Long-Term Effects of Overfishing
Due to an increase in the efficiency of commercial fishing, a growing global population, as well as a rapid increase in globalization of the fishing industry over the last few decades, more and more people are competing for fewer and fewer fish in the ocean.
Sadly, our oceans are in trouble today, with an estimated 85% of global fish stocks that are stressed, in decline, or have already collapsed. The journal Science has predicted that if current trends continue, the world will likely run out of seafood by the year 2048 due to overfishing, pollution, and other environmental issues2. Such a gloomy projection simply need not be if humanity takes decisive action right now to manage global fish stocks sustainably for future generations.
In this article, we will discuss many of the long-term effects of overfishing, and what some people are doing to try to solve this problem.
Long-term effects of overfishing
Loss of livelihoods for fishermen, forcing them to work in other professions in other places. The global poor will likely suffer the most from food scarcity issues, malnutrition, and economic insecurity due to the disappearance of global fish stocks.
Reduction in the social, health, and economic wellbeing of coastal communities due significant losses of fish stock populations that provided income and an important food source. Such situations are likely to increase higher in coastal areas and poverty.
Negative impacts on the health of the world’s oceans. When fish species are overfished, they will impact their marine habitat and the populations of other species because the ecosystem has been pushed out of balance.
Negative impacts on multiple levels of marine food webs. For instance, with overfishing of prey species like sardines and anchovies, there may be no more food left for predators to eat, and overfishing predator species like salmon and tuna may lead to an overpopulation of prey species, that then might experience a population crash because they exhaust their own food supplies.
Changes in species dynamics, such as with predator-prey relationships. Changes in fish population levels can cause shifts in what certain species use as food sources. With a scarcity of their typical food sources, some species may not be able to adapt to the new conditions and might die out. Other species, such as whales and dolphins, are likely to become more rare as their food sources are reduced.
Reduction in overall marine biodiversity.
Ecosystem shifts, resource depletion, reduced biological growth rates, and low biomass levels.
Already-stressed ecosystems may become more vulnerable to invasive marine species that can cause damage.
Some solutions to overfishing
Since billions of people around the world depend heavily on seafood everyday as a critical source of protein, it is important that we tackle this problem with full-force. When managed properly, many fish populations should rebound if given the opportunity.
Many government and international bodies are currently working to implement policies that reduce overfishing activities.
- Implementation of quotas and limits on total catch and species, such as quotas on the number of days at sea, limits on the number of vessels in a given area, and seasonal restrictions.
- Enforcement of quotas and regulations that are already in place. In some cases, quotas and regulations are not properly enforced, making them ineffective by themselves at protecting fish populations.
- Establishment of marine protected areas.
- Use of Aquaculture. Aquaculture, the captive raising of fish, can provide a more sustainable alternative to wild caught fish. There can be negative impacts on wild fish populations, however, such as water pollution. Also, farming predatory fish like salmon can require fish feed that is made from parts of wild fish.
- Recreational fishing can implement catch and release policies to reduce negative impacts on population levels of fish.
- Charge the fishing industry to no longer prioritize commercial fishing interests over other interests, such as marine ecosystem health and poverty.
- Reduce government subsidies to the fishing industry, which do not allow for the true socio-economic and ecological costs of overfishing to be demonstrated.
- Efforts to reduce the exploitation of marine mammals and other non-target marine life via bycatch.
- Multi-species management is being used to conserve ecosystems and to increase biodiversity.
- Protection of ecosystems, especially vulnerable ones.
Establishment of marine reserves where no commercial fishing is permitted.
- Involve local communities to determine place-based, sustainable solutions that do not deplete fish stock and help to provide a good living to local communities.
For information on how overfishing impacts coral reef marine systems and to learn about the efforts that are being implemented to solve that challenge, check our article on The Effects of Overfishing on Coral Reefs.