Organized marine fisheries research had already been carried out in central southern Brazil for many years when the associate expert arrived in 1963.
FAO technical assistance in marine fisheries research was initiated by the mission of Mr. Ripley (1955), followed by Mr. Devold (1956–57) and Mr. Richardson (1958–61). From 1960 to 1964 Mr. J. P. Wise and Mr. M. N. Mistakidis (1961–64) were working in the Three-Country Group Project.
All these missions had essentially the same aim; to advise the Government concerned on the research required for appraisal of their marine resources and to postulate methods of obtaining the largest sustainable yield without endangering these resources. Another important part of their mission was training local staff to continue such work.
The associate expert became involved in this work when he took up his duties with Mr. Wise in Santos. However, the duties of an associate expert are limited, and after Mr. Wise's departure from Santos, the associate expert restricted his activities mainly to technical matters. In practice this means that he was participating in local research.
During recent years sardine production in central southern Brazil has reached relatively high values. In Santos in 1964, sardine landings were 9,054 tons, representing 44 percent of all fish, shrimp and molluscs landed in Santos that year. For the State of Santa Catarina the figures were 9,375 tons and 54 percent respectively. It seems evident that sardine are an important marine resource off these parts of the Brazilian coast. Research for some years has already provided much data concerning sardine.
In estimating the size of the sardine stock and the effect of fishing on the stock it is valuable to consider the data in terms of age. Therefore, studies on age and growth, based on scale-readings, were already initiated by Richardson et al (1960). This work was continued during 1963–64. Scale readings for age from more than 4,500 sardines were analyzed and a growth rate was estimated by the method of back calculation. By means of graphical methods it was shown however, that rings counted on the sardine scale, in order to determine the age of sardine, most probably included some accessory rings. The results had therefore to be rejected. Later, a length-age relationship was determined based on the length-frequency distribution. (dos Santos and Frantzen 1965, in press) The results indicated that a sardine of a given length is in general one year older than suggested by Richardson and his collaborators.
Other recent works on sardine include condition factor analysis (K - values) in relation to sexual development and maturity stages (Vazzoler and Vazzoler, 1965, in press). At the Oceanographic Institute attempts have been made to “read” the otoliths of sardine for age determination; further, vertebrae countings are being made on juvenile and adult sardine from different localities to look for any relation which could indicate something about the possible presence of different populations. For the same purposes morphometric studies of sardine are under way. At the same Institute a study on the development of sardine from egg to adult is nearly completed. At both the Oceanographic Institute and at the SIPM investigations are being made on sardine maturity and fecundity.
In January 1964 research on sardine was started by the Fisheries Research Center in Florianópolis, Santa Catarina.
The project was initiated with a detailed collection of landing statistics in the most important fishing ports along the Santa Catarina coast. Data have also been collected on boats, gear, equipment and other factors. A biological sampling program commenced simultaneously. This program includes data on length, weight, sex-ratio, maturity and fecundity.
In June-July 1964 Mr. E. Tremel and FAO Master Fisherman Skapti Jonsson made a cruise in coastal waters north of Florianópolis, taking hydrographical stations, doing echo-surveying and fishing experiments with artificial light.
A first report on the sardine and the sardine fishery in Santa Catarina was completed in April-May 1965, (Tremel, Frantzen and Jonsson 1965). The report is mainly based on data collected during 1964, and gives information on total landings (by month), fishing areas, landings by areas and catch per unit of effort. It also contains some notes on sardine biology and a brief description of sardine fishing boats and gear.
A biological sampling program based on catches made by Japanese trawlers operating in Brazilian waters (furnished by the TAYO Company Limited) has been carried out for some years and is at present continued both at the SIPM and the Oceanographic Institute in Santos.
The last works comprise treatment of subjects such as:
Estimation of relative abundance of corvina off the coast of central southern Brazil (Vazzoler, 1965, in press).
Migrations of corvina in coastal waters off southern Brazil (Vazzoler and dos Santos, 1965, in press).
Relative spawning power of a pescada-foguete population from the southern coast of Brazil (Vazzoler, 1965, in press).
An analysis of the fishery on pescada-foguete in central-southern Brazil (Yamaguti and de Moraes, 1965, in press).
Migrations of pescada-foguete (dos Santos and Yamaguti, 1965, in press).
At the Oceanographic Institute investigations on maturity and fecundity for both species are continuing. As part of a research program on the possible occurrence of different populations, comparison of biological parameters, morphometric and genetic studies are also being carried out.
Two main kinds of shrimp are landed at Santos; sea-bob (camarão sete-barbas) and pink shrimp (camarão rosa). Neiva and Wise (1963) analysed landing statistics for sea-bob (mainly Xiphopenaeus kroyeri). At present a first analysis of data collected on pink shrimp (Penaeus brasiliensis and Penaeus aztecus) is being prepared by Neiva (1965, in preparation).
Some plankton samples have been examined to look for and determine larval stages of shrimp. One aim of this work, which probably will be continued, is to obtain knowledge about the spawning place and migrations of different types of shrimp.
Since July 1958 detailed landing statistics have been collected from fish markets in Santos. Such data include the following:
Name and size of boat
Type of fishing gear
Total quantity of fish, shrimps, and molluscs landed by each boat
Quantity of each species landed
Position of fishing ground
Number of days absent from port
Number of days actually spent fishing
Number of hauls
Duration in hours of each haul
The data were from the master or crew. In general there has been good collaboration between the fishermen and the people collecting data on behalf of the research group. A study carried out in 1964 demonstrated, however, that at that time, for many boats landing in Santos the data were incomplete and even false. Total landed weights tended to be underestimated. Discrepancies were also found in the data of fishing ground position, number of days spent fishing, number of hauls, and duration of each haul.
Such data are essential for any study of the effect of a fishery on the stocks of fish. Suggestions were therefore made for improvements in data collection and handling. It was found, however, that to improve the actual methods seems somewhat difficult, and the only solution is probably to make completely new arrangements in this part of the work.
In late 1964 work was initiated on a general review of the fishery of the Santos fleet during the years 1959–64. The work is based on the landing statistics collected at the fish markets in Santos, and gives brief information on various aspects of the Santos fishery (de Moraes, de Moraes, Neiva and Frantzen, 1965, in preparation).
The paper will deal with total landings, landings by species (for the most important), fishing area, boats, gear, etc. Important species such as “sardinha” (sardine) (Sardinella aurita), “pescada-foguete” (Macrodon ancylodon) and “goête” (Cynoscion petranus) (weak fish), “corvina” (croaker) (Micropogon furnieri) and “camaroes (shrimp) are considered somewhat in detail. Regarding these species, the information includes items such as relative fishable density (production/haul), areas of production of each species, fluctuations in relative density within and between areas and other data. Some biological observations can also be found for some species.
Paper partition chromatography used as a tool in the study of fish populations was introduced to members of the laboratory groups in Santos. From time to time during the last 18 months occasional experiments have been carried out in applying this method to shrimp, sardine and other species.
Unfortunately, it was only by the end of the associate expert's stay in Brazil that sufficient equipment became available to initiate a project using this method. At present a sardine project is under way at the SIPM, and so far the results are promising. Chromatograms of sardine taken in coastal waters off Santos appear clear and with a well-defined pattern. If this work can be continued and extended to include analysis from other localities, this probably can indicate whether or not the sardine stock outside central southern Brazil is composed of several populations.
At the Oceanographic Institute about 20 species have been examined. All experiments gave chromatograms which were different and specific for each species. It is planned that this Institute will apply this method in one part of its project in population studies of corvina and pescada-foguete.
Only one opportunity was given to participate in a short trip in coastal waters off Santos, doing echo-surveys, taking hydrographical stations and plankton samples. Later, Mr. G. Vazzoler made some echo-surveys in near coastal waters off the State of São Paulo on board the R/V Emilia.
The lack of an ocean-going fisheries research vessel does not permit work of any extent to be done in the open sea. The R/V Emilia, belonging to the Oceanographic Institute of the University of São Paulo, and the Gato of the Instituto de Pesca Marítima M. Nascimento Jr., are both small and can only be used inshore.
A new research vessel will now be constructed in Norway for the Oceanographic Institute of the University of São Paulo. The characteristics of this ship seem suitable for most of the work at sea.
