Woven Landscapes
Maayan Navon For Lofscapes
(1) Die off of Macha clams on the coast of Cucao, Chiloé © BBC Mundo<>  / (2) Salmon Mortality © Radio del Mar <>

The recent crisis in the Chiloé archipelago, a product of the phenomenon known as red tide, has triggered a series of speculations about its causes and effects. This week’s column will attempt to demystify some of the statements about the phenomenon in hopes of triggering reflection on our ignorance of territorial dynamics despite our enormous dependence on the natural resources we extract from our environment.

In January 2016, an unusual increase in the phenomenon known as red tide began to be observed in the Chiloé archipelago. This phenomenon severely affected the labor situation of the artisanal fishermen and especially those who harvest shellfish; these latter are a representative proportion of the area’s population. The phenomenon, also known as a harmful algae bloom (HAB), consists of an excessive increase of marine micro algae generating toxins that accumulate in mollusks, making them highly toxic when ingested by humans (1).

(1) University of Chile, “¿Qué es la Marea Roja?” (What is Red Tide?) Laboratorio de Toxinas Marinas(Laboratory of Marine Toxins) <>.

Although this is not the first time red tide has occurred in Chiloé, the explanation of the causes of this year’s outbreak have produced a state of public confusion as the phenomenon has been linked to two other consecutive events that occurred in unusual circumstances. First, at the end of February about 40,000 tons of fish died in different salmon farms located in the Reloncaví Sound. This generated suspicion and criticism towards the aquaculture industry, which when unable to get rid of such a huge amount of waste dumped about 4,500 tons directly into the sea. This generated the indignation of the entire population despite a report delivered by the Chilean Navy explaining the approved protocol under which such an action had been carried out (2). Weeks later (on April 25) a second event occurred in which there was a massive die off of macha clams along the entire Pacific coast of Chiloé. With no clear explanation of the phenomenon, the people of Chiloé linked this with the dumping of the dead fish, indicating that the dead salmon must have contained some type of harmful substance, given their massive die off and that there were no records of red tide killing macha clams in this way. At the same time, some claimed that the microalgae bloom had been caused by salmon waste and by the ecological impact of the salmon industry, which only contributed to further widespread distrust. In the absence of official clarifications regarding the phenomena affecting their source of livelihood, the population of Chiloé began to mobilize and created blockades at all points of access to the island, demanding greater economic support than initially offered by the government because closure of areas for harvesting would be prolonged for several more months.

(2) Armada de Chile,(Chilean Navy) “Informe Técnico Vertimientos”(Technical Report on Discharging of Substances) (May 6, 2016), Radio BioBio <>.

After almost a month of speculation, the Association of Marine Biologists of Chile issued a statement clarifying that the instance of HAB was the cause of death – probably by asphyxiation – of the salmon in the first place. The statement went on to say it is unlikely that the elimination of these at sea had some effect on the coastal ecosystems, due to the geographical and oceanographic characteristics of the site, which was evaluated and authorized for this purpose by the maritime authority (3). In regards to the die off of the macha clams, its cause was not exactly clarified, but it is presumed to be linked to other deaths that had occurred recently, such as those of the sardines in Queule, Cheuque, and Toltén in the previous three months, and that of the jibia (Chilean Humbolt Squid), that occurred on the Isla Santa Maria in January 2016. All of these phenomena are believed to be associated with the El Niño phenomenon, which has been classified as the most intense ever registered in the area (4), generating temperature increases in the water, which in addition to a very warm summer, could have become intolerable for certain species, while creating an optimum scenario for the microalgae that become red tide.

(3) Adolfo Velásquez, Presidente Biólogos Marinos Chile A.G., Comunicado Oficial (May 2016).
(4) Velásquez, Comunicado Oficial (Official Release) (May 2016).

Consequently, it has been established that neither the salmon waste nor the aquaculture industry was the cause of this episode of red tide. However, the impact that the salmon industry has on ecosystems cannot be ignored, as the amount of oxygen in the water does decrease as a result of waste deposited on the seabed. This is the reality that affects the entire south of Chile, including the known case that occurred in the fiords of Aysén, where the algae blooms were indeed caused by the salmon industry’s overexploitation. Furthermore, it is precisely the accumulation of these circumstances that generates the distrust from the local population who have viewed how salmon farming has taken hold in Chiloé, competing with artisanal fishing and with traditional small-scale activities.

Chile is a country that has more than 6,400 km of coastline, with a significant number of its population making a living directly or indirectly from its natural resources. Despite this dependence on our resources, we have not developed the capacity to understand the logic behind many of our ecosystems, which at times has led us to progressively degrade them. While some defenders of Chiloé have advocated the end of harvesting marine resources in order to stop such exploitation, culturally this proposal is not at all plausible. The challenge is to achieve a more integrated relationship with natural systems in which those engaged in harvesting have a basic understanding of their environment as a system. We must start by understanding the dynamics that affect us, which ones come from outside, which ones we have caused, and how we can influence them.

It is then about planning and managing both how we inhabit our environment and how we use our resources. We must understand that the natural systems are subject to a continuous transformation, not only due to their natural cycles but also to our role as shapers. In this way, we could begin to transcend a discussion on the issue that has until now been focused exclusively on the amount of the government support bonus and the extension or finalization of the blockades. Instead, we need to address the imperative creation of a research center for red tide, or studies that can identify and anticipate the phenomenon, and/or the investment needed to develop a plan for alternative activities so that the population does not depend solely on the harvesting of shellfish, especially considering that the phenomenon may reoccur in the immediate future (5).

(5) Velásquez, Interview CNN Chile, (May 6, 2016), <>.

Maayan Navon is a student in the Master’s Program in Landscape Architecture of the School of Architecture of the Pontifical Catholic University of Chile. Currently, she is working on her thesis on productive practices in the peat bogs of Chiloé.

(3) Dumping of salmon remains in the sea (April 28, 2016) © Facebook of CECPAN and Movimiento Defendamos Chiloé (We Defend Chiloé Movement)
(4) Blockades in Chiloé (May 5, 2016) © La Cuarta (newspaper) Tele13 <>
(5) Demonstrations in Chiloé (May 7, 2016) © Tele13 <>
(6) Areas affected by the red tide (May 4, 2016) © Resolución 600 de Seremi Saludde Los Lagos
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