Tourist activity threatens the beauty and biodiversity of Bacalar’s lake ecosystem

Bacalar Lagoon at Quintana Roo Mexico (Photo: Google, Trip Advisor)

The change in color at Mexico’s Lake Bacalar, known for its seven different shades of blue, is due to the accelerated growth of plankton, which has caused a deterioration in the life of the “microbialites,” a reef of bacterias that live in these waters: It has been recovering during the pandemic.

The 7-colors lake, as it is usually known, has this effect thanks to the different depths of its white sands. Nevertheless, factors such as the social establishment, feces, and urine from humans and animals, dumpsters, and the use of fertilizers has caused an opaque and greenish appearance to the water.

Luisa Falcón Álvarez, from the Institute of Ecology (IE) of the National Autonomous University of Mexico (UNAM), who has studied the phenomenon, regretted the loss of the splendor of this natural area located in Quintana Roo. “It is one of the planet’s treasures we have not taken care of; people are hurting the world’s largest freshwater bacterial reef,” she warned.

The scientist said that tourist activity in the área has risen in the last three years with a hotel occupancy of 85%, a situation that has damaged the wáter quality, as informed the UNAM in a release.

For over a decade, the researcher and a group of UNAM researchers have detected that Bacalar went from receiving tens of visitors every year to over 140,000 tourists.

This rise was caused by the apparition of sargassum in the Mexican Caribbean, which made travelers look for new spaces. One of the spots that became popular among tourists was Lake Bacalar, so hotels and tourism businesses were created without having any kind of regulation or proper conditions, which has harmed the water in the area.

However, the water is not the only characteristic affected at Lake Bacalar, for living microorganisms that live there have also been harmed for Bacalar is one of the largest water bodies of the Yucatán Peninsula since it is home to bacterial reefs, such as the case of microbialites, which have lived in the area for over 9,000 years and which are currently sick.

The UNAM researcher said that these places are extremely fragile, although the lockdown caused by the COVID-19 pandemic has allowed them to recover. Nevertheless, this will not be enough since this kind of community requires decades to regenerate completely.

Several places in Mexico have experienced a similar recovery during the COVID-19 lockdown. Several animal species, including jaguars, crocodiles, dolphins, giant manta rays, flamingos, herons, pheasants, coyotes, bears, and whales, have been able to return to their natural habitats and have been spotted throughout the country. Moreover, bioluminescence has been registered at different beaches and popular tourist places like Acapulco have witnessed how the water has acquired turquoise colors that had not been seen in several years.

Falcón Álvarez explained that “the problem worsens because this lake is part of the hydrological basin that constitutes a cross-sectional coastal corridor of surface and underground water flow that connects the Caribbean with other water bodies, and now, there are great amounts of nitrogen and phosphorous that promote the growth of plankton, which has stemmed in the change in color.”

The expert mentioned that the economic processes related to tourism and social matters are not against the conservation of the environment, moreover, people must be aware of the advantages brought by the ecosystems, such as Walter filtering, oxygen production, biodiversity, and carbon capture.

She said that if the environment gets sick, people will be in contact with an unmeasurable amount of viruses and bacteria, most of which are harmless, “but some will not be and an example of that is the SARS-CoV-2 pandemic that is linked to the illegal trafficking of wild fauna. We must learn that we are not apart from the health in communities and ecosystems and that the best vaccine is the conservation and sustainable development.”