A STUDY OF ECOLOGICAL RESEARCH IN THE GEOGRAPHY OF FISHERIES: THE CASE OF THE USE PATTERNS OF THE FISHING GROUNDS FOR HAND-LINE FISHING (IPPON-ZURI) IN MUKUNA, THE OCHI ISLANDS

Abstract

This article attempts to examine the time and space use patterns of the fishing grounds for hand-line fishing in Mukuna, a village on the 4chi Islands of Ehime Prefecture from the ecological point of view. Using the results of a field survey, applicability of ecological researches on the fishing ground use the geography of fisheries is also investigated. Data were collected by direct observation of fishing activities on the sea, as well as by interviewing the fishermen. The results of the field survey are summarized as follows: 1. It is nagashi-ipponzuri or the drifting hand-line fishing technique that is adopted by M ukuna fishermen. Motorboats operated by one fisherman are put to use for hand-line fishing. 2. The hand-line fishing takes place all year round. The fishing season is, however, divided into two periods in accordance with the seasonality of the catch: from April to January the fishing of madai (Chrysophrys major) and suzuki (Lateolabrax Japonicus) is practiced, while the fishing of kasago (Sebastiscus marmoratus) and mebaru (Sebastes inermis) is complementarily carried out in February and March. 3. Several sorts of bait are employed according to the seasonal variation in availability, 4. There are about thirty boats for hand-line fishing in Mukuna. This number is seasonally reduced according to shifts in the local climate. Merely ten are in use when the water temperature reaches its peak in the hottest months of August and September and when the water becomes cold and rough in winter with the northwest monsoon. 5. Mukuna waters provide twenty-two fishing spots, which can be classified into three categories in terms of the tidal current conditions. a) fishing spots used at ebb current (ten) b) fishing spots used at flood current (ten) c) fishing spots used at both ebb and flood current (two) 6. Considering the tidal current conditions, a fisherman decides the type of fishing spot which is suitable and then chooses by turns some of the fishing spots within the same category. 7. The hand-line fishing is conducted from early morning to evening. 8. It is not possible to do hand-line fishing when the tidal flow is fast. Fishermen cannot avoid stopping their work at sea until the tidal current conditions turn favourable. Some fishermen go back to the land to take a rest when the tidal current conditions are bad. 9. Mukuna fishermen can perceive clearly enough where they are at sea through yamasate, a location-finding technique by visual triangulation which is based on the observation of counter movements of two or more mountains or islands seen from the sea. An application of yamatate enables the fishermen to grasp the speed and direction of the currents. When their location at sea is once confirmed, the fishermen understand such attributes of the fishing ground as range, water depth, morphology of the sea bed, and so on, because they are well equipped with a large amount of empirical knowledge of each fishing spot. The author analyzed the use of the fishing ground in Mukuna from the viewpoints of the time-use pattern and the space-use pattern. In terms of the time-use pattern, data on daily, m onthly, seasonal, and annual cycles must be collected according to the fishing activity: In terms of the space-use pattern, three-dimensional space.……the surface, the water, and the sea bottom …… has' to be grasped as a whole. The author is intended to carry on this ecological study on the fishing ground use by accumulating more data on the time and space use of the fishing grounds and to integrate the data for a comprehensive ecological analysis of the fishing villages using these fishing, grounds.