Not what it used to be.

Toxic river algae alert! A sign I have been seeing a lot in the Hutt Valley over the past 10 years. As a child, a summer tradition was to venture down to the river and go for a swim. I was a small, skinny child so getting into cold water was always such an effort. Each year I became more confident getting into the water. But when I was finally comfortable being submerged in the cold water, the river suddenly became covered in a mat of toxic algae and was no longer suitable for swimming. I was once told that the algae came from other rivers that was brought here by the horses involved in the filming of The Lord of the Rings but I think that was just hearsay. Recently, I read a blog post highlighting the causes of waterway pollution and was briefly reminded about the toxic algae that has been present in my local rivers and I wanted to know more about it. What is it? And why is there so much of it?

Algae is a made of many microorganisms called cyanobacteria. It is an aquatic organism that feeds via photosynthesis. It forms black or brown mats along the river bed covering most rocks. When I visited the river whilst the algae had no toxicity warning, it felt slimy, smelt dreadful and was very slippery to step on. When detached from the rocks its floats along the surface of the water; if exposed to dry conditions the algae will dry up and produce a musty odour.

http://www.radionz.co.nz/assets/news/11898/eight_col_ALGAELR.jpg?1387412678

Favourable conditions for extensive algae blooms include warm temperatures, sunlight, a low or stable river flow and nutrients. Being a type of bacteria, it thrives in warmer conditions. This is why the toxicity levels are much higher in summer months as the temperature of the water increases. Nutrients for the algae mainly include phosphorus and nitrogen. The presence of nitrogen in the waters is mainly due to nitrogen rich urea found in animal urine. Phosphorus is found in the ionic form phosphate, which clings to soil particles that wash into the river forming sediment. This makes the Hutt Valley River a perfect environment for Algal blooms to thrive.

The toxicity of the algae can kill dogs and livestock in less than an hour in extreme cases. Symptoms after ingestion can include lethargy, muscle tremors, fast breathing, twitching, paralysis and convulsions. This is a very cruel way to watch your beloved pet pass. In humans, symptoms of algae ingestion are not normally as severe but can include skin and eye irritations, gastrointestinal disorders, cramps and diarrhoea. Of course the concentration of toxins in the water do contribute to the symptoms that may develop but it is recommended to stay away from the river altogether.

It is so unfortunate that the algae blooms have made their way into my once great swimming locations. It makes me curious as to where such a toxic cyanobacteria came from in the first place. Was it always there? Does increasing pollution and temperature rises contribute to the increase of the toxic algae bloom in the river? I am constantly saddened and frustrated that the river is no longer a destination I can go to in summer.

Dangers of toxic algae . (n.d.). Retrieved from Environment Canterbury Regional Council: http://www.ecan.govt.nz/services/online-services/monitoring/swimming-water-quality/Pages/toxic-algae.aspx#causescyanobacteria-algal-blooms

Wright, D. J. (2012). Water Quality in New Zealand: Understanding the Science. Wellington, New Zealand. Retrieved from the Parliamentary Commissioner for the Environment: www.pce.parliament.nz/media/.../pce-water-quality-in-new-zealand.pdf

Expanding a single minded opinion.

Being a simplistic human being, I thought that it was a simple answer of placing a 10-year moratorium on commercial eel fishing. Done, species in rehabilitation and hopefully would no longer be a threatened species. I am a "hippie," when it comes to animals, SAVE THE ANIMALS NO MATTER WHAT! (unless that animal is a mosquito, then DEATH TO MOSQUITOES). As human beings, I believe that as soon as we came to earth we have caused a lot of harm to this planet; I think we should do whatever we can to save the earth now. I believe that something as small as saving one species will help to make a difference.

What I found interesting about assignment one is that although being strongly for placing a 10-year moratorium on commercial eel fishing, I was able to form a mutual argument and create an understanding of why one should not be placed. Commercial eel fishing is not a big industry in New Zealand like the dairy industry for example.

I thought that placing a temporary suspension on commercial eel fishing would not have a large effect on our economy. But the more I researched the more I understood that although commercial eel fishing is the largest contributing factor to the decline of Longfin eels, it is not the only factor. This helped me form another opinion that maybe temporarily banning commercial eel fishing was not the most effective idea.

In the early 20th century, Europeans had considered eels (especially large female longfin) pests as they would eat all the trout that the Europeans had farmed. This is when the Eel destruction campaigns had started. Fishers were encouraged to kill as many eels as they could catch. These eel destruction campaigns went on for approximately 30 years. Although these campaigns are no longer happening I believe that this is a major factor as to why we do not have many eels left with us.

Loss of wetlands is also another reason why eels are disappearing. It is estimated that only 10% of wetlands remain in New Zealand to what was originally here 200 years ago when Europeans arrived. The construction of Hydro dams also have a high eel mortality rate with generally no female eels surviving when entering a hydro dam.

I do agree that placing a 10-year moratorium on commercial eel fishing will be the most effective way to help ensure the survival of longfin eels. But I do believe that this is not the only way about saving the species. Alternatives that I have thought of are:

• placing a 10-year moratorium on only longfin eels might be effective. 
• reducing catch limits for longfin eels.
• increasing conservation status of longfin eels
• creating more habitat and wetlands

"Eels are a taonga and have been the lifeblood of many iwi and hapu for generations."
                 - Chairman of Te Wai Maori, Ken Mair 

Jellyman, D. (January 2012). The status of Longfin eels in New Zealand - an overview of
             stocks and harvest. National Institute of Water and Atmospheric Research.

Wright, D. J. (December 2014). Update Report: On a pathway to extinction? An investigation into the status and management of the longfin eel. Parliamentary Commissioner for the Enviroment.

Is a 10-year moratorium a good idea?

The endemic longfin eel. Native to New Zealand. It once thrived in our freshwater lakes, rivers and streams. Slowly the eels population has been declining. The longfin eel is now an at risk species and faces extinction if action to save our eels does not take place soon. A 10-year moratorium on commercial eel fishing has been proposed to help ensure the survival of this species. For my position paper I chose to highlight all the factors that have been contributing to the decline of the eel to help form an opinion based on these factors.

Acknowledging that although commercial eel fishing might be one of the more obvious reasons why Longfin eels are disappearing from our waters. It is not the only reason the eel population is slowly declining. Things like habitat loss, infection & illness and hydro dams also contribute to a reduction in Longfin eel populations.

A report written by the Parliamentary Commissioner for the Environment outlined the main reasons how Longfin eels have become a threatened species. She felt very strongly to help ensure the survival of the species. Three recommendations were made based off her investigation. The first was to suspend all commercial eel fishing. The commercial eel fishing industry is not a very large industry in New Zealand so suspending commercial eel fishing will not have an outstanding effect on our economy. The second recommendation was for the Minister of Conservation to increase the protection of longfin eels and other threatened migratory fish. The Commissioners final recommendation was for the Ministry of Primary Industries to establish an independent review panel to allow for greater transparency and public trust of scientific advice. It was in the Commissioners best interest for the survival of the longfin eel, and I agree that her first recommendation will be the most logical, quickest and effective way to ensure the survival of this species.

The second source that highlights the Minister of Primary Industries views the status of the longfin eel was the updated report initially written by the Parliamentary Commissioner for the Environment. The minister's response to the first recommendation suggested that from the information made available to him that there is no sustainability concern to warrant closure of the commercial longfin fishery. He believes that there are other ways to sustain the population of longfin eels then just suspending commercial eel fishing altogether. The Minister made suggestions implementing a new way to manage longfin eel stocks including:

• a review of catch limits for longfin eels,
• consideration of separate South Island longfin and shortfin stocks,
• introduction of abundance target levels, and
• improved information from the commercial longfin eel fishery.

The final recommendation given to the Minister had me questioning where he gets his scientific advice and management decisions. This has lead me to believe that the Minister does not feel that the longfin eel as at risk as it is. Because of his "lack," of information the Minister of Primary Industries does not believe suspending commercial eel fishing is not necessary to ensure survival of the Longfin eel.

Wright, D. J. (April 2013). On a pathway to extinction? An investigation into the status and management of the longfin eel. Parliamentary Commissioner for the Enviroment.

Wright, D. J. (December 2014). Update Report: On a pathway to extinction? An investigation into the status and management of the longfin eel. Parliamentary Commissioner for the Enviroment.