Monday, 13 June 2016

Algal Blooms from Fish Farm Sewage - Chile

It is not new that fish farms cause algal blooms, particularly in Chile, because of their sewage, extra feed, and so on. So, the industry is largely to blame for the deaths of 25,000,000 fish, added to the effect of dumping more than 75,000 mt of dead fish, fifty miles to sea in Chile. And you will note from my News Bites post that the El Nino has been ruled out of being a cause by a scientist in the area.

Claudette Bethune, scientist:

"Same old story, a 2006 publication shows the algae bloom legacy of salmon farms in Chile with pumping nitrogen and phosphorus from sewage into the ocean: "The occurrence of harmful algal blooms resulting from the input into coastal waters of nitrogen from salmonid farms is another major topic of concern in Chile. Harmful algal blooms have been recorded in Chile during the past three decades and have affected human health and natural and cultured marine resources (Table 1). The first instances to affect human health were reported in 1970 and 1972, and involved the species Dinophysis acuta and Alexandrium catenella; in 1993, diatoms of the genus Pseudo-nitzschia were implicated in a harmful algal bloom. These algae are sources of diarrhoetic, paralytic, and amnesic shellfish poisons, respectively. A. catenella blooms have affected Chile's austral region (42°S–52°S), whereas D. acuta and Pseudo-nitzschia have resulted in blooms in various enclosed coastal areas (Table 1). The algal species that have affected marine resources include Dinophyceae (Prorocentrum micans, Gymnodinium cf. cloroforum, and Gymnodinium spp.); Bacillariophyceae (Leptocylindrus minimus, Chaetoceros convulutus, and Chatonella sp.); Raphydophyceae (Heterosigma akashiwo); and Chrysophyceae (Dictyocha speculum) (Table 1).""

Here is the abstract for the paper:

"The production of farmed salmonids in Chile reached 550 000 t in 2004. The industry is considered to be consolidated, but with potential for further expansion to the south into pristine coastal areas. The environmental impacts of the salmonid farming industry in Chile were reviewed in 1996, and evidence at that time did not suggest significant adverse effects. However, after almost ten years of sustained growth, current evidence indicates that significant loss of benthic biodiversity and localized changes in the physico-chemical properties of sediments have occurred in areas with salmonid farms. Furthermore, the presence of these farms significantly increases in pulses the density of dinoflagellates. Data suggest that escaped farmed fish may have an impact on native species, although their survival in the wild appears low. The abundance of omnivorous diving and carrion-feeding marine birds increased from twofold to fivefold in areas with salmon farms compared with control areas without them. It is urgent that an ecosystem approach be implemented to assess all impacts of salmonid farming on coastal ecosystems in southern Chile."

So, fish farms have a causative role in the killing of their own fish, as well as the environment. The paper also goes into that the industry, looking for cleaner water (meaning water they have not dumped sewage into for decades) wants to move south into Patagonia. Sad, Sad. One of the world's most magical, pristine areas, to be fouled by fish farms.

Oh, and if you scan my News Bites post, you will find that Marine Harvest is currently bullying the Chilean government regarding the regulations it wants to put in place, saying they don't understand fish farming. This is the same thing it has been saying to the Norwegian government for 40 years. Read the Kjersti Sandvik book, Under The Surface, for details and references covering the history of development in Norway. Nice try Marine Harvest - who, you may be surprised to hear, trumpeted how they operated under the strictest laws in the world in Chile just a year ago. Sure. Chile is widely acknowledged as the dirties country of all in the world from fish farms. Can't take stricter laws? Move back to Norway and onto land with those subsidized licenses that are $9- to $12-million less than the auction price of an in-ocean fish farm.

See this post:

And you will find a half dozen posts on the Sandvik book it you check the list of posts of the past few months.And you may recall that last summer, algal blooms killed fish farm fish near Port Hardy. Hmm.

And see the June 17, 2016 post on the bloom and salmon die off in Clayoquot Sound: See:

This is Table 1 mentioned by Bethune:

A review of the impacts of salmonid farming on marine coastal ecosystems in the southeast Pacific

Taxonomic group
Algal species involved
Year of event
Approximate area affected
Alexandrium catenella
1972, 1981, 1989, 1991, 1994, 1995–2002
Toxic, source of PSP
Guzmán et al. (2002), Molinet et al. (2003)

Dinophysis acuta
1970, 1979, 1986, 1991, 1993, 1994
Toxic, source of DSP
Lembeye (1994), Suárez et al. (2003)

Prorocentrum micans
Fish mortality
Lembeye and Campodónico (1984)

Gymnodinium cf. clorophorum
1989, 2003, 2005
Loss of appetite in aquaculture fish
Iriarte et al. (2005)

Gymnodinium spp.
Benthic and pelagic resources mortality
Clément et al. (2001), Uribe and Ruiz (2001)

Avaria (1992)

Potentially harmful species present in Chile: Alexandrium ostenfeldii, Dinophysis acuminata, Dinophysis fortii, Dinophysis rotunda, Dinophysis tripos, Gonyaulax polyhedra, Gymnodinium catenatum, Gymnodinium splendens, Prorocentrum gracile, Ceratium tripos, Ceratium furca, Scrippsiella trochoidea, Noctiluca scintillans.

1993, 1997, 1999, 2000
27°S–30°S and 41°S–43°S
Toxic, source of ASP
Clément and Lembeye (1993), Suárez et al. (2003)

Leptocylindrus minimus
1989, 1993, 1998
Behaviour change and mortality in aquaculture
Clément (1994), Rojas (1998), Seguel (1999)

Chaetoceros convulutus
1991, 1995
Fish mortality
Rojas (1998)

Fish mortality
A. Clément (pers. comm.)

Potentially harmful species present in Chile: Skeletonema costatum

Rojas (1998), Seguel (1999)
Heterosigma akashivo
Salmonid mortality
Clément and Lembeye (1993), Rojas (1998)
Dictyocha speculum
Salmonid mortality
Rojas (1998)

  • Shellfish poisons: PSP, paralytic; DSP, diarrhoetic; ASP, amnesic.
  • † Species present in Chile recognized as harmful in other parts of the world. 

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