinity (ppt)	33 ^a	35 ^b	35 ^b	36 ^b	36 ^b
Temperature (oC)	23	27	21	21	29
	Veraval, 1985				Puri, 1985
	min 14.5°C, Jan.				min 22.0°C, Jan
	max 32.4°C, June				max 31.5°C, May
Water quality	Clear (sandy due to wave action)	Clear	Clear	Turbid (after rain)	Very clear
Substratum	Sand & limestone rock	Sand	Sand	Sand	Sand
Winds	ave. 50–40 kph (max. 150 kph)	ave. 60 kph (max. 160kph)	ave. 60 kph	ave. 60 kph	Protected by Sri Lanka Island and natural bay.
Proposed seawater intake	Inshore well	Inshore well	Inshore well	Inshore well	Sea bottom pipe (intertidal area 30 m wide x 2 m high)
Broodstock & spawner sources	Trawler(Veraval); staked gill net (Dwarka); future farma - Bulsar area	Trawlers; traditional gill nets; confined ponds (Chilka Lake)	Numerous trawlers & mechanised boats; bottom set gill nets	Trawlers & mechanised boats; bottom set gill nets	Trawlers; bottom set gill, nets
1	2	3	4	5	6
Farms (existing & potential) in state	Singaoh salt ponds; Bulsar - planned	300 ha Chilka Lake 440 ha proposed	600 ha existing 1,000 ha planned 1986–87.	600 ha existing 1,000 ha planned, 1986–87	50 ha existing 200 ha planned
Electricity	Available	Available	Available	Available	Available
Road	Accessible	To be extended 21 km	Accessible	Accessible	To be extended
Freshwater supply	Dig shallow well	Dig shallow well	Dig shallow well	Dig shallow well	Dig shallow well
Proximity to towns (services & amenities)	½ km from Mangrol	2 km from Konarak (10,000 pop.)	3 km from Vishag (500,000 pop.)	Close to Bimlipatam town, 23 km from Vishag	0.5 km from village (5,000 pop.)

^a Salinity-conductivity-temperature meter
^b Atago S-100 hand refractometer

Table 4. Rates of Stocking, survival and water exchange for P. monodon hatchery with rated capacity of 25 × 10⁶PL/yr.

Tank	Stage ^a	Maturation/ hatching/ survival rate(%)	Stocking ^b			Total water vol°(m³)	Daily water exchange		Peak load
Tank	Stage ^a	Maturation/ hatching/ survival rate(%)	Initial No.	Final no.	Density	Total water vol°(m³)	Rate(%)	Vol.(m³)	Peak load
Maturation Tanks	IF to S/E	70	270	189	2.5/m³	108	200	216	9 m³/hr: 0000 – 2100 hr
			(189 F/60 days = 47 F/15 days at 300 × 10³ E = 14 × 10⁶ E)
Spawning Tanks	E to N	70	14 × 10⁶	10 × 10⁶	3,000/L	8	100	8
Larval Tanks	N to PL₅	25	10 × 10⁶	2.5 × 10⁶	100/L	100	30	30
Postlarval Tanks	PL₅ to PL₂₀	50	2.5 × 10⁶	1.25 × 10⁶	5,000/m³	500	20	100	a) 35 m³/hr: 0800 – 1200 hr
Natural Food Tanks						20		(20)
Training Tanks						4	30	1.5	b) 5 m³/hr: 1300 – 1700 hr
Broodstook Holding Tanks						7	50	4
Total						750		380

^a IF - immature females, S-spawners, E-eggs, N-nauplii, PL-Post larvae

^b One run, maturation tank = 60 day
larval tank = 15 days
post larval tank = 15 days

Table 5 - Details of Tank Construction for a P. Monodon hatchery with rated capacity of 25 × 10⁶ PL/yr.

	Tank	Dimensions	No.	Unit Vol. (m³)	Total Vol. (m³)	Shape	Material	Building
A.	Maturation area:
	Maturation tanks	4 m Æ × 1.2 m	9	12	108	Circular	Concrete	Dark roof, walls
	Spawning tanks	1 m Æ × 0.35 m	40	0.2	8	Conical	fibreglass wooden stand
	Broodstock
	Holding tanks	2 m × 1 m × 0.6 m	7	1	7	Oval	Oval
B.	Larval rearing area:
	Larval tanks	5 m × 1 m × 1 m	20	5	100	Rectangular	Concrete	30% skylight, walls
	Natural food						fiberglass	skylight, open
	Tanks	2 m × 1 m × 0.6m	20	1	20	Oval
	Training tanks	1 m Æ × 0.35 m	20	0.2	4	Conical	fiberglass with wooden stand	30% skylight, walls
C.	Others:
	Post Larval Area:
	Post Larval tanks	5 m × 2 m × 1 m	50	10	500	Rectangular	Concrete	Skylight, open.

Table 6 - Assumptions and Guidelines for Prawn Hatchery

Production level = 25 × 10⁶ PL₂₀/yr or 1.25 × 10⁶ PL₂₀/run
Operational period = 10 mo (2 mo for repairs & maintenance)/yr

1 run = 15 days or 2 run/mo

1 yr = 20 runs
Seawater intake
1. inshore well - Madhavapur, Chandrabhaga, Gudlavanipalem
2. bottom intake
  pipe- Valinokkam
Seawater Supply
1. maturation tanks - direct pumping from well or sump pit or require reservoir of 20–50 cu.m. (depending on no.of hours pumping).
2. larval, postlarval and other tanks - require total reservoir capacity of 200 cu.m.
Seawater filtration
1. inshore well - no filter required if naturally filtered through sand.
2. sand filter - for sea bottom pipe (Valinokkam).
3. inline filters - to spawning, larval and algal tanks. (Cartridge etc)
Average air requirement of 0.35 m³/hr/1 m³ water (1 m depth).
Ratio by volume, 1 natural food/algal tank : 5 larval tanks 1 larval tank : 5 postlarval tanks.