On the mackerel fishery of the Mandapam area

Mackerel supports a minor fishery in the Mandapam area, especially along the Gulf of Mannar coast. The landings are, of course, small and cannot be compared with those on the West Coast. According to Krishnamurthi (1957), the total mackerel catch in Rameswaram Island in 1952-53 and 1953-54 amounted only to about 9-3 tons. He also found that among the important fishes there, mackerel occupied the 15th and 11th ranks respectively with regard to its contribution to tota catch and the monetary yield. However, the catch and financial returns are certainly much better on the mainland. Mackerel are rarely landed on the Palk Bay side where the general fishing season extends from April to October. However, in October 1956, unusually large catches were recorded on this coast also. During April-September there is little fishing activity on the Gulf of Mannar side. Fishing operations here extend from October-March and it is during this period that mackerel appear in the nearshore waters in sufficiently large numbers as to constitute an important fishery. This account deals with the observations conducted on the fishery from 1952-57 with special reference to catch-per-unit of effort, size composition and maturity

Criteria for fishery regulation

Fishery regulation is as complicated as life itself being concerned with the ordering of the lives of aquatic an imals useful to man. It is not entirely a modern activity but had been in vogue even in ancient times. in enlightened countries like India. Only intuition and common sense were the guiding factors then and regulation was often intended mainly to protect the spawners

On the oil sardine fishery of the Calicut area during the years 1955-56 to 1958-59

There were record catches of the oil sardine {Sardinella longiceps Val.) on the West Coast during the year 1957-58; the 1955-56 season had been poor while in 1956-57 the landings were moderate. The total landings in India from October 1957 to September 1958 amounted to about 238,631 metric tons {vide Quarterly Reports of the C.M.F.R. Institute), which represented the highest reported yield after the 1933-34 season. During 1957-58 was also witnessed an extension of the area of commercial abundance of the fish inasmuch as very good catches were reported even from centres outside the normal sardine zone. The 1958-59 season was however not as successful, and in Calicut was productive, but short. This paper deals with the fishery of the 1955-56 to 1958-59 seasons in the Calicut area, with special reference to catch, effort, surface salinity and temperature of sea-water and size- and age-composition of the landings

The accumulated stock

The concept of accumulated stock explains the fall and subsequent stabilisation , at a lower level, of the catch in an expanding fishery. When demand for a particular fish increases, the trade concentrates the effort on it.

Length-weight relationship in Sardinella albella (Val.) and Sardinella gibbosa (Bleek.)

The length-weight relationships in S. albella and S. gibbosa were estimated. In 5'. albella, the regression coefficients of the 20-39 mm group, the larger indeterminates of the 40-95 mm group and the sexes were found to be significantly different from one another and from 3. In S.gibboia, the regression coefficients of the 20-39 mm group and the larger fish (indeterminates of the 40-95 mm group and the sexes) were significantly different from one another and from 3. In both species, the regression coefficients of the fishes of the 20-39 mm group were significantly higher than those of the fishes of the larger size-groups

Variations in the Fat Content of the Muscles of the Ribbon Fish, Trichiurus haumela (Forskal)

Both the immature and maturing Trichiurus exhibit periodic variations in muscle fat value. These are partly detennined by changes in the quality and quantity of food consumed. Within certain limits, fat value increases with length. Changes in size-composition have some influence on the monthly fat values of the immature stock, but have no significant effect on those of the maturing group

On the South Kanara coastal fishery for mackerel, Rastrelliger canagurta (Cuvier) together with notes on the biology of the fish

North of Mangalore, the South Kanara fishery for the Indian mackerel, Rastrelliger canagurta (Cuvier), is confined mostly to coastal waters, the gear used is the Rampant net, a large shore-seine which exploits only a narrow belt of the sea \-\\ miles from shore [see Pradhan (1956) for description and figure of the net]. The use of other gear for mackerel during the season has traditionally been under a social ban in many of the fishing villages; but even in other places, where the ban does not exist, no serious attempts are made to extend the area of operations. Nevertheless, the output at these centres of coastal fishing forms a major contribution to the total mackerel catch in India. As in other sections of the coast, the best catches are obtained during the October- December period, though the sea&on, as a rule, begins in October and lasts until March or April. During other months, small quantities of mackerel are caught in gill-nets (Pattavala) and small shore-seines (Kairampanis); the gill-net boats venture to a distance of about 6 miles off"shore, while ' Kairampanis' are operated within a zone of only about half a mile from the shore. Panikkar (1949, 1952) has summed up the present state of our knowledge regarding the life-history and movements of mackerel, and has further indicated the lines of investigation that have to be undertaken for a fuller understanding of the fluctuations in catches. Recently Pradhan (1956) has published the results of his study of the mackerel fishery of Karwar. This paper deals with the coastal fishery of the region between Baikampady and Tarapathy in the South Kanara District, with special reference to that of Malpe, one of most important mackerel centres on the West Coast

The "Choodai"

The sardines, other than the oil sardine, though not so important as the latter nor as abundant, are of considerable local importance in that they are popular food fishes contributing to a seasonal fishery at some places along the east coast, especially the south «astern region. Due to their thin bodies and non-oily nature, they are conveniently and rapidly beach dried in large quantities and exported to interior places, in excess of local consumption in the fresh and cured states. Sordinella albella and S. jussieu are the two important species forming the fishery, others contributing only in a small measure to the fishery being S. sirm and S. c.lupeoides. In recent years (1960-1965) on an all India basis, these sardines which are together called "Choodai" in Tamil along the coast of Madras State, have contributed from 1.89 to 5.23 percent of the total marine fish catch

Observations on the choodai fishery of Mandapam area

In the economy of the fishing villages around Mandapam, there is probably no fishery of greater importance than that for sardines, locally called choodai. Beginning in late March or early April, the fishery extends up to October or November and is confined mainly to the inshore waters of Palk Bay, where specialised methods are employed for catching the juveniles. Devanesan (1932) has given a brief account of the food of Sardinella gibbosa, one of the species yielding the fishery; the bionomics and fishery of the same species have also been referred to in a note by Chacko (1946). Panikkar (1949), discussing the biology of the pelagic fishes of the world, has remarked on the occurrence of shoals of S. gibbosa on the South last coast of India. And recently, Prasad (1953) reporting on the swarming of Noctiluca in the Palk Bay, observed that this was responsible for the aet-back experienced by the choodai fishery early in the 1952 season. The salient features of the fishery, however, are as yet little understood, and this investigation, taken up at the suggestion of Dr. N. K. Panikkar, includes a study of the methods of fishing, the biology of the main species contributing to the fishery and the fluctuations in their abundance

On the food of the sardines, Sardinella albella (Val.) and S. Gibbosa (Bleek.) of the Mandapam area

That heterogeneous feeding relationship (Ivlev, 1961) in a sardine may be associated with the progressive development of gill rakers during ontogeny has become evident from the studies on the food of the Pacific sardine,Sardinops caerulea (Scofield, 1934) and the Japanese sardine, Sardinops melanosticta (Tokai Regional Fisheries Research Laboratory, 1960). This aspect has been referred to by other workers also (Larraneta, 1960) but not yet studied properly. A closely related problem is selective feeding, the investigation of which requires simultaneous collections of plankton and sardine samples, as borne out by the studies of Hand and Berner (1959) on the food of the Pacific sardine and of various workers on herring Calanus relationship (Gushing, 1955). But most of the investigations in this line have not fulfilled this condition