6. REFERENCES

BARICA, J. 1976 Nutrient dynamics in eutrophic inland waters used for aquaculture. SCS/76/WP/24. 29p.

BIO-RESOURCES INTERNATIONAL, INC. 1980 Reports of activities Laguna de Bay fishery development project.

ESTRELLA, J.J. 1981 Milkfish culture in pens in Laguna de Bay. Paper presented in APDEM IV. UP Diliman, Q.C. Mimeographed, 21p.

ESTRELLA, J.J. 1981 Personal communication.

GUERRERO, R.D. 1981 Personal communication.

MANE, A.M. 1979 Cage culture of tilapia in Laguna de Bay. Technical consultation on available aquaculture technology in the Philippines, Iloilo. 4p.

MANE, A.M. 1981 Management and maintenance of fisheries in Laguna de Bay. Lecture given in training in small-scale pen culture for finfish. Sponsored by UNDP/FAO through SCSP. Mimeographed. 8p.

MERCENA, E. 1981 Cage culture of tilapia. Personal communication.

NICOLAS, E.S. and A.R. LIRERO. 1977 A socio-economic study of fishpen aquaculture in Laguna lake, Philippines. Paper presented at the second Biennial Meeting of the Agricultural Economics Society of Southeast Asia. Iloilo, Mimeographed. 15p.

PCARR. 1980 Technology: cage culture of tilapia. Philippine Council for Agriculture and Resources Research publication. Vol. 2 No. 1. 11p.

PULLIN, R.S.V. 1981 Fish pens of Laguna de Bay, Philippines, ICLARM Newsletter. Vol. 4, No. 4, pp. 11–13.

Table 1.
Combined Profitability of Fishpen and Cage Culture
Size of fishpen (a)	No. of Sub-borrowers	Needed investment	Estimated total	Profit per family
2.5 (w/ 2 cages)	1–2 families	180 000–200 000	72 464	36 232
5.0 (w/ 3 cages)	1–3 families	260 000–290 000	164 386	54 795
10.0 (w/ 5 cages)	2–5 families	350 000–420 000	374 399	74 880

Table 2.
Profitability of Pure Cage Culture of Tilapia Nilotica
(No Supplemental Feeding)
	ITEM	Module Size (ha/cage)
	ITEM	2.5 ha/ 50 cages	5 ha/ 100 cages	10 ha/ 200 cages	25 ha/ 500 cages
1.	Total capital investment, barriers and cages ()	273 504	523 056	1 011 312	2 454 649
2.	Capital investment/cage ()	5 470	5 231	5 057	4 910
3.	Total production (kg) at 10/kg ()	84 000 884 000	168 000 1 680 000	336 000 3 360 000	840 000 8 400 000
4.	Total expenses ()	365 268	717 723	1 416 558	3 499 785
5.	Total net income ()	474 732	962 270	1 943 442	4 900 215
6.	Net income/cage ()	9 495	9 632	1 943 442	4 900 215
7.	Investment and operational expense per cage, items 2 and 4 ()	12 776	12 400	12 140	11 910

Table 3.
Annual Production and Sale Per Sale of Module
(After BRI Consultants Reports, 1980)
	ITEM	2.5 ha.		5.0 ha.		10.0 ha.
	ITEM	Produce Kg	Sale	Produce Kg	Sale	Produce Kg	Sale
1.	Summer Crop
	a) Milkfish (200 g) at 10.00/kg b) Tilapia (150 g) at 100.00/kg	5 400 2 880	54 000 28 800	10 800 4 320	108 000 43 200	21 600 7 200	216 000 72 000
2.	Winter Crop
	a) Milkfish (225 g) at 13.00/kg b) Tilapia (240 g) at 12.00/kg	6 075 4 608	78 975 55 296	12 150 6 912	157 950 82 944	24 800 11 520	322 400 138 240
	Total Milkfish	11 475	132 975	22 950	265 950	45 900	538 400
	Total Tilapia	7 488	84 096	11 232	126 144	18 720	210 240
	Total Annual Gross	18 963	217 071	34 182	392 094	64 620	748 640

Table 4.
Income Statement Per Module Size
(After BRI Consultants Report, 1980)
I. MARKETING BY PFMA
	Particulars	MODULE
	Particulars	2.5 ha.	5.0 ha.	10.0 ha.
A.	Gross Sales: 70% milkfish produce	93, 083.00	186 165.00	376 880.00
B.	Less: Cost of Marketing (70%)	6 024.00	12 049.00	24 097.00
	Fingerlings	34 680.00	65 520.00	127 200.00
	Feeds	9 000.00	13 500.00	22 500.00
	License	1 000.00	2 000.00	4 000.00
	Permit	10.00	10.00	10.00
	Harvest nets	2 640.00	3 960.00	5 280.00
	Amortization	57 076.00	80 281.00	115 552.00
	Total Expenses	110 430.00	177 320.00	298 639.00
C.	Surplus (Deficit)	(17 347.00)	8 845.00	78 241.00
II. MARKETING BY SUB-BORROWERS
A.	Gross Sales:
	Milkfish — 30%	39 892.00	79 785.00	161 520.00
	Tilapia — 100%	84 096.00	126 144.00	210 240.00
		123 988.00	205 929.00	371 760.00
B.	Less: Cost of operating and
	Maintenance
	Boat	16 556.00	22 870.00	28 510.00
	Pen	4 648.00	6 073.00	9 071.00
	Marketing	8 198.00	13 588.00	24 367.00
	Contingencies	4 775.00	7 857.00	13 654.00
	Total Expenses	34 177.00	50 388.00	75 602.00
	Surplus (Deficit)	89 811.00	155 541.00	296 158.00
	Total Net Income	72 464.00	164 386.00	374 399.00
	Net Income Per Family	36 232.00	54 795.00	74 880.00

Table 5.
Basic Assumptions for Pure Cage Culture of *Tilapia nilotica*
1.	Two crops per year — summer and cold months
2.	Stocking density: no feeding — 20/sq.m. with feeding — 40/sq.m.
3.	Supplementary feeding (fine rice bran 5% of fish biomass) 7 650 – 10 200 kg
4.	Cost of feeds — 1.50/kg
5.	Survival rate — 80%
6.	Size of fish at harvest — 150–200 g
7.	Market price — 10/kg
8.	Cost of fingerlings — 0.15/pc
9.	Repairs & Maintenance — 10% of cost of bamboo, nets and their installation
10.	Marketing cost — 0.75/kg
11.	Harvesting labour — 2 man-days/cage at 25/day
12.	Fishpen permit — 400/ha/year
13.	Registration fee — 10
14.	Interest charges — 16%
15.	5 years to pay; 1 year gross
16.	Amount amortized is the loan equivalent to the initial capital investments

Table 6.
Gross Income, Expenses and Net Income
(No Feed Supplement)
ITEM	MODULE SIZE
ITEM	50 cages (2.5)	100 cages (5.0)	200 cages (10)	500 cages (25)
GROSS INCOME	840 000	1 680 000	3 360 000	8 400 000
EXPENSES1
Fingerlings	90 000	180 000	360 000	900 000
Labour (Harvesting)	2 500	5 000	10 000	25 000
Repairs & Maintenance	27 350	52 306	101 131	245 465
Permit	1 000	2 000	4 000	10 000
Registration Fee	10	10	10	10
Amortization	139 386	269 837	526 450	1 286 680
Marketing Cost	63 000	126 000	252 000	630 000
Contingencies (13% of the
above expenses)	42 022	82 570	162 967	402 630
TOTAL	365 268	717 723	1 416 558	3 499 785
NET INCOME	474 732	962 270	1 943 442	4 900 215
Per Cage	9 495	9 623	9 717	9 800
Per Kg	5.65	5.73	5.78	5.83

Table 7.
Gross Income, Expenses and Net Income
(With Feed Supplement)
	50 cages (2.5)	100 cages (5.0)	200 cages (10)	500 cages (25)
GROSS INCOME	1 680 000	3 360 000	6 720 000	16 800 000
EXPENSES1
Fingerlings	180 000	360 000	720 000	1 800 000
Labour (Harvesting)	2 500	5 000	10 000	25 000
Repairs & Maintenance	27 350	52 306	101 302	245 465
Permit	1 000	2 000	4 000	10 000
Registration Fee	10	10	10	10
Amortization	364 548	720 161	1 426 741	2 187 328
Marketing Cost	126 000	253 000	504 000	1 680 000
Feeds	630 000	1 260 000	2 520 000	6 300 000
Contingencies	176 983	344 822	687 165	1 592 214
TOTAL	1 538 391	2 997 299	5 973 047	13 840 017
NET INCOME	141 609	362 701	746 953	2 959 983
Per Cage	2 832	3 627	3 735	5 920
Per Kg	1.69	2.16	2.22	3.52

¹ Does not include family labour.

Table 8.
Capital Investments in Pure Cage Culture
	ITEM	2.5	5.0	10	25
A.	BARRIERS
	Materials	34 656	49 756	70 000	113 584
	Labour:
	Framework	6 004	8 568	12 032	19 040
	Stitching	640	912	1 280	2 025
	Sub-total A	41 504	59 056	83 312	134 649
B.	CAGES	50	100	200	500
	Materials at 4 000/cage	200 000	400 000	800 000	2 000 000
	Labour at 640/cage	32 000	64 000	128 000	320 000
	Sub-total B	232 000	464 000	928 000	2 320 000
	TOTAL (A & B)	273 504	523 056	1 011 312	2 454 649

Table 9.
Tilapia Production in Pure Cage Culture
ITEM	2.5 ha (50 cages)	5.0 ha (100 cages)	10 ha (200 cages)	25 ha (500 cages)
WITHOUT FEEDING
SUMMER CROP (150 g)
720 kg/cage	36 000	72 000	144 000	360 000
at 10/kg	360 000	720 000	1 440 000	3 600 000
COLD MONTHS CROP (200 g)
960 kg/cage	48 000	96 000	192 000	480 000
at 10/kg	480 000	960 000	1 920 000	4 800 000
TOTAL PRODUCTION	84 000	168 000	336 000	840 000
TOTAL VALUE	840 000	1 680 000	3 360 000	8 400 000
WITH FEEDING
SUMMER CROP (150 g)
1440 kg/cage	72 000	144 000	288 000	720 000
at 10/kg	720 000	1 440 000	2 880 000	7 200 000
COLD MONTHS CROP (20 g)
1960 kg/cage	96 000	192 000	384 000	980 000
at 10/kg	960 000	1 920 000	3 840 000	9 800 000
TOTAL PRODUCTION	168 000	336 000	672 000	1 700 000
TOTAL VALUE	1 680 000	3 360 000	6 720 000	17 000 000

Table 10.
Amount and Use of Loan in Pure Cage Culture
ITEM	2.5 (50 cages)	5.0 (100 cages)	10 (200 cages)	25 (500 cages)
Barriers and cages	273 504	523 056	1 011 312	2 454 649
Fingerlings	90 000	180 000	360 000	900 000
Repairs & Maintenance	27 350	52 306	101 131	245 464
Feeds	630 000	1 260 000	2 520 000	2 520 000
Total without Feeds	390 854	755 362	1 472 443	3 600 113
Total with Feeds	1 020 854	2 015 362	3 992 443	6 120 113

Table 11.
Loan Amortization Schedule (Without Feeds)
YEAR	Unpaid Balance Beginning of Year	Interest	Principal	Total Payment
390 000 (2.5 ha - 50 cages)
1	390 000	62 400	-	62 400
2	390 000	62 400	76 986	139 386
3	313 014	50 082.24	89 303.76	139 386
4	223 710.24	35 793.64	103 592.36	139 386
5	120 117.88	19 218.86	120 167.14	139 386
	TOTAL	229 894.74	390 049.26	619 944
755 000 (5.0 ha - 100 cages)
1	755 000	120 800	-	120 800
2	755 000	120 800	149 037	269 837
3	605 963	96 954	172 883	269 837
4	433 080	69 293	200 544	269 837
5	232 536	37 206	232 631	269 837
	TOTAL	445 053	755 095	1 200 148
1 473 000 (10 ha - 200 cages)
1	1 473 000	235 680	-	235 680
2	1 473 000	235 680	290 770	526 450
3	1 182 230	189 157	337 293	526 450
4	844 937	135 190	391 260	526 450
5	453 677	72 588	453 862	526 450
	TOTAL	868 295	1 473 185	2 341 480
3 600 113 (25 ha - 500 cages)
1	3 6000 113	576 018	-	576 018
2	3 600 113	576 018	710 662	1 286 680
3	2 889 451	462 312	824 368	1 286 680
4	2 065 083	330 413	956 267	1 286 680
5	1 108 816	177 411	1 109 269	1 286 680
TOTAL		2 122 172	3 600 566	5 722 738

Table 12.
Loan Amortization Schedule (With Feeds)
Year	Unpaid Balance Beginning of Year	Interest	Principal	Total Payment
1 020 000 (2.5 – 50 cages)
1	1 020 000	163 200	-	163 200
2	1 020 000	163 200	201 348	364 548
3	818 652	130 984	233 564	364 548
4	585 088	93 614	270 934	364 548
5	314 154	50 265	314 283	364 548
	TOTAL	601 263	1 020 129	1 621 392
2 015 000(5.0 – 100 cages)
1	2 015 000	322 400	-	322 400
2	2 015 000	322 400	397 761	720 161
3	1 617 239	258 758	461 403	720 161
4	1 155 836	184 934	535 227	720 161
5	620 609	99 297	620 864	720 161
	TOTAL	1 187 789	2 015 255	3 203 044
3 992 000(10 ha - 200 cages)
1	3 992 000	638 720	-	638 720
2	3 992 000	638 720	788 021	1 426 741
3	3 203 979	512 637	914 104	1 426 741
4	2 289 875	366 380	1 060 361	1 426 741
5	1 229 514	196 722	1 230 019	1 426 741
	TOTAL	2 353 179	3 992 505	6 345 684
6 120 113 (25 ha - 500 cages)
1	6 120 113	979 218	-	979 218
2	6 120 113	979 218	1 208 110	2 187 328
3	4 912 003	785 920	1 401 408	2 187 328
4	3 510 595	560 695	1 625 633	2 187 328
5	1 884 962	301 594	1 885 734	2 187 328
	TOTAL	3 607 645	6 120 885	9 728 530