The International Conference on the Conservation of High Mountain Lakes and Mires & 2nd International Meeting on the Conservation of High Mountain Lakes will take place in Vielha (Val d’Aran, Catalan Pyrenees) on 28, 29 and 30 October.

The conference will bring together specialists, primarily from the scientific and technical sectors, working on the conservation and ecological restoration of high mountain lakes, ponds, streams, peatlands, mires and other aquatic ecosystems. These environments are increasingly affected by pressures arising from climate change, hydrological alterations, land-use changes and the introduction of invasive species.

The aim of the event is to share the latest advances in this field. These include those linked to the LIFE RESQUE ALPYR project (2022–2026), through which a range of ecological restoration actions have been carried out across four Natura 2000 sites in the Pyrenees and the Alps. Key actions include the removal of introduced fish from mountain lakes, the functional restoration of peatlands and wet meadows, improvements to grazing management in these ecosystems, and the recovery of particularly sensitive species such as amphibians, mammals and aquatic invertebrates. In addition to presenting the outcomes achieved, including biodiversity recovery results, participants will share protocols and methodologies that could be applied in other regions of the world.

A program with international experts

The invited speakers include Roland Knapp (University of California), a world-leading expert in high mountain lake restoration and amphibian conservation; Helge Bardal (Norwegian Veterinary Institute), a specialist in the eradication of invasive species in freshwater ecosystems; Borja Jiménez-Alfaro (University of Oviedo), a leading researcher in plant biodiversity and mountain mire ecology; as well as researchers Lucia Bello and Rocco Tiberti (University of Calabria), specialists in the conservation of high mountain lakes and directly involved in the LIFE RESQUE ALPYR project. The program also includes contributions from representatives of the project partners and the protected areas where the restoration actions have been implemented.

The conference scientific committee comprises Teresa Buchaca and Marc Ventura (CEAB-CSIC), Rocco Tiberti (University of Calabria), Aaron Pérez-Haase (University of Barcelona) and Quim Pou-Rovira (Sorelló). They are responsible for ensuring the scientific quality of a program that will bring together some of the leading international specialists in the field.

The third and final day of the event will be devoted to a field visit to Muntanyó d’Àrreu Lake and the Clots de Rialba mires, two of the sites where LIFE RESQUE ALPYR has delivered ecological restoration actions. The excursion will allow participants to observe first-hand the results of the interventions carried out and to exchange experiences on the management and conservation challenges facing some of Europe’s most unique and vulnerable mountain ecosystems.

Further information and the full program are available via this link.

Restoring Unique Ecosystems in the Pyrenees and the Alps

High mountain aquatic and semi-aquatic ecosystems, including lakes, ponds, streams, peatlands and mires, support highly specialised biodiversity adapted to extreme environmental conditions. Despite their exceptional ecological value, they are among the habitats most vulnerable to the impacts of climate change and other human-induced pressures.

These environments provide essential ecosystem services, including water and carbon storage, hydrological regulation, and the conservation of numerous rare or threatened species. Their protection is therefore considered a priority at the European level.

In this context, the LIFE RESQUE ALPYR project has contributed to generating scientific knowledge and management tools that can support the restoration and conservation of these ecosystems in other mountain areas across the Pyrenees, the Alps and elsewhere in Europe.

• Ten months after the eradication programme, both lakes show a remarkable recovery in water transparency and biodiversity, including the return of amphibians and aquatic invertebrates, groups that had not been recorded since monitoring programmes first began in 2014

• The initiative, carried out within the framework of the European LIFE RESQUE ALPYR project, provides new evidence on the use of rotenone as a tool for ecological restoration

The first observations carried out following the intervention at the lakes of Tres Estanys del Mig and Tres Estanys de Baix, in Alt Pirineu Natural Park, confirm the complete eradication of minnows (Phoxinus spp.) and provide evidence of the first signs of ecological recovery. The presence of this fish in the Catalan Pyrenees is the result of its accidental introduction as live bait for recreational trout fishing, a practice that has caused significant alterations to these high-mountain ecosystems.

The intervention, carried out last September within the framework of the European LIFE RESQUE ALPYR project, involved the application of rotenone, a biodegradable piscicide, with the aim of restoring the ecological balance of these lake ecosystems and generating scientific evidence on the effectiveness and safety of this restoration methodology. This is the second pilot trial undertaken in lakes of the Catalan Pyrenees, following the intervention conducted in September 2024 in Lake Manhèra, in the Val d’Aran.

Data collected to date confirm that the intervention achieved its main objective, namely the eradication of minnows from both treated lakes. At the same time, the first monitoring results show clear signs of ecological recovery, including a marked improvement in water transparency and the return of amphibians and aquatic invertebrates, groups that are particularly sensitive to the impacts caused by this introduced species.

According to Barend L. van Drooge, researcher at the Institute of Environmental Assessment and Water Research (IDAEA-CSIC), “Monitoring of rotenone levels in the water has confirmed that it degrades at the rate originally predicted, with a half-life of between 10 and 20 days. This reduces its persistence in the aquatic environment and suggests a very limited impact on the ecosystem.”

Furthermore, no traces of rotenone have been detected in the river located downstream of the treated lakes. This result confirms that, as anticipated, the product remained confined to the treatment area and did not disperse beyond the lakes targeted by the intervention.

Restoring altered ecosystems

Fish introductions are one of the main causes of biodiversity loss in high-mountain lakes. Minnows are a species that has become established in numerous Pyrenean lakes as a result of their accidental introduction as live bait for recreational trout fishing. Their high reproductive capacity and adaptability favour their spread and cause significant disruptions to aquatic food webs.

The presence of this fish leads to a substantial decline in biodiversity, particularly among small aquatic organisms and amphibian populations, as it preys on amphibian eggs and alters the conditions required for successful reproduction. For this reason, its eradication is considered one of the most effective measures for promoting the recovery of high-mountain lake ecosystems.

Surveys conducted ten months after treatment revealed a highly positive response, with a notable recovery in both water transparency and biodiversity. The return of amphibians and aquatic invertebrates has also been recorded. These groups had not been detected since the first monitoring programmes began in 2014.

A benchmark experience for the conservation of Pyrenean lakes

The intervention at Tres Estanys represents the second pilot trial developed within the LIFE RESQUE ALPYR project, following the experience at Lake Manhèra in the Val d’Aran. In both cases, minnows were successfully eradicated and the first signs of recovery of the characteristic biodiversity of high-mountain lakes have been observed.

According to Quim Pou-Rovira, Director of Sorelló Estudis al Medi Aquàtic and Technical Lead of the intervention, “In the case of Tres Estanys, the challenge was particularly significant because the intervention was carried out in a larger and more complex system than Lake Manhèra, given that it involved interconnected lakes.” The results obtained demonstrate that this methodology can also be effective in larger and more complex lake systems.

An important difference between the two lakes treated in Alt Pirineu is that previous minnow control measures had already been carried out at Tres Estanys del Mig using mechanical methods such as nets, traps and electrofishing. Although these actions did not completely eradicate the species, they succeeded in keeping the population under control for several years.

According to Marc Ventura, researcher at the Centre for Advanced Studies of Blanes (CEAB-CSIC) and coordinator of the LIFE RESQUE ALPYR project, “The initial data indicate that ecological recovery is progressing more rapidly in Tres Estanys del Mig than in Tres Estanys de Baix and Lake Manhèra. One possible explanation is that previous efforts to control minnow populations helped preserve a latent reservoir of species within the sediments, which may now be facilitating a faster recolonisation of the ecosystem.”

Long-term scientific monitoring

Although the eradication of minnows has already been confirmed in both pilot trials, the project partners stress that the full recovery of these ecosystems is a gradual process requiring long-term monitoring. For this reason, monitoring activities will continue over the coming years in order to assess changes in biological communities and document the recovery of the lakes’ natural ecological processes.

According to Marc Garriga, Director of Alt Pirineu Natural Park, “These initial results are very encouraging for the conservation of high-mountain lakes. Beyond the success of the intervention itself, the pilot trial demonstrates that it is possible to restore ecosystems that had lost a significant part of their biodiversity and to generate valuable knowledge for addressing similar challenges in other Pyrenean lakes.”

The intervention was coordinated and implemented by Sorelló Estudis al Medi Aquàtic, S.L. and the La Sorellona Association, under the scientific supervision of the Centre for Advanced Studies of Blanes (CEAB-CSIC) and the Institute of Environmental Assessment and Water Research (IDAEA-CSIC), with the direct support of Alt Pirineu Natural Park and Forestal Catalana.

The LIFE RESQUE ALPYR International Conference will take place from 28 to 30 October 2026 in Vielha – Pyrenees, bringing together researchers, conservation practitioners, protected area managers and technical professionals working on high mountain aquatic ecosystems and mires.

Conceived as a scientific and technical meeting with an international scope, the conference will focus on ecological research, restoration experiences, methodological advances and cross-site knowledge exchange related to high mountain ecosystems across Europe.

Main thematic areas

The scientific programme will be structured around three thematic sessions:

• High Mountain Lakes Conservation: ecology, impacts and restoration
• Mires and Wet Meadows: hydrology, vegetation and biodiversity restoration
• Cross-ecosystem Linkages: lessons learned, management approaches and transferability

Researchers and practitioners are invited to submit abstracts for oral presentations or posters related to these themes, as well as other research or management experiences connected to high mountain ecosystems.

Important dates

• Abstract submission deadline: 15 August 2026
• Notification of acceptance: September 2026
• Final programme publication: early October 2026
• Conference dates: 28–30 October 2026

For questions regarding abstract submission, registration or conference logistics, please contact the LIFE RESQUE ALPYR Conference Organising Committee at: liferesquealpyr@ceab.csic.es

Further updates and practical information will be published on the conference website.

The LIFE RESQUE ALPYR International Conference will provide a platform to share knowledge, strengthen collaboration and advance conservation and restoration strategies for high mountain ecosystems across Europe.

The pilot test, which will start this week, aims to eliminate introduced species and restore the ecological balance of these high-mountain ecosystems. The trial will involve the use of rotenone, a biodegradable ichthyocide. The results of the action will provide essential data to evaluate the effectiveness and safety of this product, contributing to the development of safe protocols for the application of piscicides to mitigate the impact of introduced species, such as minnows, in high mountain lakes.

The initiative is part of a broader strategy to restore high-mountain aquatic habitats within the framework of the LIFE RESQUE ALPYR project, with the aim of converting the restored lakes into biodiversity reserves and ecological corridors.

The environmental impact of minnows in high mountain lakes

One of the main threats to high mountain lakes is the presence of introduced fish, which reduce the biodiversity of native species and disrupt the balance of the ecosystem.

Among the introduced fish species, minnows (Phoxinus spp.) have the greatest ecological impact and also pose the greatest challenge for demographic control. It is a small cyprinid with rapid growth and a high reproductive rate, highly adaptable and capable of forming dense populations.

Conventional capture techniques used to remove fish from high-mountain lakes do not always yield satisfactory results when minnows are present. For this reason, it is necessary to explore alternative methods.

A Pioneering Initiative

Rotenone is a natural, biodegradable ichthyocide extracted from various tropical and subtropical plant species of the legume family. These plants, along with others with toxic properties such as those of the genus Verbascum, have traditionally been used for fishing in rivers and lakes around the world, depending on the plant species available, including in the Pyrenees.

In the environment, rotenone degrades rapidly, persisting for only a few days or weeks. To date, its use as an ichthyocide has been primarily applied in North America, Australia, New Zealand, the United Kingdom, and northern Europe—especially Norway—with some isolated experiences in the rest of Europe, including Spain.

The LIFE RESQUE ALPYR features two pilot trials using rotenone, pioneering actions in the context of high-mountain lakes in Europe.

The first of these trials took place in 2024 at Lake Manhèra (Val d’Aran). This is the only precedent so far for the application of rotenone in a high-mountain lake in Europe. The intervention was successful, as the minnows were eradicated and the lake is currently recovering its biodiversity, with the recolonisation of amphibians and various invertebrates, such as certain dragonflies, which had disappeared due to the introduction of the minnow.

In the Tres Estanys area, two applications are planned: the first at Lake Tres Estanys del Mig, scheduled between September 2 and 4, and a few weeks later at Tres Estanys de Baix. The goal is to restore the ecological integrity of these sites and to increase knowledge about the use of rotenone in a more complex scenario, acting on two lakes whose combined volume is three times that of Lake Manhèra.

The intervention will be carried out by Sorelló, Estudis al Medi Aquàtic, S.L. and Associació La Sorellona, under the scientific coordination and supervision of the Centre for Advanced Studies of Blanes (CEAB-CSIC) and the Institute of Environmental Diagnosis and Water Studies (IDAEA-CSIC), with the direct support of the Alt Pirineu Natural Park and Forestal Catalana. The entire process will be monitored with visits from specialists from Norway, a leading country in this type of application, and through a rigorous monitoring program to ensure the safety and effectiveness of this innovative technique.

Giorgia Mattioli, from the University of Pavia, presented a poster illustrating the eradication dynamics of alien fish from 15 lakes in the Italian Alps, four already eradicated by the LIFE BIOAQUAE project and the remaining eleven addressed by the current LIFE RESQUE ALPYR project. Thanks to the combination of various mechanical methods (fyke nets, gillnets, rod-angling, and electrofishing), which preserve the lakes’ native fauna, the population density of introduced fish can be reduced until they are completely eradicated. Taking into account the complexity and uniqueness of each individual lake, these data can serve as a guide for future ecological restoration actions in high‑altitude lakes under similar conditions.

Lucia Bello, from the University of Calabria, contributed with an oral presentation on the cross‑ecosystem effects induced by alien fish on various insectivore groups associated with high‑altitude lakes. These lakes can serve as important prey sources for a variety of semi‑aquatic and terrestrial insectivore predators present in these ecosystems, ranging from ground‑dwelling invertebrates (such as spiders and beetles), to birds (dipper and other passerines) and mammals (shrews and bats). Since insectivores and introduced fish compete for a shared food resource (aquatic macroinvertebrates in their larval and/or adult stages), our research seeks to determine whether the presence of fish in these lakes can negatively affect the insectivore community.

The Conservation Biology Conference for Early Career Researchers

The Conservation Biology Conference for Early Career Researchers (ECR) is organized by the Society for Conservation Biology Italy Chapter APS (SCB Italy) and represents a key opportunity for young researchers at the start of their careers. It offers a stimulating environment in which they can present their work and network with peers and established scholars in the field. The theme of the second ECR conference in 2025, held in L’Aquila, was “Biodiversity and Global Change: a Conservation Perspective.”

You can find more information and the full conference program on the official SCB Italy website.

On 6 May, the Pyrenean Institute of Ecology (IPE-CSIC) in Jaca (Aragón) hosted a new session of the Itinerarios Cicerón, an initiative launched by the Spanish National Research Council (CSIC) to bridge scientific knowledge with society and to promote evidence-based decision-making. This edition focused on biodiversity recovery and science-based actions for nature restoration.

Teresa Buchaca, researcher at the Centre for Advanced Studies of Blanes (CEAB-CSIC), contributed as an expert in high mountain aquatic ecosystems, which are central to the LIFE RESQUE ALPYR project. In her talk, she explained that high mountain lakes function as true natural laboratories, as they allow researchers to track human impacts over time through palaeoecological analysis. This historical perspective is key to understanding ecosystem changes and planning more effective restoration measures.

As a successful example, Buchaca presented LIFE RESQUE ALPYR, a project aimed at restoring the ecological functionality of mountain lakes in the Pyrenees. She outlined actions such as removal of invasive species and the restoration of natural cycles, which have shown proven effectiveness and are based on the scientific knowledge generated at CEAB-CSIC and by the project’s partner institutions.

The event also featured CEAB researchers Jordi Pagès and Daniel Oro, who shared their insights on the restoration of coastal and delta ecosystems. In addition, pre-recorded videos were shown, offering a glimpse into the researchers’ work in the lab and in the field.

The session brought together scientists from various CSIC centres, nature reserve managers, public authorities, civil society organisations, businesses, and journalists. Coordinated by Graciela Gil-Romera (IPE-CSIC) and Óscar Godoy (EBD-CSIC), the organisers emphasised that nature restoration is an ecological imperative, and can only be successful if grounded in robust and applicable scientific knowledge.

The Itinerarios Cicerón initiative aims to connect research teams working on similar topics and to translate their findings into practical knowledge for society, helping to effectively address today’s environmental challenges.

More information is available at this link.

But how does Catalonia face this challenge? During this conference, we explored the implications and challenges of implementing this law in our territory. Many questions arise: How will environmental policies be modified to meet European requirements? How will restoration initiatives align with local socioeconomic needs? Which projects are already driving the recovery of our ecosystems?

To address this topic, the conference featured experts in conservation and restoration of different ecosystems. Among them was researcher and coordinator of the LIFE RESQUE ALPYR project, Marc Ventura.

The researcher began his presentation by stating that high mountain aquatic ecosystems are the most threatened, having suffered the greatest loss of biodiversity compared to other biomes.

He then spoke about the conservation and restoration of high mountain aquatic ecosystems in the Pyrenees, specifically high mountain lakes, with actions such as, among others, the removal of introduced fish species.

For instance, in a lake with trout, amphibians begin to disappear, and there is significant disruption to the trophic network in the littoral zone, where fish consume the largest macroinvertebrates. Negative effects increase when, in addition to trout, the presence of minnow—a small cyprinid introduced in many Pyrenean lakes as live bait for trout fishing—is detected.

The actions of LIFE RESQUE ALPYR have allowed the recovery of native animals that had disappeared from these spaces, such as the red frog, the Pyrenean newt, the midwife toad, various bat species, and the desman. At the same time, they are restoring the overall ecological health of these ecosystems, which, despite being in isolated areas, are heavily impacted by human activities.

Annual Prismàtic Conference

The event featured, among others, the Secretary for Ecological Transition of the Department of Territory of the Government of Catalonia, the Director General of Environmental Policies and Natural Environment of the Government of Catalonia, and the Deputy Director General of the Ministry for the Ecological Transition. From a research perspective, participants included researchers from the Centre for Ecological Research and Forestry Applications (CREAF), the Centre for Advanced Studies of Blanes (CEAB-CSIC), the Institute of Marine Sciences (ICM-CSIC), the Autonomous University of Barcelona (UAB), and the University of Barcelona (UB).

The event was held at the Administrative District of the Government of Catalonia in Barcelona. It is an initiative of the Department of Climate Action of the Government of Catalonia, coordinated by the Centre for Ecological Research and Forestry Applications (CREAF).

You can watch the full conference at this link.

Researchers from the LIFE RESQUE ALPYR project will share the scientific knowledge gained from the research project carried out in the area.

This time, projects will be presented that shed new light on research lines initiated three years ago, helping to understand the complexity of a place like the National Park. The conference will also cover the continuation of projects started more than three years ago, which have given rise to new lines of research, many aimed at mitigating climate change.

The talks will be complemented by a series of interventions during a field trip to the Park itself to make the presentations more engaging.

It will be an opportunity to promote collaboration between different sectors to conserve the ecosystems of the Pyrenees.

The conference will feature over 30 speakers, including representatives from the LIFE RESQUE ALPYR project, coordinated by the Center for Advanced Studies of Blanes (CEAB-CSIC).

Researchers from the project will give four presentations related to the project’s results.

The first two will take place on October 16, starting at 11 a.m. The first presentation, by Teresa Buchaca, will address the impact of fish removal on the biomass and composition of phytoplankton in five lakes in the Park. This will be followed by a presentation by Víctor Osorio on the recovery of macroinvertebrates after the eradication of invasive fish species.

The third presentation, by Laia Nogué, will be on October 17, starting at 4 p.m., and will focus on the impact of hydraulic regulation on the populations of the Pyrenean desman in the Catalan Pyrenees.

And finally, the last presentation will be by Maria Àngels Puig on October 18th. She will talk about the importance of hidden biodiversity in the rivers of the Aigüestortes i Estany de Sant Maurici National Park.

The conference program includes a total of 25 presentations and 7 on-site presentations during a half-day field trip to the Sant Nicolau Valley towards Estany Llong.

The conference is open to the interested public until the presentation room reaches full capacity. More information about the XIII Research Conference on the Aigüestortes and Estany de Sant Maurici National Park is available at this link.

High mountain lakes, natural ecosystems that originally did not contain fish, have undergone drastic changes due to the introduction of non-native species, primarily trout and minnow. This introduction has caused significant predation of the native fauna, profoundly altering the ecological balance of these lakes.

The study that Dr. Ventura presents analyzes the impact of these introductions on cladocerans, such as Daphnia, in the high mountain lakes of the Alps and the Pyrenees. The results indicate that lakes with minnow have suffered a more severe impact on Daphnia populations.

As part of the conservation projects – LIFE BIOAQUAE, LIFE LIMNOPIRINEUS, and LIFE RESQUE ALPYR – both trout and minnow have been eliminated or are being eliminated from 32 high mountain lakes in the Catalan Pyrenees and the Italian Alps.

Preliminary evaluations show that Daphnia populations have recovered in most lakes where they were previously absent. Additionally, the eradication of minnow has been accompanied by an increase in species richness, as well as the appearance of planktonic species and those associated with macrophytes.

Throughout the congress, there will be a total of 65 oral presentations and 41 posters, as well as two keynote lectures. The contributions will cover a wide range of topics related to the biology of cladocerans, including our beloved Daphnia, as model organisms. Topics such as ecology, evolutionary biology, genomics, interaction with environmental stress factors, diversity, biogeography, and systematics will be addressed.

The conference will feature over 60 speakers, including a significant representation of scientists from the LIFE RESQUE ALPYR project, coordinated by the Center for Advanced Studies of Blanes (CEAB-CSIC).

This event brings together scientists, managers, and local entities with the goal of disseminating the scientific knowledge gained from the research conducted in the area, while also providing insights into how this knowledge can be applied to the management of natural spaces.

It will be a space to foster collaboration among different sectors to conserve the Pyrenean ecosystems.

The project’s researchers will give three presentations related to the project’s results (and the results of preceding projects).

The three presentations will take place on September 4th, starting at 3:00 PM in the multipurpose room of MónNatura. These will be part of the session dedicated to ponds, moderated by Núria Catalán, another researcher from CEAB-CSIC. The first presentation, by Danilo Buñay, will discuss primary production as the main determinant of transparency in ponds. Next, Marc Ventura, coordinator of the LIFE RESQUE ALPYR project, will talk about littoral crustaceans in ponds and their relationship with fish presence. Finally, Víctor Osorio will present on the recovery of macroinvertebrates after the eradication of invasive fish species.

The other two presentations will take place on September 5th from 5:00 PM in the session dedicated to rivers and wetlands, moderated by the researcher of the project and of the University of Barcelona, ​​Josep M. Ninot. The first presentation will be that of Eulàlia Pladevall, on the vegetation of the wetlands after five years of livestock exclusion. Then, Josep M. Ninot, will talk about the distribution of organic carbon in the soil in four Pyrenean wetlands.

The conference program includes a total of 76 participations (66 presentations, 10 in poster format) spread across 10 thematic sessions: landscape evolution, archaeology, geology, cultural heritage, ponds, monitoring networks/snow science, socio-ecological systems, animal ecology and biodiversity, forest ecology and biodiversity, and rivers and peatlands. There will also be a poster session covering various topics.

More information about the III Research Conference of the Alt Pirineu Natural Park can be found at this link.