The seasonality and economic feasibility of cultivating Kappaphycus alvarezii in Panagatan Cays, Caluya, Antique, Philippines

Aquaculture 199 Ž2001. 295–310 www.elsevier.nlrlocateraqua-online

The seasonality and economic feasibility of cultivating Kappaphycus alÕarezii in Panagatan Cays, Caluya, Antique, Philippines Anicia Q. Hurtado a,) , Renato F. Agbayani a , Roman Sanares b, Ma. Teresa R. de Castro-Mallare a a

Aquaculture Department, Southeast Asian Fisheries DeÕelopment Center, 5021 Tigbauan, Iloilo, Philippines Institute of Aquaculture, College of Fisheries, UniÕersity of the Philippines in the Visayas, 5023 Miag-ao, Iloilo, Philippines

b

Received 14 November 1999; received in revised form 2 May 2000; accepted 17 October 2000

Abstract Vegetative thalli of brown and green Kappaphycus alÕarezii were cultivated in Panagatan Cays, Caluya, Antique, Philippines, over 60- and 90-day periods using hanging-long line ŽHL., fixed off-bottom ŽFB., and hanging long line–fixed off-bottom ŽHL–FB. methods to determine the daily growth rate and yield. A completely randomized design experiment with six replicates of 5-m line cultivation rope was used in the study. An economic analysis was prepared to determine the viability of the culture systems used. To determine the effect of strain, culture technique, culture days and culture month on the daily growth rate and yield, a combination of these different factors was treated as a single treatment. Results show that at 60-day culture period, daily growth rate and yield in all techniques were lowest in July–August and highest in January–February. Higher growth rate Ž2.3–4.2% dayy1 . and yield Ž3.6–15.8 fresh weight kg my1 liney1 . were obtained from September to February. Significant differences Ž P - 0.05. in growth rate and yield were determined between culture months. At 90-day culture period, there were no significant differences in growth rate and yield between culture months; however, a significant difference was found between culture techniques. The average production Ždry weight kg cropy1 . of K. alÕarezii when grown at 60-day culture period during lean and peak months using HL, FB and HL–FB techniques ranged from 421 to 3310 kg with HL–FB the highest and FB the lowest. Net income, return on investment ŽROI. and payback period were all positive during peak months, but negative values were obtained during lean months. Only seaweed grown on HL technique during the peak

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Corresponding author. Tel.: q63-33-335-1009, 336-2965, 336-2937; fax: q63-33-335-1008. E-mail address: [email protected] ŽA.Q. Hurtado..

0044-8486r01r$ - see front matter q 2001 Elsevier Science B.V. All rights reserved. PII: S 0 0 4 4 - 8 4 8 6 Ž 0 0 . 0 0 5 5 3 - 6

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months at 90-day culture period showed positive income, ROI and payback period. The seasonality of cultivating K. alÕarezii is shown in this present study. This paper further shows the best culture technique to be adopted at certain months of the year to produce the highest yield and income. q 2001 Elsevier Science B.V. All rights reserved. Keywords: Kappaphycus alÕarezii; Cultivation techniques; Seasonality; Economics

1. Introduction Seaweed mariculture in the Philippines ranks number one in terms of amount of production among the marine-based products, and it is one of the top three export commodities, thus contributing large source of revenue to the country ŽDA-BFAR 1999.. Kappaphycus farming in the Philippines is nearly synonymous with the seaweed industry of the country since 85–90% is dominated by farming, processing, and marketing of this seaweed. The earliest reports on Kappaphycus farming in the Philippines were recorded by Doty Ž1973., Doty and Alvarez Ž1975. and Parker Ž1974.. Farming this seaweed has undergone many modifications since it was first introduced in Sulu, Mindanao, in 1967. It has expanded to other regions of the Philippines and also to other countries like Indonesia ŽAdnan and Porse, 1987; Luxton, 1993., Fiji ŽLuxton et al., 1987. and South Africa ŽBraud and Perez, 1978; Lirasan and Twide, 1993.. Earlier reports have also shown that experimental cultivation of this seaweed has been successful in Madagascar ŽMollion and Braud, 1993., Vietnam ŽOhno et al., 1996., and China ŽWu et al., 1989; Qian et al., 1996.. The economic viability and feasibility of Kappaphycus farming ŽSamonte et al., 1993; Alih, 1990; Firdausy and Tisdell, 1991. has improved the socio-economic conditions of coastal families ŽSmith and Pestano-Smith, 1980; ˜ Hurtado-Ponce et al., 1996.. The estimated monthly requirement of Philippine seaweed exporters and processor is 102 000 t dry weight Ždwt., but the country has an estimated production of only 96 000 t dwt ŽCambonga, unpublished data. which indicates that increased production is needed. The production of Kappaphycus alÕarezii in the Philippines comes mainly from southern Mindanao Ž80%. and the rest from the Visayas and Luzon ŽPorse, unpublished data.. Western Visayas is an emerging key production area in the country and most of this production comes from Caluya, Antique ŽSamonte et al., 1993; Hurtado-Ponce et al., 1996.. Although an earlier report showed that Eucheuma farming started in Panagatan Atoll, Caluya, Antique in 1969 ŽDoty, 1973., it was only in the late 1980s and early 1990s that extensive farming of K. alÕarezii was done ŽHurtado-Ponce et al., 1996.. Despite the success of Kappaphycus farming in the Philippines and elsewhere, there is no report on the year-round farming of the commercial strains using different culture techniques with an analysis of economics for the Western Visayas region. This study reports on the seasonality of K. alÕarezii using strains, culture techniques and culture days as factors in assessing growth rate, yield and its economic feasibility.

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2. Materials and methods The study was conducted in Panagatan Cays, Caluya, Antique ŽFig. 1.. Two strains Žbrown and green. ŽTrono, 1993. of K. alÕarezii were purchased from local fisherman and used in the study. The usual methods of preparing and installing the transplants were

Fig. 1. Map of the experimental site, Panagatan Cays, Caluya, Antique, Philippines.

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followed ŽDoty, 1973; Samonte et al., 1993; Hurtado-Ponce et al., 1996. using a 5-m cultivation line Ža7 polyethylene rope. containing 2 kg transplants liney1 . Three sets of culture techniques were tested: Ž1. hanging long-line ŽHL., Ž2. fixed off-bottom long line ŽFB., and Ž3. a combination of the two techniques ŽHL–FB.. For the combined technique ŽHL–FB., seaweeds were grown using the hanging long line technique for the first 30 days; then the lines later were brought down to a depth between the lowest and highest tide level for the next 30 or 60 days. The seaweeds were harvested at 60- and 90-day intervals in order to determine daily growth rate ŽDGR s % dayy1 . which was calculated using a formula that takes into account exponential growth as shown for other field studies ŽDawes et al., 1993. DGR Ž % . s ln Ž WfrW0 . rt = 100 where Wf is the final fresh weight Žkg. at t day, W0 is the initial fresh weight Žkg., t is the number of culture days. Plant yield Ž Y ., expressed as mean Žkg. my1 liney1 was also determined using a modified formula of Doty Ž1986. to include the initial weight of the transplants Y s Ž Wf y W0 . rLt where Wf is the final fresh weight Žkg., W0 is the initial fresh weight Žkg., Lt is the total length Žm. of lines harvested. Six culture months ŽMay–June, July–August, September–October, November–December, January–February and March–April. were used for the 60 day culture period and four culture months ŽMay–July, August–October, November–January and February–April. for the 90-day culture period to complete a 1-year study. Young thalli were selected from every harvest and served as new transplants for the next run. The study was originally conducted using a factorial experiment in Completely Randomized Design ŽCRD. to determine the effect of strain, culture technique, culture period and time of the year on daily growth rate and yield of seaweeds. However, because of missing values, one-way ANOVA was utilized using combinations of different factors for treatments. Missing replicates were washed-out during a typhoon before the harvest. Individual statistical analysis was made for 60- and 90-day culture periods. Thirty-six treatments using combinations of two strains, three culture techniques and six culture months were used in 60-day culture period and 24 treatments using combinations of two strains, three culture techniques and four culture months in the 90-day culture period. Each treatment had originally six replicates. The average production of the culture systems was estimated in t dwt hay1 cropy1 at 7:1 freshrdry weight ratio ŽSIAP, unpublished data.. The investment requirements include the capital assets such as non-motorized boat, monoline ropes and floats, while working capital included inputs such as seedlings, hired labor, and materials. The computation of the cost and returns analysis was made in 60 and 90 days culture periods based on extrapolating 30 m2 to a 1-ha area. Values were based from the average yield obtained during the peak and lean months of each culture technique. Revenue obtained from the yield was computed based from the prevailing

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Table 1 Delivered price kgy1 in Philippine peso of dried seaweed to the processor from 1995 to 2000 Month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Year 1995

1996

1997

1998

1999

2000

15.5–16.00 17.00–18.00 14.00 16.50 16.00 16.00 15.00 15.00 16.50 16.50 16.00 16.00

16.50 26.50 18.50 19.50 19.50 21.00 19.50 19.50 19.00 18.50 19.00 19.00

21.00 21.00 21.00 21.00 21.50 21.00 21.50 21.00 21.00 21.50 21.00 21.00

20.00 19.50 20.00 20.00 20.00 20.00 20.50 21.50 24.00 24.50 26.00 28.00

27.00 27.00 26.00 26.00 25.00 26.00 26.00 26.00 26.00 27.50 27.50 26.50

26.00 25.00 24.50 24.50 24.50 24.00 24.00 24.00

MCPI, personal communication.

ex-farm price ŽPhP 7.50 kgy1 . for both strains since there is no price difference between the two strains ŽMCPI, personal communication.. The farm-gate price is about 50% of prices when delivered directly to exporters or processors, which was about PhP 14–18 kgy1 ŽTable 1.. The difference in the prices represents the cost of packing, handling, and transporting the seaweed plus the mark-up of the middlemen. The economic indicators are return on investment ŽROI. and payback period.

3. Results 3.1. Growth rate and yield The average growth rate ŽFig. 2a. and yield ŽFig. 2b. of brown K. alÕarezii showed the same pattern as the green strain at 60-day period. The brown strain during the culture months from September to February Žpeak months. of the following year generally seemed to show higher growth rates Ž0.2–4.2%. than the green strain Ž0.9–3.9%. in all culture techniques. However, differences were not significant at P ) 0.05. The green strain generally showed higher growth rate on the culture months from May to August but with also no significant difference with brown strain. Both strains had their lowest growth rates and yields from July to August Ž‘lean’ months. which is significantly lower Ž P - 0.01. than the months of November–February. Comparable growths and yield were obtained in both strains from September to February in all culture techniques. Both strains registered the highest daily growth rate Ž3.9–4.2%. and yield Ž12.0–15.8 fwt kg my1 liney1 . in January–February using the HL–FB technique. Over 90-day culture periods, growth rates ŽFig. 3a. and yield ŽFig. 3b. of both strains were lowest using the FB method in May–July and February–April, respectively. Both strains showed highest growth rate in HL in all culture months but not significantly

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different from HL–FB except in February–April. No data were obtained from November–January because the seaweeds were washed-out due to a typhoon. 3.2. EnÕironmental parameters The average monthly salinity readings ranged from 32‰ to 35‰; surface and bottom water temperature ranged from 288C to 318C ŽFig. 4.. The lowest salinity reading was recorded in July while the lowest water temperature both surface and bottom was recorded in January. There was little variation in temperature readings in surface and bottom from January to July but from August to December temperature readings were identical.

Fig. 2. Ža. Average daily growth rate Ž% dayy1 . of brown and green strains of K. alÕarezii over a 60-day culture period. Žb. Average yield Žfwt kg my1 liney1 . of brown and green strains of K. alÕarezi over a 60-day culture period.

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301

Fig. 2 Ž continued ..

3.3. Economics On a per hectare basis, investing in the fixed off-bottom ŽPhP 14 150. is less expensive than hanging long-line ŽPhP 17 900. or the combination of the two methods ŽPhP 17 900. ŽTable 2.. This is because there is no need to use floats in the fixed off-bottom technique. The cost breakdown ŽFig. 5. shows labor as the highest cost component Ž40%. followed by capital outlay Ž22%., materials Ž21%., seedlings Ž12%. and interest expense Ž5%.. The average quantity Ždwt kg cropy1 . and corresponding revenue ŽPhP. obtained during the lean and peak months in a 60-day culture period ranged from 421 to 3310 and 18 964 to 148 929, respectively ŽTable 3.. Both were highest in HL–FB, followed by HL and lastly the FB technique. A negative net income ŽPhP y2 709 to y11 884. was obtained during the lean months in all techniques; however, a positive net income ŽPhP 60 759 to 113 756. was obtained during the peak months in all culture techniques. Consequently, the ROI resulted in negative values during the lean months Žy15% to y84%. while positive ROI was obtained during the peak months Ž429–636%. in all

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culture techniques. Except for the seaweed grown at HL during the peak months in a 90-day culture period, net income, ROI and payback period were all negative ŽTable 4..

4. Discussion Both strains Žbrown and green. of K. alÕarezii showed high growth rates Ž3.9–4.2% dayy1 . similar to the results obtained by others ŽDawes et al., 1994; Ohno et al., 1996.. A higher yield was obtained in HL than in FB in the present whereas opposite results were reported by Hurtado-Ponce et al. Ž1996. in the same cultivation area. The following may explain the difference: Ž1. the latter report was based on a survey that relied mainly on interviews with fisherfolk, thus the values given were just estimates and do not reflect the actual harvest, and Ž2. the culture technique in the present study was an improvement from the earlier report, since the seaweeds were maintained 25–30 cm below the water surface, completely submerged, and not exposed to air, strong wave action and intense sunlight. The fisherfolk, as reported by Hurtado-Ponce et al. Ž1996.,

Fig. 3. Ža. Average daily growth rate Ž% dayy1 . of brown and green strains of K. alÕarezi over a 90-day culture period. Žb. Average yield Žfwt kg my1 liney1 . of brown and green strains of K. alÕarezii over a 90-day.

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303

Fig. 3 Ž continued ..

tied the seaweeds on the same plane as the styrofoam floats thereby exposing them to elements. Highest standing crops of Kappaphycus and Eucheuma in nature are often found in areas with stable sunlight, water motion, water quality and temperature ŽDoty, 1973.. On the other hand, a lower yield was obtained in FB in the present study compared with the report of Hurtado-Ponce et al., 1996. The difference can be attributed to the excessive grazing of siganids and sea urchins as well as the presence of non-epiphytic ‘fouling’ seaweeds like Enteromorpha, UlÕa, Hypnea, Dictyota, and Hydroclathrus, which compete directly with K. alÕarezii for space on cultivation rope and removal of nutrients and inorganic carbon from the water column ŽBuschmann and Gomez, 1993.. As a consequence, the shading effect of these ‘fouling’ seaweeds is detrimental to K. alÕarezii ŽKuschel and Buschmann, 1991. resulting in yield reduction. As expected, growth rate and yield during the months of July–August Žsouthwest monsoon. were minimal mainly due to the prevailing environmental conditions, characterized by strong wave action, lower temperature and lower salinity brought by monsoon rains ŽHurtado-Ponce, 1990.. Among the three methods used in the present study, the combination of HL and FB seemed to be more appropriate during these months since the seaweeds were brought down to the mid-bottom of the highest tide after 30 days of culture, thus exposing them to a compromised light intensity level ŽDoty, 1973. and

304

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Fig. 4. Average surface and bottom water temperature and salinity readings in the cultivation area.

keeping them from excessive exposure to strong waves and low salinity during rainy days. The growth of both strains cultured on an FB method is comparable with the results obtained in Eucheuma cottonii by Adnan and Porse Ž1987. and Mollion and Braud Ž1993. at 2.5–3.5% and 3–4%, respectively; however, the present results were slightly lower than the results of Luxton et al. Ž1987. at 3.5–3.7%. Growth rate of both strains using HL and HL–FB from September to February at 60-day period were above 2% dayy1 , indicating its commercial potential as reported by Doty Ž1987.. Yield recorded in the present study when compared with Tawi-Tawi, Sulu, production shows an opposite trend. The latter shows a higher production during the southwest monsoon ŽHurtado-Ponce, unpublished data. and this is primarily due to calm sea, very occasional rainfall and rare storms in the area. The bottom type of loosely cultivating K. alÕarezii in pens in Hawaii ŽGlenn and Doty, 1990. showed higher yield Ž21 t dwt hay1 yeary1 . than when cultured in fixed off-bottom type in the present study using the brown and green strains at 60 Ž5–11 t dwt hay1 yeary1 . and 90 Ž1.3–4.5 t dwt hay1 yeary1 . days culture period. The sustainability of a farming industry depends largely on the proper use of culture technique and an appropriate strain at the right culture months. Apparently, the

Culture techniques Fixed off-bottom ŽFB.

ŽA. Capital investment Non-motorized boat Monoline rope Float Sub-total ŽB. Working capital ŽC. Total investment a

Hanging long line ŽHL.

Hanging long line– Fixed off-bottom ŽHL–FB.

Value

Economic life

Depreciationa

Value

Economic life

Depreciationa

Value

Economic life

Depreciationa

2500 5000 0 7500 6650 14 150

5 4 0

500 1250 0 1750 7150 17 900

2500 7500 750 10 750 7150 17 900

5 4 3

500 1875 250 2625

2500 7500 750 10 750 7150 17 900

5 4 3

500 1875 250 2625

Straight-line method ŽShang, 1990..

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Table 2 Investment requirements of the different culture techniques of K. alÕarezii using two strains Ždata combined. in Panagatan Cays, Caluya, Antique Ž1 US$s PhP 39.

305

306 A.Q. Hurtado et al.r Aquaculture 199 (2001) 295–310

Fig. 5. Cost breakdown in the cultivation of K. alÕarezii.

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307

Table 3 Average costs and returns analysis in the different culture technqiues of K. alÕarezii during lean and peak months of the 60-day culture period Culture techniques FB

HL

Lean months Yield Ždwt kg, cropy1 . Revenues ŽPhP, 6 crops yry1 . Operating expenses Cash Seedlings Labor Tying of seedlings Installation Soft Atie –tieB Post Interest expense Ž12% of investments. Sub-total Non-cash Family labor harvestingrdrying Depreciation Sub-total Total cost runy1 Total cost yeary1 Ž6 runs. Net income before tax Return on investment ŽROI. Payback period Žyears.

HL–FB

Peak months

Lean months

Peak months

Lean months

Peak months

421 18 964

2036 91 607

719 32 357

3029 136 286

723 32 539

3310 148 929

4000

4000

4000

4000

4000

4000

500 1000 900 250 283

500 1000 900 250 283

500 1500 900 250 358

500 1500 900 250 358

500 1500 900 250 358

500 1500 900 250 358

6933

6933

7508

7508

7508

7508

1250 438 1688 9196 35 173 y2816 y16% y93.79

1250 438 1688 9196 35 173 101 113 565% 0.17

1250 438 1688 9196 35 173 y2634 y15% y2054.1

1250 438 1688 9196 35 173 113 756 636% 0.15

1250 292 1542 8475 30 848 y11 884 y84% y1.40

1250 292 1542 8475 30 848 60 759 429% 0.23

FB, fixed off-bottom; HL, hanging long line.

combination of an HL–FB technique in a 60-day culture period is the best technique during the peak months because it resulted in the highest net income and ROI and the lowest payback period, suggesting a high profitability compared to HL and FB. The negative values obtained as net income and ROI in the present study when K. alÕarezii was cultured at 60 days in all techniques suggest the unprofitability of seaweed farming during the lean months. Probably, the farming of seaweed at this period is more for the sourcing of transplants rather than for biomass production. The combined culture technique ŽHL–FB. is an improvement of the present practice of fisherfolk using a single technique of either a fixed off-bottom or hanging long-line. Seaweed farming is labor intensive, making it an appropriate livelihood among coastal fisherfolk. It has generated cash income for ) 1500 fishing families in Indonesia ŽAdnan and Porse, 1987., ) 80 000 families in the Philippines ŽTrono, 2000. and ) 400 people in the Republic of Kiribati ŽLuxton and Luxton, 1999.. Collective or cooperative farming among fisherfolk is highly recommended in order to increase the total volume.

308

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Table 4 Average costs and returns analysis in the different culture technqiues of K. alÕarezii during lean and peak months over a 90-day culture period Culture techniques FB Lean months

HL Peak months

Lean months

Yield Ždwt kg, cropy1 . 0 426 517 Revenues ŽPhP, 6 crops yry1 . 0 19 179 23 250 Operating Expenses Cash Seedlings 4000 4000 4000 Labor Tying of seedlings 500 500 500 Installation 1000 1000 1500 Soft Atie –tieB 900 900 900 Post 250 250 250 Interest expense 283 283 358 Ž12% of investments. Sub-total 6933 6933 7508 Non-cash Family labor Harvestingrdrying 1250 1250 1250 Depreciation 292 292 438 Sub-total 1542 1542 1688 Total cost runy1 8475 8475 9196 Total cost yeary1 Ž6 runs. 30 848 30 848 35 173 Net income before tax y30 848 y11 669 y11 923 Return on investment ŽROI. y218% y82% y67% Payback period Žyears. y0.49 y1.43 y1.93

HL–FB Peak months

Lean months

Peak months

1686 75 857

0 0

500 22 500

4000

4000

4000

500 1500 900 250 358

500 1500 900 250 358

500 1500 900 250 358

7508

7508

7508

1250 1250 1250 438 438 438 1688 1688 1688 9196 9196 9196 35 173 35 173 35 173 40 684 y35 173 y12 673 227% y196% y71% 0.41 y0.5 y1.78

FB, fixed off-bottom; HL, hanging long line.

If volume is at least 5 t dwt, it is financially advantageous to deliver directly to the exporters or processors rather than selling through middlemen as experienced in the SEAFDEC CRM project in Culasi, Antique, Philippines ŽFAMI, personal communication.. The additional income derived from seaweed farming has dramatically improved the socio-economic conditions of the fishing families as earlier reported by Smith and Ž1980., Firdausy and Tisdell Ž1991. and Hurtado-Ponce et al. Ž1996.. The Pestano-Smith ˜ findings of this study validate the earlier report of Smith Ž1986. that indicated good profitability of small farms of 1 ha or less. To some extent, seaweed farming has successfully attracted families out of full-time fishing especially in small island communities in central Philippines. From a national standpoint, seaweed farming is a good investment because it is labor intensive and does not require imported inputs such fertilizers, chemicals and feeds. The present study shows a strong seasonality of culturing K. alÕarezii as demonstrated from the results obtained in growth rate, yield, net income, ROI and payback period during lean and peak months.

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309

Acknowledgements The authors are thankful to Ephraim Doroteo for his unwavering assistance in the field, Mr. and Mrs. Ador del Rosario for their collaborative effort and untiring support in the management of the seaweeds and in providing us a home during fieldwork, and Ms. Mila Castanos ˜ for editing the original manuscript.

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