These are environments that are very sensitive to changes. So any disturbance can alter its ecological state. If we bathe, we can leave residues (such as chemicals in creams), toxins and even viruses, bacteria or fungi. In addition, we remove sediment by fertilizing the pond and promoting the excessive proliferation of microalgae. All of this can affect the flora and fauna that inhabit these valuable ecosystems; among which are the seriously endangered amphibians.
High mountain ponds are unique and fragile ecosystems. Characteristics such as altitude, water chemistry or lake size mark the species that can live and can make them very unique. They are inhabited by organisms that live suspended in the water as part of the plankton (algae, water fleas, copepods…), through plants, mollusks, worms, insects and amphibians that live at the bottom or on the coast, to birds. and bats that feed on insects that come out of the water. The survival of mammals such as the endemic musk is also closely linked to the good ecological state of these habitats.
Furthermore, many high mountain lakes are located within Natural or National Parks, so they are specially protected and have specific regulations aimed at protecting the fauna and flora of these spaces, which are often seriously threatened. Among these rules is not bathing. Based on the evidence of the negative impacts of this action and the fact that there are no longer a few who reach these points, many people visit them and are tempted to soak.
Bathing seriously alters the balance of these ecosystems
When we get into a protected lake, we leave waste, toxins and even viruses, bacteria or fungi that can affect the fauna and flora that inhabit it. Many of the animals that live in them, such as amphibians, are especially sensitive. Through their skin they can capture chemical substances that are highly toxic to them, such as those contained in anti-mosquito creams or sprays. In addition, they are very sensitive to some bacteria, viruses and fungi that we carry. Just by putting our feet in the water we can release and harm species like the toad.
At the same time, when we put ourselves in the water, we remove the sediments from the bottom so that the pond is fertilized. As a consequence of the excessive availability of nutrients, too many microalgae grow and the oxygen in the water and its transparency decrease. This is what we call fertilization by human frequentation.
We also cannot let pets bathe. When dogs get into the water, they also stir up the bottom and release contaminants such as chemicals from anti-parasitic collars.
Scientific evidence to preserve these spaces of high ecological value
With the LIFE RESQUE ALPYR program (and its predecessors: the LimnoPirineus and the Bioaquae), coordinated by the CEAB-CSIC, we work on the preservation and restoration of high mountain ponds with actions of proven effectiveness such as the eradication of invasive species.
These actions have already allowed some of the lakes in the Eastern Pyrenees and the Alps where we work recovered the populations of amphibians, small mammals and other native species that had been disappearing due to the degradation of their habitats and that have now able to return when good ecological status was recovered.
The project also has an important aspect of environmental education and awareness, given that the complicity of citizens is essential to be able to recover and maintain in good condition these natural spaces that we all love so much. Actions in the area of awareness include, among others, talks and information material.
