Tiistai 26.1.2021 klo 18:04 - Mikko Nikinmaa
In the age of Coronavirus Pandemic, the news has virtually nothing else now that Trump is not in the White House any more. In the news it is completely forgotten that environmental scientists warned about pandemics becoming ever increasing threat because of population growth and increased land use already 25 years ago (Daily, G. C., and Ehrlich, P. R. 1996. Global change and human susceptibility to disease. Ann. Rev. Energ. Environ. 21, 125–144). However, the link between environmental distraction and human diseases is rarely brought forward in media, although presently three quarters of new human diseases result from microbes being transferred from animals to humans.
Bradshaw et al. (Bradshaw et al. 2021. Underestimating the Challenges of Avoiding a Ghastly Future. Front. Conserv. Sci. 1:615419. doi: 10.3389/fcosc.2020.615419) have recently written a perspective article about the environmental problems we currently have. The major point is that, although the scientific evidence clearly shows that the present environmental actions are not adequate to enable sustainable development, the political and economic circles still think that environmentalists are overblowing the problems. In fact, the populists everywhere have gained ground everywhere by saying that nothing needs to be done. As they say: “The predominant paradigm is still one of pegging “environment” against “economy”; yet in reality, the choice is between exiting overshoot by design or disaster—because exiting overshoot is inevitable one way or another.” Overshoot means that at present the planet’s resources are overused, human population is too big, and land use causes biodiversity decrease.The economic and political circles are very worried about leaving monetary debt to future generations, although that is just numbers on databases, and can be cancelled if one so wishes. In contrast, environmental destruction can make life of future generations very difficult, yet policy makers do not think that the life of future generations needs to be thought about by carrying out environmental actions.
Maanantai 30.11.2020 klo 15:07 - Mikko Nikinmaa
Climate Change has an anthropogenic component: the use of fossil fuels increases the carbon dioxide level, which has an increasing effect on the temperature of the Earth’s surface. It should always be kept in mind that this is an overall effect. In a specific location temperature can even decrease, because the flow of air becomes unpredictable, i.e. cold air from the poles can flow to completely new directions. Also the present extinction wave is largely human-induced, and is caused largely by increased human land use, pesticide use, overfishing etc. In both the large human population and the strive for economic growth are decisive. Greed is the main fuel for destroying the world. “I want more, and others may not share what I have got.” This attitude keeps pushing us towards a catastrophe.
People denying human role in climate change always point out that there have been temperature variations already earlier without any human influence. This is true, but in most cases they have been much slower than the presentone: what happened in 10000 years millions of years ago takes place in a 100 years now. The people denying human influence on climate change often deny also the existence of extinction wave, there have been five extinction waves before, and they have all been caused by natural catastrophes: meteors colliding to Earth or volcanic activity.
In Geology, Kaiho et al. recently wrote an article “Pulsed volcanic combustion events coincident with the end-Permian terrestrial disturbance and the following global crisis” (https://doi.org/10.1130/G48022.1), which tries to put together the events which were associated with one of the mass extinctions in Permian period. It appears that during that time the temperature was elevated. The extinction wave started, when an intense volcanic activity started. However, it would possibly remained much more reduced than it came to be, if there had not been large fossil fuel deposits close enough to land surface to start burning as a result of volcanic eruptions. The fossil fuel fires have much higher temperature than normal wood fires with the result that a specific molecule accumulates much more. The authors made their conclusion about volcanic eruptions causing significant fossil fuel fires on this. So fossil fuels may have played a role in extinctions already before.
Torstai 10.9.2020 klo 14:10 - Mikko Nikinmaa
The Living Planet Report 2020 was just published (can be downloaded from https://livingplanet.panda.org/). It is sad reading: the vertebrate populations have decreased globally by 68 % from 1970.The most marked decreases have occurred in areas with high population growth and least in areas with low population growth. In South America the decrease of animal populations is 94 % as compared to 1970 and in Africa 65 %. It is no surprise that the animal populations decrease most in areas with high population growth, since there the changes in land use are greatest, and changes in land use account for more than half of the changes in animal populations. Notably, about 75 % of ice-free land area is nowadays impacted by humans, and the percentage of wilderness decreases with population increase: wilderness remains in Arctic areas and deserts, which are uninhabitable.
Although it is clear from the Living Planet Report that population growth cannot continue, if we are to have sustainable future, the economic circles say that future of economies depends on population growth. This thinking is like increasing the speed of the car, when you know that a collision to a brick wall is imminent. Shouldn’t we instead start modifying our economic theories towards a regulated population decrease? If we did that, both biodiversity could be maintained and climate change could be stopped. Not a bad heritage to future generations. I bet they would accept this even if it was done with loans: it is much better to have healthy environment and high debt than to have no debt but unhospitable Earth.
Maanantai 10.8.2020 klo 18:01 - Mikko Nikinmaa
Climate change, Covid-19 pandemic, racial discrimination, populistic movements, inequality, biodiversity loss – the list could continue almostforever. The humankind has problems, and the problems are caused by greed and selfishness. That is best seen in the increasing nationalistic populism. We should only take care of our own group. However, why should we broaden our thinking as far as the nation state. There are usually millions of people in nation states – why should we care of people living in different areas, they are certainly taking advantage of us even if they are living in the same nation as we. Shouldn’t we restrict caring about others to our immediate family. Anyone who looks at all different is not worth caring. That is the basis of any discrimination, we can always find a reason to divide people: according to skin colour, language, religion, gender, disability etc. When the people are labelled to different from us, we do not need to think about how their conditions could or should be improved, but can label them rapists, thieves, murderers, terrorists, whose sole aim is to disturb our life.
Thinking of other people that way, the further they are from us, the less we need to care, makes it possible to be greedy – we do not have to care about their conditions as long as suppressing them gives us more riches. Or if we utilize them, they are not our equals but slaves: why would we care as long as we get cheap t-shirt, can dispose of our toxic wastes cheaply to developing countries or can eat cheaply in ethnic restaurants, or get sexual satisfaction. We in the rich world have been able not to care until recently: the Covid-19 pandemic, climate change, biodiversity loss and environmental pollution have now made many of us to realize that the earth has limits and that we have reached them. Further, it is obvious that inequality across the world cannot continue. To enable sustainable development, we rich need to decrease our consumption, and population increase needs to stop.
Unfortunately, there are still a lot of greedy rich people (and less rich ones), who refuse to see that anything needs to be done. Invariably they are reverting to the past, more or less saying that the coal and oil consumption is 1960s didn’t cause anything, so why would it now. The difference to today is that the energy consumption today is manyfold per person as compared to 1960s and we are four times as many. If we could go back to the past, I would gladly do it. None of the present-day problems would have taken place with the population and resource use of that time.
Thus, the change that is needed is the way of thinking. Instead of greed and selfishness, caring and compassion should be the leading qualities. Environmental problems cannot be solved, if the getting rich-me first-attitude persists.
Maanantai 20.7.2020 klo 20:08 - Mikko Nikinmaa
The most important reasons for all the environmental problems, climate change, biodiversity loss, loss of arable land, overfishing and pollution are the increase of human population combined with the strive for every human to be able to consume more. Thus, to be able to have sustainable development, the primary goal must be to stop population growth. Hitherto it has been estimated that the growth of human population continues to at least 2100, although the growth rate is decreasing. By 2100 there would be more than 10 billion people on the earth, if no catastrophes occur before that. In view of the gloomy predictions, it was refreshing to read the article by Vollset et al. in Lancet (July 14, 2020; https://doi.org/10.1016/S0140-6736(20)30677-2). They estimate that the population reaches a maximum of 9.73 billion by 2064 and thereafter decreases so that by 2100 the population is 8.79 billion. The population decreases everywhere except in Africa especially in Sub-Saharan Africa. The population increase seems to continue there up to 2100 with the consequence that Nigeria will be 2nd most populous country in the world by 2100. Also, out of the world’s population, about 3.8 billion will live in Africa.
The economic systems virtually everywhere are based on population growth. Thus, one sees in European newspapers big headlines about how terrible the decrease of birth rate is. However, to enable sustainable development, that is what needs to take place. Since the population growth occurs in area from which emigration to Europe is feasible, European countries should, for their own sake, start thinking about immigration as an asset, not as a burden. This requires a change of many people’s attitude.
However, even the 8.8 billion population is too large for sustainable living. Even if climate change with new technologies could be stopped, the need for food, biodiversity loss and pollution continue. The population can be further decreased, if the education, especially women’s education is improved. It is clear from the enclosed figure that lifetime fertility (y-axis) decreases with the number of years of education. With education improved and birth control applied, the human population would decrease to about 6 billion by 2100, i.e. be about a quarter less than today. That would certainly be sustainable, so there is a ray of hope, which is achievable.
Maanantai 13.7.2020 klo 16:28 - Mikko Nikinmaa
As a child, one of my favourite books was a book of wild animals – I read all the stories of antelopes in Africa and looking at the photographs hoped that one day I would be able to go there. Almost every day I went birdwatching: curlews, whinchats, ruffs and ortolan buntings were common. As a scientist I was able to see sea otters, elephant seals,
echidnas, and finally was able to fulfil my childhood dream, see antelopes in Africa. The incredible variety of animal life in different parts of the world is something that I hope our grandchildren and their descendants are able to see. The hopes of a nature lover for a heritage to future generations may be somewhat different from those of economic circles.
As the major reason for nations not taking loans, politicians usually state that we don’t want to leave future generations debt. This has also been stated as a reason why the European Union should not give grants to the hardest hit nations. If the big relief package of the European Union is not accepted, the Union can break up. For the environment this would be a catastrophe, because EU is the only major economic player, which has environmental questions reasonably high in its agenda. The European nations as relatively small individual nations would be forced to accept the conditions that USA and China, and to some extent Russia, Brazil and India, demand. For the environment, this would be terrible news.
We have now come to a situation, where environmental conditions and national debt are choices of our heritage to future generations. If loans are taken in order to invest on actions that improve the future state of environment, I am quite sure that future generations would say: “Please, take loan. It is only money, whereas sustainable environment is much more.” I am also quite sure that they would say: “Please, accept the European Recovery Plan, it is the only way to maintain a responsible environmental player as a major economic factor.”
It is not leaving debt to future generations any more, it is choosing if we give them a liveable environment or no debt. I think debt is better than spoiled Earth.
Coronavirus Pandemic and Climate Change are Different Facets of the Same Problem: the Overuse of the Earth
Perjantai 17.4.2020 klo 19:29 - Mikko Nikinmaa
Coronavirus Pandemic and Climate Change are both different aspects of the same problem: our overuse of the Earth. Further, neither problem can be solved thinking nationally: both viruses and pollutants cross national borders with no problems. Even if hermetic closure helps to limit the spread of the current Coronavirus, without solving the problem with the overuse of the Earth there will be a next virus attacking man in the future. It is not by accident that there have been several worries about pandemics in 21st century, Ebola, SARS, swine flu, at the same time that clear Climate Change signs have been seen. Hitherto international cooperation has enabled us to avoid the worst possible outcome of the diseases, but this time it appears that the ongoing surge of nationalism has meant that instead of thinking what would be the best way to combat Coronavirus globally, one has resorted to national solutions.
The overuse of the Earth can be divided into three components, which all must be addressed in order to avoid future pandemics and combat climate change. The three components are population growth, excessive consumption by the rich and inequal wealth distribution. Quite often when one discusses with some climate activists, they claim that including population growth is virtually racism, as it “blames” the world’s poorest, who have caused little of the climate problem. On the other hand, some people from rich areas maintain that the climate problem is solely caused by population growth, as the use of fossil fuels in for example Europe has decreased for the past 30 years. Both are wrong, because they come together as a result of wealth inequality.
The reason why population growth is an ultimate problem for both Coronavirus Pandemic and Climate Change is manyfold. There are now about eight billion people living on the earth. The sheer number of people inevitably leads to increasing portion of the Earth to be used for human habitation and food production. Agricultural practices have led to land deterioration – loss of fertility and erosion, which increasing amount of land is needed to feed people, and this need is compounded by the population growth. As a result, natural habitats are changed to human use, which means both that the carbon dioxide sinks of forests decrease and that animal biodiversity gets smaller. Also, wild animals have less space and must increasingly be in close proximity to humans and domestic animals. At present, the total biomass of humans exceeds that of wild animals and the biomass of farm animals is far greater. Further, humans everywhere like to eat meat, and in most places the only way to get meat unspoiled to the customers is to have animals alive until someone buys their meat. The animals, which are sold are often wild homeothermic animals, birds and mammals. Zoonosis – a disease transmitted from animals to man – is a bacterium or virus of birds or mammals, which mutates enough to enable transmission to humans. The vegetarians naturally point out that if eating meat were stopped, both the possibility of zoonoses would disappear and climate change be reduced. Zoonosis risk would decrease markedly, but not disappear, since wild animals would still be in close contact with humans because of the diminishing area of natural environment. Climate Change would be combatted, as the carbon footprint of meat production is much larger than if vegetarian diet is used. One must remember, though, that eating fish or shellfish or terrestrial poikilotherms has only slightly higher carbon footprint than vegetarian diet. Also, there are currently no known transmission of microbial pathogens from poikilothermic animals to humans.
Although rich countries at present are decreasing their carbon dioxide emissions, the present use of Earth’s resources is severalfold compared to poor areas. Further, to reduce costs, a lot of the cultivation of plants in poor areas are done to produce goods for rich nations. The cotton and avocado cultivation uses most of the water in arid areas and is almost exclusively done for export to rich nations, and the sales do not benefit the local population. Also, the rich nations export much of their wastes like plastics and metals to poor countries, where they somehow disappear (and are found in, e.g. plastic waste gyres of the oceans); the companies from rich countries make profits on products (e.g. clothes) manufactured in poor countries with virtually no pollution control. In conclusion, we in rich nations owe a lot of our wealth to the poor areas. Consequently, we cannot say that they would not be allowed to want to have similar standard of living as we do.
This leads to the final part of the problem, wealth inequality. Correcting that is needed both to reduce the risk of future pandemics and to combat climate change. We in rich nations could easily decrease our resource use and consumption, as the present Coronavirus lockdowns indicate. The decrease could be transferred as wealth to poor areas, and the technological progress used to help everyone. If we continue with our greedy economic globalism or resort to nationalistic policies the humankind, even we rich, goes under either because of another pandemic or climate change.
Tiistai 26.11.2019 klo 12:40 - Mikko Nikinmaa
Among the 11000 other scientists, I was among the signatories in the article authored by William Ripple et al. It was published in BioScience in early November, and attracted pronounced media coverage. Since the article is open access, here is a link to the published paper. Please, read it (and if you know anybody who doubts anthroponic effects on climate, get them to read it): https://doi.org/10.1093/biosci/biz088
Perjantai 1.11.2019 klo 18:38 - Mikko Nikinmaa
Climate change is a question that has filled the media because of its potential effects on all aspects of life on the Earth. In the coverage of climate change, it has become THE PROBLEM. If we can solve it, life can continue with small disturbances. In view of this, different technological solutions to combat carbon dioxide increase have been offered. Mainly they concentrate on stopping the use of fossil fuels, changing the food preferences, removing carbon dioxide from the air and stopping overconsumption. The good news is that there are technological and societal solutions for stopping climate change without a need for drastic changes in everyday life – it only needs some adjustments. The worrisome problem is that there appears no sign of change in attitudes of economic leaders. In the recent report of World Economic Forum environmental questions were not even mentioned as factors to be taken into account, when considering economic development.
The bad news is that even if the presently gravest symptom of Earth’s overuse, the climate change, can be stopped as a result of technological advancements, that does not stop the real problem: the overuse of Earth. There are two major components of this, population growth and consumption growth. Population growth demands more food production, and the increasing population in the presently poor areas will want to improve their living standards closer to, e.g., Europe. However, the food production with present agricultural methods has decreased the fertile soil by 50-70 %. Also, the present type of food production requires insecticides, herbicides and other pesticides, and artificial fertilizers. Already with the present population the pesticide use causes decrease of beneficial insect populations, which are required for the growth of berries, fruits and many oil-producing plants. So one would need to revert to environmentally friendly agricultural production. The problem is that consequently the production will decrease and will be unable to feed the presently increasing population. Because the fertility of land decreases, also new areas need to be taken to agriculture. This is difficult, since most of arable land is already in use. The increasing population also needs more space, and consequently habitation takes agricultural land and forest. As a result biodiversity decreases.
With regard to consumption, it is difficult to decrease environmental pollution even if recycling and water treatment technologies are effective. There are always people, who do not follow good practises, and developing areas do not see the treatment of wastes and water purification as priorities. Consequently, environmental pollution continues to increase throughout the world. Both aquatic and terrestrial organisms will be affected.Thus, one can say that even if there were no climate change, other drastic symptoms of Earth’s overuse would be in the news. The basic problem is that limitless growth is the basis of economy in a planet which clearly has limits.
Lauantai 11.5.2019 klo 18:35 - Mikko Nikinmaa
The Our Planet documentary series by David Attenborough in Netflix (www.ourplanet.com) is incredibly good, and will probably be the most popular pro-environment series that has recently been published. When watching it a couple of things must be remembered. Although climate change is of a huge concern, the short-term solutions alleviating it will not solve the basic problem, which is our overuse of the planet. Climate change is just one symptom stemming from the facts that there are too many people who are overusing Earth's resources. In November 2, 2018 I wrote a blog, where pictures of human population change and the increase of world's carbon dioxide were side by side. And they could be superimposed. Further, although it could be possible to severe the link between human population and carbon dioxide production in the short term, the vicious circle between population growth, resource overuse, pollution and climate change still exists in longer term because of the following.
Human population needs to be fed. The intensive agriculture with artificial fertilization and pesticide use has increased the agricultural production per hectare to 5-10 times the crops obtained before "industrial" agriculture. It has been estimated that without the use if artificial fertilization and pesticides the maximal size of human population would be 2-3 billion. However, Nature presently strikes back. Fertilization pollutes our waters, pesticides kill pollinators and the microalgae of the seas. The results arte that aquatic pollution is decreasing the ability of algae to photosynthetize. The aquatic algae have contributed to 50 of the carbon dioxide sinks of the world. Now it is estimated that carbon dioxide fixation by them has decreased by 20 %. Aquatic pollution thus drives climate change.
Pollinating insects die as a result of insecticide use. Since about 2/3 of all the food plants need pollination by insects, this as such reduces the possibilities of increasing agricultural production by increased insecticide use. As the productivity per hectare cannot be increased, more people means that forests must be cut to obtain agricultural land. At the same time old agricultural land is becoming infertile, and changes in precipitation aggravate the problem. Cutting the forests causes biodiversity loss and since forests are more effective carbon dioxide sinks than agricultural lands, aggravates climate change.
Apart from cutting rainforests, the most pronounced biodiversity losses are caused by overfishing. Most fisheries at the moment are unsustainable, and aquaculture does not help the situation, as most of the fish feed is made from fish. So, the only change that happens is that for human food less preferred species are caught. An additional problem with aquaculture is the use of antibiotics and pesticides, which affect marine life and be one component of generating antibiotic resistance in the environment.
Besides the decrease of marine biodiversity, especially the large amount of plastic waste in the oceans is an anthropogenic problem. Here an important step forward was taken a day or two ago, whem most countries in the world agreed that plastic waste may not be exported. This will generate national recycling of plastics. Notably, Trump's USA did not sign the agreement. The present government of the USA has been very consequent in the anti-environment actions, opposing any actions which could be seen as trying to improve the state of environment. The US government after Trump will have much to do to reverse the anti-environmental actions of the present government.
If it weren't for plastics, it is likely that there would be other tash all over the place. Different materials, which could be recycled are just thrown away. For example, much of the metals could be reused which would much reduce the need for mining and theeby overuse of world's resources.
In conclusion, we would need to find ways both to decrease the human population and the amount of energy and resources used by a unit human. Changes in the first pertain especially to developing countries and in the second to inhabitants of traditional industrialized countries. One cannot think in terms "we will do nothing unless the others do their share", because that is a certain way to go to catastroph.
Sunnuntai 24.3.2019 klo 19:49 - Mikko Nikinmaa
We need to live in this planet. There is no alternative universe, where we can jump to if we overuse the resources of Earth. Although climate change is the single topic that has caught general attention, it is no more than a symptom of the general sickness of Gaia. There are several other symptoms that will also unattended make life problematic.
In all of this, the major problem is that the decision makers were young in the world that didn't have any of the environmental problems, which the teenagers today are faced with. A week ago schoolchildren around the world demonstrated against climate change. Not surprisingly a lot of people in my generation said that they are just taking time off school. Their thinking is not idealistic or important. - People completely forget when saying this that when we were young, we demonstrated against Vietnam War, were worried about population growth and chained ourselves to dredging machines, which were spoiling lakes for economical land use. In fact, many of the problems associated with climate change would not be acute, if we had, in addition to demonstrating, used our working life to solve the environmental questions.
The major problems are the large world population, and the very uneven distribution of wealth in the world. Together these generate much of the refugee problem, which cannot be solved by closing our borders, building walls, and decreasing foreign aid. On the contrary, increasing foreign aid is the only possible solution. People would not move to rich countries, if life in their living place were tolarable. Also, schooling of women is by far the most effective way of decreasing population growth. Further, we in the rich North lived quite happily 50 years ago, when our standard of living was only a fraction of what it is today.
This partial solution requires that we, the generation in power, stop thinking in the old ways, and admit that one has to do things that cost. We cannot keep taking from our children's well-being to be able to go towards a crash in first class.
Lauantai 19.1.2019 klo 12:20 - Mikko Nikinmaa
Out of the world's area, 71 % is sea and 29 % land (including inland water). Out of this 29 %, about 71 % is habitable. About 50 % of this habitable area is used for agriculture: the area is much larger than that occupied by real forests (36-37 %), scrubland (10 %, much of this is eroded farmland) or urban areas (2 %). Most of the agricultured land is pasture (77 %). Thus, all the crops for human food are cultivated in less than 25 % of the agricultural area.
The absolute amount of land that is used for agriculture is not increasing any more. New land is taken into use more or less in the same area as is lost as cultivated soil becomes infertile. The new cultivated land is mainly obtained through deforestration in the tropics. This means the loss of biodiversity and a decrease of the carbon dioxide sink of the forests.
Although the human population has increased markedly in the past fifty years, the amount of feed per capita has also increased. This has happened via "green revolution", the increased yields per area partly as a result of the use of artificial fertilizers, irrigation, pesticides and high-yield strains of cultivated plants. There are, however, several downsides of the high-efficiency agriculture. First, it depletes the soils, which can become uncultivable. However, even if the fertility of the soil can be maintained with the use of artificial fertilizers, they leach in the inland waters, which are a limiting commodity anyway, and their eutrophication generates all sorts of problems for aquatic life. Irrigation improves the immediate water availability in cultivation, but it leads to overall decrease in ground- and lake water, as seen in Aral lake, Israel and California. Decreased groundwater levels can be one of the reasons for the Californian wildfires. Artificial fertilizers are, further, mined, and easily reached sites are more or less depleted. The use of pesticides is counterproductive, since non-target species are affected. Because of marked insecticide use it has already been suggested, and the results indicate clear correlation, that the decrease of beneficial pollinator populations is caused by the indiscriminate use of insecticides. The above examples indicate that the yield increases of "green revolution" may be temporary, and carry a heavy cost to the environment.
In view of this, it appears that there are three possibilities to decrease the need for inreased agricultural land use. All of these are also important ways to combat climate change. The first is to limit population growth. To do this, especially women's education should be improved. The second is to decrease the number of farm animals, especially ruminants whereby the proportion of agricultural land as pasture fields can be decreased and crop cultivation increased. This will decrease the amount of methane produced. Third, production ofedible plants close to their sites of consumption, e.g., aquaponics in cities, should be encouraged. This decreases transport distances for agricultural production.
Torstai 20.7.2017 klo 13:53 - Mikko Nikinmaa
Fishermen always complain that they are allowed to fish too little and fish biologists have alerted people to the fact that politically decided fishing quotas are too big. If fishing cannot be reduced, several preferred species will become extinct in the next hundred years. The lobbying groups for fishing industry have hitherto been able to convince politicians that putting money in new and effective fishing vessels and having fishing quotas enabling overfishing are good ways of preserving employment - one need not care if preferred fish disappear from nearby areas. With new vessels obtained, e.g. with European Union support, one can have longer fishing journeys than earlier.
It appears that a significant problem with fishing is that the identification of fish by fishermen is poor. If one is approaching the maximum allowed quota for one species, the fish are just marked to be of species, where quotas are not near filling. Giving this type of misinformation varies a lot depending on which country the fisherman is from.
However, even in the interests of fishermen, the fishing quotas should be set on scientific, and not political grounds. Further, the quotas should be followed. And actually, increasing the use of aquacultured fish with land-based feed and effective removal of wastes, is the way forward. All these points are important in order to have fish diversity also for future generations.
Maanantai 3.4.2017 klo 13:06 - Mikko Nikinmaa
Fish is, in principle, health food, and also good in terms of climate change. As insect eating has recently been advocated as an environmentally friendly way of actually eating meat, one needs to point out that from energetic grounds fish eating is just as good. Both insects and fish are ectothermic animals, which convert feed to meat at much higher efficiency than cows or swine, because no energy needs to be wasted to maintaining body temperature.
So, it is good to eat fish, but should it be wild-caught or cultured? The world's seas are heavily overfished. The gloomiest predictions estimate that close to half of commercially fished species become extinct within the next century. Despite the overfishing, several nations and the European Union have given large funds to the development of fishing fleets, and more effective fishing gear. At the same time the same instances have pledged to maintain the biodiversity. So, the actions are in fact opposite to promises and only serve to speed up the decrease of biodiversity. In addition to fishing causing the exctinction of species, the problem with wild-caught fish is aquatic pollution. Most pollutants are taken up and remain in the bodies of fish, because they are hydrophobic, whereby their preferred site is the body and not water. Many of the pollutants further bioaccumulate along the food chain.
So, eating wild fish is, in principle, a worse alternative than eating cultured fish. However, there are several things that make the present aquaculture practises problematic for ecologically responsible fish-eater. First, most cultured fish are carnivorous, and their feed largely consists of fish flour. So, in such a case the big fishing fleets will continue to decrease the fish diversity, now not to get food for humans, but to get resources for feed factories. The only sustainable way is to replace some of the fish flour in feed with plant product. This is a direction to which several fish feed companies have recently gone to. Second, aquaculture causes local eutrophication because of the feed and faeces, which have high amounts of nutrients. The way of prevent this would be to have aquaculture facilities separated from general aquatic environment so that all the water used could be purified. One should here point out that the cultured fish do not produce more faeces than the natural populations - the difference is that they are concentrated in much smaller areas. Third, the use of antibiotics and other drugs in aquaculture facilities is high, because parasites and diseases are much more prevalent in the dense aquaculture populations than in the natural populations. For improvement of situation with regard to this, it would also help, if the aquaculture facilities were separated from natural wateeeeer flow. Also, the use of antibiotics should be discouraged.
In conclusion, it is possible to make aquaculture environmentally friendly, but after that is done, cultured fish will not be the cheapest food that can be found. But we should be ready to use some money to use ecologically sustainable foodstuffs.