In the vast expanse of the world’s oceans, tuna fishing is a highly lucrative and complex industry. With the demand for this popular fish constantly on the rise, commercial tuna fishing has evolved into a precise and sophisticated process. From scouting the open waters to capturing the fish with precision, this article serves as a comprehensive guide to understanding how the tuna fishing industry successfully catches this prized species on a large scale. Whether it be the deployment of sophisticated gear or the involvement of skilled professionals, each step plays a crucial role in ensuring the sustainable exploitation of tuna.
Preparing The Fishing Gear: The Essential Equipment For Tuna Fishing
Tuna fishing is a complex process that begins with preparing the fishing gear. The success of the catch largely depends on having the right equipment. Commercial tuna fishing vessels are equipped with a variety of essential tools needed to catch these fast and powerful fish.
One of the most important pieces of equipment is the fishing net. These nets are specially designed to withstand the force of the tuna and are often made of strong and durable materials, such as nylon or polyethylene. Additionally, the nets are equipped with floats and lead weights to ensure they stay submerged at the desired depth to intercept the tuna schools.
Other essential gear includes fishing lines, hooks, and baits. Longline systems are commonly used, consisting of a main line with numerous baited hooks that can reach several miles in length. These lines are equipped with buoys to mark their location and prevent entanglement with passing vessels.
Furthermore, specialized equipment such as radar systems and sonar devices are utilized to locate and track tuna schools. These technologies help fishermen identify the optimal areas for setting their nets or deploying the longline.
Overall, thorough preparation of the fishing gear ensures that commercial tuna fishing operations are efficient and effective in capturing the desired tuna species.
Locating The Tuna: Tracking Techniques And Technologies
Commercial tuna fishing heavily relies on effective tracking techniques and advanced technologies to locate tuna schools. Tuna are highly dynamic and migratory fish, making their precise location a challenging task. However, with the aid of modern tools, fishermen can increase their chances of success.
One commonly used tracking technique is the use of sonar technology. Fishermen utilize echosounders to emit sound waves into the water, which bounce back when they encounter objects like tuna or other fish. By analyzing the returned signals, fishermen can determine the presence of tuna and estimate the size and depth of the school.
Another tracking method involves the use of fishing buoys equipped with satellite tracking systems. These buoys are designed to be easily deployed and float on the water’s surface. They transmit location data in real-time, allowing fishermen to follow the movements of tuna schools. By analyzing the information received, fishermen can adapt their fishing strategies to target the densely populated areas.
In recent years, advancements in satellite technology have further revolutionized tuna tracking. Satellite imagery, such as thermal imaging, allows fishermen to detect temperature variations in the water that indicate the location of tuna schools. This information helps fishermen identify productive areas where the likelihood of catching tuna is high.
By employing a combination of tracking techniques and technologies, commercial fishermen can increase their efficiency in locating tuna schools, ultimately leading to a more successful and sustainable fishing operation.
Setting The Nets: Deploying The Tools To Catch Tuna
Setting the nets is a crucial step in the commercial tuna fishing process. It involves deploying the tools required to effectively catch the tuna schools.
Commercial tuna fishing vessels are equipped with large, specialized nets known as purse seines or driftnets. These nets are typically made of strong nylon material and can stretch for hundreds of meters. Before setting the nets, the crew meticulously checks them for any damages or weaknesses that could compromise their effectiveness.
Once the fishing grounds have been identified, the vessel positions itself strategically around the tuna schools. The crew then carefully lowers the nets into the water, ensuring they form an extensive loop around the targeted area. Floaters and weights are attached to the top and bottom of the net to keep it afloat and prevent fish from escaping underneath.
To maximize the catch, some vessels also use fish aggregating devices (FADs) in conjunction with the nets. FADs are floating objects such as buoys or drifting debris that attract tuna, creating a concentration in a specific area. By strategically placing the nets around FADs, fishermen increase their chances of successfully capturing a significant quantity of tuna.
This method of deploying nets is effective because it allows fishermen to encircle and surround large schools of tuna, making it easier to haul them in later. Properly setting the nets is crucial for ensuring a successful catch and minimizing any potential harm to the environment.
The Purse Seine Method: Surrounding And Encircling The Tuna Schools
The purse seine method is a commonly used technique for catching tuna commercially. This method involves surrounding and encircling the tuna schools using a large net, known as a purse seine net.
To begin, a spotter plane or a fishing vessel equipped with fish finders and sonar devices is used to locate the tuna schools. Once the schools are spotted, the fishing vessel maneuvers into position, and the crew deploys the purse seine net around the school by encircling it.
The purse seine net is a large, cylindrical net that can extend up to several hundred meters in length. It is equipped with floats on the top to keep it afloat and weights on the bottom to submerge it partially. The net also has a drawstring running through its lower edge, allowing it to be closed off like a purse once the tuna are encircled.
Once the purse seine net completely encircles the tuna school, the drawstring is pulled, closing the bottom of the net. This prevents the tuna from escaping. The net is then slowly hauled back onto the fishing vessel using a mechanical block and tackle system or hydraulic winches.
This method allows for the capture of a large number of tuna in a single operation. However, it is essential to ensure that the tuna caught are of the desired size and species, as well as adhering to sustainability practices to protect the long-term viability of tuna stocks.
The Longline Technique: Baiting And Hooking Tuna On A Massive Scale
The longline technique is a popular method used to catch tuna on a massive scale. It involves setting a fishing line that can stretch for several miles, equipped with thousands of baited hooks. This method is highly effective in targeting pelagic fish like tuna.
To begin, the fishing vessel deploys the longline by releasing it into the water. The mainline, which is typically made of strong monofilament, is carefully spooled out while attached to buoys that keep it afloat. Branch lines, also known as snoods, are attached to the mainline at regular intervals, dangling with baited hooks.
These hooks are carefully set with different types of bait to entice the tuna. The most common bait used is squid; however, other options like fish, crustaceans, or even artificial lures can also be used depending on various factors, such as the target species and the fishing location.
Once the longline is fully deployed, it is left in the water for a specified time, usually ranging from a few hours to a day. During this waiting period, tuna are attracted to the baited hooks and are hooked once they take the bait.
After the allotted time has passed, the crew begins the process of hauling in the catch. This involves reeling in the longline while carefully removing any caught fish from the hooks. The tuna are then either put directly into ice storage on the vessel or transferred to smaller holding tanks for sorting and processing later on.
The longline technique is not only efficient but also allows fishermen to target specific species, resulting in higher-quality catches. However, it is important for commercial tuna fishing operations to be mindful of sustainability practices and minimize bycatch to protect the overall marine ecosystem.
Hauling In The Catch: Retrieving And Securing The Tuna From The Nets
After successfully setting the nets and encircling the tuna schools, the next crucial step in commercial tuna fishing is hauling in the catch. This task requires precision, coordination, and expertise to ensure that the captured tuna are retrieved safely and efficiently.
Once the tuna are surrounded by the nets, the crew members onboard the fishing vessel use winches to gradually pull the net closed, reducing the available space for the fish to swim. As the net gets smaller, the fish become concentrated, making it easier to haul them aboard.
To retrieve the catches, specially designed nets known as purse seines are used. These nets have a drawstring at the bottom, allowing the crew to close the net tightly once the fish are trapped inside, preventing any escape. The purse seine is then carefully brought onboard, ensuring the net does not tear or release any fish during the process.
Once on deck, the crew swiftly removes the trapped tuna from the net, placing them directly into brine-filled containers to maintain freshness. This speedy transfer minimizes damage to the fish and helps preserve their quality. The containers are then sealed, and the haul is ready for further processing and storage.
Processing And Storage: Ensuring Quality And Safety Of Commercially Caught Tuna
After the tuna have been successfully caught, the next crucial step is to process and store them properly to maintain their quality and ensure consumer safety. Processing the tuna involves several steps that need to be executed efficiently.
The first task is to clean the fish thoroughly, removing all impurities such as scales, innards, and blood. This is followed by the removal of the fish’s head and tail to prepare it for further processing.
Once cleaned, the tuna is typically cut into different portions, depending on market demand. These portions are then graded based on their size, quality, and fat content. This grading process ensures that the tuna is sorted into appropriate categories for pricing and distribution.
Following the grading process, the tuna is either flash-frozen or chilled depending on the desired final product. Flash-freezing preserves the fish’s freshness and quality by rapidly lowering its temperature, while chilling involves a slow cooling process. The choice of freezing method depends on the fishing vessel’s facilities and the preferences of buyers.
After freezing or chilling, the tuna is packed into suitable containers, such as vacuum-sealed bags or styrofoam boxes, to maintain its freshness during transportation. These containers are then stored in a cold storage facility, where the temperature is carefully controlled to prevent any bacterial growth and maintain optimal quality.
By following strict processing and storage protocols, commercial tuna fisheries ensure that their catch reaches consumers in the best possible condition, preserving the taste, texture, and nutritional value of this prized seafood.
Frequently Asked Questions
1. How is tuna caught commercially?
Commercial tuna fishing involves the use of fishing vessels that employ various methods such as purse seining, longlining, and pole-and-line fishing. These methods target tuna schools and capture large quantities of tuna for commercial purposes.
2. What is purse seining and how is it used to catch tuna?
Purse seining is a common method used in commercial tuna fishing. It involves encircling a school of tuna with a large net called a purse seine, which is then closed at the bottom to trap the fish. The net is then drawn in, bringing the captured tuna to the surface and allowing them to be easily caught.
3. How does longlining contribute to commercial tuna fishing?
Longlining is another method employed in commercial tuna fishing. It involves setting long lines with multiple baited hooks at various depths in the water, targeting tuna and other species. The lines can stretch for miles and are left in the water for a certain period of time before being retrieved, with the captured tuna removed from the hooks.
4. What is pole-and-line fishing and its significance in commercial tuna fishing?
Pole-and-line fishing is a traditional method used to catch tuna commercially, particularly for the canning industry. It involves using a fishing pole with a single line and baited hook to target individual tuna swimming near the surface. This method is often practiced with the help of bait fish or by attracting tuna with the sound of feeding birds. Pole-and-line fishing is considered more selective and sustainable compared to other methods.
The Conclusion
In conclusion, the commercial tuna fishing process involves a combination of traditional and modern techniques to ensure a successful catch. From the use of radar to locate tuna schools, to the deployment of purse seine nets and the careful handling of the fish, commercial tuna fishing is a complex and precise operation. This guide has provided insight into the various steps involved in catching tuna commercially, shedding light on the challenges and considerations that fishermen face in their quest to supply this highly sought-after seafood to consumers worldwide.