The environmental problems surrounding the Mar Menor have now led to a political blame game after more than five tonnes of dead fish have been washed up on its shores.

The cause is said to be due to lack of oxygen, or apoxia, a regular issue in the lagoon in recent years, but exactly what causes the problem seems to be a bone of contention, now leading to a blame game between the regional and national governments.

The Murcian administration has called on Madrid to invest in a proposed plan for the creation of a collector plant that would remove the nitrates in the run-off waters resulting from farming activity in the areas surrounding Europe’s largest saltwater lagoon. The central government, in the form of Teresa Ribera, the Minister of Ecological Transition, countered that such a measure would only be ‘whitewashing’ the problem rather than fixing it. For her, the cause of the environmental disaster are the illegal farming practices that are carried out in abundance, including, she says, desalination plants

Once a magnet for tourists, today the Mar Menor is something akin to ‘green soup’ with environmental activists, residents and tourists less than impressed with the political back dealings and apathy, given that the degradation of the lagoon has been taking place since biological mass die-offs were recorded back in 2016 and 2019.

The water apoxia in the saltwater lake is caused by nitrates and phosphates coming in through the Rambla del Albujón stream, just to the south of Los Alcazares, which empties the fresh water from an aquifer, a body of rock that collects excessive rainwater. Those chemical nutrients are ingredients used in farming fertilizers and their accumulation helps the overgrowth of phytoplankton or micro algae

Rambla del Albujón stream just south of Los Alcazares

The green layer of the phytoplankton biomass stops the sunlight from reaching the bottom of the lake and also consumes the oxygen in the water, in essence suffocating the fish and crustaceans living underneath it. Additionally, the summer months, with their lack of wind and lower levels of water, contribute to the exacerbation of the problem.

“We know what to do and we want to get on and do it, we just need permission from central government to get on with it,” exclaimed Fernando López Miras, the President of Murcia, revealing his sense of frustration.

For the time being, however, the regional government has started cleaning one of the gullies that connects Mar Menor to the Mediterranean Sea in an effort to further oxygenate the water body, although the Ecological Ministry had said that this would likely not be an particularly efficient solution.