Showing papers on "Fishing published in 1976"

The Effect of Fishing on the Marine Finfish Biomass in the Northwest Atlantic from the Gulf of Maine to Cape Hatteras

Abstract: Relationships between fishing eftort, total finfish community biomass, and yield are determined using data on finfish biomass measured by research vessel trawl surveys and commercial catch and effort statistics. Combined individual species stock assessments and the Schaefer (1954) equilibrium yield model are utilized to estimate potential yields. The fishing effort of different gear types are combined to provide a standardized index of fishing effort in terms of days fished as reported to the International Commission for the Northwest Atlantic Fisheries (lCNAF). A multiplicative learning function is applied as a correction factor to reported days fished of newly developing fisheries, i.e. those deployed in areas and on stocks not previously fished. This correction factor adjusts data of fleets entering a fishery to the level of efficiency achieved by the third year in the fishery. These analyses demonstrate a six-fold increase in fishing intensity, and a 55% decline in finfish abundance during the period 1961-72. Plots of yield versus standardized fishing effort indicate that fishing mortality since 1968 has exceeded that which would result in sustaining a maximum yield from the stocks under equilibrium conditions. The projected maximum sustainable yield (MSY) from Schaefer yield curves is 900,000 tons2 , while the sum of the MSY's from individual assessment studies is 1,300,000 tons. It is suggested that because of species interactions summing the MSY's from individual assessments may be an overestimate of the total MSY.

Fishing with light

Abstract: Fishing with fire present light fisheries lighting fish and artificial light fishing lamps modern fishing methods and tactics species caught with light attraction.

Lighted fishing pole

Abstract: An elongated cylindrical handle constructed of transparent material, such as clear plastic, containing a flashlight-type mechanism for illuminating the handle which is attachable to a fishing pole so as to provide an illumination device integral with a fishing pole for use in changing tackle, baiting a fishing hook, enticing fish, or accessory lighting by a fisherman during dark periods of the day. The handle is detachable from the fishing pole to provide commpactness for storage or handling and so that the handle can be illuminated with the fishing pole attached or, on the other hand, the handle can be used as an ordinary flashlight with the fishing pole removed.

Exploited marine fishery resources of India: A synoptic survey with comments on potential resources

Abstract: Thc present stahls of the exploited marine fishery resources of India, based on avail- able data, is reviewed here. Details of the estimates of catch by mechanised and non-mechanis- ed boats as well as effort and catch per unit effort have been analymd year-wise (1962-1974) for the maritime States. Attention is ah drawn to some of our potential marine fishery re- sou-and to the new fishing grounds which have been investigated in the recent past. Tbere is an urgent need for planned exploration of new grounds; identification of -new resources; exploitation of wn-convtntiooal resources; diversification of fishing, particularfy fishing by mechanised crafts which arenow almost exclusively engaged in trawling for prawns; tbt intrduction of new and better techniques for capture fisheries; utilization of diverse resources; and the development of proper infrastructure facilities in the Marine Fishcries Sec- tor. The needs and possibilities are discussed here.

Creel Census of Amateur Line Fishermen in the Blackwood River Estuary, Western Australia, during 1974-75

Abstract: A creel census was carried out from May 1974 to April 1975 on the amateur line fishermen of Blackwood River estuary, from the Swan Lakes and Deadwater to Alexandra Bridge. The estimated total fishing pressure was 76 149 fisherman hours which was mainly concentrated in the summer and autumn months. The rate of success averaged 3.86 fish per fisherman per hour fishing. The estimated harvest of fish was 287 300. In the Hardy Inlet and Swan Lake region, western sand whiting (Sillago schomburgkii) was the main species caught for most of the year, except for the autumn months when Australian herring (Arripis georgianus) was the major species. In the Blackwood River, black bream (Mylio butcheri) dominated the catch throughout the year.

Extreme Risk of Mortality to Dugongs (Mammalia: Sirenia) from Netting Operations

Abstract: Successful and unsuccessful attempts at catching dugongs for research are described, including the capture of seven animals in one night near Townsville, Qld. Aspects of handling captured animals from a small boat and the effects of net fishing on dugongs are discussed.

The Giant Pacific Octopus

Abstract: Octopus dofleini is the largest of several octopus species inhabiting coastal waters from California northward to Alaska and across to Japan . It lives in caves and discarded man-made items from the intertidal zone to depths greater than 100 fathoms. Growth appears to be rapid, with individuals reaching weights greater than 100 pounds within about 5 years . Food for the creature includes crabs, clams, and fish. Adults commonly die after breeding activities. Information on its behavior has been increased through the use of scuba diving equipment. Divers routinely handle or capture large specimens without exceptional risk; however, several divers have been bitten . This naturally timid creature has sometimes attacked underwater swimmers, but usually incidents occur only after the animal is seized. There are limited commercial octopus fisheries for both halibut bait and human food. North American landings by all fishing methods are small .

Fish Bulletin 166. California Marine Fish Landings For 1974

Abstract: Landing bulletins provide basic catch records of amounts and values of various marine resources taken by California's commercial fisheries plus summarizations of catches of the partyboat sportfishing industry. Small quantities of freshwater fish taken commercially in inland areas also are detailed. These figures are of local, national, and international significance to fishery scientists and others interested in the wise utilization and management of California's living marine and freshwater resources. This report for 1974 is the 34th in a series stemming from the first gathering of commercial fisheries landing data by the California Department of Fish and Game in 1916 and the subsequent first publication of these catch data in 1929 for the years 1926 and 1927. California's fishery statistics are based on a system where fish dealers, processors, and operators of sportfishing partyboats send duplicate copies of their landing records to the department. Fish Bulletin 86, which reported the catch for 1950, describes fully the system and methods used in collecting commercial fish records. Basic principles remain the same today as then, although methods and equipment have been changed as necessary. The partyboat fishing system is described in Fish Bulletin 145 by Parke Young (1969).

Automatic fishing device

Abstract: An automatic fishing device, which includes a support, a fishing rod, a spring for holding the fishing rod in a predetermined first angular position relative to the support, and trigger apparatus for holding the fishing rod in a different position against the resilient force of the spring The trigger apparatus includes a trigger member having a notch and which is one end of the spring A stopper is slidably positioned on the fishing line so as to engage the notch when the fishing line is passed through the notch and so as to hold the fishing rod against resilient forces of the spring through tension in the fishing line

Roak fishing and its probable effects on the capture fishery of river yamuna in agra district

Abstract: The total annual yield of the economically important fishes of Yamuna in Agra is estimated from the catch statistics collected from 1960 to 1968. Monthly and annual fluctuations in catches, changes in fishing mortality, year-class strength, and mean lengths are presented and discussed in relation to the fishing methods, especially that of erecting barriers across the river, locally called 'Roak'. The catch by this method alone, constituting 54-88% of the total annual catch, is responsible for the declining trends in the major carp fishery of the area. Management measures that may be adopted to offer

Apparatus for use in long-line fishing

Abstract: The invention relates to an apparatus for use in long-line fishing, adapted to separately advance long-line snoods and fishing hooks, respectively, to a position in a blow device adapted to force the fishing hook necks individually into secured engagement with a head provided on each fishing line snood, possibly under simultaneous positioning of a bait on each fishing hook neck.

東北・北海道沖の南下サンマの資源動態について-iii

Abstract: 1) The dynamics of the saury population which occurs in the Pacific Ocean off northern Japan in autumn was studied by analysing the catch and effort statistics of the saury lift net fishery and length composition data of the catch. 2) Taking into consideration such population conditions as the different patterns of the dynamics among size categories, yearly change of body length, growth within the fishing season, and appearance and disappearance of the offshore fishing ground, the abundance index was calculated in terms of number by size category and fishing ground. 3) It was verified that the abundance index of the large sized fish in number by fishing ground was more steadily and rapidly decreasing than that of other size categories, but the tendency was quite variable by year. 4) Regression of the total coefficient of decrease of the available population on the effective overall fishing intensity was examined, but no positive correlation was found except in the large sized fish. The values of q and M were also estimated from the abundance index in number for every 10-day period, but unrealistic nagative values were often obtained for each size category. 5) Emigration and immigration of the fish shoals were considered to affect seriously the abundance index in number by size category and fishing ground, and the total coefficient of decrease; therefore, a new model on the dynamics incorporating the shift of fishing ground and oceanographic information must be developed in the future analysis.

An unusual portuguese fishing boat

Abstract: (1976). AN UNUSUAL PORTUGUESE FISHING BOAT. The Mariner's Mirror: Vol. 62, No. 1, pp. 15-21.

Fishing line sinker assembly

Abstract: A fishing line sinker assembly for deep sea fishing is provided which comprises a series of separate weights, some or all of which may be assembled together, or which may be used individually, so as to provide different weights for different fishing conditions.

A method of comparing the efficiencies of electric fishing operations

Abstract: A method is described whereby the efficiencies of two electric fishing machines may be compared by fishing a closed population on eight occasions at short intervals, the two fishing machines being used alternately. A practical example is given and the merits of the method are discussed.