La Jornada: Cave shrimp are essential for the nutritional balance of cenotes

The cenotes of Yucatan are home to cave shrimp of the genus Typhlatyaa key species in these underground aquatic ecosystems, due to its particular feeding mode. Fernando Álvarez Noguera, researcher at the UNAM Institute of Biology, shares with The Day the importance of this species for the nutritional balance of the cenotes.

These ecosystems, fundamental for the underground balance of the peninsula, face increasing threats from urbanization, pollution and deforestation.

Álvarez Noguera, who has studied these ecosystems for more than 10 years, explains that these crustaceans feed on the bacterial mats that form on the ceilings of the caves.

“Outside, rainforest plant matter falls to the ground, decomposes and seeps through the limestone. Inside the underground system, small amounts of methane are released, which are consumed by bacteria to generate energy and grow.”

He states that this process, called chemosynthesis, is the equivalent of photosynthesis in plants, which use light to transform inorganic compounds (carbon dioxide and water) into organic matter.

At this point, the shrimp Typhlatya They acquire great importance because, equipped with specialized scraping appendages, they reach the ceilings of the flooded caves to feed on the bacterial mats.

By converting microbial growth into animal biomass, shrimp become key to the balance of these ecosystems. “The entire food chain of the fauna that lives inside these caves takes off from them; if you remove them, it falls.”

To learn more about them, Álvarez Noguera worked with Brenda Durán, a graduate student in Biological Sciences, for two years. Together they analyzed a set of indicators for three of the four species present in the protected natural area of ​​Anillo de Cenotes and the Caribbean Cave Zone.

The findings revealed that the three species of Typhlatya They occupy different nutritional niches, which allows them to coexist without competing for resources. Typhlatya mitchelli It feeds on decaying vegetation and nitrifying bacteria in the shallowest sections. Typhlatya dzilamensiswhich lives near where fresh and salt water mix, takes advantage of the organic matter in the deeper sections. Meanwhile, Typhlatya pearsei consumes the bacterial biomass near the ceiling of the caves.

Cave shrimp, just a centimeter long and white in color, belong to an ancestral lineage that dates back about 250 million years. Its distribution extends from the coasts of the Caribbean and Mediterranean Sea to the Ascension Islands, Galapagos, Madagascar and Australia.

Due to the rapid urbanization of the Yucatan Peninsula, these crustaceans face an unprecedented threat. “Of course there must be development, but it cannot be done without limits. Sometimes we want to invent how conservation is done, but this means leaving things alone, there are not many recipes,” concludes Álvarez Noguera.