Blue Green algaes - a plaque for our oceans.

I live in Denmark, and we are surrounded by water. Water that is partly salt and fresh. Salt water from Kattegat (the little ocean between Denmark, Sweden and southern Norway) and fresh water from the Baltic Sea. This combination of fresh and salt water, creates perfect conditions for huge fish populations, and trough history we have been a country with proud fishing traditions, that goes way back in time.
In old photos you could see fishing boats, loaded with fish from a day trip. Herrings, Mackerel, Cods, Horn fish, Salmons and a lot of other species - photos of a time long gone.
Today things have changed 200% - political decisions made in the name of progress, have created a sad development, regarding the water quality in the whole region.

The red crosses indicates dead zones for fish around Denmark's coasts in 1981!

Source:  environment studies from Århus University

Link: http://www.dmu.dk/foralle/Vand/Iltsvind/ 

I remember my youth, we caught heaps of fish every day with our rods, we could easy catch between 40-70 cods on a good nights fishing. Today the cod is more or less gone from the whole region, very sad. Have a look at this graph published in  2002, showing the development in the cod stock from 1971 - 2001 in Kattegat (a small ocean).

This graph shows the weight per 1000 tons caught cod (blue graph)
- and the weight in brood-stock (yellow graph)

Source: Munch-Petersen 2002

What happened more precisely?? - it's simple - the oceans became the sewers for every thinkable thing we needed to abolish - "out of sight, out of our minds".
One of the biggest problems in this region, are the many different political governments, all with a different sight on how to make the right priorities.
And sadly we humans always have a tendency to make money the most obvious first priority.The result in a long term, is of course an environmental chaos, with one big loser at the end - us humans, and our children in generations to come!!!.

Heavy Cyano bacteria (blue-green alage) attack, a warm summer in Denmark!!!!!

That caos is showing it's ugly face already - and very clearly!!! - simply because it is a fact that every warm summer we have, and these day that is quite often, a massive explosion of green algae is a reality - a disgusting reality!!!
Why does this happen - what is the biological explanation of this phenomena ??

Oxygen wastage is one of the mayor factors in this development, witch is directly related to what is disposed into our oceans, by our industry in general and huge farming industry in the whole region.
When nutrients and nitrogen from fertilizing and industry, are washed out into small rivers and lakes, and then runs in the oceans, as a result of a wet and rain full spring period, followed by a warm summer, then we get a dangerous cocktail, that turns our oceans into a " " thick green oatmeal" - witch is quite disgusting, to use a mild term !!!
These pictures are shot a warm summer day in 2006 i Øresund (a little ocean between Kattegat and The baltic sea), where I live very close by.
From a distance it looked like a "tempting Caribbean ocean" - but when you got close, it was a whole different story. The pictures speak for themselves !!!!!! :o/

The level of oxygen in a healthy marine environment should be around 8-10 mg. per liter ocean water. The definition of a serious oxygen deficiency is when the level drops to under 4 mg. per liter of sea water. If it drops even more, to a level around 2 mg. - then we are talking about a serious situation, and fish in these areas will try to escape, before they die!!.
This next graph from 2001 shows the oxygen level measured in Kattegat - 10 years ago!!!!!

Oxygen level per liter sea water from 1975-2000 in Kattegat!!!

The last couple of years we have been blessed with colder summers (I must be the only one in Denmark who want's cold summers!! :O) - and therefor we haven't had the same serious amounts of Green algaes in our oceans - luckily we also had a lot of windy summer periods, witch also is a very healthy combination for our water quality in general. And as I'm writing this blog right now, we have the coldest winter i over 20 years outside, witch is perfect for this development a well.
How this situation is going to evolve in the future are hard to predict, but I pay for a much higher political willingness among all of the countries in this region - but also for much more awareness among us humans as well, simply because we are the ones who vote for the politicians, who are going to make the necessary decisions, for the future perspectives of this region!!!

One thing is for sure - it is an extremely fragile situation!!! - and once we spoiled the ecosystem, it probably never will recover 100%.


We have to look at our oceans in a much more holistic way, and as very important recourse for all of us - and our future generations. Hopefully we will, but I'm not too optimistic, I must admit!!

Tight lines
 .¸¸.·´¯`·.¸ )><((((º>


If you want to learn more about the situation in the region - then here are some relevant danish links :
1) DMU's rapport archive on the subject (english version is available on site)  :  http://www.dmu.dk/Vand/Havmiljoe/Iltsvind/Arkiv/

2) PDF rapport (in danish) : http://www2.dmu.dk/1_viden/2_Publikationer/3_miljobib/rapporter/4_Iltsvind_Kap2.pdf 
3) A description in Gyldendals lexicon (in danish)  http://www.denstoredanske.dk/Natur_og_milj%C3%B8/Milj%C3%B8_og_forurening/Vandmilj%C3%B8,_spildevand_og_olieforurening/iltsvind