Biological Attrition, Decline and Future Issues as a Result of Fish Oil Harvest and Production withi

*Originally written as an assignment for a biology course. Most of these are hypotheses I tried to synthesize. Many are unsubstantiated as combined information.

Biological Attrition, Decline and Future Issues as a Result of Fish Oil Harvest and Production within Contemporary Societies

Abstract

Despite recent declines in demand, the commercialization and production of fish oil continues to be a common factor across the globe. Fueled by particular research which suggests health benefits of consuming fish oil, purchasing of such commodity is still colloquial within contemporary societies. However, the capturing, rearing, production and transport processes for fish oil create direct and indirect consequences for global biological ecosystems. This includes but is not limited to decrease of fish species and stocks, drainage of inland water sources, declines of wildlife within local areas, along with indirect environmental fragmentation, pollution and increased greenhouse gas output across the biosphere. Suggestions on mitigating damage through proper farming management, fish stock harvest restrictions and bioengineering for fish oil and the like may allow for preservation and conservation of biological diversity for future generations.

Introduction

With the ever increasing problem of obesity, heart disease and bodily issues, many individuals have begun switching to alternative methods of healthy daily sustenance intake. One such switch is the general push to supplementation of the human diet. Such action includes the addition of daily or weekly consuming of various vitamins, supplements and medicines to, but are not limited to, boost metabolism, decrease disease rate and/or increase vitamin content. However, while some research expressed positive correlation to health via supplement intake, some suggest otherwise (Guallar et al., 2013). Despite the conflicting sources, a significant proportion of individuals still purchase and use such supplements. Thus, the global demand for such supplements caused a large, commercialized consumer market for these commodities. However, the increased pressure and demand for such products unfortunately often have negative feedback on the environment, the biological processes and general ecosystem health.

One such product is fish oil or oil derived from tissues of various fish species. Commercialized versions in Western and Eastern societies often consist of oils within a softgel capsule, similar to the form of many cold and flu symptom medications. These oils often contain chemicals such as omega-3 fatty acids, along with docosahexaenoic acid, the latter of which is a precursor chemical which reduces inflammation (Moghadasian, 2008). Marketers thus utilize such properties to sell products to the general public. While fish oil in itself has been utilized by many groups within history, most notably the Inuit People, commercialized versions today are purchased and used worldwide by much of modern societies. Fish oil is often extracted from fish species which have strict and limited netting seasons. However, due to such high demand and commercialization, fish oils within much of the world are now a year-round item found within the shelves of pharmacies or any supermarket chain’s supplements section. The production itself, however, is often limited to large factories with machinery which could physically and efficiently separate oil from other components, such as water, proteins and other minerals within the fish tissues.

Background

In its basis, fish oil is contained within many species of commercial fish. This includes: herring, sardine, salmon, halibut, tuna and shark. However, it is important to also realize that source fish for fish oil do not themselves produce omega-3 fatty acids. Instead, such fish accumulate fatty acids through consumption of other fish (Venturi et al., 2004).

Various methods of extraction have been developed over the years to efficiently separate the fish oil itself from other unwanted particles. One such method, and arguably most common, is heating and then pressing or centrifugation. Within this process, fish are heated up to 95 °C to allow for separation of water and oil from tissue protein. This supernatant of materials is then “pressed” to squeeze away the liquid from the solids. Alternatively, and sometimes in conjunction with pressing, the materials are centrifuged to separate the oils from the other liquids. The crude fish oil is then stored in steel tanks. Additional processes, such as winterization (cooling and crystallization), neutralization (removal of fish oil acids), refinement/purification (bleaching and filtration) and deodorization may also be applied. The application of all such processes creates ultra-refined fish oil, which contains 84% omega-3 fatty acids and docosahexaenoic acid (FAO). It is these ultra-refined oils which are then machine packaged into capsule gels and then into plastic stock bottles which are then shipped and sold to various commercial markets across the globe. Within a large number of contemporary societies, such shipping involves the use of automobiles and trains.

While a significant amount of fish oil is now harvested from species grown within aquaculture, a large number are still derived from wild-caught sources. Increases in technological methods of oil extraction, along with commercial raising of predatory fish species which contain high amounts of omeg-3, both contribute to modern day fish oil production. Thus, the demand for fish oil has slightly decreased within the past decade (Bostock et al., 2010). However, despite increase in aquaculture, traditional or commercial harvesting of fish, such as herring (Clupea sp.) continue both as a source of meat and as a source of oil (harvesting from commercial fishing fleets). In addition, increased levels of fish aquaculture has created an increased conversion of land for commercialization, as well as an increased demand for fish meal and other products to sustain production. Ultimately, despite a slightly decreased demand for fish oil, the still significant demand created and continues to create ecological and biological problems for Earth’s natural resources. A combination of direct fishing methods, along with indirect methods of extraction, aquaculture and commercialization, all test the limits of global environments, biomes and ecosystems.

Environmental Impacts

Direct Impacts

With a large number of cases of commercialization of products, fish oil production too, has a significant direct impact on the biological diversity and processes across the planet. Arguably, the most significant ecosystem directly affected by fish oil production are the oceanic waters. Increased fish harvest in certain areas have created significant declines in the diversity and size of individuals, most notably the larger, predatory species. Commercialized fishing within the Pacific during the 1950’s to the 1990’s have created a decline of 21% within shark and tuna. Additionally, individual fish surviving within the remaining population expressed a drastic decline in average size as a result of overharvesting. Pacific blue sharks (Prionace glauca) averaged 57.7% less in mass in the 1990’s when compared to the 1950’s (Ward & Myers 2005). However, such threat extends well beyond just top predators.

Individual species aside, general marine fisheries themselves are also suffering from commercial harvesting for oil and meat. While only about 13.5% of Red Listed marine fisheries are considered threatened, 40% of those fisheries, along with 21% of all populations with stock assessments, are currently below their normal reference points (Davies & Baum 2012). While generalized assessment of exploited marine species may be overall controversial due to variations in scientific uncertainty (along with economic and political reasons), research results suggest that decline rate criteria are consistent with population viability and visible analyses. In fact, nearly a quarter of all the fish populations within 76 stocks evaluated by researchers met one or more of the threat criteria (two criteria on decline rate one on population viability) and none produced false alarms. Therefore, while controversy continues, it appears such assessment is indeed significant and that there most certainly is correlation between threat factors, commercialized harvest and decline of marine stocks (Dulvy et al., 2005).

In combination to declines within individual fish species and general fish stocks, other organisms aside from predaceous fish also declined, including previously common species. Fish-eating birds, which are easier to count than the fish themselves (Tasker et al., 2000), often fluctuate with the rise and fall of nearby fish stocks. Therefore, they are often a good gauge to local oceanic fish stock health for their populations. Between 1966 and 2010, herring gulls (Larus argentatus), a bird found across the Atlantic Coasts of North America and Europe, expressed a 78% decline as a result of commercial fish exploitation, as well as changes to commercial fishing methods (targeting many fish species rather than just one or two). In correlation, decreased aquatic prey availability often forces species such as the herring gull to change survival methods and feed more upon terrestrial prey rather than aquatic prey, which has mixed results for it has been shown that terrestrial prey has decreased nutrition (Herbert et al., 2008).

However, while oceanic locations are threatened by commercial harvest of fish for oil, shifts within other processes for fish oil production are also significant in changing the ecology of various ecosystems. Global farmed fish (and shellfish) has more than doubled within the past 15 years (Naylor et al., 2000). Theoretically, increased aquaculture may have decreased, to an extent, demand for wild-caught fish. However, it increased other demands, such as elevated levels of water drainage to support fish farms, which severely alters ecological habitats. Likewise, demand for aquaculture of carnivorous fish species for oils and food, such as salmon, requires large inputs of wild fish for feed often in the form of fish meal and other by products from fish oil production (Bostock et al. 2010), which partially or even completely, negates decreasing the demand on wild fish stocks. Additionally, some farming systems also reduce wild fish supplies through habitat modification (draining of a lake or wetland). Finally, initiation of a farm stock itself may also require collection of wild seedstock and thus cause the depletion of certain wild habitats of available fish (Naylor et al., 2000).

Consequently, because aquaculture itself may further decrease limited ecological resources, other species may also suffer from such changes. Draining of waterways decrease available water, which is even more significant during dryer periods. Amphibians, insects and many other water-based organisms may decline as a result of over-irrigation for aquaculture. Similarly, other organisms such as plants, birds and mammals species which are dependent on lakes, streams or prairie marshes may also decline as a result of aquaculture drainage. Species which prefer to nest in inland marshes, such as the Franklin’s gull (Leucophaeus pipixcan), suffer dramatic declines and nesting failures due to increased drainage of their wetland ecosystems (Knopf, 1994). As a result of the demand both in agriculture but also aquaculture, organisms like the Franklin’s gull have declined by over 88% (Burger & Gochfeld 1994). Ultimately, fish oil harvests have generated a multitude of direct impacts on the global ecology of the planet. However, such harvest impacts resonate beyond immediate, local and direct problems.

Franklin's Gull

Wetland

Indirect Impacts

Aside from the more direct impacts of fish stock depletion and aquaculture’s water dependence, other more indirect results from the demand for harvesting of fish oils also play a significant role in changing the ecosystems. One particular problem is the issue of by-catch, or capturing an organism which was not an intended target for the excursion. A common example is the capture of predatory species like octopus and shark within nets built for species such as cod. Additionally, commercial fishing methods with tools such as long lines affect not only deepwater fish species, but also bird species. Currently, a major negative impact of commercial fishing comes from the by-catch of albatrosses and petrels in the long-lines in the North Pacific and in the Southern Ocean (Tasker et al., 2000). In correlation, high seas drift nets in the past, along with the common gillnet today, had considerable impacts on seabirds (Tasker et al., 2000). In terms of hard numbers, ecologists found it difficult to obtain a general census of all bird kills. However, some estimates were calculated for specific birds, such as murres, which expressed tens of thousands of individuals being killed each year by gillnets off the shores of Newfoundland and Labrador between 1968 and 2012 (Regular & Montevecchi 2013). In correlation to bird kills, other organisms such as whales and other marine mammals may also become entangled within fishing nets, which likewise cause unintended drownings (Johnson et al., 2005).

Other more indirect effects on ecosystems are more obscure. One particularly odd problem which arises from commercial offshore fishing is the onboard processing of fish. Fisherman then often toss the entrails and waste products of the processed fish overboard, which attracts large numbers of scavenging species such as the Great Black-backed Gull (Larus marinus), which is not only a scavenger but also a predator of small seabirds (Russell & Montevecchi 1996). As a result of these common handouts, Great Black-backed Gull populations increased along the Atlantic waterfront. One particular problem which potentially arose is that the increased gull numbers threatened local Atlantic puffin (Fratercula arctica) colonies, which not only had to endure declines in fish stocks of the area, but also increased predation as a result of increased gull presence (Russell & Montevecchi 1996). By overharvesting fish populations, people have positively increased some species within the ecosystem. However, such increase may prove indirectly negative, causing major decreases in other populations and communities within such ecosystem.

Atlantic Puffin

Great Black-backed Gull

Finally, secondary indirect issues which may arise as a result of commercial fishing is the processing and transport of such materials, including fish oil. Ultra-refined fish gels are sold most commonly in plastic bottles, which often results in increased landfilling of these products. Consequently, toxic plastics often are consumed by wildlife. Research suggests that while many species’ consumption of small numbers of plastic particles may not directly harm them, the presence of plastic within their bodily system often decreases food consumption, which becomes problematic for organisms which require large amounts of fat reserves to survive harsh seasons (Ryan, 1988). Additionally, plastic and other trash which are difficult to degrade and decompose are carried out into the oceans, polluting ecosystems far from the shore. In fact, circular oceanic currents often create large rafts of trash which eventually conglomerate into vast matts of “trash gyres” (Law et al., 2010). Production processes for both plastic bottles to house fish oil along with fish oil itself, often occur in large factories, which require enormous amounts of energy to efficiently separate wanted materials from the unwanted by-products. Such prominent machinery requires the increased utilization of energy output sources, which often is obtained from the combustion of fossil fuels. While demand for fish oil itself may be decreasing, changes in manufacturing and increased fish aquaculture may increase the necessity for fossil fuel usage. Likewise, even commercial harvesting techniques, which requires trawlers and boats, further increase the output of carbon dioxide and nitrogen oxides. These greenhouse gases, which trap heat within the atmosphere, create warmer temperatures, which collectively affect not only offshore oceanic ecosystems or inland marshes, but the entire biosphere. In combination with the elevated output of greenhouse gases, increased transportation of such materials may cause increases in environmental degradation. Isolated farms or commercial fisheries are required to transport the oil, whether refined or not, from one location to another, sometimes across the entirety of the country. Greater trafficking of materials may result in the creation of roads and railroads across formerly pristine, or near pristine habitat. Fragmentation of habitat and presence of roads often results in deterrence of various organisms, including large mammalian species such as elk (Cervus Canadensis) (Lyon, 1979). Isolation of large grazers within fragments of forest may result in depletion of forest cover as a result of over-browsing. Such issue may resonate beyond just elk and tree species and affect the growth and reproduction of the entire community. Ultimately, farming and commercial harvesting of fish oil expresses a variety of direct and indirect effects on the planet’s ecosystems. Some effects are limited to only their regions. Others however, greatly extend beyond local locations, affecting various ecosystems and communities around the globe.

Environmental Solutions and Conclusions

As demand creates issues for various ecosystems across the planet, scientists, lawmakers and the public are acting in different ways to mitigate such problems. Various methods in control of fish breeding and farming may aid in decreasing issues in terms of aquaculture. Likewise, training of farmers for cleaner farming techniques would curb pollution of water sources in the form of dumping of wastewaters into local sources. Also, fostering a more positive connection between individual citizens and governing bodies may elevate conservation abilities of a certain, especially contentious, region (Odada et al., 2004). Furthermore, limiting specific species from being targeted via incorporation of a prescribed data set (e.g. decline rate) can potentially be useful for simplifying management of complex multispecies fisheries (Alastair et al., 2011). Additionally, one recent, albeit controversial, method to potentially decrease the demand for products is the bioengineering of fish species like salmon, which involves inhibiting a myostatin. Myostatin normally itself inhibits the growth of muscle cells. However, modified salmon with repressed myostatin will continue to create muscle tissue, which results in larger mass (Roberts et al., 2004). This increase within muscle would allow for greater amounts of oil and meat production. Whatever methods are applied, the cooperation of various organizations, along with the public, would be needed to ensure the survival and health of oceanic fish stocks, along with the inland freshwater habitats. Again, perhaps as a result of conflicting research in the benefit, or lack thereof, of fish oil, the general demand and production of fish oil in itself has declined. However, usage of fish meal, which is a derivative product of the fish oil production process, is projected to increase from aquaculture (Bostock et al. 2010). Thus, it potentially negates the decreased demand for fish oil itself. Other sources for high amounts of omega-3 has been found in flax and similar seeds (DeFilippis & Sperling 2006), but data in regards to consumption of plant-based omega-3 over fish oil omega-3 is deficient. It is known, however, that projected increases in global temperatures as a result of climate change will significantly cause retraction and size of most fish stocks (Perry et al., 2005). If such proves true within the future, fish oil prices may dramatically increase due to such climatic shift. Unfortunately, continued practices of unsustainable fishing, farming, production and transport of, but not limited to fish oil in many areas, in combination with the shifting climate which result from the formers, may magnify the negative impacts on the diversity and the ecology of many ecosystems across the globe within the near and far future. Perhaps, through better understanding of the consequences of fish oil production and its hazards against the environment, we could ensure that there still would be such available biological diversity, and the products which result from such diversity, for future generations to enjoy and share, if we want to. And surely, we should.

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