One of the longest dispersal movements carried out by a wolf registered

Cooperation between Germany, France and Catalonia has made it possible to document in Europe one of the longest dispersal movements ever made in the world by a wolf (Canis lupus), thanks to the monitoring of the species in the field and also to the collaboration between genetic laboratories in the three territories.

Specifically, wolf tracking by molecular genetics implemented in Germany, France and Catalonia, as well as a scientific collaboration between three laboratories, including the Veterinary Service of Molecular Genetics of the Universitat Autònoma de Barcelona, has made it possible to discover that an individual wolf traveled 1,240 km between the place of its birth near Nordhorn, Germany, in 2020 until reaching the municipality of Vilaller (Alta Ribagorça, Lleida), where it was last detected in February 2023, passing through France in May 2022.

This is the largest gray wolf dispersal event ever documented worldwide. Previously, the longest straight-line distances on record involved 1,092 km between Norway and Finland (Wabakken et al., 2007), 880 km between Germany and Belarus in 2009 (Reinhardt und Kluth, 2016), and 829 km between Switzerland and Slovakia in 2022-2023 (KORA).

The discovery of the wolf's travels is the result of locating wolf feces one year ago by the Rural Agents' Special Canine Group (GEK9), under the framework of the wolf monitoring programme being carried out and coordinated by agent Gabriel Lampreave, together with the Catalan Ministry for Climate Action, Food and Rural Agenda.

Specifically, wolf feces were detected on 13 February 2023 in Alta Ribagorça thanks to the use of specially trained dogs from the Special Canine Group (GEK9) to identify large carnivore feces.

In this area there is a male identified since 2021, but the automatic photographs taken during the winter of 2022-2023 provided elements that led to suspect of the presence of a possible second specimen. For this reason, prospection efforts were increased, which allowed to collect a sample on the southern slope of the Pyrenees, in the municipality of Vilaller. The genetic analysis carried out by the laboratory of the Universitat Autònoma de Barcelona (UAB) indicated a "w1" lineage referring to the wolf population of Central and Eastern Europe, which was the first case of detection of this type in Spain.

Within the framework of a long-standing collaboration between France and Catalonia on wolf monitoring, a sample was sent for analysis to the French laboratory Antagene, which confirmed the coincidence with an individual previously located in the Burgundy region, in eastern France. Specifically, it was the individual named by scientists GW1909m, which had also been previously located in Germany.

No evidence of the presence of this individual has been found in the Alta Ribagorça region since February 2023.

Travels in France and Germany

The same wolf detected in Catalonia was already located on 17 June 2022, when a driver saw a canid running along a road in the commune of Fleurey-Les-Faverney (Haute Saone, France). He identified it as a wolf-like canid, managed to take a photo and alerted local authorities. Thanks to this tip-off, an officer of the French Biodiversity Agency (OFB), a member of the monitoring network for the species in France, managed to collect a bit of fur on a wire fence at the place where the witness indicated that the wolf had passed by. The fur was subjected to genetic analysis. The reference laboratory Antagene, in charge of the genetic analysis of wolves in France, found the DNA haplotype called "w1", which is quite unusual for wolves in France.

Since this individual carried a genetic trait that occurs frequently in Germany and adjacent areas in central and northeastern Europe, a sample was sent for cross-analysis at the German reference laboratory. The cross-validation revealed that this sample matched perfectly with a male scientists had named GW1909m, already known in the German genetic database.

Thanks to fecal samples analysed there in August 2020 by Senkerberg Research Institute, it is known that GW1909m was born in a group located near Nordhorn (Lower Saxony), a few kilometres from the border with the Netherlands. The analysis made it possible to assign this individual to its birth group, where it was detected again in May 2021. Genetic evidence shows that GW1909m must have been born in the spring of 2020, as its parental group did not reproduce before that year.

Dispersal capacity of wolves

Wolves (Canis lupus) are spreading all over Europe thanks to a strict legal protection implemented since the end of the 1970s. The recolonisation of new areas has occurred from Italy all the way to the Alps and also from the centre of Europe to the plains of Germany and western Poland.

The species is known for its behavioral plasticity and long-distance dispersal ability, which can extend for hundreds of kilometres. Wolf GW1909m is an example of the behavioral plasticity and physical capabilities of this large wild canid. Its journey is especially impressive considering that the animal did not travel through large wild areas, but dispersed over such a long distance across the anthropogenic or anthropised landscapes of western Europe.

Although the current fate of GW1909m is still unknown, it remains to be seen whether future genetic analyses will be able to re-detect this animal, or even its offspring.

Iberian, Italian and central wolf populations are still somewhat isolated, apart from a few documented cases of dispersal. Breeding events among these three genetic lineages of wolves have never been recorded until now, and scientists would agree that these long-distance dispersal events are important in connecting distant wolf populations and preventing genetic isolation and inbreeding.

Monitoring the wolf in Catalonia

Wolf populations practically disappeared from Catalonia at the beginning of the 20th century. From 2003 onwards, the first identifications began to be made, especially in the Cadí and Ripollès regions. Twenty years later in Catalonia there is no established breeding population of wolves, although there is the presence of isolated individuals, which are animals that come from the natural dispersion of the wolf population present in France; therefore, all of them of Italo-Alpine origin.

Currently there are four wolf specimens genetically identified in Catalonia, all males; in the last 5 years no females have been detected and, therefore, no evidence of reproduction.At present there are four genetically identified specimens of wolves in Catalonia, all of them males; in the past 5 years no females have been detected and, therefore, there is no evidence of reproduction. The management of wolves in Catalonia is carried out by the Directorate General of Environmental Policies and Natural Environment of the Ministry for Climate Action, Food and Rural Agenda, while the Rural Agents' Office, of the Ministry for the Interior carries out and coordinates the monitoring actions on the ground.