Thousands of dead fish washed away in the Spanish lagoon


Spanish authorities have expanded the ban on harmful fertilizers around the saltwater lagoon on the Mediterranean coast of a country where tons of dead fish have been washed away in recent weeks.

In Murcia’s Marmenor, on the Mediterranean coast of southeastern Spain, once a tourist attraction and sanctuary for marine life, fish stocks have plummeted in recent years, with similar mass mortality in 2016 and 2019. increase.

Residents began seeing dead fish and crustaceans on August 16th.

“We estimate that about 20 tons have died so far,” said José Luis Garcia, head of the World Wildlife Fund’s marine program in Spain two weeks ago.

The beach was closed for two weeks while cleanup work was underway to remove carcasses of fish.

Murcia is one of Spain’s leading producers of fruits and vegetables, many of which are exported to Northern Europe.

The Murcia government estimates that fertilizer spills from nearby farms of about 5 metric tonnes (5.5 tonnes) are flowing into the lagoon daily.

Locals found hundreds of dead fish washed up on the shore on August 16.

Spanish pollution
On August 25, 2021, a city official walks near a man with a banner that says “The politician who killed the Marmener Lagoon” in Puerto Verodela Manga near Murcia, Spain. (JoseMiguel Fernandez / AFP via Getty Images)

The Murcia government estimates that fertilizer spills from nearby farms of about 5 metric tonnes (5.5 tonnes) are flowing into the lagoon daily. Jorge Sanchez, a biologist at the Ecological Society Asociación de Naturalistas del Sureste, explained that some of these fertilizers can cause algae outbreaks, depleting oxygen in surface waters and killing fish.

“Various scientific and regional reports have episodes of anoxia, oxygen deficiency, which was caused by the large arrival of nutrients in the lagoon, which promotes overdevelopment of algae. Algae that stop photosynthesis and start consuming oxygen in the middle of the night consume oxygen from the deep lagoon, which kills the fish, “Sanchez said.

A group of locals involved has set up a campaign group, SOS Marmener, to pressure local governments to do more to protect the lagoon.

Isabel Rubio of SOS Mar Menor Spokesperson said he would like to hold the farm responsible for nitrate contamination.

“What we want is to focus on all the farms surrounding this Marmener, mainly including intensive irrigation, which contributes to this pollution by nitrates,” Rubio said. rice field. “We want the measures to be located where the farms are, not here. That is, irrigation and cultivation should be banned on farms that use water illegally. there is.”

Local farmers believe that the problem is not in their irrigation, but in the underground aquifers.

Manuel Martinez of Orange Farmer, Chairman of the Farmers Community in Cartagena, said local agriculture uses an accurate irrigation method called the “drop-by-drop system” to avoid wasting water.

“99% of our area is localized irrigation, which is a precision risk. What is being developed here is precision agriculture, everything is managed. This applies to each crop. It measures the amount of water that is applied, when it is applied, and when it is applied. It is applied and absolutely everything is analyzed before planting a garden plantation and you can see what makes up for it. Absolutely everything is controlled. ” Mr. says.

Scientists at the Murcia Marine Center are analyzing the causes of fish kills.

They confirmed that the cause was “hypoxia” (low oxygen levels) due to the outflow of agricultural fertilizers.

Researchers believe that the system collapsed after decades of irrigated agriculture.

Victor Manuel Leon, a marine pollution expert at the Spanish Institute of Oceanography in Murcia, said there are also problems with improperly treated wastewater and intensive farming.

“This has accumulated over the last few decades, both due to improperly treated wastewater emissions, the development of intensive agriculture over the last 30 or 40 years, and the lack of control of these emissions from these activities. As a result of the activity, this has brought large amounts of nutrients, especially nitrogen and phosphorus, to the system, which has been assimilated over the years, but the time has come for the system to fail, “says Leon. ..

The Murcia local government announced on August 25 that it would ban the use of inorganic nitrogen fertilizers on farms within 1,500 meters (1,640 yards) of the Mar Menor lagoon.

The lagoon is a famous beauty spot and is popular with tourists.

Reuters contributed to this report.

Associated Press