by
A. SREENIVASAN
Fresh-water Biological Station
Bhavanisagar, India
FISH PRODUCTION IN SOME RURAL DEMONSTRATION PONDS IN MADRAS (INDIA) WITH AN ACCOUNT OF THE CHEMISTRY OF WATER AND SOIL
Abstract
The hydrological features and fish yield in more than fifty ponds in Madras State were studied and the ponds classified on the basis of certain ecological conditions - fort moats, temple tanks, rock pools, coastal ponds, large irrigation tanks and village ponds. Waters having permanent silt turbidity gave very low annual fish yields of less than 150 kg/ha. Even though shallow, large irrigation tanks with continuous inflow and outflow yielded less than 100 kg/ha/annum because of poor plankton development. When electrical conductivity was over 400 μ mhos, it did not limit productivity, but above this value productivity did not increase proportionately with conductivity. Most of the ponds studied had a total alkalinity over 150 ppm, total hardness over 100 ppm, calcium over 30.0 mg/l and a pH over 7.0. Soils with “available phosphorus” less than 0.5 ppm, pH less than 7.0 and calcium less than 50 ppm were in the low productive group. The fort moats, temple tanks and rock pools were highly productive waters, having permanent blooms of blue-green algae. The milkfish Chanos chanos and other herbivorous fishes grew well in these. The fort moats and temple tanks yielded more than 1000 kg/ha/annum. Combined culture of Tilapia sp. with Chanos and carps resulted in decreased yield. In tilapia ponds, intensive cropping yielded over 2,000 kg/ha/annum, but these were of fish less than 50 g each in weight. Ponds stocked with more than 10,000 fish per ha (especially ‘major’ carps) gave a production of over 1,000 kg/ha/annum.
PRODUCTION DE POISSON DANS CERTAINS ETANGS RURAUX DE DEMONSTRATION A MADRAS (INDE) ET ETUDE CHIMIQUE DE L'EAU ET DU SOL
Résumé
Il a été procédé à une étude des caractéristiques hydrologiques et du rendement en poisson de plus de cinquante étangs de l'Etat de Madras, classés en fonction de certaines conditions écologiques en fossés de forts, bassins de temples, trous d'eau rocheux, étangs côtiers, grands réservoirs d'irrigation et étangs de villages. Les eaux présentant une turbidité permanente due à la présence de particules de limon en suspension fournissent une production annuelle de poisson très faible, de l'ordre de moins de 150 kg/ha. Bien que peu profonds, les grands réservoirs d'irrigation avec alimentation et écoulement permanents produisent moins de 100 kg/ha/année à cause du faible développement du plancton. Il a été constaté qu'une conductivité électrique supérieure à 400 μ mhos ne limitait pas la productivité, mais qu'au-delà de cette valeur celle-ci n'augmentait pas proportionnellement à la conductivité. Dans la plupart des pièces d'eau étudiées, l'alcalinité totale était supérieure à 150 ppm, la dureté totale supérieure à 100 ppm, la teneur en calcium supérieure à 30,0 mg/l et le pH supérieur à 7,0. Les sols les moins productifs étaient ceux ayant une teneur en “phosphore disponible” inférieure à 0,5 ppm, un pH inférieur à 7,0 et une teneur en calcium inférieure à 50 ppm. Il a été observé que les fossés de forts, les bassins de temples et les trous d'eau rocheux contenaient les eaux les plus productives et qu'il s'y trouvait en permanence des fleurs d'eau d'algues bleues. Le Chanos chanos et autres poissons herbivores prospèrent dans ces eaux. Les fossés de fort et les bassins de temples fournissent un rendement de plus de 1 000 kg/ha/année. L'élevage de Tilapia sp., de Chanos et de carpes dans la même pièce d'eau a eu pour résultat de diminuer le rendement. Dans les étangs à Tilapia, une exploitation intensive a permis d'obtenir des rendements dépassant 2 000 kg/ha/année, mais s'agissait de poissons pesant moins de 50 g chacun. Des étangs chargés à plus de 10 000 poissons à l'hectare (notamment des ‘major’ carps) ont fourni une production de plus de 1 000 kg/ha/année.
PRODUCCION DE PESCADO EN ALGUNOS ESTANQUES RURALES DE DEMOSTRACION DE MADRAS (INDIA) JUNTO CON UNA RESENA DE LA QUIMICA DEL AGUA Y EL SUELO
Extracto
Se estudiaron las características hidrológicas y el rendimiento en peces de más de 50 estanques del Estado de Madras, los cuales se clasificaron sobre la base de ciertas condiciones ecológicas, por ejemplo, fosos de fuertes, estanques de templos, balsas de rocas, lagunas costeras, grandes embalses de riego y estanques de poblados. Las aguas que tenían una turbidez permanente debida a los sedimentos daban unos rendimientos anuales de peces muy bajos, inferiores a 150 kg/ha. Pero, incluso los grandes embalses de riego de poca profundidad con entrada y salida contínua de agua rindieron menos de 100 kg/ha/anuales debido a la escasez de plancton. Cuando la conductividad eléctrica era superior a 400 μ mhos, esto no limitó la productividad, pero, por encima de dicho valor, la productividad no aumentó proporcionalmente con la conductividad. La mayoría de los estanques estudiados tenían una alcalinidad total de más de 150 ppm, una “dureza” del agua superior a 100 ppm, calcio por encima de 30,0 mg/l y un pH superior a 7,0. Los suelos con “fósforo disponible” en cantidad menor a 0,5 ppm, un pH inferior a 7,0 y con menos calcio de 50 ppm figuraban en el grupo de baja productividad. Los fosos de fuertes, los estanques de los templos y las balsas de las rocas eran aguas muy productivas que tenían floraciones permanentes de algas verde-azules. El sabalote (Chanos chanos) y otros peces herbívoros se criaban bien en estas aguas. Los fosos de los fuertes y los estanques de los templos daban un rendimiento superior a 1.000 kg/ha/anuales. El cultivo combinado de Tilapia sp. con Chanos y carpas dió por resultado una disminución del rendimiento. En los estanques dedicados a Tilapia, el cultivo intensivo rindió más de 2.000 kg/ha/anuales, pero consistente en peces de menos de 50 gramos de peso cada uno. Los estanques poblados con más de 10.000 indivíduos por hectárea especialmente carpas “principales”) dieron una producción superior a 1.000 kg/ha/anuales.
The Madras Fisheries Department pioneered the development of fisheries in rural areas, by establishing demonstration ponds in widely scattered parts of this State. There are more than a hundred such ponds of which more than half have been studied intensively with regard to their hydrobiological and edaphic conditions. Fish stocking and removals have also been recorded. Such complete details correlating fish yields with hydrobiological and soil conditions are not available for many other parts of the world. Hence the results of our studies are presented in this report.
Schuster et al., (1954) and Mortimer (1954) furnished comparative figures of fish production from a few selected countries, the ones noted for high yields being, Belgian Congo (2,000 kg/ha), Israel (1,650 kg/ha) and Indonesia (1,000 kg/ha). Recently production has increased in these and other countries. Sarig (1961) has recorded a yield of 1,550 to 2,270 kg/ha from Israel during 1960, which was an increase of 107 percent over the 1950 rate. Tal and Shelubsky (1952) reported that while in 1938, there were only ten ha of fish ponds in Israel, during 1950, it had increased to 3,000 ha yielding 5,000 tons of fish (1,700 kg/ha). Hurvitz (1960) records individual yields of 4,300 kg/ha from ponds in Heftsi-bah area of Israel. A striking increase of fish yield was reported by Prowse (1963) from Malaya, where a former production of 22.4 kg/ha in acidic cat-clay ponds was boosted to 1,680 kg/ha in three years by liming and application of superphosphate. Individual yields exceeded 2,200 kg/ha. By intensive feeding, 1,220 kg/ha carp were obtained from Eastern Germany (Schäperclaus, 1961a) and 2,548 kg/ha in Koncanica in Yugoslavia (Schäperclaus, 1961b), and 1,500 kg/ha in the Ukrainian Republic. (Michler and Schäperclaus, 1963). In Russia, net yields of 918 to 1,184 kg/ha of fish were obtained in ponds supplied with purified sewage, (Wolny, 1962). Timmerman (1960) reported a yield of 750 kg/ha in natural ponds in Lebanon which could be raised to 1,500 kg/ha by feeding. In Sudan, Huet (1959) noted a natural production of 500 kg/ha which could be raised to 2,500 kg/ha by intensive feeding. In the Congo, a yield of 4,325 kg/ha was normal in Kivu Province (Huet, 1957) but 70 percent of this was made up of Tilapia of sizes less than 15 cm. He also recorded the following yields - Katanga, 2,300 to 3,300 kg/ha; Orientale Province, 500 to 2,000 kg/ha, Ruanda-Urundi, 1,000 kg/ha and Equatoriale and Kasai Province 500 kg/ha. The Indonesian ponds produced 1,181 kg/ha, i.e., 24.139 tons in 20,441 ha (Huet, 1956). Combination of species increased the yield and supplemental feeding boosted the production to 5,000 kg/ha. Vaas (1948) had earlier noted that sewage-fertilized ponds yielded 3,009 kg/ha of carps. Staggering yields of 3,600 to 17,800 kg/ha were reported from Bangkhen farm in Thailand (Pongsuwana, 1957). Sreenivasan (1964) has described the ecology of ponds yielding over 1,000 kg/ha, one of them yielding over 5,000 kg/ha. In this paper, an account of fish production from over fifty ponds in the Madras State in India is discussed.
Water samples were collected and analysed according to standard methods. Most of the ponds were visited on more than five occasions. Data on free carbon dioxide and CO3 “were obtained but not included in Table I. Low bicarbonate values in some ponds is due to high CO3” values caused by intense photosynthesis in phytoplankton-rich waters. Nitrates and inorganic phosphate were present in very rare instances and are omitted from Table I. Soil testing was done by the Spurway (1944) method. In some soils, detailed analysis was done according to Piper(1950). Plankton was collected with a nylon net of 120 to 150 mesh/in (50 to 60 mesh/cm).
The ponds studied were divided into six types according to their use. They were (i) fort moats, (ii) temple tanks, (iii) rock pools, (iv) coastal ponds, (v) large irrigation tanks and (vi) other village ponds. The majority of the ponds had an area of 0.4 to 1.6 ha (one to four acres); only two tanks were over 50 ha.
The fort moats are excavated ditches around old forts, the rock walls of the fort forming one side of the ponds. The opposite side may also be a stone-built wall, as in Vellore fort moat, or merely a sloping earthern embankment as in Arni fort moat. The run-off water accumulates in these after rain and the perennial ones also have underground springs. These fort moat waters are virtually ‘derelict’, used only for washing cattle. Quite often the sewage from the town is let into these ponds, which act as 'sewage oxidation ponds" (Sreenivasan, 1964a). Heavy organic growths occur as blooms of blue-green algae. The bicarbonate (methyl orange alkalinity) content of these is very high, often over 200 ppm. In summer the phenolphthalein alkalinity is high and sometimes hydroxide alkalinity also ensues. High hardness and very high electrical conductivity (dissolved solids) also characterize these waters. The calcium and chloride content were not high, but the pH value was rather high (over 8.5). Fluctuations in dissolved oxygen were common, with very low values in the morning and supersaturation values in the afternoon, indicating the high metabolic rates caused by the activities of photosynthetic algae. A permanent bloom of blue-green algae all round the year was a characteristic of these waters, the dominant forms being Microcystis, Merismopedia, Oscillatoria, Nostoc, Spirulina, etc. Fairly abundant zooplankton also occurs in these ponds. Fishes grow well in these waters and when stocked with planktophagous species, good yields ensued. Chanos was found to fare well in the fort moat waters, a growth of at least 500 g/year being obtained. Bottom fauna was fairly abundant in these ponds, and fishes feeding at this trophic level (for example, Cyprinus carpio) grew well. Except in Arni fort moat, the fish yield has been over 1,000 kg/ha/annum. Because of excessive blooms of plankton, high rates of stocking with planktonfeeders like Chanos chanos, Cirrhina cirrhosa, C. mrigala, Catla catla, etc., gave good results. This is one way of removing the ever-increasing organic matter. Low rates of stocking have been futile. Fish mortalities may occur in these ponds, but this has not affected the final yields.
These are ponds paved with stones on the banks and gradually sloping towards the centre. The water is thus in contact with soil only for half its area. The temple tanks are not subject to sewage pollution, but are generally used for bathing and washing clothes. They have inlets to admit storm water but outlets rarely exist, or at best overflows exist at higher levels. The water stagnates over years and both organic matter and inorganic materials accumulate. These temple tanks are indistinguishable from fort moats in their chemical conditions. They have high methyl orange alkalinity, high hardness, high electrical conductivity, and moderately high calcium. The pH value is invariably high, reaching over 9.6. Diurnal fluctuations in dissolved oxygen, alkalinity and pH are common. Fish mortalities are recurrent in some of the temple tanks. Blooms of blue-green algae occur throughout the year, along with other groups such as Scenedesmus and in a few cases Botryococcus. Zooplankters are abundant too.
These “quarry” pools are formed by the excavation of rocks for building purposes and the pits formed get filled up by rains and by storm water. Silt settles in the course of time. In the absence of underground springs, the only source of water is precipitation and run-off from catchments. They have no inlets or outlets. Continued concentration of dissolved solids by evaporation results in a high chloride content and high electrical conductivity. The bicarbonate alkalinity is high, as in the fort moats and temple tanks. But the chloride, electrical conductivity, and pH are higher. Hardness was a little less than in those types of waters. Calcium content is fairly high. The plankton of these rock pools is similar to that in the fort moats and temple tanks, with blue-green algae dominating, the common genera in a bloom being Microcystis, Oscillatoria and Merismopedia.
These ponds are situated near the sea coast in deltaic areas. They receive supplies of fresh water and hence have a low chlorinity. The bicarbonate content is fairly high, as is also the hardness, which is higher than in rock pools and temple tanks. The electrical conductivity is very high, the high level of solutes being due to the saline influence. The pH is alkaline and calcium content is fairly high. These ponds develop dense growths of submerged weeds like Najas, Chara, Hydrilla, etc., and of emergents like Nymphaea and Nelumbium spp.
Two of these studied are small impoundments used for irrigation. Water from seepage channels or streams flows into the tanks (Odathurai and Ananthasagaram). After storage the water is used for irrigation of crops. There is a continuous inflow of water for about eight months a year and an outflow for a similar period. Algal blooms do not develop because the water is detained for only a short time, and due to the absence of pollution. One tank (Tamaraikulam) gets its water only from rain, and being shallow, has many submerged weeds. The other two larger tanks though very shallow are turbid and hence submerged weeds do not grow in them. The mean depth of Odathurai and Ananthasagaram is hardly 1.5 m.
This category includes all rural ponds not falling under the above five categories. All of the ponds are artificially created ones and used for bathing, washing clothes, etc. Only a few of them are polluted by human excreta and sewage, Chettikulam, Kumundankulam, Vairanachi Oorani, K.C. Kulam and Veppankulam. The ponds had fairly high bicarbonate, moderate hardness and fairly high electrical conductivity. Chlorinity was not high. The pH was not uniform in all the ponds, and varied widely, but most of them were on the alkaline side. Calcium content was not high in most of the ponds. There was no common feature in plankton composition and no two ponds were alike in this respect. Some of the ponds like Nathapallam, Chettinad moat described here, and Tirukkulam of Varappoor, and Nallathannikulam of Arni, are permanently turbid due to suspended inorganic matter and very little phytoplankton development takes place in these, and these are highly unproductive. Vellaikulam of Kancheepuram has a colloidal suspension causing turbidity.
Fifty-six ponds for which fairly adequate data on stocking and exploitation are available are dealt with in this paper. The figures furnished are the average of at least seven years data in most of the cases.
Ponds ranged in production from 45 kg/ha to 5,486 kg/ha. In Table III the ponds are arranged in four groups on the basis of annual yield. These categories are discussed below. Twenty ponds yielded more than 1,000 kg/ha. All these ponds had bicarbonate content over 180 ppm (as HCO3), and all except four had hardness (as CaCo3) exceeding 100. The majority of ponds in this category had calcium content of over 50 mg/l, while the electrical conductivity was generally over 500 μ mhos. Only one pond had electrical conductivity less than 200.
The second category which includes 13 ponds, yielded 500 to 999 kg/ha. In this group, the bicarbonate content was less than 180 ppm in the majority of ponds, but over 100 ppm in all but three ponds. The hardness was less than 100 ppm in half the ponds. Only in three ponds was the Ca over 50 ppm. The electrical conductivity was however high, due to chlorides.
In the third category are included 21 ponds yielding 100 to 499 kg/ha. The bicarbonate content in these was high and does not correlate with the fish yield. A few ponds had hardness less than 100 ppm, but the majority had a hardness over 100 ppm. The calcium content of most of the ponds was less than 50 mg/l. The electrical conductivity was high and not correlated with yield.
In the fourth category only three ponds with yield less than 100 kg/ha are included. Two of these have areas exceeding 100 acres (40 ha) though shallow (average depth only 1.5 m). All the three ponds are permanently turbid due to suspended inorganic matter.
In Table IV the soil nutrients of the ponds are tabulated according to decreasing levels of productivity, four categories being chosen. As seen in Table III, with regard to soil conditions, the first category had soils with available phosphorus over 0.75 ppm in the majority of ponds. The second category ponds also had similar phosphate contents. Contents of calcium, magnesium, ammonia, etc., were also similar. All these soils had a pH over 7.0 and many had a pH over 8.0. In the low productivity categories 3 and 4, the pH was lower and the phosphorus was not as high as in the other two groups. Low calcium is noticeable in some ponds in these categories.
From Table II it can be seen that stocking rates do influence the yield in ponds. Ponds in Tanjore district are well stocked with species such as Catla catla, Cirrhina mrigala, Labeo firmbriatus, Cirrhina cirrhosa, etc. Natural stocking from the river system also takes place. The reasons for high productivity in Webster moat, Tanjore, have been discussed by Sreenivasan (1960). Since some other ponds listed here are equally productive as judged by water quality, soil condition, etc., the high yield in Webster moat has to be ascribed to the high rate of stocking. This applies also to the other ponds of Tanjore district - West moat, Sengulam, Ayyankulam, Ayikulam, Pidarikulam, Anaiyadikulam, Tirukulam, etc. The fish yields in coastal ponds of Adirampatnam and Negapattinam are not very high in these the rate of stocking is low and the ponds are weed infested. It is of special interest that the chloride content of these ponds was low and so high chloride could not be the reason for the lower yields.
Kallukatti tank in Karaikudi, a ½ acre (0.2 ha) pond continuously yielded over 3,000 kg/ha. This is a typical Tilapia pond from which the catches consist of small-sized Tilapia of weights less than 35.0 g each. Economic fishes such as catla, Labeo sp., milkfish (Chanos) etc., did not thrive and grow well because of the severe competition from millions of Tilapia. Other ponds of similar Tilapia yields are Valaiveesi Teppam, Mariamman Teppam, K.C. Kulam, Vairanachi Oorani and the Pudokkottai ponds. In all these large numbers of small Tilapia make up the yield. Vellore fort moat and Ayyangulam, Tiruvannamalai are productive ponds which have given sustained yields of over 1,500 kg/ha and 1,400 kg/ha, respectively for many continuous years. It has been pointed out (Sreenivasan, 1964) that quite a high percentage of the primary production has been utilized in Vellore fort moat. Chinglepat fort moat, for all the high productivity, is too shallow (average depth 1.0 m) and this diminishes the carrying capacity. Growth of fish is however good. Tirukulam of Sirkali, shows a high yield of 1,800 kg/ha, but is made up of a large number of major carps of small size. The same result could have been achieved by lower stocking rates of major carps. In many ponds, yield of Chanos and major carps decreased after the introduction of Tilapia - Thearthankulam, Arni fort moat, etc.
The effect of size and depth of ponds is reflected in the three rock pools of Virdunagar, which are all very close to each other. Quarry pool I is shallow with an area of 0.45 acres (0.16 ha) and average depth of 1.5 m, and gives a yield of 797 kg/ha. Quarry pool II has an area of 0.65 acres (0.28 ha) and average depth of 2.0 m, and yields 489 kg/ha, while quarry pool III, having an area of 3.0 acres (1.2 ha) and average depth of 5 m, yields only 240 kg/ha. In all these ponds introduction of Tilapia ruined the culture of Chanos and major carps. Carlander (1951) recorded a catch of 1,235 lbs per acre (1,383.2 kg/ha) from 4.5 acre (1.8 ha) gravel pits. Deep temple tanks without shallow margins, for example Pallavankulam and Teppakulam of Sivaganga, also yield less, despite good chemical conditions of the waters. The two large irrigation tanks, Odathurai and Ananthasagaram gave very low yields of 67 and 56 kg/ha respectively. Though both are shallow, the vast area, the low stocking rate (with very few major carps), the wind induced turbulence causing water turbidity by bringing up the silt from the bottom, and the continuous inflow and outflow all contribute to the very low yields. Yount (1963) is of the opinion that aeration reduces productivity, by looking up the nutrients. Even this yield is mainly due to Tilapia (largesized ones), indigenous catfishes, and minor carps like Labeo fimbriatus and Cirrhina cirrhosa. Permanently turbid waters like Chettinad moat, Nallathannikulam, and Tirukulam of Varappoor give very low fish yields. Nathapallam, a similar pond in Pudukkottai yielded 150 kg/ha mainly through Tilapia, though catla did not thrive for want of plankton. Vellaikulam in Kancheepuram is also a turbid water which had fairly good zooplankton population but poor phytoplankton. Ganapati and Chacko (1951) recorded good growth of stray catla, but poor plankton growth restricts even moderate yields. The yield of 485 kg/ha in Chettinad ponds was the result of fertilization with inorganic fertilizers. Even intermittent fertilization with superphosphate has increased the yield from less than 150 kg/ha prior to 1962 to 485 kg/ha from 1963.
Wherever Tilapia has been combined with Catla and Chanos in productive ponds, the yield has been depressed and both Chanos and Catla could not be obtained in the catches. In overpopulated Tilapia ponds of Pudukkottai very intensive fishing for removal of Tilapia resulted in very high yields (similar to Kallukatti pond in Karaikudi).
Very few attempts have been made to classify fish ponds. Ganapati and Chacko (1950) made a tentative classification of fish ponds into five types and predicted the fish yields that could be obtained from each of these. Waters (1957) established a relationship between bicarbonate content of water and fish production. Ball (1948) similarly found a positive correlation between alkalinity and fish production, lakes with alkalinity over 150 ppm being highly productive. Barrett (1953) found that hard waters were more productive than soft waters and that phosphorus regeneration was better in waters of high alkalinity. Northcote and Larkin (1958) found that fish production was proportional to total dissolved solids. They found that a total dissolved solids content above 250 ppm produced abundant bottom fauna. Larger gill net catches were noted in lakes with total dissolved salts over 100 ppm. Dissolved nutrients must rank as a primary factor in determining levels of productivity. Soong Min Kong (1951) found that an alkaline reserve of 3.5 was optimum for fish production. A positive correlation between the methyl orange alkalinity content and the standing crop of fish was observed by Carlander (1955) and Slack (1955). Moyle (1954) observed that hard water lakes are more productive than soft water lakes, but suggests that calcium is not a critical factor in productivity. He used four indices, total phosphorus, total nitrogen, total alkalinity and salinity, to correlate with fish production. Chacko and Ganapati (1949) stated that a minimum of 650 ppm of calcium carbonate is essential for good fish production but this is erroneous because this level of alkalinity will be detrimental to fish. Hayes (1957) worked out a ‘productivity index’ for some Canadian lakes but he found no relationship between depth and productivity of bottom fauna.
In all the ponds studied by us, only four had bicarbonate alkalinity less than 100 ppm and only nine less than 150 ppm Only eight of the ponds had calcium less than 25 mg/l. With regard to hardness, all except two had more than 50 ppm hardness; most of the ponds had a hardness over 100 ppm. Only two ponds had electrical conductivity less than 250 μ mho. On the basis of alkalinity, Philipose (1960) divided fish pond waters into three categories and correlated these with the plankton production. However, when fish yield is one of the factors considered, his classification is not helpful. The ponds we have to deal with are all very ‘productive’ judged by soil and water conditions. The pH value alone would indicate this. Only one thing is clear, namely that permanently turbid waters carrying suspended inorganic or colloidal matter are very unproductive and yield less than 100 kg/ha. Stocking with Tilapia will slightly increase the yield.
Soils with ‘available phosphorus’ less than 0.5 ppm are definitely in the low productive group (<500 kg/ha). Those having phosphorus between 0.5 to 1.0 ppm are in the moderately productive group (500 to 1,000 kg/ha). Soils with available phosphorus of over 100 ppm are in the highly productive group (> 1,000 kg/ha). Soil calcium was low in the low productive groups, generally less than 100 mg/l, and soil pH values were comparatively low in this group.
From the results obtained in Madras ponds, no clear-cut and well-defined classification is possible. Most of the ponds appear to be chemically productive. One fact, however, is clear, ponds stocked with planktophagous and fast-growing fish such as Chanos chanos, Catla catla, Cirrhina mrigala, Labeo fimbriatus, Cirrhina cirrhosa, Labeo calbasu, etc., in large numbers give good yields. Some ponds with abundant phytoplankton failed to give high yields of fish because of poor stocking or due to mixing Tilapia with carps and Chanos. However, some ponds with Tilapia have given high yields when cropped intensively. The temple tanks, fort moats, rock pools and some rural ponds are highly productive of fish although no artificial feed is given, because of direct or indirect organic pollution. Fish is one form in which this stock of nutrients could be removed (Yount, 1963). The only ponds which were fertilized were the unproductive Chettinad ponds where occasional applications of superphosphate boosted the yield more than four times. For unfertilized and unfed fish ponds the production recorded for most of the ponds in this paper is fairly high.
Thanks are due to Mr. H.K. Ghazi, former Director of Fisheries, Madras, for suggesting this work and encouragement. I am also indebted to Mr. N.V. Choodamani for constant discussions and encouragement. Many officers of the Fisheries Department were kind enough to furnish data on fish stocking and yields.
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Table I
Chemical conditions in the rural fishery demonstration ponds
| 1 | Area of water (ha) 2 | Bicarbonates ppm 3 | Hardness as Ca(O3 ppc 4 | Electrical conductivity μ mho. 5 | Chloride ppm 6 | pH | Dissolved oxygen mg/l 8 | Calcium mg/l 9 | Location 10 | |
| A. Fort moat ponds | ||||||||||
| Vellore fort moat | 4.9 | 30.5–256.2 | 166–490 | 1125–2500 | 118–560 | 8.8–9.6 | 1.7–27.0 | 47.6-27.0 | Vellore, N.Arcot District | |
| Webster moat | 1.6 | 102.0–220.0 | 114–170 | 695 | 52–180 | 7.3–9-5 | 0.1–12.4 | 36.0–61.5 | Tanjore, Tanjore District | |
| Chinglepat fort moat | 2.4 | 152.5–432.0 | 113–350 | 630–1150 | 80–124 | 7.9–8.7 | 2.0–16.6 | 20.8–34.1 | Chinglepat, Chinglepat Dist | |
| Arni fort moat | 2.4 | 107.0–256.0 | 150–228 | 610–1900 | 160 | 9.3 | 4.8–5.2 | 25.5 | Arni, N. Arcot District | |
| West moat | 0.8 | 92.0–183.0 | 104 | 490-375 | 74–91 | 7.2–7.5 | 0.7 | 52.1 | Tanjore, Tanjore District | |
| B. Temple tanks | ||||||||||
| Mariamman Teppam | 6.9 | 451.0-156.0 | 182–200 | 2650 | 298–388 | 8.7–9.6 | 0.9–4.4 | 61.1 | Madurai, Madurai district | |
| Sarvatheertham | 1.6 | 98.5–214.0 | - | 460 | 86–310 | 8.9 | 0.7–9.5 | 33.6 | Kancheepuram,Chinglepat " | |
| Ayyangulam-Tiruvannamalai | 1.6 | 217.0–226.0 | 66.300 | 800–1350 | 220–320 | 7.6–9.6 | 5.5–15.6 | 43.8 | North Arcot district | |
| Teppakulem-Sivaganga | 2.4 | 104.0–201.0 | 80 | 900 | 160 | 7.4–8.8 | 0.0–1.3 | 34.1 | Ramnad district | |
| Tirukulam-Sirkali | 0.4 | 189.1 | 92 | 380 | 48 | 7.5 | 0.5 | 4.7 | Tanjore district | |
| Pallavankulam | 0.5 | 97.6–176.0 | 50–90 | 170–375 | 36–74 | 7.7–8.8 | 3.8 | 95.2 | Pudukkottai, Trichy district | |
| Ayyankulam-Tanjore | 0.8 | 88.5–220.0 | 104 | 490 | 74–91 | 7.2–7.5 | 0 | 52.1 | Tanjore district | |
| Anaiyadikulam | 0.4 | 378.2–607.2 | 290–360 | 1950 | 390 | 8.8–9.2 | 2.9–9.4 | 21.4 | Tanjore, Tanjore district | |
| Kallukatti Tank | 0.2 | 101.0–183.0 | 120–154 | 475 | 111–244 | 7.1–9.6 | 0.0–15.5 | 26.2–36.0 | Karaikudi, Ramnad district | |
| Sengulam | 1.6 | 116.0–281.0 | 144–170 | 890 | 62–156 | 7.3–8.3 | 6.5 | 19.6–46.1 | Mannargudi, Tanjore " | |
| C. Rock pools | ||||||||||
| Virudunagar | ||||||||||
| Quarry pool I | 0.16 | 167.8 | 70 | 2125 | 536 | 9.0 | 9.8 | 44.1 | Virudunagar, Ramnad " | |
| Quarry pool II | 0.28 | 326.0 | 34 | 3000 | 916 | 9.2 | 5.2 | 34.1 | " " " | |
| Quarry pool III | 1.20 | 219.6 | 134 | 725 | 116–130 | 8.3 | 6.0 | 34.1 | " " " | |
| Rettaikulam | 0.7 | 184.0–186.0 | 40.79 | 290–1675 | 61–400 | 8.6–9.5 | 6.0–9.2 | 135.2 | Pudukkottai, Trichy " | |
| Periakulam | 1.1 | 76.3–242.0 | 222 | 3000 | 216–1050 | 9.35 | 7.4 | 69.8 | " " " | |
| D. Coastal ponds | ||||||||||
| Katcheri pond | - | 107.0–122.0 | 136–147 | - | 104 | 8.0 | 4.9 | - | Nagapattinham, Tanjore " | |
| Eachangulam | 0.8 | 107–122 | 122–148 | 3000 | 1062 | 7.8–8.6 | 5.2–7.4 | nil | " " " | |
| P.M.Nadar pond | 0.8 | 238–553 | 312–466 | 1850 | 360 | 9.6 | 4.7–8.4 | 31.1 | " " " | |
| Aladikulam | 1.2 | 140–220 | 41–96 | 600 | 96–116 | 8.1–8.7 | 0.6–4.4 | 112.2 | Adirampatnam, " " | |
| Chekkadikulam | 1.5 | 186–378 | 98–124 | 1275 | 96–274 | 8.1–8.3 | 1.5–4.8 | 80.2 | " " " | |
| Pillaikulam | 2.6 | 177.421 | 88–116 | 1350 | 268–272 | 8.1–8.6 | 0.8–4.6 | 86.2 | " " " | |
| Patraikulam | 3.2 | 104 | 96 | - | 84 | 8.7 | 6.6 | - | " " " | |
| E. Large irrigation tanks | ||||||||||
| Odathurai tank | 60 | 112.9–576.0 | 16–284 | 410–500 | 21.6–72.0 | 8.8 | 6.6 | 26.8–28.4 | Coimbatore district | |
| Ananthasagaram tank | 45 | |||||||||
| Tamaraikulam | 6.7 | 162.0–293.0 | 122–134 | 800–1025 | 104–220.0 | 8.3–8.5 | 3.2–9.2 | 28.1–36.1 | Tiruvannamalai, N.A.district | |
| F. Other village ponds | ||||||||||
| Pidarikulam | 0.8 | 133–729 | 71 | 1810 | 90–224 | 7.5–8.1 | 1.1–3.7 | 7.8–8.0 | Tiruvannamalai, Kumbakonam, Tanjore district | |
| Ayikulam | 0.4 | 171–223 | 90–144 | 380 | 22–30 | 7.5–8.8 | 0.9–12.8 | 43.4 | -do- | |
| Baburajapuram pond | 0.4 | 201–207 | 126–201 | 320 | 46–198 | 7.5–7.6 | 2.7–3.6 | 32.1 | -do- | |
| Chettikulam | 1.1 | 33.6–129 | - | 495 | 95–152 | 8.4–9.6 | 7.6–13.8 | 33.2 | Kancheepuram, Chinglepat " | |
| Tirumakulam | 1.6 | 112.5–201 | - | 620 | 47–98 | 7.9–8.2 | 1.4–6.1 | 98.6 | Madurai | |
| Valvaiveesi Teppam | 0.3 | 500 | 1750 | 1750 | 330–375 | 8.5 | 4.9 | 92.6 | Madurai | |
| Masinagudi tank | 1.6 | 73.2–339 | 62–220 | 170–600 | 48.0 | 6.4–8.5 | 1.8–6.8 | 35.8–40.1 | Nilgiri district | |
| Vellaikulam, Arni | 0.08 | 91.5–97.6 | 76–84 | 320 | 52–82 | 7.5–8.6 | 2.1–3.0 | - | Arni, North Arcot district | |
| Theerthankulam | 1.2 | 54.9–176.8 | 188.270 | 625–3800 | 141–174 | 7.3–9.2 | 1.0–8.8 | 38.8 | Tindivanam, South Arcot | |
| Kumundankulam | 0.6 | 45.8 | 72 | 385 | 69–82 | 8.8–9.1 | 0.8 | 92.2 | Pudukkottai, Trichy district | |
| Kilnainar Eri | 0.5 | 30.5–400 | 74.92 | - | 88–110 | 7.15–9.2 | 0.0 | - | -do- | |
| Palanaiandi Oorani | 0.5 | 156.0–180 | 100–138 | 320–1025 | 80–224 | 7.3–8.8 | 3.2–7.2 | 57.1 | -do- | |
| Servaroyankulam | 0.4 | 278.0–308 | 134–184 | 2225 | 76–664 | 8.3 | nil | 2.6 | -do- | |
| Vairanachi Oorani | 0.3 | 424 | 282 | - | 349 | 8.5 | - | -do- | ||
| Rajakulam | 0.8 | 159–358 | 60.84 | 330–760 | 80.144 | 7.1–9.6 | 0.0–20.4 | 12.0 | -do- | |
| Nathappallam | 0.6 | 103.7 | 76 | 220 | 120 | 6.8–7.1 | 1.2 | Tr | -do- | |
| Melnainar Eri | 1.6 | 85.4 | 280 | 2100 | 564 | 7.9 | 0.0 | 44.1 | -do- | |
| Holdsworth Park Pond | 0.4 | 128.0 | 81 | 300 | 21.4 | 9.4 | 21.4 | - | -do- | |
| Vengappier Oothu | 0.3 | 184.0 | 36.0 | 250 | 86.0 | 7.6 | 8.6 | - | -do- | |
| K.C.Kulam | 0.6 | 119–250 | 170–216 | 820 | 116–250 | 7.9–8.2 | 1.4–6.1 | 50-8 | Chinglepat district | |
| Thimmarajakulam | 0.6 | 149.5–157.5 | - | 630 | 50.0 | 7.3–8.4 | 3.3–8.2 | 45.4 | -do- | |
| Veppankulam | 0.4 | 0.0–103.7 | - | 500 | 54–300 | 8.8–9.5 | 0.6 | nil | -do- | |
| Chettinad ponds | 0.4 | 49.2–132.0 | 50–70 | 225–325 | 36–75 | 6.9–7.5 | 1.4–9.4 | 17.0–21.0 | Chettinad, Ramnad district | |
| Chettinad moat | 0.8 | 48.0–91.2 | 76 | 175–241 | 64–83 | 6.6–7.9 | 6.5–8.8 | 30.3 | -do- | |
| Sandaimedu tank | 0.3 | 183–224 | 87.96 | 425–470 | 60 | 7.7 | 2.1–11.0 | 24.0 | Chengulam, North Arcot | |
| Thenpadikulam | 0.8 | 280.6 | 140 | 520 | 62 | 7.5 | 2.6 | 35.4 | Sirkali, Tanjore | |
Table II
Stocking rates and fish yields in Madras ponds
| Name of pond 1 | Stocking rate No./ha 2 | Species exploited (in the order of dominance) 3 | Yield kg/ha/year 4 | |
| 1. | Webster moat | 95,000 | Major carps, Labeo and Cirrhina spp. Tilapia, Chanos | 5,486 |
| 2. | Kallukatti tank | 25,000 | Entirely Tilapia (Small-sized) | 3,481 |
| 3. | West moat | 16,500 | Major carps, Labeo and Cirrhina spp. Tilapia, Chanos | 3,353 |
| 4. | Sengulam | 6,230 | Labeo and Cirrhina spp., Catla, Chanos, Tilapia | 2,770 |
| 5. | Anaiyadikulam | 12,500 | Major carps, Labeo and Cirrhina, Chanos | 1,638 |
| 6. | Tirukulam, Sirkali | 16,750 | Carps, Catla, mrigal, Chanos | 1,810 |
| 7. | Vellore fort moat | 16,750 | Chanos, carps, indigenous catfishes | 1,580 |
| 8. | Tirumkulam | 8,750 | Carps, Tilapia, Catla | 1,516 |
| 9. | Ayyankulam (Tanjore) | 17,750 | Chanos, carps, Catla | 1,514 |
| 10. | K.C.Kulam | 3,000 | Tilapia | 1,483 |
| 11. | Mariamman teppam | 2,100 | Tilapia | 1,473 |
| 12. | Ayikulam | 15,000 | Labeo and Cirrhina spp., murrels Chanos, Catla, mrigal | 1,420 |
| 13. | Pidarikulam | 11,000 | Major carps, Labeo and Cirrhina, Chanos | 1,420 |
| 14. | Ayyankulam (Tiruvannamalai) | 13,500 | Chanos, carps, Catla, Tilapia | 1,395 |
| 15. | Vairanachi oorani | 8,500 | Tilapia | 1,334 |
| 16. | Sandaimedu tank | - | Chanos, carps, Tilapia | 1,309 |
| 17. | Kilnainar eri | 22,500 | Tilapia mostly | 1,189 |
| 18. | Servaroyankulam | 13,000 | -do- | 1,148 |
| 19. | Palaniandi oorani | 12,000 | -do- | 1,126 |
| 20. | Rettaikulam | 1,325 | -do- | 1,020 |
| 21. | Chinglepat fort moat | 10,000 | Carps, Chanos, Tilapia, murrels | 888 |
| 22. | Baburajapuram tank | 7,500 | Carps, Chanos | 885 |
| 23. | Kudundankulam | 17,500 | mainly Tilapia | 845 |
| 24. | Quarry pool I | 13,500 | Tilapia, Chanos, carps | 797 |
| 25. | Pattraikulam | 3,250 | Catla, Labeo, Cirrhina, Chanos | 708 |
| 26. | Pallavankulam | 5,000 | Catla, carps | 689 |
| 27. | Vellaikulam, Arni | 9,450 | Tilapia | 685 |
| 28. | Melnainar eri | 4,700 | Tilapia | 651 |
| 29. | Theerthankulam | 12,000 | Tilapia mainly, carps and Chanos | 649 |
| 30. | Thimmarajakulam | 2,500 | Tilapia mainly, carps and Chanos | 599 |
| 31. | Aladikulam | 5,000 | Labeo and Cirrhina spp, Catla | 578 |
| 32. | Chettikulam | 8,750 | Tilapia, carps | 540 |
| 33. | Kachangulam | 5,140 | Catla, Labeo, mrigal, Cirrhina cirrhosa | 530 |
| 34. | Quarry pool II | 7,500 | Tilapia mainly, Labeo and Cirrhina | 489 |
| 35. | P. M. Nadar tank | 3,730 | Catla, Labeo, Cirrhina cirrhosa | 468 |
| 36. | Holdsworth park pond | 2,750 | Tilapia | 470 |
| 37. | Thenpadikulam | 10,500 | Catla, carps, Chanos | 457 |
| 38. | Chettinad ponds | 11,000 | Carps, Tilapia | 485 |
| 39. | Vengappier oothu | 23,750 | Tilapia mainly | 484 |
| 40. | Valaiveesiteppam | 7,250 | Tilapia | 461 |
| 41. | Masinagudi tank | 550 | Cyprinus carpio only | 397 |
| 42. | Periakulam | 8,000 | Tilapia mainly | 347 |
| 43. | Chekkadikulam | 1,125 | Carps, Catla, Tilapia | 336 |
| 44. | Sarvatheertham | 10,500 | Tilapia, Chanos, carps | 321 |
| 45. | Veppankulam | 11,000 | Tilapia mainly | 328 |
| 46. | Tamaraikulam | 3,750 | Tilapia, murrels, carps | 311 |
| 47. | Pillaikulam | 1,875 | Carps, Catla | 279 |
| 48. | Arni Fort Moat | 1,875 | Tilapia, carps, Chanos | 269 |
| 49. | Teppakulam, Sivaganga | 3,000 | Catla, Labeo and Cirrhina, Tilapia Chanos, murrels | 243 |
| 50. | Quarry pool III | 7,500 | Tilapia mainly, Chanos | 240 |
| 51. | Rajakulam | 6,000 | Tilapia mainly | 175 |
| 52. | Nathappallam | 2,250 | Tilapia mainly | 150 |
| 53. | Vellaikulam, Kancheepuram | 1,750 | Carps | 100 |
| 54. | Odathurai tank | 1,250 | Tilapia, Cirrhina and Labeo spp | 67 |
| 55. | Ananthasagaram tank | 1,750 | Tilapia mainly | 56 |
| 56. | Chettinad Moat | 1,000 | Carps, Tilapia | 45 |
Table III
Fish production in the ponds and certain chemical parameters
| Name of pond 1 | Bicarbonate HCO3 ppm 2 | Hardness (CaCO3) ppm 3 | Calcium ppm 4 | Electrical conductivity ppm 5 |
| I(a) 3,000 kg/ha | ||||
| Webster moat | 102–220 | 114–170 | 48–54 | 695 |
| West moat | 92–183 | 104 | 52.0 | 490 |
| Kallukkatti tank | 101–183 | 102–154 | 26.2–35.0 | 475 |
| (b) 1,000 kg/ha | ||||
| Sengulam | 116–281 | 144–170 | 19.6–46.1 | 890 |
| Tirukulam, Sirkali | 189 | 92 | 4.7 | 380 |
| Amaiyadikulam | 378–607 | 290–360 | 21.4 | 1950 |
| Vallore fort moat | 256 | 166–490 | 48–54 | 1125–2500 |
| Tirumakulam | 113–201 | - | 98-06 | 620 |
| Ayyankulam, Tanjore | 220 | 104 | 52.1 | 490 |
| K.O.Kulam | 119–250 | 170–216 | 50.8 | 820 |
| Mariamman teppam | 156–451 | 182–200 | 61.1 | 2650 |
| Ayikulam | 171–223 | 90–144 | 43.4 | 380 |
| Pidarikulam | 133–729 | 71 | 78.8 | 1810 |
| Ayyangulam (T.V.malai) | 217–226 | 66–300 | 43.8 | 800–1350 |
| Vairanachi oorani | 424 | 282 | - | - |
| Sandaimedu tank | 189–224 | 87–97 | 24.0 | 425–470 |
| Kilnainar eri | 400 | 74–92 | - | - |
| Servaroyankulam | 278–308 | 134–184 | nil | 2225 |
| Palaniandi oorani | 184–186 | 40–79 | 135.2 | 290–1675 |
| II. 500–999 kg/ha | ||||
| Chinglepat fort moat | 152.5–432 | 113–550 | 21–34 | 630–1150 |
| Baburajapuram tank | 201–207 | 126–301 | 32 | 320 |
| Kumundankulam | 46 | 72 | 92.2 | 385 |
| Quarry pool I | 167.8 | 70 | 44.1 | 2125 |
| Pattraikulam | 104 | 96 | - | - |
| Pallavankulam | 98–176 | 50–90 | 95-2 | 170–375 |
| Vellaikulam, Arni | 91.5 | 76 | - | 320 |
| Melnainar eri | 85.4 | 280 | 44.1 | 2100 |
| Theerthankulam | 177 | 188–207 | 39 | 625–3800 |
| Thimmarajakulam | 150–157 | - | 45.4 | 630 |
| Aladikulam | 140–219 | 41–96 | 112-2 | 600 |
| Chettikulam | 129 | - | 33.2 | 495 |
| Eachangulam | 107–122 | 122–148 | nil | 3000 |
| III. 100 to 499 kg/ha | ||||
| Quarry pool II | 326 | 34 | 34.1 | 3000 |
| Chettinad ponds | 49.2–132 | 50–70 | 17–21 | 225–325 |
| Vengappier oothu | 184 | 36 | - | 250 |
| Holdsworth park pond | 128 | 81 | - | 300 |
| P.M. Nadar tank | 238–553 | 213–446 | 31.1 | 1850 |
| Valaiveesi teppam | 500 | - | 92.6 | 1750 |
| Thenpadikulam | 281 | 140 | 35.4 | 520 |
| Masinagudi tank | 73.2 | 62–220 | 35.4 | 520 |
| Periakulam | 76–242 | 222 | 69.8 | 3000 |
| Chekkadikulam | 186–378 | 98–124 | 80.2 | 1275 |
| Veppankulam | 0.0–103.7(OH') | - | nil | 500 |
| Sarvatheerthan | 98.5–214 | - | 33.6 | 460 |
| Tamaraikulam | 162–293 | 122–134 | 28.1–36.1 | 800–1025 |
| Pillaikulam | 177–241 | 88–116 | 86.2 | 1350 |
| Arni fort moat | 107–256 | 150–228 | 25.5 | 610–1900 |
| Teppakulam (Sivaganga) | 104–201 | 80 | 34.1 | 900 |
| Quarry pool III | 219.6 | 134 | 34.1 | 725 |
| Rajakulam | 0.0–358(OH') | 60–84 | 12.0 | 330–760 |
| Nathapallam | 103.7 | 76 | Tr | 220 |
| Vellaikulam (Kancheepuram) | 180–247 | - | 65.3 | 805 |
| IV. Less than 100 kg/ha | ||||
| Odathurai tank | 113–576 | 284-166 | - | 410–500 |
| Ananthazagaram tank | 262.3 | - | 31.6 | 525 |
| Chettinad moat | 48.92 | 76 | 30.3 | 175–241 |
Table IV
Soil nutrients in the fish ponds
| 1 | Phosphate (available) ppm 2 | Calcium ppm 3 | Magnesium ppm 4 | NH3 ppm 5 | Organic nic matter% 6 | pH 7 |
| Webster moat | 1–2.5 | 10–20 | 2–6 | 0–25 | 1.9–3.1 | 7.2–8.0 |
| Kallukati tank | 0.5 | 40 | 6 | 10 | 8.48 | 8.0 |
| West moat | 0.25 | 100 | - | 10 | 11.3 | 8.0 |
| Seagulam | Tr | 20 | 2 | nil | 7.4 | |
| Anaiyadikulam | 1.0 | 20–150 | 6.8 | 2–15 | 10.8 | 7.2–8.0 |
| Vellore fort moat | 0.5–1.0 | 100–200 | 6 | 0–10 | 5.8 | 7.0–8.0 |
| Tirumakulam | 0.5–2.5 | 40–150 | 4.8 | 2 | 0.5 | 8.0 |
| Tirukulam (Sirkali) | 0.75 | 40 | 6 | 15 | 7.0 | |
| Ayyankulam (Tanjore) | 0.25 | 150 | nil | 10 | 8.0 | 7.5 |
| K.C.Kulam | 1.0–2.0 | 20–100 | 4 | nil-25 | 7.5–8.0 | |
| Mariamman tappam | 0.5–1.0 | 40–150 | 6–8 | 2–10 | 0.4 | 8.0 |
| Ayikulam | 0.5–2.5 | 20–40 | Tr-8 | 2–10 | 7.8 | 7.4–8.0 |
| Pidarikulam | 0.75–0.5 | 40–100 | 4 | 25-Tr | 7.8 | |
| Ayyangulam (Turuvannamalai) | 0.5 | 20 | 0.0–6 | 2–10 | 0.6 | 7.2–8.0 |
| Sandaimeda tank | 1.0 | 40 | 4 | 2 | 7.8 | |
| Servaroyankulam | 1.0 | 200 | 6 | 2 | 8.0 | |
| Palaniaadi oorani | 0.5 | 200 | 4 | 10 | 8.0 | |
| Rattaikulam | 0.5 | 20 | 4 | 2 | 8.0 | |
| Chinglepat fort moat | 0.5–2.0 | 20 | 4–6 | 25-2 | 8.0 | |
| Baburajapuram tank | 0.5–1.0 | 20–40 | Tr-6 | Tr | 7.8 | 7.0–7.5 |
| Quarry pool No.I | 0.5–1.0 | 100–150 | 2–6 | Tr-2 | 8.0 | |
| Pallavankulam | 0.5 | 20 | 4 | 2 | 8.0 | |
| Melnainar eri | 0.5 | 150 | 6 | 2 | 8.0 | |
| Theerthankulam | 0.5–1.0 | 20–200 | 6–10 | 10–25 | 15-5 | 7.6–8.0 |
| Thimmarajakulam | 0.5 | 100–200 | 2.12 | 0.200 | 7.5–8.0 | |
| Aladikulam | Tr | 150 | 6 | 10 | 7.2 | |
| Chettikulam | 0.5–2.5 | 20–100 | 4.12 | 2–25 | 8.0 | |
| Eachangulam | 0.5 | 20 | 4 | 15 | 7.2 | |
| Quarry pool No.II | 0.5 | 100–150 | 6–8 | Tr-10 | 8.0 | |
| P.M.Nadar tank | 0.5 | 2.0 | 4 | 10 | 6.8 | |
| Thenpadikulam | 0.75 | 20 | 4 | 25 | 7.0 | |
| Chettinad pond | 0.5–0.75 | 20–100 | 2.4 | Tr-25 | 8.04 | 6.7–7.0 |
| Valaiveesi teppam | 0.5–1.0 | 40–150 | 6–8 | 2–10 | 0–4 | 8.0 |
| Masinagudi tank | 0.5–1.0 | 20 | 1–6 | 0–10 | 12.1–19.3 | 6.6–7.5 |
| Chekkadikulam | Tr | 40 | 6 | nil | 7.6 | |
| Veppankulam | 0.5 | Tr-5 | 4 | 2–10 | 7.5–8.0 | |
| Tamaraikulam | 0.5 | 10–40 | 6 | 2 | 7.4–8.0 | |
| Pillaikulam | Tr | 20 | 2 | nil | 7.2 | |
| Arni fort moat | 0.75 | 100 | 6 | 10 | 8.0 | |
| Quarry pool No.III | 0.5 | 150 | 6 | 2 | 8.0 | |
| Rajakulam | 0.5 | 100 | 4 | 25 | 7.2 | |
| Nathapallam | 0.5 | 2 | 6.8 | |||
| Vellaikulam | ||||||
| (Kancheepuram) | 0.5 | 20–80 | 4–6 | 2 | 8.0 | |
| Odathurai tank | 0.5 | 20 | 8 | 0–10 | 0.25 | 6.8–8.0 |
| Ananthasagaram tank | 0.5 | 20 | 6 | 0–10 | 1.01 | 6.8–8.0 |
| Chettinad moat | 0.5–0.75 | 20–100 | 2.6 | nil | 6.0–7.0 |
