Monday, 1 January 2018

The Theory of Algae Bloom in NZ Rivers.


Kia ora and welcome to The Mad Blogger's latest article.  Yup Why Cow Poop, animal urine, and phosphates are NOT to blame for Toxic Algae Bloom in our rivers. Actually more importantly our South Island rivers.

Clarification -  This condition was evident before Dairying in the Both Islands.  And if one looks even deeper there have been a dearth of blooms in all rivers that are shingle base rivers for some time. In the North Island the rivers that have featured were all south of the Central Plateau (Taupo, Manawatu, Ruamahanga, Northern Hawkes Bay and Otaki and Hutt)  I doubt very strongly that these rivers have blooms based on Dairying.



The South Island has greater bias towards also suffering blooms in shingle based rivers.  Nearly all South Island rivers have had blooms and quite badly. So is there another reason?

Well simply - yes there is.  Back in the 1900's Trout (Rainbow and Brown) and Salmon were placed in our rivers for sporting reasons.  Basically there was a wholesale ecological time bomb let loose and the rest is history.  These fishes raped a very finely balanced ecosystem.  Trout had only one predator, Man (in the form of a Fishermen (and the occasional Iwi) and had a huge system that they were comfortable.  Koura (Freshwater Crayfish) and Inagna and Cockabillies were all on the Trout menu.  Double that with the huge disruption on ecosystems and lack of whitebait getting up stream and the picture shifts.  These integral parts, Koura, Inanga, Cockabilly and Whitebait have to play is the reason rivers are (algae)blooming - they have no way to basically feeding on algae.  I doubt Trout and Salmon eat algae??



Solution - if O'Possums are a scourge on the landscape ecosystem and damaging Beech Forests,the same goes for Trout/Salmon.  The proof is there if you just look a little closer for the truth.

Feel free to have your say.

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