Short-term and accurate prediction method of tuna longline fishing center and hooking route based on middle layer water temperature and ocean current spatial characteristics

Abstract

The application discloses a short-term accurate prediction method for tuna longline fishing center fishing ground and hooking route based on middle layer water temperature and ocean current spatial characteristics, and has the characteristics that the fishing ground position is accurately predicted according to the spatial vortex characteristics of the middle layer water temperature (reference 100m water layer, auxiliary reference 50m water layer) and the ocean current (preferably the ocean current of the 100m water layer, auxiliary reference the ocean current of the 50m water layer), and the hooking route is designed according to the method that the hooking route is maximally 90 degrees with the 100m water layer ocean current. The application can accurately predict the fishing ground position and the hooking route by combining the marine environment and the tuna longline fishing boat operation characteristics, and can improve the catch by 10-20% and improve the production effect.

Description

Technical Field

[0001] This invention relates to the field of data application technology for tuna longline fishing vessels, and in particular to a short-term, precise prediction method for tuna longline fishing grounds and casting routes based on mid-water temperature and ocean current spatial characteristics. Background Technology

[0002] Deep-sea tuna longline fishing holds a very important position in my country's high seas fishing industry. Due to its relatively complex operation, tuna longline fishing vessels, carrying fishing gear and bait, sail to suitable fishing grounds and cast their lines at a steady pace. The hooks float in the upper and middle layers of the ocean, drifting with the currents. The main catches are larger bluefin tuna, bigeye tuna, yellowfin tuna, and albacore tuna. Currently, fisheries often use surface water temperature and warm / cold eddies to guide fishing ground information, but this does not accurately reflect the environmental characteristics of tuna fishing grounds. Furthermore, there is still a lack of expertise in accurately determining the casting route and fish-finding methods for tuna longline fishing. Whether the problem lies in changes in the marine environment or a lack of fish at the fishing spot is a major headache for fishermen, often resulting in inconsistent catches. Short-term fishing ground forecasting remains a significant challenge in the fisheries industry. Tuna exhibit a high degree of migratory behavior, particularly their frequent daily vertical migrations from the surface to the mid-water layer and back again to feed and replenish body heat. Therefore, ocean currents significantly influence their habits. In fisheries, the characteristics of mid-water temperature and ocean currents are crucial for designing fishing routes and selecting fishing spots for tuna fishing; however, precise short-term forecasting methods for this purpose have not yet been reported.

[0003] In summary, there is a need to develop a new, precise method for predicting tuna longline fishing grounds and casting routes based on bottom water temperature and ocean current spatial characteristics, either in the short term or on the same day. Summary of the Invention

[0004] To overcome the shortcomings of existing technologies, this invention provides a precise prediction method for tuna longline fishing grounds and hooking routes based on bottom water temperature and ocean current spatial characteristics.

[0005] The technical solution adopted by this invention to solve its technical problem is:

[0006] A short-term, precise prediction method for the central fishing grounds and casting routes of tuna longline fishing based on the spatial characteristics of mid-layer water temperature and ocean currents. Under the premise of a safe marine environment for tuna longline fishing (i.e., waves less than 3m and wind speed less than force 6), the method accurately predicts the location of the fishing grounds based on a combination of spatial characteristics of mid-layer water temperature (reference 100m water layer, supplementary reference 50m water layer) and ocean currents (primarily the 100m water layer current, supplementary reference 50m water layer current). The method also designs the casting route by maximizing the angle between the casting route and the 100m water layer current to 90 degrees. The method includes the following steps:

[0007] (1) Summarize and generalize the subtle dynamic patterns of tuna longline fishing vessels and screen the influencing factors of fishing grounds, and identify the vortex locations in the 100-meter water layer (with a secondary reference at the 50-meter water layer) (see Figure 1 The higher water temperature zone at 100 meters (with 50 meters as a secondary reference) is an important reference indicator for tuna fishing grounds. At the same time, the hooking route should be at a 90-degree angle to the ocean current direction at 100 meters.

[0008] (2) Based on the ocean current visualization layer provided by the marine fisheries service platform, the tuna fishing grounds are initially determined around clockwise eddies in the Northern Hemisphere, followed by the areas around counterclockwise eddies; in the Southern Hemisphere, the tuna fishing grounds are initially determined around counterclockwise eddies, followed by the areas around clockwise eddies.

[0009] (3) Based on the area of ​​relatively high water temperature and relatively dense isolines around the vortex, the fishing ground range can be further narrowed down to about 30 nautical miles.

[0010] (4) Based on the various habits of tuna, the fishing route should be at a relatively large angle to the ocean current, preferably 90 degrees (see...). Figure 2 This hooking route and method is applicable to yellowfin tuna, albacore tuna, and bigeye tuna, etc.; the mid-level ocean current velocity is preferably 0.2 to 0.8 m / s (the ocean current arrows are mainly green and blue, with a few cases showing yellow ocean current arrows);

[0011] (5) It is recommended to use a straight line or a large arc when hooking (see...). Figure 2 All fishing hooks will be lowered at an angle of 90 degrees to the ocean current as much as possible.

[0012] As a preferred embodiment, if it is difficult to achieve a 90-degree angle with the ocean current at a depth of 100 meters in the descent route of step (1), it should at least be at a 90-degree angle with the ocean current direction at a depth of 50 meters.

[0013] As a preferred embodiment, the dense area of ​​bottom water temperature lines, the vortex direction of ocean currents and the ocean current velocity level in step (2) are mainly obtained in real time from the fishery deep-sea service platform; if there are no obvious vortices in the nearby sea area, the area where the ocean current turns can also be used as a reference.

[0014] As a preferred embodiment, steps (3) and (4) can be used to analyze the fishing grounds individually or in combination, depending on the actual situation.

[0015] As a preferred embodiment, the hooking route in step (5) forms a relatively large angle with the ocean current direction, preferably 90 degrees, which is mainly based on the analysis of the special living habits of tuna.

[0016] Beneficial effects: Compared with the prior art, the present invention has the following advantages and positive effects:

[0017] 1. The high spatial resolution visualization layers and data of sea state elements based on mid-water temperature and ocean current spatial characteristics play a role in finely depicting the environmental characteristics of fishing grounds, and can more accurately grasp the changing patterns and influencing factors of tuna fishing grounds.

[0018] 2. By carefully selecting predictive indicators for tuna fishing grounds, such as eddies and areas of high water temperature in the mid-water zone, fishery production output has been increased by 10-20%.

[0019] 3. This invention establishes a precise prediction method for tuna longline fishing grounds and casting routes based on mid-water temperature and ocean current spatial characteristics. This method can help companies increase the catch of fishing vessels by more than 20%. Attached Figure Description

[0020] Figure 1 This is a schematic diagram illustrating the precise location prediction of tuna longline fishing grounds.

[0021] Figure 2 This is a diagram illustrating the hook placement and method for tuna longline fishing. Detailed Implementation

[0022] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0023] Example 1:

[0024] like Figure 1 , Figure 2As shown, a short-term, precise prediction method for the central fishing grounds and casting routes of tuna longline fishing based on the spatial characteristics of mid-water temperature and ocean currents is proposed. Under the premise of a safe marine environment for tuna longline fishing (i.e., waves less than 3m and wind speed less than force 6), the method accurately predicts the location of the fishing grounds based on a combination of spatial characteristics of mid-water temperature (reference 100m water layer, supplementary reference 50m water layer) and ocean currents (primarily the 100m water layer current, supplementary reference 50m water layer current). The method also designs the casting route by maximizing the angle between the casting route and the 100m water layer current to 90 degrees. The method includes the following steps:

[0025] (1) Summarize and generalize the subtle dynamic patterns of tuna longline fishing vessels and screen the influencing factors of fishing grounds, and identify the vortex locations in the 100-meter water layer (with a secondary reference at the 50-meter water layer) (see Figure 1 The higher water temperature zone at 100 meters (with 50 meters as a secondary reference) is an important reference indicator for tuna fishing grounds. At the same time, the hooking route should be at a 90-degree angle to the ocean current direction at 100 meters.

[0026] (2) Based on the ocean current visualization layer provided by the marine fisheries service platform, the tuna fishing grounds are initially determined around clockwise eddies in the Northern Hemisphere, followed by the areas around counterclockwise eddies; in the Southern Hemisphere, the tuna fishing grounds are initially determined around counterclockwise eddies, followed by the areas around clockwise eddies.

[0027] (3) Based on the area of ​​relatively high water temperature and relatively dense isolines around the vortex, the fishing ground range can be further narrowed down to about 30 nautical miles.

[0028] (4) Based on the various habits of tuna, the fishing route should be at a relatively large angle to the ocean current, preferably 90 degrees (see...). Figure 2 This hooking route and method is applicable to yellowfin tuna, albacore tuna, and bigeye tuna, etc.; the mid-level ocean current velocity is preferably 0.2 to 0.8 m / s (the ocean current arrows are mainly green and blue, with a few cases showing yellow ocean current arrows);

[0029] (5) It is recommended to use a straight line or a large arc when hooking (see...). Figure 2 All fishing hooks will be lowered at an angle of 90 degrees to the ocean current as much as possible.

[0030] If it is difficult to achieve a 90-degree angle with the ocean current at a depth of 100 meters in the descent route of step (1), it should at least be at a 90-degree angle with the ocean current direction at a depth of 50 meters.

[0031] In step (2), the dense area of ​​bottom water temperature lines, the vortex direction of ocean currents, and the ocean current velocity level are mainly obtained in real time from the fishery deep-sea service platform; if there are no obvious vortices in the nearby sea area, the area where the ocean current turns can also be used as a reference.

[0032] Steps (3) and (4) can be used to analyze the fishing grounds individually or in combination, depending on the actual situation.

[0033] In step (5), the hooking route forms a relatively large angle with the ocean current direction, preferably 90 degrees, which is mainly based on the analysis of the special living habits of tuna.

[0034] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A short-term, precise prediction method for the central fishing grounds and casting routes of tuna longline fishing based on mid-water temperature and ocean current spatial characteristics, characterized in that... Under the premise of meeting the marine environment requirements for safe tuna longline fishing operations, the location of the fishing grounds is accurately predicted based on the spatial characteristics of mid-water temperature and ocean currents. The fishing route is designed based on the method of making the casting route at a 90-degree angle to the ocean current at a 100-meter water layer, including the following steps: (1) Summarize and summarize the fine change patterns of tuna longline fishing boats and screen the factors affecting the fishing grounds. The location of the vortex of the ocean current at 100 meters and the water temperature line at 100 meters are the reference indicators for tuna fishing. At the same time, the hooking route should be at a 90-degree angle to the direction of the ocean current at 100 meters. (2) Based on the ocean current visualization layer provided by the marine fisheries service platform, the tuna fishing grounds are initially determined around clockwise eddies in the Northern Hemisphere, followed by the areas around counterclockwise eddies; in the Southern Hemisphere, the tuna fishing grounds are initially determined around counterclockwise eddies, followed by the areas around clockwise eddies. (3) Further narrow the fishing ground area based on the area where the isolines around the vortex are relatively dense. At this time, the fishing ground area can be accurately reduced to 30 nautical miles. (4) Based on the living habits of various tuna, the angle between the hooking route and the ocean current direction is determined to be 90 degrees; this hooking route and method are applicable to yellowfin tuna, longfin tuna and bigeye tuna; the mid-level ocean current velocity is preferably 0.2 to 0.8 m / s; (5) The hook should be lowered in a straight line or a large arc, and the lowering path of all hooks should be at a 90-degree angle to the ocean current. If it is difficult to achieve a 90-degree angle with the ocean current at a depth of 100 meters in the lowering route of step (1), it should at least be at a 90-degree angle with the ocean current direction at a depth of 50 meters. The dense areas of bottom water temperature lines, the direction of ocean current eddies, and the speed of ocean currents are obtained in real time from the fishery deep-sea service platform; if there are no obvious eddies in the nearby sea area, the area where the ocean current turns can also be referenced. Steps (3) and (4) can be used to analyze the fishing grounds individually or in combination, depending on the actual situation. The angle between the hooking route and the ocean current direction in step (5) is 90 degrees, which is obtained based on the analysis of the tuna's living habits.

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