To Eat or Not To Eat Fish

Yellowfin tuna swim in a purse seine net in the central Pacific Ocean. © PAUL HILTON

Navigating the Complexities of Seafood Consumption

SEAFOOD HAS LONG BEEN AN INTEGRAL PART of the human diet, and some people consider it to be an inexhaustible food source. Fish-finding sonar, satellite locating systems, 100-mile-plus longlines with thousands of hooks, giant nets, fish aggregating devices (FADs), spotter helicopters, and factory ships operating around the clock, however, mean that many fish have nowhere to hide. 

Illegal fishing and destructive methods such as bottom-trawling and the use of cyanide and dynamite have left many species teetering on the brink of extinction and harm untargeted species. Each year fishers discard an estimated 38 million tons of bycatch — juvenile fish and unwanted species. These marine animals are often dead when crews throw them overboard to free up freezer space for higher-value specimens. 

Overfishing has caused dramatic decreases in global stocks of various types of tuna, salmon, cod, sharks, and turtles, among others. The World Wildlife Fund notes reports that the global fishing fleet is 2.5 times larger than what the oceans’ fish stocks can support. The WorldFish Center, a nonprofit nongovernmental research organization, reports that average global fish consumption has almost doubled in less than 50 years, and catches would have to double again in the next 25 years to keep up with growing demand. 

As a conservation photojournalist, I’ve seen the best and worst of the fisheries industry. I’ve thought long and hard about seafood consumption and the opportunities some of us in certain parts of the world have to reduce our seafood consumption. But it’s a different story for people in some Pacific islands and other developing nations, where fish might be the only readily available protein source.

Purse Seine Fisheries

Purse seiners target whole schools of fish and leave nothing behind. Industrial fishing fleets use sonar and helicopters to track fish across large expanses of the ocean. The fishers use a vertical curtain net 1.25 miles (2.4 kilometers) wide and 200 feet (61 meters) deep to surround the school. The bottom of the net encloses the fish when drawn together, and the crew winches the whole mass aboard. Fish don’t have a chance against this industrial fishing method. 

The target species might be tuna, but the bycatch includes juvenile tuna, other fish species, sharks, sea turtles, and marine mammals such as dolphins and whales. The sustainability of purse seine fisheries depends on various factors, including the abundance of target species and the implementation of effective management practices. Proper management is crucial to prevent overfishing, mitigate bycatch, and ensure the long-term viability of fish stocks. 

Yellowfin tuna swim in a purse seine net in the central Pacific Ocean. © PAUL HILTON

Longline Fisheries 

The longlines fishers use in tropical waters have a main line about 1 mile (1.6 kilometers) long with smaller branch lines attached at intervals. Branch lines have baited hooks made of stainless steel or other durable materials. Depending on the fishing operation, the lines can have a few dozen to several thousand hooks, and most boats have two or three out at a time. 

The main line is typically horizontal in the water column, either near the surface or closer to the seabed. Floats attached to the main line keep it buoyant, and weights or anchors keep it taut and in position. 

Longline fisheries target species that are attracted to bait, such as large predatory fish. The bait varies depending on the target species and fishing location. Common bait includes fish, squid, or other natural prey. The longline stays in the water for a few hours to several days, depending on various factors, including fishing regulations and the target species’ behavior. Reeling in the main line brings the hooked fish to the surface. 

Most of these boats call themselves tuna boats, but many target sharks. The crew is usually overworked and underpaid and can be at sea for months on end. Like purse seine fisheries, longline fishing can result in bycatch, including sharks, sea turtles, seabirds, and other species that can inadvertently get caught on the hooks.

Mahi-mahi (dolphinfish) are stacked into a shipping container at Dong Gang fishing port outside Koahsiung, Taiwan. © PAUL HILTON
A commercial fishing boat catches tuna in a purse seine net in the central Pacific Ocean. © PAUL HILTON

Line Catching 

While “line-caught” can refer to several methods that don’t use a net, I use the term to differentiate a single line and hook from the longline setup. Many people consider this method more sustainable and environmentally friendly than other industrial fishing techniques. Since line fishing involves a more selective process, it reduces the risk of inadvertently catching other marine species, especially endangered or threatened ones. 

Compared with trawling, which involves dragging nets along the ocean floor, line fishing causes less damage to the seabed and marine habitats. It helps preserve the ecosystem and maintain the marine environment’s overall health. Line-caught fish are handled more carefully, resulting in less stress and better quality, which is particularly important for sushi-grade tuna or high-end products. It is generally more expensive due to the method’s labor-intensive nature. 

Line fishing is a slower process than more industrialized methods, which can lead to lower catch volumes. This difference can make it challenging to meet the high market demand, potentially driving up prices. The method is more commonly associated with artisanal or small-scale fishing practices. 

It’s important to note that the specific pros and cons of line-caught fish may vary depending on the fishing practices, regulations, and individual circumstances. Nonetheless, line fishing generally offers several sustainability and product quality benefits.

Sadly, I have sometimes seen dynamite fishing alongside tuna line-catching. Fishers throw dynamite into a pod of dolphins that they know are tracking schools of yellowfin tuna. Many dolphins die, and the tuna float to the surface. Then fishers move in and collect the tuna, which is packaged and sold as sustainably caught. This practice is highly illegal but still happens in remote areas. 

Pole and line fishing is more targeted and sustainable than longline or purse seine fisheries. This image is from Bitung, Sulawesi, Indonesia. © PAUL HILTON

Pole and Line Fishing

“One fisher, one fish” is a sustainable practice emphasizing responsible fishing and conservation. Pole and line fishing enables fishers to choose the specific species they want to catch. Adhering to size limits specified in local fishing regulations helps ensure that fishers catch only mature fish and that the population can sustain itself. In my mind, this is the only truly sustainable fishing practice. 

Barbless hooks make it easier to release fish that don’t meet the regulations, reducing injury and stress to the fish. Avoiding live bait or using sustainably sourced bait helps prevent damage to marine habitats. Adhering to fishing seasons and avoiding protected or restricted areas, such as marine reserves, ensures that fish populations have time and space to reproduce and thrive. By following these practices, individuals can contribute to sustainable fishing and help preserve fish populations for future generations.

Should We Eat Fish?

The question of whether to eat fish is a complex issue. Given the state of the world’s fish populations, it’s best to avoid seafood whenever possible. Yet, fish are a rich source of high-quality protein, omega-3 fatty acids, vitamins, and minerals. These nutrients are associated with numerous health benefits, including heart health, brain function, and reducing the risk of certain diseases. 

Consuming fish has several upsides, but there are also concerns beyond sustainability. We should be aware of potential health risks from mercury contamination, microplastics, and other pollutants in many fish species. 

Eating fish is a personal decision based on numerous factors. In many places around the world, it’s not even a viable choice to remove fish from your diet. Balancing the nutritional benefits of fish with concerns about sustainability, health risks, and ethical considerations can be challenging. 

By staying informed about fishing practices, choosing sustainably sourced seafood, and exploring alternative protein sources if possible, we can make conscious decisions that align with our values and contribute to a healthier planet. Ultimately, finding a balance that promotes personal well-being and the long-term health of our oceans is crucial. AD

© Alert Diver — Q3 2023