PART II
LECTURE AND PRACTICAL EXERCISES(continue)

Lecture 6 and Practicum 7
INVENTORY AND ASSESSMENT OF ECONOMICALLY IMPORTANT SEAWEED STOCKS(continue)

7. DATA PROCESSING AND INTERPRETATION

Once the data are available, they should first be organized and systematized to facilitate the statistical procedures used in data analysis. It should be emphasized that it is only by means of statistical methods that: (a) characteristics of sets of data can be quantitatively described and summarized; (b) conclusions about large sets of data, using only samples of them can be drawn; and (c) relationships between sets of data established. Hence, in the present paper, simple statistical manipulations will be frequently encountered but for no other reason that the fact that a good ecological work requires them.

An understanding of some basic statistical concepts is needed at this point:

1. Statistical population — the entire set of data about which we wish to draw conclusions. (For example, a population of Gracilaria).

2. Statistical sample — a portion of the statistical population.

3. Parameter — in statistics, it is a measure that describes or characterizes an entire population of data. (For example, density or frequency of Caulerpa).

4. Statistics — descriptive measures derived from sample data taken from the population. (For example, mean and median).

7.1 Descriptive statistics

Although we cannot directly measure a parameter of a population, we can describe, for example, the density of a seaweed population by using the:

a) Mean — this is a measure of the central tendency of a population and is computed as:

X= ΣX/n

The sample mean is a reasonable estimate of the population mean only when the former is obtained at random from the entire population.

b) Median — this is the middle measurement in a ranked data. If there are an even number of data, the median is the mean of the two middle measurements.

c) Range — a measure of how variable the gathered data are, the range is simply the difference between the largest and the smallest measurement. The big disadvantage in using the range to describe dispersion of sample data is that it tends to underestimate the population range.

d) Standard deviation (s) — this is a mea sure of how the data are dispersed relative to the mean. For this reason, it becomes very useful in statistics:

e) Variance — this variance is:

s² = SS/DF

where: SS (“sum of squares”) =∑(X — X)²; DF (“degrees of freedom”) = n — 1

f) Standard error — we often ask the question: How precise is our estimated mean? If we have replicates of, for example, the cover of Caulerpa taken from a population, each sample will have a different mean and how the sample means vary from each other can be measured by the standard deviation of the mean or standard error (SE).

g) Confidence interval — with a known standard error, we can set a range, with a stated level of confidence, within which the population mean lies:

(1 — α)confidence interval for population mean,μ = X + SE

The value of t is obtained from a statistical distribution known as “Students' t”, a portion of which is given below:

DF	= 0.10	= 0.05	= 0.02	= 0.01
1	6.31	12.71	31.82	63.66
2	2.92	4.31	6.96	9.92
3	2.35	3.18	4.54	5.84
4	2.13	2.78	3.75	4.60
5	2.01	2.57	3.36	4.03
6	1.94	2.45	3.14	3.71
7	1.89	2.36	3.00	3.50
8	1.86	2.31	2.90	3.36
9	1.83	2.26	2.82	3.25
etc.	etc.	etc.	etc.	etc.

7.2 Selecting statistical sample size

In general, the greater the value of n = (number of data ion the sample), the smaller the amount of error and the more precise the estimate of the population mean. This is evident from the formula for SE above. From this relationship, we can determine the number of data (n) required to estimate the population mean with a specified precision.

7.3 Comparing statistical populations

Phycologists may often ask the question: Are the mean seaweed biomass of, for example, two apparently similar portions of the shore, the same? Are they the same in two different seasons? The community coefficients (CC_J and CC_S) discussed above give only the relative degree of similarity between the communities. They do not tell us whether that difference is a result of habitat — specific conditions or of other factors.

The more common tests to compare statistical populations are: two sample (or t-) testing, multisample testing (analysis of variance, ANOVA) and non-parametric testing.

The first two are applicable only in instances where the populations being compared have equal variances and each population is composed of data which conform to the “normal distribution”. For example, lengths, weights, heights and rates can be compared using t-testing and ANOVA. But percentages or proportions, densities, pH and other data measured on a non-linear scale should not be subjected to the above tests. Instead, they are analyzed using non-parametric or distribution-free methods.

7.4 Qualitative description of study site

This aspect of the study should be considered in terms of:

7.4.1. Location — specific municipality where it is located; describe in relation to major bay(s) in the vicinity; use bathymetric or topographic maps, with compass bearings;

7.4.2. General physiographic setting — reckon in terms of:

1. type of shoreline; general features of the reef

2. dominant substrate

3. in relation to major natural or artificial structures

4. dominant associated flora and fauna

5. major curent patterns; wave exposure

6. dominant associated activities of local inhabitants

7. specific disturbances of the habitat

7.5 Quantitative description and summarization of data

This portion of the study is to be done at both the station- (i.e., specific transect) and site- (i.e., considering all transects) levels.

7.5.1. Biological parameters

1. species composition

2. mean species relative frequency (RF%) for both seaweeds and seagrasses

   • specific or in relation to its community

   • general or in relation to both communities

3. mean species relative cover (RC%) for seaweeds and seagrasses

   • specific

   • general

4. mean species biomass (dry wt.: wet wt. difference, gm/m²) for both seaweeds and seagrasses

   • total per community
   • total for both communities

   • wet wt.: dry wt. ratios — for each species

5. species diversity

6. community similarity

7.5.2 Physico-chemical parameters

1. mean temperature (°C) per station, surface and bottom; overall mean for site (surface and bottom)

   • min-max thermometer reading

   • temperature profile

2. mean salinity (‰) per station; overall

   • salinity profile

3. mean dissolved oxygen (mg/l) per station; overall

   • DO profile

4. mean light intensity ( μE mol-¹ sec-¹) per station; overall

   • light intensity profile

5. bottom type and contour per station; overall

7.6 Objective assessment of differences and relationships of the sets of data

This aspect of the study would primarily deal with:

1. correlation and regression
2. satistical tests

3. graphical presentations (i.e., histogram, curves, 3-dimensional structures, pie-diagrams, matrices, etc.).

7.7 Drawing conclusion from the data

This aspect of the study is almost solely dependent on the experience and knowledge-ability of the worker. Relevant information available from the literature and data obtained from measurements of environmental variables are very useful at this point. But they are so only to the extent of supporting and/or supplementing the primary findings just obtained from the study. So long as the interpretation of results and the conclusions drawn from the data have conformed to the steps outlined above, in a form that is easily comprehensible, and they answer the basic questions posed before the survey was conducted, it is fairly reasonable to assume that a “good job” is almost done.

The important questions to answer at this point include:

7.7.1. Basic considerations

1. Which species or species group was dominant? Least dominant?

2. What do the trends in the parameters suggest?

3. Which physico-chemical factors had apparent control over the observed trends?

4. Were there indications of species/community interactions (positive or negative)?

7.7.2. Management considerations

1. Which species or species group had the best potential for culture or intensive study?

2. If the study were carried monthly through a year's duration.

3. What could be the most important issues in the conservation and optimum utilization of the seaweed resources at the site?

4. What are the major problems and limitations?

CONCLUSIONS

To monitor a parameter that controls the development of seaweeds, whether it be in the field or in the laboratory is to regularly gather, determine and record changes in that parameter through time and space. The process becomes impractical and untenable when too many factors are considered. Hence, only the operationally significant factors should be included in the monitoring process. Factor-monitoring could be species and/or site-specific.

A serious consideration of technical, logistical and administrative support should be made before any attempt to monitoring is undertaken. The failure of many research projects lies in their being poorly conceived, often the monitoring component is so defective, or management is not outwardly supportive of the project objectives. The lack of government emphasis on seaweed research evidenced by the lack of equipment, library facilities and personnel incentives, remains as a primary obstacle to the development of the seaweed industry in the Asia-Pacific.

REFERENCES

Doty, M.S. 1946 Critical tide factors that are correlated with the vertical distribution of marine algae and other organisms along the Pacific coast. Ecology. 27:315–328.

Fortes, M.D. 1981 Community structure and productivity of microphytic algae from Philippine reefs. Proc. 4th Int. Coral Reef Symp. Manila. 2: 393–398.

Kinne, O. (ed.) 1970 Marine ecology: A comprehensive integrated treatise on life in oceans and coastal waters. Vol. 1.Environmental factors.

Odoum, E.P. 1971 Fundamentals of ecology. 3rd ed. W.B. Saunders Company, Pa. 574 pp.

Saito, Y. and S. Atobe. 1970 Phytosociological study of intertidal marine algae. I Usujiri Benten-Jima, Hokkaido, Bull.Fac. Fish. Hokkaido Univ. 21(2): 37–69.

Lecture 7
THE TAXONOMY OF COMMERCIALLY IMPORTANT SEAWEEDS IN THE PHILIPPINES AND TROPICAL ASIAN-PACIFIC REGION

by

Gavino C. Trono, Jr.¹

1. INTRODUCTION

The utilization of seaweeds as items of food and as raw materials for industries highlights the economic importance and potentials of these fishery resources. The increasing contributions of the seaweed industry to the foreign trade as well as the utilization of a number of species as food in some Asian countries have emphasized the need to develop the large but untapped potentials of these resources in the region.

In the Philippines, seaweed and seaweed products have gained prominence as the number three fishery export behind shrimps and tuna during the last five years. More-over, seaweed farming and/or gathering of natural stocks have become a productive alternative or additional source of livelihood among the coastal populations who are not at all benefited by industrial developments. The relevance of the seaweed resources to the economic welfare of the artisanal fisher-men and their families has been emphasized recently because of the degraded conditions of many of the shallow coastal fishing areas in the country. At present, thousands of fishermen and their families in Tawi-tawi, Sulu and Central Visayas are gainfully engaged in the farming of seaweeds. Seaweed farming has become a major industry in these places.

One of the basic problems which prevents the rapid development of the seaweed resources in the Philippines and in the other developing countries in the tropics is the lack of information on the identities of economically important species of seaweeds. The taxonomy of seaweed species has been identified as “the greatest single obstacle in the progress of seaweed aquaculture and marine natural products chemistry in the Pacific. Taxonomy is the hidden, natural products chemistry in the Pacific. Taxonomy is the hidden, but important foundation of the superstructure of aquaculture and mariculture, whether of mollusks, crustaceans, fish or seaweeds...” (Sullivan, 1985).

The taxonomy of seaweeds of commercial value is in many cases not known. The correct scientific names attached to commercial species are tremendously important because the quality of the phycocolloids derived from them are so divergent, i.e., the gel properties are very different depending on the species. The prices, for instance, of local species of agarophytes differ significantly because of the differences in the agar quality they contain. Buyers/processors need to know the kind and quality of the product they are buying, e.g., Gelidiella acerosa commands a price many times higher than Gracilaria “verrucosa” because of the better gel it contains. The correct name attached to a seaweed is thus, very important because it provides the clue to the identity of the species which is used as basis for determining the value of the product.

2. THE TAXONOMY OF THE COMMERCIALLY IMPORTANT SEAWEEDS IN THE PHILIPPINES

2.1 The Philippine agarophytes

The agarophytes are agar-producing sea-weeds which belong mainly to several genera in the Rhodophyta. Included in this group are the genera-Gracilaria, Gelidiella, Beckerella, Laurencia, Gelidium and Pterocladia. Of these genera Gracilaria and Gelidiella are commercially utilized. The other genera are not economically utilized for various reasons, e.g., Beckerella although has great potential because of its large size is not a common species; Laurencia is common and appear to have large naturally produced biomass but except probably for one species, the quality of the agars of the several large species are not known and thus, have not been commercially utilized; Gelidium and Pterocladia although well known for their good quality agars, their representative species are too small for commercial utilization. In addition to these genera, there are probably other species which are not yet known.

These genera are also found in the tropical Asia and Western Pacific countries.

2.1.1 The genus Gracilaria

The genus Gracilaria belongs to the Family Gracilariaceae, Order Gigartinales. This genus is fairly well known in the Philippines. Abbott (1985) listed some 17 species based on records available (refer to Annex A). However, except for seven species namely, G. arcuata, G. “verrucosa” the identities of the other species have to be verified. It would appear, however, that several of these binomials are names which have been misapplied to these taxa.

The genus Gracilaria is characterized by plants that generally have fleshy and succulent, and in one species cartilaginous thalli which consist of a holdfast, and cylindrical to compressed or foliose branches. The thallus grows by means of a group of apical cells and is multiaxial in construction. The thallus is basically filamentous but the filaments become compacted to form pseudo-parenchymatous tissue. The tetrasporangia are cruciate and occur generally in the cortex of the mature thallus.

The gametophytes are dioecious. The female thallus when reproductive forms a fertile structure called the cystocarp. The fertile male thallus produces the spermatangia in cavities called the conceptacles. The conceptacles are mainly limited to the outer cortex and may be one of general forms, namely, pot-shaped, cup-shaped and saucer-shaped. In first type the cavity is deep with a narrow opening; in the second the opening has the same diameter as the diameter of the conceptacle while in the last type, the conceptacle is shallow. Although the male plants are not commonly collected, the type of conceptacle it possesses is diagnostic of the species and so these are very important.

The key and descriptions of the eight species of Gracilaria are contained in the paper by Trono, Azanza-Corrales and Manuel (1983), a copy of which is appended. Reports of other species are found in the literature but I feel that these need verification.

2.1.2 The genera Gelidium, Pterocladia, Beckerella and Gelidiella

These are genera under the Order Gelidiales. The first three belong to the Family Gelidiaceae and the last to the Family Gelidiellaceae. These are characterized by generally tough and wiry thalli (dried) with a distinct apical cell at the tip of the branch.

2.1.3 The genus Gelidiella

The genus Gelidiella is represented by several species but except for G. acerosa, these are small and thus, are not utilized in the manufacture of agar. Only G. acerosa is presently harvested from natural stocks for agar processing.

The thallus of G. acerosa consists of cylindrical stolon from which erect and decumbent branches arise. The branches are cylindrical and bear pinnately arranged determinate branchlets. In fertile materials, tetrasporangial stichidia are borne near the tips of the determinate laterals. No gametophytes are known. This species is pantropic and therefore found in most tropical countries.

Other species of Gelidiella which have been reported in the Philippines are:

1. G. myriocladia — Tuft forming habit, erect branched well-branched; very small — 1–1/2 cm tall.

2. G. tenuissima — With creeping stolon attached by small hapters at regular intervals.

3. G. adnata — With creeping stolon attached by rhizoids along the entire ventral side of the stolon. Erect branches simple. Tetrasporangial stichidia stalked from the stolon.

2.1.4 The genus Gelidium

The Philippine Gelidiums are not well known taxonomically. There are, however, reports of four common species in the Western Pacific area and the South China Sea region. But undoubtedly these species are also present in the Philippines and other countries in tropical Asia and Western Pacific Region.

1. G. crinale — Small species like the other three below but is quite distinctive from them that the branches are mainly cylindrical to subcylindrical in contrast to other which have compressed to flattened branches.

2. G. pussilum — Branches compressed to flat; turf forming.

3. G. divaricatum — Branches compressed to flat; not forming turf, the main branches broader than the laterals.

4. G. puchellum — Branches compressed to flat, not forming tuft, main branches and laterals same in width.

2.1.5 The genus Pterocladia

Like Gelidium this genus is not well known taxonomically in the Philippines. So far very few unreliable reports are available in the literature. The reports are based mainly on the morphology of the materials. The similarity between this genus and Gelidium has been emphasized, i.e., these two are morphologically very similar. The distinction lies mainly on the structure of the cystocarp, e.g., Pterocladia has a unilocular cystocarp while in Gelidium it is bilocular. Thus, reports on the species of Pterocladia which do not include the information on the type of cystocarp are always doubtful.

2.1.6 The genus Beckerella

Only one species of Beckerella, B. scalaramosa has been reported in the Philippines. The thallus consists of stoloniferous axis from which erect branches arise. The main branches are flattened/compressed and percurrent. Branching is pinnate. This species has only been reported from Bulusan, Sorsogon, Southern Luzon growing on the coralline wall of deep tide pools.

2.1.7 The genus Laurencia

The genus Laurencia is one of the more common components of seaweed communities on reefs in tropical areas. The genus is easily recognized by the form of its determinate branchlets which are generally clavate in shape with a single pit at the tip from where tufts of uniseriate hairs called Arichoblasts arise.

Although the genus is taxonomically relatively well known in the Philippines, this is not at present being utilized as raw materials for the manufacture of agar because the quality of the colloids is not known. Among the many species, only L flexilis has been reported as possessing good quality agar.

The paper of Saito (1969) is a major paper which covers the taxonomy of the genus in the Philippines, a copy of which is appended. Among the species which have been reported here are L cartilaginea, L flexilis, L japonica, L majuscula, L marianensis, L obtusa, L. papillosa, L parvipapillata, L subsimplex and L. tronoi.

2.2 The carrageenophytes

The carrageenophytes are carrageenan-producing seaweeds. The genera Eucheuma and Hypnea are two important genera of carrageenophytes which are abundant in the Philippines and in the tropical Asia and Western Pacific, More recently Acanthophora spicifera has been reported to contain lamba carrageenin which is not produced by either Eucheuma or Hypnea. At present, the most important of the many genera of carrageenophyte is Eucheuma which is at present the main base of the seaweed industry in the Philippines and Indonesia, although the latter is producing only a few thousand tons of this seaweed recently. The development of the culture technology for this genus has boosted tremendously production in the Philippines to an estimated 60 000 MT in 1987.

2.2.1 The genus Eucheuma

The genus Eucheuma belongs to the Family Solieriaceae of the Order Gigartinales. Of the more than two dozen species known in the world, seven species of Eucheuma are present in the Philippines. These are E. denticulatum (£. spinosum), E. procrusteanum, E. cottonii, E. strialum, E. arnoldii, E. gelatinae and E. alvarezii. Eucheuma alvarezii and E. denticulatum are the species presently produced through mariculture in the Philippines and Indonesia. E. alvarezii and E. gelatinae are also cultured in Haman Island in China.

The thalli of Eucheuma are very cartilaginous, may be prostrate or erect in habit and consist of cylindrical to compressed branches except in one species whose thallus is a thick and flattened blade (£. procrusteanum). Gamophytic and sporophytic thalli have been reported for many species. Fertile female thalli develop distinct cystocarps which appear as mammillate structures. The male thalli, however, appear to be uncommon.

Brief descriptions of the species

1. E. alvarezii — Thallus erect, large; main axes percurrent or may be obscured by secondary axes; axes and branches cylindrical; branching open with rounded axils; diameter of branches larger at base and tapering towards the tip: axiferous, the medullary core of axial hyphae persistent to at least 10 cm below the tip of any indeterminate branch less than 5 mm in diameter; kappa-carrageenin producing species.

2. E. arnoldii — Thallus erect; “coral-like” in appearance, branching irregular; branches anaxiferous with compound whorls of simple and/or branched spines, or these may cover the entire distal portion of the branches to obscure the whorled arrangement of the determinate branchlets; kappa-carrageenin producing species.

3. E. cottonii — Thallus prostrate, attached by hapters at ventral part of branches; branches become fused with each other at certain portions to form crust-like mass; semi-erect branches may be formed in plants growing in habitats less exposed to strong wave action; dorsal portions of the branches generally “mottled” in appearance; anaxiferous, kappa-carrageenin producing species.

4. E. denticulatum — Thallus erect, branching from the main axes irregular; branches cylindrical characterized by the presence of regularly whorled determinate branchlets (spines); whorled arrangements of spines in the older portions of branches is obscured by the development of adventitious spines; axiferous, the core of axial hyphae persistent throughout the branches; iota-carrageenin producing species.

5. E. gelatinae — Thallus prostrate, attached to substrate by hapters from the ventral side of the thallus; branches segmented, flattened; with spines at the margins and the ventral surface of the branches; axiferous, with many flexuous medullary filaments extending throughout the segment; kappa-carrageenin producing species.

6. E. procrusteanum — Thallus erect, of a single flattened blade or may be segmented consisting of several flattened blades; anaxiferous.

7. E. striatum — Thallus erect, axes not percurrent roughened by presence of spinose determinate branchlets; branching close, branch axils angular; branches generally uniform in diameter and abruptly tapered to the apices; branches partly axiferous, medullary core of axial hyphae present in main branches not less than 5 mm in diameter.

2.2.2 The genus Hypnea

The genus Hypnea belongs to the Family Hypneacea, Order Gigartinales. Although many species are listed in Philippine literature, it is not generally well known. No monographic studies on the genus has been done for the Philippines and other tropical Asian countries. Many of the binomials cited in the literature for the Philippines appear to have been misapplied.

The thallus is generally fleshy and crispy. Like most species of Gracilaria the branches collapse when pressed between fingers. Branching is irregular, the branches are generally cylindrical or slightly compressed at certain portions; monoxial with apical cell very prominent at the tips of the branches/branchlets. Determinate branchlets spinose. Both the gametophyte and sporophytic generations are large and of the same form (isomorphic). Fertile female plants produce prominent cystocarps while the tetrasporophytes produce tetrasporangia in swollen stichidia on the determinate branchlets (spines); tetrasporangia are zonate.

Brief descriptions of the species

1. H. cervicornis — Plants forms loose clump; branching irregularly alternate; branches cylindrical; determinate branch-lets mainly simple abruptly pointed at the tip (spines). The presence of “cervicorn” branches/branchlets is a distinct feature stichidia pedicillate, swollen and borne mostly at the middle portions of the spinose branchlets.

2. H. cornuta — Plants forms loose clump; branching irregularly alternate; branches slightly compressed, determinate branchlets mainly simple sharp spines; the presence of stellate branchlets in addition to the simple forms is a distinct character of the species.

3. H. esperi — Plants small, forms loose clump; branching irregularly alternate; branches fine less than 0.5 mm in diameter; determinate branchlets gradually tapering to a sharp point. Tetrasporic stichidia are found at the tip or just below the tip of the branchlets (spines).

4. H. pannosa — Plants form dense thick mats; branching irregularly alternate to somewhat pinnate to irregularly divaricate; branches fused with each other at some parts, slightly compressed or subterate with many short, stout spinose ultimate branchlets; tetrasporangial stichidia saddle-shaped, formed on one side of the spinose branchlet.

5. H. valentiae — Plants erect, forming loose tuft; branching lax, irregularly alternate the percurrent main axis and cylindrical branches covered with relatively dense, long, slender, cylindrical determinate branchlets which are simple of branched. The tetrasporic stichidia form swollen bands around the determinate branchlets a short distance from or often very near the base, or occasionally forming swollen cap at the tip of very short branchlets.

2.2.3 The genus Acanthophora

This genus belongs to the Family Rhodomelaceae of the Order Ceramiales. Two species are known in the Philippines. A. spicifera and A. muscoides. Recent study showed that A. spicifera contains iota-carrageenin.

The thallus of A. spicifera is fleshy and like Hypnea the branches collapse when pressed between fingers. The thallus is erect and the main axis is percurrent. Determinate branches are spirally arranged/attached along the main axis at regular intervals The determinate laterals bear spirally arranged spines.

Both gametophyte and tetrasporic thalli are commonly collected. The female thallus bears distinct urn-shaped cystocarps while the male thallus on the other hand forms tetrahedral sporangia at the swollen tips of the spines.

2.3 The Philippine alginophytes

The alginophytes are alginate-bearing seaweeds. The known alginophytes belong mainly to the genera Sargassum, Turbinaria, Hormophysa, Cystoseira and Hydroclathratus. The genera Sargassum and Turbinaria are proven raw materials for the manufacture of alginates in some Asian countries. The last three genera and several others have been shown to contain alginates but the potentials of Hydroclathrus, Cystoseira and Hormophysa over the others are higher because of these are available in large quantities from natural stocks. These genera are also common components of seaweed communities in Asian countries and Western Pacific.

The genera Sargassum and Turbinaria belong to the Family Sargassaceae and Hormophysa to the Family Cystoseiraceae of the Order Fucales: Hydroclathrus on the other hand belongs to the Family Scytosiphonaceae of the Order Dictyosiphonales.

2.3.1 The genus Sargassum

The taxonomy of this genus is very difficult and may be considered a nightmare among the taxonomists. Very little is known about this large genus in the Philippines. It is, however, a very common component of seaweed communities and is distributed widely in the country. More than 30 binomials (names) for Sargassum have been listed in the literature (Velasquez, Trono and Doty, 1975) but the correctness of more than 80 percent of these names are suspect.

The difficulties in the taxonomy of this genus stem mainly from the fact that this is a very polymorphic genus. Sargassum is perennial and the primary growth and the succeeding growth (2nd year) phases are entirely different. In addition, the old binomials which have been applied to the different taxa were based only on portions of a thallus or of a growth stage of thallis of a taxon. As far as I am aware, the only authoritative work on Philippine Sargassum is that of Ang (1987) although the work was limited only to the Sargassums in Calatagan, Batangas and includes seven species.

Key to the species reported from Balibago, Calatagan, Batangas:

The binomials included in the above key are considered as correctly applied binomials to the Sargassum species. In addition, the following are also considered as good species: S. polycystum, S. cristaefolium, S. polycystum differs from S. siliquosum by its ramifying (branching) holdfast in contrast to the non-branching holdfast of the latter, other morphological characteristics as the size and shape of the leaves, the presence of numerous, small floats in mature plants and the rough or muricate nature of the primary branches are quite identical. They also differ in the type of habitat, i.e., S. polycystum grows in the inner protected portions of the reef where water movement is minimal while 5. siliquosum inhabits rocky habitats exposed to relatively strong waves/currents.

Sargassum cristaefolium ( = S. duplication) appears to be similar in appearance to that of S. crassifolium based on their morphology. The two species differs on the nature of the “duplicate leaves”. In S. cristaefolium, the large relatively thicker leaves are duplicated at their tip portions, i.e., the “double” apical portions involves the distal portion of the blade in contrast to 5. crassifolium where the “double” apical portions of the leaves only involves the edges of the apical margin of the leaves as indicated by the double rows of teeth.

Detailed descriptions of the different species are found in the paper of Ang and Trono (1987).

2.3.2 The genus Turbinaria

The genus Turbinaria (Family Sargassaceae, Order Fucales) is one of the brown seaweeds which is as common as the genus Sargassum. It is also one of the major components of seaweed communities although it is not as abundant (biomass) as the latter. This genus is quite well known in the Philippines. It is represented by the following species: T. ornata; T. decurrens; T. conoide and T. luzonensis. The first three species are well known and widely distributed in tropical Asia and Western Pacific Region.

The thallus of Turbinaria is fleshy and consists of rhizomatous or hapteroid hold-fasts from which a simple or branched erect axis arise. The leaves are of different forms depending on the species, i.e., may be triangularly obpyramidal, turbinate or peltrate in shape. The truncate top of the leaves is in most species, with thin expanded blade-like margin. In one species, T. luzonensis, the expanded margin is very much reduced or lacking. Except for few varieties, the leaves of Turbinaria possess air bladder or vesicle immersed in the swollen distal portion of the leaves.

Like in Sargassum the gametangia are produced in conceptacles embedded in the receptacle.

Brief description of the species:

1. T. ornata — Thallus coarse, dense and fleshy. Leaves large distinctly turbinate with terete stalk. Distal marginal blade moderately expanded and often reduced in one side; thick, rounded to triangular from top view; margin of the blade with coarse teeth; in the center of the blade is the vesicle, on top and around it is a crown of teeth. The teeth are absent in some varieties. Receptacles is branched, racemose and attached on the stalk of the leaves.

2. T. conoides — Thallus lax, to more than one meter long; stipe or axis branching; leaves numerous, stalked, the distal marginal blade thin and well-developed, generally triangular in top view, the margin sharply dentate; the body of the leaves abruptly inflated due to the presence of a prominent vesicle.

In most materials, the leaves are companulate in form with well-developed vesicles.

Receptacles : are attached near the base of the stalk of the leaves.

3.T. decurrens — Thalli mainly short; compact; erect stipe unbranched. Leaves distinctly triangular from the top view, the distal end abruptly cut, the distal blade very much reduced to a sharp, thick minutely dentate margin. The lateral faces of the leaves are separated by sharp dentate ridges extend to the distal end of the leaves. Vesicle small, deeply embedded in the leaf.

Receptacle racemose, dense and attached to the base of the leaves.

4. T. luzonensis — Thallus small to 10 cm tall. Erect axis simple or with few laterals. Leaves small, sharply inflated towards the distal end with well-developed vesicle. Distal marginal blades absent or very much reduced to a narrow ridge which may be sparingly toothed. Top view of vesicle is rounded to slightly triangular. Receptacle racemose and attached at the base of the stalk of the leaves.

2.3.3 The genus Hormophysa

This genus Hormophysa (Family Cystoseiraceae. Order Fucales) is also a common component of seaweed communities usually mixed with Sargassum and Turbinaria. It is represented by only one species, H. triquetra.

The thallus is large, bushy and fleshy and grows up to 40 cm tall. It is attached to the substrate by a discoid holdfast from which erect axes arise. The branches are foliaceous and segmented, the segment commonly with centrally disposed oblong vesicle embedded inside. The segments are more distinct in fertile materials and the narrow or reduced blade make the segments distinctly tri-ridged. The segments especially towards the distal portions of the fertile thallus are triangular in cross-section with the ridges extended into thin narrow blades. In sterile materials, segments especially at the basal portion, have broadened, well-developed blade. The margin is serrate to dentate.

2.4 Seaweeds utilized as food

Seaweeds have long been utilized as food by people living along the coastal areas in the country. These are prepared as fresh salad vegetable or blanched in boiling water and prepared into salad. Others are used as vegetables mixed with fish or meat. Some are also prepared into dessert gels.

A large number has been listed as food but the following species are commonly utilized:

REFERENCES

Abbott, LA. 1985 Gracilaria from the Philippines. List and distribution of the species In. LA. Abbot and J.N. Norris" (eds.), Taxonomy of Economic Seaweeds,pp. 89–90.

Ang, P.O., Jr. and G.C. Trono, Jr. 1986 The genus Sargassum (Phaeophyta, Sargassaceae) from Balibago, Calatagan, Philippines.Botanica Marina 30: 387–397.

Doty, M.S. and J.N. Norris. 1985 Eucheuma species (Solieriaceae, Rhodophyta) that are major source of carrageenan. In.I.A. Abbott and J.N. Norris (eds.),Taxonomy of Economic Seaweeds,pp. 47–62.

Saito Y. 1969 The algal genus Laurencia from the Hawaiian Islands, the Philippine Islands and adjacent areas. Pac. Sci. 23(2): 148–160.

Sullivan, J.J. 1985 Preface. In. I.A. Abbott and J.N. Norris (eds.), Taxonomy and economic seaweeds with reference to some Pacific and Carribean species. Report No. T-CSGCP-011: vii-viii Calif. Sea Grant Publication.

Trono, G.C, Jr. 1974 Eucheuma-farming in the Philippines. U.P. Natural Sciences Research Center Publication. Diliman, Quezon City. 13 pp.

Trono, G.C. Jr., R. Azanza-Corrales and D. Manuel. 1983 The genus Gracilaria (Gigartinales, Rhodophyta) in the Philippines. Kalikasan, Philipp. J. Biol. 12 (1–2): 15–41

Velasquez, G.T., G.C. Trono, Jr. and M.S. Doty. 1975 Algal species reported from the Philippines. Phil. J. Sci. 101 (3–4): 115–169.

Annex A
LIST OF COMMERCIALLY IMPORTANT SEAWEED SPECIES

¹ Professor, Marine Science Institute, College of Science, University of the Philippines, Diliman Quezon City, Philippines and Training Director, Seaweed Farming Training Course, 2–21 May 1988.

Lecture 8
PRODUCTION OF ECONOMICALLY IMPORTANT SEAWEEDS THROUGH CULTURE AND HARVESTING OF NATURAL STOCKS¹

by

Gavino C. Trono, Jr.²

1. PRODUCTION OF SEAWEEDS THROUGH CULTURE

1.1 Pond culture of Caulerpa

Several species and varieties of Caulerpa are presently utilized as food in the form of fresh vegetables in many areas of the Philippines. These are mainly produced through gathering of natural stocks. Only C. entillifera is commercially cultivated in ponds. The culture of this species started in the early 1950s on the island of Mactan, province of Cebu, Central Visayas. The accidental introduction of C. lentillifera with some other seaweed species to fishponds as fish food initiated its formal cultivation. The high demand for this alga on the local markets in metropolitan Cebu was a major factor contributing to the success of its commercial production. The species is preferred because of its delicate, light, taste, soft and succulent texture. It is also a fast growing species.

The pond culture of C. lentillifera was started by a fish farmer in 1952 utilizing his fishponds with milkfish and shrimp. At the beginning, Caulerpa was a secondary crop to fish and shrimp but later, because of the marginal production of fish and shrimp compared to the high production of Caulerpa, the farmer shifted to Caulerpa as his major crop and milkfish and shrimp became secondary crops. Interviews made among farmers revealed that some 80 to 100 hectares of ponds are presently used for the culture of Caulerpa. Although the commercial culture of Caulerpa in ponds started more than two decades ago, it has not been successfully transferred to other parts of the Philippines as yet, with the exception of a small production pond in Calatagan, Batangas so that the bulk of the fresh supply of Caulerpa in Metro Manila and some bigger towns in Central Luzon still comes from Mactan, Cebu. Although local consumption statistics are not available, it is probably safe to assume that several tons of Caulerpa are transported to Metro Manila from Mactan, Cebu every month. This seaweed is always available on the local markets any day of the week. The statistics of the Bureau of Fisheries and Aquatic Resources showed that in 1982 some 827 tons of Caulerpa was exported to Japan and Denmark in fresh, brine-cured or salted form.

The present cultivation utilizes the traditional fish and shrimp culture ponds. However, results of recent studies (Trono, 1986, in press) have shown that water management is a primary factor in the productivity of Caulerpa, the culture of which would require a flow-through system to facilitate water exchange. Thus, some modification of the traditional ponds such as the introduction of control gates has to be made. Unlike pond fish culture where water exchange is relatively infrequent, (e.g. once a week or a fort-night) pond culture of Caulerpa requires more frequent water exchange in order to maintain the necessary level of nutrients for growth and development. Some of the more progressive farmers in Mactan, had through experiences, learned the importance of proper water management and achieved higher production through the introduction of some form of a flow-through system by providing both entry and exit gates for each pond compartment.

The development of a new area into Caulerpa ponds consists of several stages, namely, site selection, pond construction, planting of the ponds, maintenance of the culture, harvest and post-harvest activities. Fishponds with marginal production are usually preferred because initial investment for their conversion to Caulerpa ponds is low and usually the location of these unproductive fishponds fits the ecological requirements of Caulerpa culture, that is they are far from sources of freshwater and pollution.

1.1.1 Site selection

The following factors have to be considered when selecting sites for pond culture of Caulerpa.

a) The area must be near to the source of unpolluted seawater supply. Caulerpa is consumed fresh thus, it must be grown in areas free from both communal and industrial pollution. Bacterial contamination of the crop should be avoided. Caulerpa may absorb pollutants such as heavy metals and toxic chemical which it can accumulate with deleterious effects to the consumers.

b) The site must be far from sources of freshwater such as rivers and streams. Caulerpa is a stenohaline marine alga and will die even in slightly brackish seawater when salinity drops below 30 ppt.

c) The elevation of the pond bottom must be at or just a little above the zero tidal level. This is necessary in order to enhance proper water management in the ponds.

d) The site must be protected from the destructive effects of wind and waves. A buffer zone of mangroves or coral reef is necessary.

e) The substrate must be loamy-muddy, however, very deep, soft mud must be avoided.

1.1.2 Pond construction

The maintenance of good water quality in the ponds through proper water management is dependent on the proper design of the ponds. The traditional layout of ponds for milkfish and shrimp production does not provide the necessary water exchange required in Caulerpa culture. Caulerpa ponds may be divided into compartments of 0.10 to 0.25 hectare and should have a flow-through design, that is each of the compartments should be provided with individual entrance and exit gates positioned in such a way that the water could easily be changed and circulated during the draining and flooding process. Peripheral or diversion dikes may also have to be provided to divert runoff water from the ponds during rains.

1.1.3 Planting of the ponds

The ponds are drained to a depth of 0.3 meters to facilitate planting. During the early development of the culture broadcasting was used to seed the ponds with Caulerpa cuttings. However, this technique was found to be inefficient because the “seeds” were not uniformly distributed on the pond bottom which resulted in uneven growth of the crop. An initial stocking rate of 1 000 kg per hectare under favourable weather conditions can produce a good crop in about two to three months.

The farmers have evolved some practical ways of seedling the ponds to ensure uniform distribution of the “seeds”. Planting is done by burying into the mud one end of a handful of Caulerpa cuttings at about one meter intervals. Uniform planting is facilitated with the use of guidelines or the planted areas are marked by pieces of bamboo. After planting, the ponds are flooded to a depth of about 0.5 to 0.8 meter. Flooding is done slowly to prevent the newly planted cuttings from being uprooted. The newly planted ponds are inspected a day or so after planting and the barren areas are replanted to ensure uniform growth. The pond water is changed only several days after planting to make sure that the cuttings have well rooted and could not be carried away by water currents.

1.1.4 Water management

Proper water management is a key factor in the successful pond culture of Caulerpa. Ideally, the pond water must be changed in only every three to four days at the start of the growing period in order to avoid strong water currents which may uproot the seedlings. The frequency of water exchange is increased to every other day at about the third week after planting especially when the plants start to form a thick growth on the pond bottom. Frequent water exchanges provide fresh supply of nutrients for the normal growth and development of Caulerpa thus, it will eliminate the need for fertilizer application.

In general, the water in the ponds is maintained at a depth where the Caulerpa is visible from the surface of the water. Thus, the depth would vary depending on the transparency of the pond water to provide enough light for the plants. However, adjustments in water depth should be made to avoid perimeter dikes from collapsing during spring tides when the tidal amplitudes are extreme. During rainy days, the pond water should be maintained at a slightly greater depth to reduce the possibility of a dilution below 30 ppt. Caulerpa will die when the salinity goes below this level thus, the entire crop might be lost. After heavy rains, the pond water should be immediately drained and replaced by fresh seawater to ensure that the salinity is maintained at or above 30 ppt.

Fertilization may not be necessary as long as frequent water exchange can be granted. However, fertilizer has to be applied especially one or two weeks before the harvest, when a large biomass has already been produced and the plants appear to be pale in color (that is light green or yellowish). The sufficient rate of fertilization is about 16 kg per hectare. Nitrogen fertilizers have produced very good results. The plants regain their healthy color a few days after application. The fertilizer may be broadcasted but past experience has shown that wrapping the fertilizer in many layers of gunny or plastic bags and suspending these in strategic places in the pond at a level where the bags are just about half submerged in water, produces very good results. The fertilizer is applied right after water exchanges. The pond water should not be exchanged for several days after fertilizer application.

Weeding is an important activity which is done regularly to remove other seaweed species and associated organisms growing in the pond. Weeds compete with Caulerpa for space, light and nutrients. The weeds and the associated organisms should be removed before they take over as dominants. The presence of the weeds results in decreased production and low quality of the product and adds extra labor cost to sort them out before the product is sold in the market.

The dikes and gates of the ponds must be continuously maintained to grant efficient water management. This is especially critical during the monsoon season when strict and efficient water management is required to avoid extreme dilutions due to heavy rains.

1.1.5 Harvesting and post-harvest activities

Depending on the growth rate of the plants the crop may be harvested two months after the initial planting, when the plants form a relatively uniform carpet on the pond bottom. The plants at this stage are of high market quality, light grassgreen in color, soft and succulent in texture. Older plants though high in biomass are of lower quality because they are tougher in texture and their lower portions near the bottom are pale or colorless. The paling of the basal portions of the fronds is caused by self-shading when the plants become older and form a very thick carpet.

During the early stages of farming, the crop was completely harvested and the ponds were replanted afterwards. Harvesting was done by uprooting the plants from the pond bottom. The farmers, however, discovered that more crops could be produced during a growing season if partial harvesting is done, that is a sizeable amount (20–25 percent) of the crop is left in the pond to serve as seedstock for the next crop. Harvesting in this case is made in such a way that the leftover of the crop is more or less uniformly distributed in the pond. Barren areas are then replanted to ensure uniform stand. This practice has drastically reduced production costs by savings made in labor costs for replanting. The sizeable amount of seedstock left in the pond also results in a much shorter growing period and farmers claim they can harvest every two weeks after the first harvest during the optimal growing season (dry season).

Harvested seaweeds are thoroughly washed in seawater to remove the mud and other uncleanlinesses. They are then sorted, unsuitable thalli and other seaweed species are removed. The clean seaweed is placed in bamboo baskets. The side and the bottom of the baskets are lined with banana leaves or other seaweeds such as Sargassum which are also placed on the top of the filled baskets. The baskets are placed under the shade where they are allowed to drip before transportation to the market. The product can stay fresh for four or five days.

Caulerpa destined for export to other countries (such as Japan) is exported as a fresh product or in brine-cured or salted form. The seaweed is first thoroughly washed several times in seawater. Then thalli of good quality are selected. The clean seaweed is first completely drained of water, packed in styrofoam boxes provided with aeration holes on the upper side or cover of the box, taped and sent to its destination by air cargo. A large portion of Caulerpa exported to other countries is either brine-cured or salted. The latter two forms can be kept for longer periods and may be transported by surface cargo.

1.1.6 Progress and problems

While Caulerpa farming has been proven to be a profitable venture, it has not developed to a large-scale industry as yet. Important factors which have hindered the development of Caulerpa farming are the low local demand for Caulerpa, the use of traditional (extensive) fishponds for its culture, lack of technology transfer to other areas and untapped local potential demands. At present, the distribution of Caulerpa produced in Mactan is limited to Cebu City, Metro Manila and probably some cities in the southern Philippines. Only a small fraction of the population in these cities consumes Caulerpa. In general, people who buy Caulerpa are those who have been used to eat this seaweed long before they migrated to the cities. Majority of city residents do not eat seaweed of any kind. The sharp rise in the price (up to P22 per kg retail price in Metro Manila) may have also contributed to the decrease in demand for this seaweed.

Many of the farmers in Mactan still use the traditional fishponds for the production of Caulerpa. This is the reason why their production per unit area is quite low. In contrast, experimental ponds of the University of the Philippines using a flow-through system (Trono and Denila, 1986, in press) produced between 12 to 15 tons per hectare per year despite the very low production during the rainy months of July to October. As it was pointed out earlier, the layout of the traditional fishponds does not grant the necessary water exchange for a productive Caulerpa pond. This is the main reason why farmers using the traditional fishponds achieve very low yields compared to some of the more progressive ones.

The distance of the growing areas from market outlets is a factor limiting supply in areas far from Mactan, for instance in Metro Manila, contributing to high retail prices of this seaweed. The problem is due to the fact that culture techniques of this seaweed has not been transferred to other areas as adequate information on the technology and feasibility of Caulerpa production is still missing. The construction of new farms in areas with high potential demand for Caulerpa will be critical in the development of this industry. Recent studies (Trono, 1984, unpublished) have shown that the population in northwestern Luzon province consumes a sizeable amount of local seaweed species which include Caulerpa as a top favorite. The natural beds of Caulerpa in Bolinao, Pangasinan which serve as the main source of this seaweed for the population centers in the area are now depleted. A part of the imported Caulerpa from Mactan, Cebu finds its way to these big population centers in Pangasinan and La Union but transport is expensive. The population of the two Ilocos provinces in the north are also known to utilize local seaweeds for food. The development of Caulerpa culture in Pangasinan or La Union would, therefore, be very feasible because the local demand for the product is high and the area, also well known for its fish and shrimp aquaculture have ample pond facilities for seaweed culture.

1.2 The culture of Eucheuma

During the early 1960s, the Indonesian archipelago was the main source of dried Eucheuma for the American carrageenan industry. The supply of dried seaweed came from harvesting natural stocks. The advent of political problems in the mid-sixties had drastically affected the supply and the American company was forced to locate new resources. The Philippines was a natural choice because Eucheuma also abound on the shallow reef areas of the country. Thus, gathering of wild stocks started and after three to four years of intensive harvesting the easily accessible reefs supporting natural stocks of Eucheuma became depleted. Measures to control overexploitation of stocks did not succeed because of the tendency of the seaweed collectors to remove everything they found. In the late sixties, the annual production of a few hundred tons of dried seaweed was maintained by locating new stocks in far-flung areas but this resulted in high production costs. By now it became apparent that the harvest from natural stocks cannot satisfy the increasing demand of the industry and efforts to develop the culture of this seaweed were initiated. The initial activities and problems encountered in the development of Eucheuma culture have been described by Doty (1973), Doty and Alvarez (1973), Parker (1974) and Trono (1974). By now Eucheuma culture has grown to a medium size industry producing some 20 000 to 25 000 tons of dried Eucheuma during the past five years from about 6 000 to 7 000 hectares of family farms in the southern Philippines and Central Visayas where not less than 20 000 people are directly involved in farming. The industry was estimated to be producing some 300 million pesos in 1983.

1.2.1 Species under cultivation

A recent report on a new species has resulted in a total of seven species now reported from the Philippines. These are Eucheuma cottonii, E. arnoldii, E. procrusteanum, E. gelatinae (= E. serra), E. striatum, E. denticulatum (= E. spinosum) and the newly described E. alvarezii (Doty, 1985). The taxonomy of these Philippine Eucheumas and of those reported from other parts of the world has been reviewed by Doty and Norris (1985). At present two species, namely, E. denticulatum and E. alvarezii are the main species under cultivation, although a third species, E. striatum, may be occasionally found mixed with these two in some farms. E. denticulatum earlier referred to in the literature on seaweed farming as E. spinosum is an iota-carrageenan producing species and is known as the “spinosum type” of commodity. E. alvarezii referred to earlier as E. striatum is a kappa-carrageenan producing species and is called the “cottonii type” of commodity.

1.2.2 Methods of cultivation

The farming of Eucheuma had undergone through some changes in two major areas, that is in culture techniques and in its organization and management. Different methods of cultivation were tried in the past from the very simple bottom culture to the more sophisticated types using some form of' a support system such as the raft method, the fixed off-bottom method, the tubular net method and the monoline method. The change in the organization and management was a shift from the highly organized “hacienda-type” or company farms to individual family farms.

In the bottom culture cuttings of Eucheuma are attached to pieces of corals and arranged on the bottom into plots of uniform sizes. While this method is easy to practice, it is not very productive. The plants are easily attacked by benthic grazers or are easily displaced when the area is affected by even a moderate water movement.

In the raft method, a pair of 2.5 to 5 meters monofilament nets with mesh size of approximately 30 cm are attached and stretched to a 6 × 6 meters bamboo raft. Cuttings of 50 to 100 grams are tied to the intersections of the nets. The rafts are anchored to the bottom. Approximately 225 to 300 plants can be planted on such a raft. The raft method is not used at present for commercial purposes as the costs of materials, labour and maintenance are quite high.

In the tubular net method, the planting material is placed on a strip of monofilament netting (2 cm mesh, 12–15 cm wide and one to two meters long) mounted on a seeding board. The edges of the netting are laced with a nylon braided string to form a tube with the cuttings inside and the ends of the tube are closed by tying these with the nylon string which also serve as a support. The seeded tubes are then attached either to a raft or to wooden stakes. Harvesting is done by pruning the branches of the plants outside the tubing. This method has also, high material and maintenance costs and is not very productive. It was not adopted in the commercial production.

In the fixed off-bottom culture method, the monofilament nets (as described above) are stretched horizontally above the bottom and their corners are tied to wooden bipods or tripods which serve as supports. Four modules consisting of two hundred nets each form a hectare where approximately 102 000 cuttings can be planted. This method grants an intensive type of farming but was later replaced by the monoline method presently used in both small family farms and large company farms. Although productivity of the fixed monofilament nets vs relatively high costs of materials and maintenance and the difficulty in planting and harvesting were the factors which caused the farmers to shift to the simpler, cheaper and easy to maintain monoline method. This latter method is an extensive type of farming where only 34 000 to 35 000 cuttings are planted on a hectare.

1.2.3 Site selection

Unless it is in an area already having Eucheuma culture, any attempt to open new areas for farming should be preceded by careful site selection. Reconnaissance survey of reef areas should be made and potentially good portions of the reef should be identified and subjected to intensive in situ growth rate studies. The following general guidelines could be used in the preliminary evaluation of sites. Reefs far from freshwater sources are preferred because Eucheuma is a stenohaline marine alga and salinities below 30 ppt may have adverse effects on it. The area should be protected from the destructive effects of wave action thus, the presence of buffer zones is necessary to minimize these effects.

Areas which are about two to three feet deep with coarse sand to coralline substrate and subject to a moderate water current have been found to support good Eucheuma farms. Water movement in general favors the growth of Eucheuma by facilitating rapid nutrient absorption. It also prevents extreme fluctuations in other ecological factors (temperature, salinity, pH, dissolved gases, etc.), which can adversely affect the growth of plants. The firm substrate is essential for the support system and also reflects the existence of water movement in the area. Portions of the reef characterized by soft substrates such as fine sand or silt are generally not good for Eucheuma farming. Water depth at low tides is also an important factor because it affects the cost of farming. Areas with a depth of two to three feet at low tide are ideal. Deeper areas are hard to cultivate as the construction of the support system, the planting and harvesting in deeper water will entail higher costs in labor and materials. Reef areas supporting natural stocks of Eucheuma are good potential sites.

After a site have been identified, test planting of the desired species is recommended. Test plots consisting of a few monolines planted with 50 to 100 test plants each are constructed at different strategic locations of the area. The size of the seedlings and the culture method of the test plots follows the farming practices except for the small size of the plots which is about two by five meters. The growth of the test plants is monitored at weekly intervals and their daily growth rates determined. Areas supporting daily growth rates of two to five percent are potentially good sites. Although two to three months long monitoring of the growth rate may be enough to start a small family farm, it is advisable that the development of a commercial size farm should be based on a whole year-round monitoring, considering the possibility of problems associated with the seasonality in the growth of Eucheuma. This precautionary step should be strictly observed if the site is in a newly opened area. However, if adjacent areas are already being farmed, short-term growth monitoring will suffice. In general, areas in which the test plants double their size within 30 days or less are productive areas.

1.2.4 Construction of the support system (the monitoring method)

The development of the farm starts with the clearing of the site of seagrasses, seaweeds, large rocks and corals. The area is then divided to smaller sections of 1/4 of a hectare or smaller. The following is a brief description of the monoline method presently used by farmers.

Construction of the support system starts with drilling holes in the bottom with the use of a pointed iron bar (two inches in diameter) and a heavy sledgehammer. Then pointed mangrove stakes about two inches in diameter and 60 to 80 cm long are firmly driven into the holes using the sledgehammer. The wooden stakes are arranged in rows at one meter intervals and the distance between the rows is 10 meters. A loop is made at one end of the monofilament line (180–200 lbs test nylon) and it is attached to a stake. The line is then strongly stretched and its other end is firmly attached to the opposite stake in the next row. The distance of the monofilament line from the ground is approximately 0.3 to 0.5 meter depending on the depth of the water during low tides. The monolines may be positioned parallel with or crosswise to the direction of the current depending on the strength of the current. In areas where the current is relatively strong, the monolines are arranged parallel to the current and an extra stake is placed midway between the original rows of stakes to provide extra support for the monoline. The shorter the distance between the rows of stakes, the stronger the support system, but a reduced distance will result in additional costs. Adjustments in the construction of the support system may be made to adapt to the needs of a specific area. One thousand pieces of 10 meters long monolines will make a hectare of farm.

1.2.5 Preparation of seedlings

Seedlings of the selected species or variety are acquired from the nearest source. These are transported to the farm site in the shortest possible time and protected from exposure to sun, rain and wind. If the seedlings are in transit for longer periods, they should be occasionally soaked with clean seawater. Experiences have shown that for long distance transport of seedlings the use of styroform boxes with quarter-size holes at their upper sides to facilitate aeration is the most efficient method. The seedlings should be drained of excess seawater before being placed in the box and covered. They must immediately be placed in seawater upon arrival to the farm site.

“Seeds” for planting are prepared by tying SO to 100 grams bunches of cuttings with soft plastic tying materials commonly called as “tie-tie”. The bunches are then tied at 20 to 25 cm intervals to the monolines already stretched in the sea. Maintenance and management of the farm are facilitated by planting on a unit area basis that is a farm unit should be fully planted before proceeding to the next one. The plants are ready to be harvested when they are about one kilogram in size or bigger. The time required to grow Eucheuma to harvestable size vary depending on the ecological conditions. Seasonality in growth is a common phenomenon in some areas of the Philippines.

1.2.6 Maintenance of the farm

The maintenance of the farm consists of weeding, repairing the support system, replacing lost plants and removal of benthic grazers. Other species of seaweeds grow in close association with Eucheuma as epiphytes or on the monofilament lines and stakes. These compete with Eucheuma for nutrients, light and space. They also add to the “drag” on the line in areas with a strong current which result in breakages and losses of plants. Grazers such as sea urchins and starfishes have been demonstrated to consume significant amounts of seaweed resulting in severe losses of biomass. Maintenance is a necessary component of farming which significantly influences production. In areas characterized by strong currents, a retaining fence made of nylon nets with approximately 10 cm mesh size should be constructed at the leeward side of the farm to catch thalli washed out by the current. In northern Bohol, about a fourth or a third of the daily harvest consists of these washed-out materials.

1.2.7 Harvesting

The present practice of farmers is to harvest the whole plants and to replant the farm with new cuttings. The best plants from the harvest are used as seeding material for the next crop. This practice has replaced the pruning method formerly used by farmers in which the plants at harvest were pruned down to a 100 grams bunch or so to serve as the “seed” for the next crop. The objective ' was to save on planting cost as well as on tying material. This old practice, however, was found to be inefficient because the bunches left behind were old portions of the thalli which grew slowly thus, it took a longer period to produce the same amount of biomass after the first harvest. In addition, the “tie-ties” lasted only for one growing season anyway. But most importantly, the built-in mechanism of “seed improvement” by selection which is a big advantage of the present practice was not possible with the former method of harvesting.

1.2.8 Drying of the product

Drying is an important post-harvest activity which affects the quality of the product. The harvested crop is spread on drying platforms usually made of bamboo slots, cleaned of foreign materials such as old tie-ties, weeds, marine animals, nylon lines, etc., and spread uniformly under the sun to dry. This drying method has been slightly modified recently to minimize the loss of material and facilitate drying. The platform is now first lined with fine mesh braided nylon net and the crop is spread on top of it. The plants are regularly turned over to facilitate complete sun-drying. The drying crop should be protected from rains. Before the onset of a rain the crop is first piled up into a heap by just pulling the lining net to one part of the platform and then covered by a water-proof sheet. The product is dried in two to three days during a hot, sunny weather. The dried product should not contain more than 30 percent moisture. The dried material is tightly packed in nylon bags and stored in dry areas before shipment to buying centers.

At present Eucheuma is exported in three forms as dried, raw seaweed, as alkali-treated chips or as a semi-processed powder. Export of the last two forms appears to be the trend among the big exporters. This reflects the preference of these semi-processed products by big processors of pure carrageenan and by the pet food and canning industry. By importing semi-processed products such as alkali-treated chips, the processors of carrageenan are receiving good quality raw materials and they can avoid pollution problems associated with the disposal of wastes. The semi-processed powder form is directly utilized in pet foods and by some canning industries, a cheap substitute to the pure carrageenan.

1.3 The culture of Gracilaria

Although several species of agarophytes belonging to the genera Gelidium, Pterocladia and Gracilaria have been reported to be commercially produced through some form of farming in several countries such as Japan, China, Republic of Korea, Vietnam, India and the Philippines, it is in Taiwan where the production of Gracilaria through pond culture has achieved a high degree of success. Here, an average of 12 000 tons of dried Gracilaria was produced during the past few years (Chiang, 1981).

The genus Gracilaria is characterized by the alternation of three somatic generations, the sporophyte, the gametophyte and the carposporophyte stages. The last one is microscopic and it is parasitic on the female gametophytes thus, the gametophytic and sporophytic stages are the macroscopic forms used as planting materials in the pond culture. Although the reproductive potential of Gracilaria through spores is high, vegetative propagation by cuttings is presently used in the pond culture because of the very high regenerative capacity of the plant and the simplicity of the method. However, "hatchery produced" seedlings from spores have been demonstrated to be superior in the open field culture of Gracilaria (Doty, 1986).

Out of the several species of the genus presently used (e.g., Gracilaria chorda, G. edulis, G. verrucosa, G. lichenoides, G. compressa and G. gigas) G. verrucosa is the most popular due to its ability to adapt to a wide range of ecological conditions, its higher production rates and better gel quality. The culture of Gracilaria started in 1962 in southwestern Taiwan. Production in ponds is primarily influenced by three ecological factors, namely; salinity, light and temperature. High production is recorded during the months characterized by . higher temperatures and growth is slow during winter. High light intensity exerts adverse effects on the growth, therefore, control of light conditions is practiced by adjusting the water depth in the ponds. Salinity of 15 to 24 ppt appears to be optimal for growth. The increase in salinity during the summer months is controlled by the addition of freshwater thus, farms need to be located near freshwater resources.

1.3.1 Site selection

The success in pond culture of Gracilaria is highly dependent on the selection of appropriate sites. The following criteria are recommended in the selection of sites for pond culture.

• the site should be located near seawater and freshwater resources;

• the area should be protected from strong winds;

• the pond bottom should be at or near the zero tide level; and

• the pH of the water should be slightly alkaline, e.g., 8.2 to 8.7.

Gracilaria is a eurythaline species and can grow in brackish water under a wide range of salinity. A salinity range of 15 to 24 ppt have been found to be optimal. Salinity rises during the sunny months due to evaporation losses reaching values as high as 35 ppt or drops to as low as 8 ppt during the rainy season were shown to be detrimental to the crop. The maintenance of optimal salinity in the ponds requires readily available freshwater and seawater supply. The ponds should be located in areas protected from strong winds because there is a tendency for Gracilaria to accumulate the leeward side of the pond. The formation of thick heaps of Gracilaria in one side of the pond has adverse effects on the growth due to shading.

Water management is greatly influenced by the tidal changes in relation to the elevation of the pond bottom. Ponds located in areas where the bottom is at or a little above the zero tide level can easily be managed as water exchange is easy.

1.3.2 Culture ponds

The average size of ponds for the culture of Gracilaria is about one hectare or smaller. Smaller ponds are easier to manage than larger ones because in large ponds Gracilaria tend to accumulate at one side due to the influence of winds. Pond management is also easier when Gracilaria is polycultured with shrimp and/or crab. Provision of entrance and exit gates also facilitate proper water management.

The depth of the ponds vary from 50 to 80 cm clayish loam, silty loam or sandy loam. It was observed that Gracilaria easily gets buried in ponds with sandy bottom due to the effect of wind. This problem, however, could be resolved by increasing the depth of the water during windy periods. In larger ponds wind breaks consisting of bamboo slots are installed perpendicular to the direction of the wind to prevent the seaweed being transported to one side of the pond.

1.3.3 Culture method

The following method is generally followed in the pond culture of Gracilaria. The ponds are dried for several days, water is then introduced. Healthy stocks are selected as planting materials. These are generally characterized by their elastic feel to touch, reddish brown color, brittle texture, they must have stout and well-branched thalli and must be free of dirt and extraneous materials. The planting material is transported from its source to the pond site early in the morning to prevent its exposure to the sun. During long distance transport, it is frequently sprinkled with seawater and perforated bamboo or plastic pipes are inserted into the bottom of the heap to provide aeration. The plants must immediately be placed in the water of the pond upon arrival. The planting material is then cut into pieces and is broadcasted uniformly on the bottom of the pond. Stocking is usually made with 5 000 to 6 000 kg stocking material per hectare in April.

1.3.4 Pond management

The water is maintained at a depth when the surface is approximately 30 to 40 cm above the heap of the algae. However, the depth is increased to cover the algae by 60 to 80 cm during the warm summer months to prevent a significant rise in the water temperature. Water depth is also increased during the cold winter months to avoid temperature drops below 8°C which is lethal to Gracilaria.

Frequent exchange of water is necessary to maintain the optimum temperature of water in the ponds. The water is changed every two to three days. About 50 to 75 percent of the pond water is used to be drained and replaced with fresh seawater.

Fertilization with either organic or inorganic fertilizers is used to enhance the growth of Gracilaria. Weekly application of three kilograms of urea per hectare is sufficient. Fermented pig manure may be applied at a 160 to 180 kg per hectare dosage two to three days after the exchange of the water.

1.3.5 Harvest and post-harvest activities

The harvesting season starts in June and extends to November. The crop may be harvested every 10 to 40 days manually or by using scoop nets. The frequency of harvests is primarily dictated by the market price and the season. The crop is thoroughly washed in pond water to remove the silt, sand, pieces of shells and other extraneous materials such as snails and other algae. The clean Gracilaria is spread uniformly on bamboo screens or plastic sheets for drying. An average wet to dry ratio of 7:1 is generally attained.

Standards set by the Bureau of Standards in Taiwan for the export of dried Gracilaria require that the product should not contain more than 1 percent of mud and sand, not more than 1 percent shells and not more than 18 percent other seaweed species. Moisture contents should not exceed 20 percent. Dried Gracilaria is then packed into sacks of 100 kg weight for export or sold to local processing plants. Ten to twelve metric tons of dried Gracilaria are produced in a hectare of pond.

1.3.6 Polyculture with shrimp and/or crab

Polyculture with shrimp (Penaeus monodon) and/or crab (Scylla serrata) is mainly done in Ping-tung Prefecture in southwestern Taiwan. Stocking material for a hectare of farm consists of 4 000 to 5 000 kg of Gracilaria, 5 000 to 10 000 crab and 10 000 to 20 000 shrimp. Crushed trash fish and snails are generally used as feed for the crab. Crabs are harvested after three months, the shrimp often after four to seven months. Survival rates as high as 80 percent for crabs and 80 to 90 percent for shrimp has been documented making this polyculture one of the most profitable methods in Taiwan. The net income from polyculture has been proven to be three times as much as from monoculture.

2. NATURAL PRODUCTION OF COMMERCIALLY IMPORTANT SEAWEEDS

The “non-farmable” species as used in the present context are those which by the very nature of their small size, slow growth and regenerative capacities and/or determinate growth cycles do not easily lend themselves to the conventional way of farming through mass production through the use of cuttings or spores, e.g., Gelidiella acerosa, Gelidium spp., Sargassum sp., and Acanthophora. Their production depends primarily on the availability of naturally produced stocks as influenced by harvest pressures during the preceding season. Production of some of the species is highly seasonal depending on their growth cycles as influenced by environmental conditions. Their harvestable stocks are also significantly controlled by monsoons.

Because their growth cycles are highly dependent on the environmental conditions in their habitat and to a large extent to the degree by which these are influenced by man's exploitive activities, their production, therefore, is highly unreliable. The need to manage and conserve their natural stocks is of prime importance in order to assure to a certain extent their continuous production as well as to prevent overexploitation.

The design of a sound management and conservation scheme for non-farmable species depends primarily on the availability of information on the various aspects of their biology, e.g., reproduction and growth cycles, growth rates, their regeneration and recruitment capacities and their production potentials; The above information are necessary in the formulation of guidelines for the management of the natural stock of the target species. These information can provide answers to questions such as where the species is abundant, how much to harvest per unit area, when to harvest, how many times can the stocks be harvested in one season, what kind of harvest method is best for the species. Furthermore, production can be safely forecasted. These available information is most important in quoted contracts which may be entered into by the farmer, fishermen, or exporter. The gathering of these basic information on the species to be managed requires basic skills in methodologies for field sampling and data gathering.

Thus, it is of prime importance that any plan to exploit natural stocks of seaweeds must be preceded by intensive biological studies to determine seasonality in biomass production, reproduction, regeneration and recruitment. These information are necessary in determining the best possible time of harvesting and amount of harvestable stocks.

Production of non-farmable species can be enhanced by the application of some agronomic techniques with the primary aim of protecting the natural stocks from over-exploitation. The application of harvest techniques which are the least destructive is one way of assuring the fast recovery of stocks. For instance, harvest by hand picking (pulling) is more destructive than pruning. The removal of the whole plant from the substratum by hand picking reduces the capacity of the stocks to regenerate. Renewal of stocks through regrowth from basal portions left after pruning is very much faster than recruitment of new thalli from spores.

The removal of unwanted species (weeding) may enhance the growth and development of target species through eradication of competitors for space, light and nutrients. The clearing of the substrate also enhances the opportunity for recruitment by spores. Studies have shown that recolonization of bare substrates results to the increase in population density of the target species.

The eradication of grazers in reef areas being managed for wild crops contributes to the enhancement of production in reef areas. Sea urchins, starfishes and fishes like siganids are well-known seaweed grazers whose destructive effects on seaweed crops can be minimized.

The harvesting of seaweed crops from natural stocks is labour-intensive. Seaweed gathering for cash crops, therefore, offers an opportunity to optimize the utilization of the minimally used labour force in coastal areas. Methods being employed in the harvesting of natural stocks vary depending on the species, its size, abundance and the habitat where these are found. In tropical areas, most of the wild crops are found in shallow rocky portions of the reef or in shallow bays. In reef areas where harvestable crops are closely associated with other species, selective harvesting through hand picking and/or pruning are the most common methods of cropping. In shallow bays, the gathering of Gracilaria is done by hand, or with the use of rakes. In some instances semi-mechanized method is employed utilizing trawl-like equipment attached to a slow-moving motorized bancas. In deeper areas, diving and hand picking or the use of pruning tools are employed. Scuba is a convenient equipment now used in some countries for gathering wild stocks in deeper areas.

In wave-exposed areas where hand picking is hazardous, the gathering of seaweed crops is mostly dependent on drift materials which accumulate on the shore especially after some heavy surfs.

¹ Reproduced as hand-outs for this training from the paper entitled “Seaweed Culture in the Asia-Pacific Region”. RAPA Publication 1987/8, pp. 15–25 and from Report on the Training Course on Gracilaria Algae, SCS/GEN/81/29, pp. 45–46.

² Professor, Marine Science Institute, College of Science, University of the Philippines, Diliman Quezon City, Philippines and Training Director, Seaweed Fanning Training Course, 2–21 May 1988.

Lectures 9 and 12
SEAWEED INDUSTRY IN THE PHILIPPINES

by

Maximo A. Ricohermoso¹

ABSTRACT

The Philippines is one of the few countries in the world that has successfully grown marine algae (seaweeds) in substantial commercial quantities. Among marine and fisheries product exports, seaweeds and seaweed products now ranks third after shrimps and tuna. Compared to shrimps and tuna, however, seaweeds provide greater direct economic benefits to a greater number of our people.

Eucheuma seaweed species dominate the Philippine seaweed industry. Sargassum, Gracilaria, Gelidium and a few other species are commercially important, limited information is available thus, this paper will deal more on Eucheuma.

¹ President, Seaweed Industry Association of the Philippines, Mandaue City, Cebu.

1. EXISTING RESOURCES

1.1 Eucheuma cottonii and Eucheuma spinosum

Eucheuma cottonii and Eucheuma spinosum are the main commercially cultivated seaweeds in the country. Estimated harvest in 1986 was about 45 000 metric tons for both species with an estimated export value of about P500 000 000 ($25 000 000). The country's export of Eucheuma materials has been growing at an average rate of 30 percent per year during the last five years (Table 1).

Eucheuma is now cultivated and the main source of livelihood of about fifty thousand coastal-dwelling ocean farmers and fishing families in Tawi-Tawi, Sulu, Zamboanga de Sur, Sacol Islands, Palawan and Cuyo, Danajon reef of Central Visayas, Southern Leyte and other reef areas in the country. Eucheuma, of the red algae category is one of the most important raw material for carrageenan, a colloidal substance used as an essential. gelling agent, stabilizer or emulsifier in various food, personal care, Pharmaceuticals and industrial products worldwide.

Gracilaria and Gelidium are the raw mate-rials for agar which has major applications in food, pharmaceuticals and culture media for clinical and research laboratories.

Sargassum, however, finds major application only in animal feeds in Japan due to its lower alginate extract.

Caulerpa, known as “lato” is a green algae finding its place among sea food delicacies for local and foreign consumers.

Using present cultivation technology, the country could easily produce seventy to eighty thousand metric tons of Eucheuma annually.

1.2 Gracilaria, Gelidium, Sargassum and other species

Although known to be growing abundantly all over the coastal and reef areas of the country, there is no adequate inventory data on Gracilaria, Gelidium, Sargassum, Porphyra and other commercially important seaweeds. As late as the 1960's, Gracilaria and Caulerpa were harvested in Manila Bay and were important livelihood sources of coastal dwellers along the bay from Bataan to Cavite. Pollution, unfortunately, had already wiped out these important marine resources in the area.

2. EXISTING TECHNOLOGY

2.1 Cultivation and post-harvest processing

Cultivation technology of Eucheuma is adequate for the current needs of the industry. The present Eucheuma farming utilizes the monoline system which is easily adaptable to either bottom or floating methods, depending upon suitability of farming site. Eucheuma through this method is harvestable in 45 or 60 days.

Drying and storage are very important aspects of Eucheuma post-harvest handling. Poorly dried harvests and improper storage results to highly degraded produce.

Eucheuma harvests are simply dried under the sun, commonly in an extended platform beside the farmer's house. More often, however, the seaweed is left to dry over the sand in a make-shift mat of coconut leaves or nylon nets. This drying method yields low quality materials due to excessive sand and other foreign matter contamination.

3. PROCESSING AND END-PRODUCTS EXTRACTION

Raw material exports is now less than 50 percent of the total Eucheuma harvest, accounting for 38 percent of the export earnings of the seaweed industry in 1986. Local seaweed processors utilize more than 50 percent of Philippine Eucheuma harvests in the manufacture of carrageenan products, generating about 62 percent of the foreign exchange earnings last year.

Raw materials for export are sorted, foreign matters removed, redried and baled. Standard moisture content for raw Eucheuma export is 38 percent. Farmers deliveries range from 40 to 50 percent moisture.

Eucheuma processed product exports from the Philippines are either kappa or iota-carrageenan blended materials ready for use in their respective applications. These are manufactured either for use in their respective applications. These are manufactured either through extractive or non-extractive method. The dried seaweed material is cooked in an alkali solution to a desired modification level, washed, dried (either solar or mechanical) ground and blended to customers specifications. Rigid quality control is observed starting from the raw material to the finished product phases of the process. This Eucheuma processing technique, although well known and used in the U.S. and Europe in the earlier stage of carrageenan technology was initiated in the Philippines by Japanese chemists sometime in 1977 in a joint venture with a Cebu based Filipino company. The method since then has undergone several revisions. The Philippines is now the leading world supplier of carrageenan manufactured through the non-extractive method.

The extractive (refined) carrageenan processing method also involves alkaline cook of seaweed raw materials plus the more highly sophisticated and technically advanced KCL (potassium chloride) or alcohol extraction system. A newly built extraction, plant initially relying on Japanese technology is now operating in Cebu at 500-metric tons annual rated capacity.

Agar processing system has been an established technology in the country as evidence by the existence of agar manufacturing plants. The method simply involves pasting the raw materials, washing and drying either solar or mechanical. Agar locally known as “gulaman” is usually marketed in agar bar or strip form.

Sargassum processing involves sorting, cleaning, drying and grinding. Fishermen deliver Sargassum material at a 30 to 40 percent moisture content. The local processor-exporter redries the materials at 14 to 18 percent and milled to about 10 mesh.

4. MARKETING

Except for a minor local usage, Eucheuma harvests of the country is totally destined to the export market either in raw or carrageenan form. Raw Eucheuma cottonii material exports in 1986 was about 19 300 metric tons (Table 1) with an estimated value of US$7 720 000 (154 400 000).

Eucheuma spinosum was about 1 886 metric tons (Table 1), value estimated of US$1 037 000 (20 740 000).

The major use of Philippine Eucheuma harvests are the processing plants in Denmark, France, Spain, U.S.A., Korea, Japan, Argentina, Taiwan (Table 1), China (PROC) used to buy and remain potential big users of Eucheuma materials.

Table I. Philippine seaweed (Eucheuma sp.) industry profile December 31. 1987

Farm harvests

	Percent share	Metric tons	Seaweed farmers Direct economic benefit
Tawi-Tawi1	60	22 800	114 000 000
Sulu	12	4 500	22 500 000
Zamboanga	10	3 720	18 600 000
Palawan	9	3 600	18 000 000
Central Visayas	7	2 600	13 000 000
Others	2	1 000	5 000 000
Total	100	38 2202	191 100 000

Exports - raw materials + seaweed products

Typical seaweed farming family annual income

				Low	High
Average area cultivated				2 500 sq m	5 000 sq m
Annual harvest				6 000 kg	12 000 kg
Average price (/kilo)				5.00	5.00
		Gross income		30 000	60 000
Expenses:
	Labor4
	Nylon lines (100 k ×l00)		1 000
	Plastic straw		500
	Wood stakes (1000 ×0.20)		200
	Banca		1 000
	Daily subsistence:
	1 bag rice/mo, at 350		4 200
	Miscellaneous: (Fuel, etc.)		6 000	18 900	18 900
		Net income		11 100	41 000

¹ Tawi-Tawi provides about 60 percent total Philippine Eucheuma seaweed harvests.

² E. cottonii* — 36 300 mt;
E. spinosum** — 1 920 mt, average price is 5.00/kilo.

³ One kilo carrageenan extract is equivalent to 4.5 kilos raw.

⁴ Assume the family provides own labor.

NOTE: * Correct botanical name is Eucheuma alvarezii.
** Correct botanical name is E. denticulatum.

Private sector investments

Company	Plant	Location	Annual capacity (mt)	Investment (P)
Deltagen/Biocon	Crude carrageenan	Mandaue City, Cebu	400	10 000
Manwealth	Raw material	Mandaue City, Cebu	3 000	5 0001
Marcel	Crude carrageenan	Zamboanga City	1 500	15 000
	Refine carrageenan	Metro Manila	200	25 0002
	Raw material	Zamboanga City	6 000	5 000
MCPI	Crude carrageenan	Mandaue City, Cebu	2 000	30 000
Corporation	Refine carrageenan	-do-	500	50 0003
	Raw material	-do-	6 000	4 000
SHEMBERG	Crude carrageenan	Mandaue City, Cebu	2 000	25 000
	Refine carrageenan	-do-	400	60 000
	Raw material	-do-	6 000	5 000
Others	Crude carrageenan	Zamboanga City/Palawan
	Raw material	Tawi-Tawi	10 000	10 000
	Total			244 000

¹ Owners are from Tawi-Tawi.

² Construction in progress.

³ Designs in progress.

Carrageenan product export in 1986 is about 4 500 metric tons with an estimated value of US$14 400 000 (288 000 000), providing approximately 62 percent of the foreign exchange earnings of the seaweed industry. Usage of Philippine Semi-Refined Carrageenan (SRC) has been limited and unfairly restricted to pet foods, personal care and industrial application since it was banned as an acceptable additive in human foods during the recent meeting in Rome of the Joint FAO/WHO Experts Committee on Food Additives at the instigation of MARINALG, an association of carrageenan manufacturers from the industrialized countries.

Refined carrageenan from the Philippines was introduced into the market last year. About 100 metric tons of refined carrageenan has been exported to Europe and Japan.

Sargassum exports were mainly ground products for animal feed component in Japan. About 700 metric tons was exported in 1986 with an estimated value of $200 000 (1 400 000). China and Indonesia are providing formidable competitions.

5. POTENTIALS FOR DEVELOPMENTS

Eucheuma-based industries appear to be maturing. The 1986 large volume increase over the previous year was mainly due to inventory positioning of the foreign buyers as a hedge for a perceived political instability of the country last year. There is, however, potentials for Eucheuma as a fresh processed table food item similar to Nori or Wakami for both the local and international consumers.

Gracilaria and Gelidium have plenty of room for developments. Gracilaria is now successfully grown in Taiwan and efforts are underway in Thailand. The Philippines has suitable sites and technology is available.

Sargassum and other brown seaweeds have bigger potentials as animal feed component. Sargassum is abundantly available and cheap. Local feed millers could use Sargassum with very little processing.

A bright potential also is in the horizon for a polyculture system in the seaweed farms. Technology for growing mollusk and other marine species such as abalone, giant clams and cucumber are now emerging and compatible with seaweeds farming.

6. NEEDS/PROBLEMS/ISSUES AND RECOMMENDATIONS

The various sectors of the seaweed industry have formed together into an industry association in 1985. The common issue which the industry association is trying to resolve are wide variations in quality and stiff fluctuations in prices of the harvests.

As the industry matures, price of the produce remains at lower level thus, reducing the farmers income. Polyculture of seaweeds together with other marine species, therefore, needs adequate attention.

Majority of individual seaweed farms are still without license or concession from the Bureau of Fisheries and Aquatic Resources. The industry association is assisting the government on this aspect. BFAR should accelerate processing of applications.

The Philippines used to be the only Eucheuma farming country in Southeast Asia. In 1986, Indonesia started shipping in commercial quantities cultivated Eucheuma seaweeds at a very competitive price. Eucheuma farming in Indonesia was initiated by the major European and U.S. carrageenan manufacturers as a reaction to an attempt by the defunct Batasang Pambansa to create a Seaweed Industry Commission and as a hedge to earlier worsening political condition. The damage has been done, however, learning from this lesson, the government should now be more promotive rather than regulative on the industry.

Seaweed processing and exporting companies find Mandaue City (Cebu) the ideal place for their plants due to conducive investment climate and availability of comparatively better infrastructure facilities such as:

1. Local and international shipping ports
2. Communications: Telephone, telexes, etc.
3. Power and water
4. Banking facilities and government offices

5. Peace and order

7. INDUSTRY PROBLEMS

7.1 High variable raw material quality due to lack of post-harvest facilities.

7.2 Low farm productivity resulting to uncompetitive prices.

7.3 Excessive shipping and handling costs from the farming regions to the processing plants due to inadequate ports and transport facilities.

7.4 Lack of power and water facilities in the farming regions.

7.5 Lack of banking and communication facilities in the farming regions.

7.6 Peace and order threats in the farming areas.

7.7 Unruly competition both in local and international markets.

7.8 Emergence of Indonesia as a strong competitor in the world market.