Les insectes qui habitent les lacs sont souvent des stades larvaires qui se métamorphosent et finissent par émerger en adultes volants. Sur terre, ils constituent une source vitale de nourriture pour de nombreux animaux terrestres vivant autour des lacs. Les poissons se nourrissent intensément de larves d’insectes, réduisant ainsi le nombre d’insectes qui parviennent à sortir de l’eau. Cela pourrait entraîner moins de nourriture pour les insectivores, tels que les araignées, les coléoptères prédateurs et les mille-pattes vivant autour de ces lacs.

Dans le cadre du projet Life RESQUE ALPYR, nous avons étudié 12 lacs de haute montagne dans les Alpes italiennes occidentales. Quatre lacs étaient sans poissons, quatre étaient en cours de retrait de poissons et quatre avaient encore des populations de poissons établies. Nous avons placé des pièges près du rivage des lacs et plus loin pour capturer des invertébrés terrestres, et nous avons également échantillonné des larves d’insectes pour évaluer la disponibilité des proies, c’est-à-dire les insectes émergents.

Qu’avons-nous découvert ?

Par rapport aux lacs contenant des poissons, les lacs sans poissons avaient beaucoup plus d’insectes aquatiques émergeant, ce qui confirme que les poissons réduisent une source importante de nourriture pour les animaux terrestres. Nous avons également trouvé plus de prédateurs terrestres près du rivage du lac, ce qui suggère leur préférence d’habitat et l’importance des insectes du lac comme source de nourriture.

Fait intéressant, nous n’avons pas observé de grandes différences dans le nombre de prédateurs terrestres entre les lacs avec et sans poissons. Cela suggère que bien que les insectes aquatiques jouent un rôle dans la formation des communautés terrestres voisines, d’autres facteurs peuvent également influencer l’abondance des prédateurs, et que davantage de lacs seront nécessaires dans de futures études pour obtenir une image claire de cette relation.

Bien que des recherches supplémentaires soient nécessaires pour comprendre pleinement l’impact des poissons introduits sur les prédateurs terrestres, notre étude met en lumière l’importante connexion entre le lac et les écosystèmes terrestres environnants. Les changements dans un environnement déclenchent souvent des réponses dans l’autre, et comprendre ces relations est essentiel pour concevoir des stratégies de conservation efficaces pour ces zones uniques de haute montagne.

Cette nouvelle découle du Projet de Master en Biologie (2025) de Gea Lukšić (Département de Biologie, Université de Lund), réalisé sous l’accompagnement et la supervision de Rocco Tiberti et Lucia Bello (Département de Biologie, d’Écologie et des Sciences de la Terre (DiBEST), Université de Calabre) ainsi que d’Anders Persson, Département de Biologie (Université de Lund).

The first video, titled “How to Eradicate Fish from High-Mountain Lakes,” presents the project’s main goals, focusing on the conservation and restoration of these lake ecosystems. High-mountain lakes are traditionally isolated from valley rivers by natural barriers that prevent the arrival of fish. However, many of these lakes now host fish species introduced through historical interventions, which have disrupted the natural ecological balance. These introduced species have become invasive, negatively affecting native fauna and the ecological quality of the habitat.

The video also highlights the collaboration with the FishME project, which uses a multidisciplinary approach to analyze the impact of fish and pollution, and to develop practical tools for managing and restoring mountain lakes.

In the second video, “Mountain Lake Rewilding Works!” Dr. Ventura explains how, after removing the introduced fish species, the original fauna of these lakes begins to recover. This rewilding has led to the return of native species, especially amphibians and macroinvertebrates, and has facilitated the recolonization of small mammals such as the Pyrenean desman, a rodent that relies on aquatic insects for food.

These videos emphasize the importance of conserving and restoring mountain ecosystems and demonstrate essential tools for effective, evidence-based management of these unique natural environments.

Our PhD student, Lucia Bello, from the University of Calabria, contributed with an oral presentation discussing the preliminary results of how introduced fish might have a negative impact on shrew populations living around alpine lakes.

Moreover, Dr. Ibor Sabas, post-doc researcher from the University of Innsbruck, presented a short talk on the results of a rapid eradication of introduced fish conducted on an alpine lake in Austria in collaboration between the Biodiversa FISHME project and LIFE RESQUE ALPYR project.

7^th European Congress of Conservation Biology

The European Congress of Conservation Biology (ECCB) is organized by the Europe Section of the Society for Conservation Biology (SCB) and aims to facilitate the exchange of conservation science and nature conservation practice and policy to promote the conservation of biological diversity in Europe; the theme of the 7^th edition was “Biodiversity positive by 2030”.

Despite the current challenges in conservation, the congress provided an interesting opportunity for researchers to share knowledge and collaborate, hoping to promote working together and taking action to make significant progresses in conserving our planet’s biodiversity.

You can find more on ECCB 2024 and have a look at the program of the congress at the official website (eccb2024.eu).

The scientific meeting was held in Tortosa and Vic on June 18 and 21, 2024. This time, the congress focused on promoting the study and conservation of native fish in the continental and marine aquatic ecosystems of the Iberian Peninsula.

The members of the LIFE RESQUE ALPYR project contributed knowledge obtained from their research in the field of conservation and restoration of high mountain lakes. They did so through presentations and the display of scientific posters.

For example, among other things, they presented work related to the use of genetic tools for the early detection of invasive fish species in lakes. Metabarcoding is an accurate tool for identifying and conducting phylogenetic analysis of species, allowing the detection of bioinvasions in their early stages.

The history of fish introductions in high mountain lakes was also narrated and explained in detail. This history was studied by researcher Marc Ventura along with Didier Galop and Olivier Baudier.

SIBIC congresses are held every two years to address scientific and management challenges related to various aspects of ichthyology. This edition, among other new topics, will include issues such as freshwater and marine fish, and conservation aquaculture.

In addition to being introduced species, they are considered invasive species, as they have a negative impact on the ecosystem.

Salmonids introduced in the Pyrenees include brown trout (Salmo trutta), rainbow trout (Oncorhynchus mykiss) and brook trout (Salvelinus fontinalis). The European minnow (Phoxinus sp.), a small Cyprinid, has also been introduced in many of the lakes in the Pyrenees, but in this case, the arrival is related with its use as live bait for fishing trout.

The species introduced in Mont Avic Natural Park are Arctic char (Salvelinus alpinus), the European minnow (Phoxinus spp.), the Italian riffle dace (Telestes muticellus), brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss); and the species introduced in Gran Paradiso National Park are brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta).

The proliferation of fish in these lakes has had negative consequences on the native fauna, has affected the structure and balance of the entire ecosystem and altered its trophic food web. Furthermore, the impact of introductions can also have consequences on terrestrial fauna populations such as birds, bats and small mammals such as the Pyrenean desman, which depend on aquatic insects as a food source.

The brochure can be consulted in digital format on the project’s website, but it can also be found at the tourist offices of the Alt Pirineu Natural Park and the Aigüestortes and Sant Maurici National Park in Catalonia, and the Mont Avic Natural Park and Gran Paradiso National Park in Italy.

Bats are distributed throughout most of the planet, except for the poles. They are found on continents as well as on islands far from the mainland. They can live from mountain ranges to desert oases, from tropical regions to boreal ones. They can take refuge in caves, tree hollows, rock crevices, buildings, or amidst the lushness of vegetation. Some even hide among the pebbles along riverbanks.

Unlike birds, bats fly with their hands while birds fly with their arms. They are the only flying mammals. The forelimbs of bats have evolved by elongating fingers and forearms. The bony structures we see in their wings are the fingers of the hand and support a thin, naked membrane called the patagium, which has muscular fibers and many blood vessels. The aerial life of bats has led to various flight-related adaptations. Like birds, bats have a highly developed pectoral musculature that allows them to move their wings and perform flapping flight. However, this musculature requires a rigid bony anchoring structure. This is the sternum, which is also quite developed and in many species has a keel-like shape. The size of bats varies greatly depending on the species.

Bats have other flight adaptations that, while not as evident as wings, are also important for flight. Most species only have one offspring, a characteristic that allows greater maneuverability for gestating females, thereby increasing the probability of survival.

The seasonal movements of bats can vary greatly from one species to another or even among populations of the same species. Some can make long seasonal migrations that in some cases exceed thousands of kilometers. This is the case of the lesser noctule bat (Nyctalus leisleri), very abundant in the forests of the Pyrenees.

In Catalonia, the most well-known migrations are those of the Schreiber’s bat (Miniopterus schreibersii), a species that flies relatively quickly and can make seasonal movements exceeding 300 km.

Another interesting aspect of bat biology is their longevity. It is longer compared to what would be expected based on their body size.

Bats exploit a wide range of food resources, from those that eat fruit to the mythical vampires. There are bats that eat frogs, birds, fish, small reptiles, scorpions, or even carrion. Another type of diet is nectarivorous, which corresponds to feeding on the nectar and pollen of flowers. Bats with this dietary regime contribute to pollinating a large number of plants.

There are even plant species whose pollination is highly specialized and depend on certain bat species. However, the majority of species (70%) of bats eat insects.

They have the ability to emit ultrasound for orientation, communication among themselves, and also for locating and hunting prey

The calls emitted for communication among bats, also known as social calls, are used between mother and offspring in breeding colonies, for mating, for marking territory, or for defense when they feel threatened. The process by which animals locate objects they cannot see or touch through the emission of acoustic signals and the analysis of their echoes is called echolocation. Ultrasound calls are produced by the vocal cords. The ultrasound emitted undergoes reflection when it encounters obstacles, and the echoes are captured again by the emitting bats. Echolocation allows measuring the distance between the emitter and the obstacle, but it also enables calculating the relative speed of the prey, since normally neither the bat nor the prey are stationary. Bats also use echolocation to receive information about the shape, size, and texture of the surface of the object in front of them.

Contrary to popular belief, bats are not blind. They have eyes that allow them, when there is sufficient light, to perceive the world in black and white.

Tracking 7 species of bats

One of the novelties of this new LIFE compared to the previous one is the study of some bat species. The studied bats are insectivores that feed on large quantities of insects and usually hunt around ponds.

The project includes tracking 7 species of bats: the Barbastelle bat (Barbastella barbastellus), the Greater mouse-eared bat (Myotis myotis), the Alpine long-eared bat (Plecotus macrobullaris) present in the Pyrenees and the Alps, and the Lesser horseshoe bat (Rhinolophus hipposideros), the Greater horseshoe bat (Myotis blythii), Bechstein’s bat (Myotis bachsteinii), and the Greater noctule bat (Nyctalus lasiopterus).

Technologies and tools for studying bats

The study of bats is complex and for this reason, it is the most unknown group of mammals that exists. They are difficult animals to observe because they hide in places that are inaccessible or not easily accessible and they fly at night, which makes their observation difficult. Some of the methodologies used to study them are:

• Bat captures
• Shelter boxes
• Shelter monitoring
• Listening stations with ultrasonic detectors
• Radio tracking

In the case of the LIFE project, the study of bats is carried out through the installation of ultrasonic recording devices emitted by bats and the installation of networks that allow specific identification of individuals, provide data on the biological cycle, and allow the collection of feces for analysis of their feeding and health status.

Thanks to ultrasonic recording devices, the activity of bats and the species that frequent ponds can be known. Their excrement allows us to know what they eat.

They have an important ecological role

Bats provide significant ecosystem services: they pollinate plants, act as seed dispersers, and help control insect populations – a bat can consume up to 3000 insects per night – making them natural pest controllers in agricultural and forest environments. They are major consumers of mosquitoes and therefore help us keep these insects, which are major disease vectors such as malaria or dengue, in check.

One of the interesting tasks of the project is to compare the presence of bats in ponds with fish and ponds without fish. When there are fish in a pond, the entire biodiversity of the pond is affected and modified. The study aims to determine if this mentioned impact on biodiversity also affects the structure of the bat community, that is, the abundance and diversity of bats.

Fonts:

• Serra-Cobo J, López-Roig M, Bayer X, Amengual-Pieras B i Guasch F. 2008. Els ratpenats: ciència i mite. Publicacions i Edicions de la Universitat de Barcelona.
• Serra-Cobo J, López-Roig i Bayer X. 2015. El tresor ecològic de les mines de Can Palomeres: els ratpenats. Publicacions de l’Ajuntament de Malgrat de Mar.
• Serra-Cobo J, Sanz V i Martínez-Rica JP. 1998. Migratory movements of Miniopterus schreibersii in the north-east of Spain. Acta Theriologica, 43(3): 271-283.
• https://secemu.org
• Guia de camp. Els ratpenats de Catalunya
• https://www.batmonitoring.org/v0/CAT/coneguem/coneguem.php

Lucia presented the effects of introduced fish on insectivore shrews, one of the topics of her PhD project titled “Cascading ecological effects of alien fish introduction and removal in high mountain lakes” (financed by the LIFE RESQUE ALPYR).

PhD Day at the University of Calabria

PhD Day at the University of Calabria was a day entirely dedicated to the University’s doctoral students who presented the research activities carried out, with the aim of raising awareness of the scientific value of the doctoral path and making people reflect on the benefits generated in society.

At the end of the day, the PhD Competition, an exciting “competition” divided into two sections: the Poster Competition in which the competitors illustrated the posters created specifically for their research topic, and the Pitch Competition, a presentation of a few minutes focused on the studies conducted. Rita Megale, a PhD student in Physical, Chemical, and Materials Sciences and Technologies, won the Pitch Competition. The Poster Competition for the Technical-Scientific Area was won by Lucia Bello, a PhD student in Life Science and Technology, while for the Socio-Economic and Humanistic Area, Aurelia Zucaro, a PhD student in Politics, Culture, and Development, was awarded.

The morning was opened by greetings from the Rector Nicola Leone, who underlined the increasingly important importance that research doctorates will assume in the training of the future ruling class.

You can find the prize-giving session of the day here.