Fishing Survey

Fishing Survey

 

a series of activities that include searching for, observing, and assessing the commercial value of aggregations of marine organisms (fish, mollusks, crustaceans).

Fishing survey is usually broken down into search operations and the survey proper. The search includes preliminary determination of the distribution of the target organisms, identification of regions favorable for the formation of aggregations, and the actual search for the aggregations. The survey involves determining the size and value of the aggregations, making short-term forecasts of the stability and movement of the aggregations, and guiding the fishing fleet to the marine animals.

Fishing survey involves both exploratory and operational work. The first includes the search for new fishing regions and commercial targets. The formation of commercial aggregations and their paths of migration are studied, as is the behavior of marine organisms in different periods of the year. Aggregations

Table 1. Fineness of metals and alloys in the USSR
Metric systemZolotnik systemCarat systemAlloy colorHardenerBasic use
1 Large quantities used during the Great Patriotic War (1941-45)2 Most widely used alloy in USSR3 Most widely used alloy in Western Europe 4 Of no practical significance in the USSR 5 Range of 10 fine
    Gold alloys 
9589223YellowCopperWedding rings
7507218RedCopper, silverJewelry
   YellowFishing SurveyFiligree work
   Yellow
   WhiteFishing SurveyDiamond jewelry
   White
5835614RedFishing SurveyJewelry
   Yellow
   GreenSilver, copperIndividual parts injewelry
500Red1Copper, silverJewelry
   Pale yellow1SilverFiligree work
375Red1Copper, silverJewelry and watchcases
   PinkSilver, palladium, copperWedding rings
    Silver alloys 
960WhiteCopperDelicate filigree work
925WhiteCopperTableware
9168822WhiteCopperFiligree work, enameled articles
8758421White2CopperJewelry and domestic items
800White3CopperJewelry and domestic items
750White with slight yellowish lintCopperJewelry, fashion accessories
    Platinum alloys 
950WhiteCopperDiamond jewelry
    Palladium alloys 
850WhiteSilver, nickelWedding rings, in combination with gold 583 fine
500White4Silver, nickelJewelry
    Gold leaf 
1,000YellowFishing SurveyGilding of bas-reliefs on buildings, monuments, church domes
990-91 O5Yellow
750Green
    Silver leaf 
1,000WhiteFishing SurveySilvering of bas-reliefs on buildings, monuments, church domes
990-9105White

are evaluated, and the economic viability of exploiting them is determined. Operational work involves guiding fishing vessels to schools of fish, making recommendations concerning the deployment of the fleet, and observing hydometeorological and other working conditions.

Fishing survey employs direct and indirect methods. Among the direct methods are sample fish catches and the use of such detecting devices as sonar fish-finders. Indirect methods include the determination of the position of aggregations on the basis of environmental conditions. The indirect approach is the primary one, with direct survey used mainly to confirm results obtained indirectly. Fishing survey is based on the study of those environmental factors (for example, water temperature) that determine the range of fish distribution. It also takes into account seasonal physiological changes undergone by the animals.

Fishing survey employs the experiences of many sciences, including ichthyology, oceanography, hydrochemistry, and hydroacoustics. It is conducted through the use of fish-finding equipment mounted on ships, airplanes, and helicopters. In the USSR, specialized organizations of the fishing industry are involved in fishing survey.

V. M. LIFSHITS

References in periodicals archive ?
The report of the first fishing survey of the lake of 1927/1928 [1] and subsequent reviews (such as EAFFRO, 1954 - 1960) [5] all emphasized the dangers of over-fishing tilapia stocks.
A report on the fishing survey of Lake Victoria 1927-1928, and appendices.
Building on the 2010 recreational fishing survey, this new survey will collect more regionally focused information on where and how people fish, what they catch and the type of fishing experiences they want, Mr McVeigh said.
Exploratory fishing survey of the inshore fisheries of Guam.
Project officer Steve Hudson said: "The mission was to enable fish free access to all habitats in the river to boost fish populations whilst also monitoring improvements through electro fishing surveys carried out by Durham University.
The elusive nature of white sharks and the lack of historical data about their population levels required the authors to rely on sightings of sharks, as opposed to other ways to count sea life, such as commercial fishing surveys and census counts, Curtis said.
This belief was formed on the basis of results from submersible and fishing surveys that found some species in the water column adjacent to areas of high relief, such as underwater headlands, ledges, outcrops, and pinnacles (Ralston et al.
Common shallow-water sampling techniques, such as diver transects, however, are not logistically feasible at depths below 100 m, and fishing surveys can be destructive to local populations.
This parameter also has been found to be highly correlated with the traditional parameter of CPUE used in fishing surveys (Ellis and DeMartini, 1995).
uk The Wear Rivers Trust were busy over the autumn in assessing the population of the river and have now completed over 25 electro fishing surveys using volunteers from local angling clubs.
Fishing pressure, both recreational and commercial, affected rockfish survival and species composition long before the recreational fishing surveys used in this study were conducted, making it impossible to define the pre-exploitation species composition.
Fish will be stunned this summer during a series of electric fishing surveys to assess the state of local fish populations in the North-East.