Bird Flu Outbreak Kills Cranes: Ornithologists Blame Industrial Farms

On October 23, a residence in Les Aix-d’Angillon, Cher, suffered damage due to a grey crane plummeting onto it, resulting in broken tiles and a large hole in the roof. The French Biodiversity Office retrieved and tested the bird, confirming it was infected with the highly pathogenic avian influenza virus (HPAI).

“We are witnessing a sad rain of flu-stricken birds,” Jean-Noël Rieffel, regional director of the French Biodiversity Office (OFB) in Centre Val-de-Loire, told Decatur Metro. He added that in other regions, cranes have fallen onto highways and into schoolyards.

About 25,000 dead grey cranes have been found along their migration route through Germany, France, and Spain over the past month, according to Alain Salvi, president of the European Working Group on Cranes. The count exceeds 10,000 in France alone. “And that’s only the birds that have been observed. Many more have likely vanished, either into water bodies or consumed by predators,” he further explained.

Each autumn, between 350,000 and 400,000 grey cranes traverse our country in shifting V-formations, heralding the arrival of cooler weather with their distinctive “krrrou, krrrou” calls. About a third of these birds do not travel further, choosing to winter in stopover sites in regions such as Champagne-Ardenne, the major alluvial valleys of the Loire and Allier, or in the Landes at the Arjuzanx nature reserve.

These large, shy grey birds will be less numerous in our fields this winter. However, Alain Savi assures that the current epidemic should not significantly impact the regeneration of crane populations, which are in satisfactory numbers.

The outbreak began in Germany during the second week of October, starting from the northeastern region and then spreading southwest along the migratory path of the cranes.

Beyond the thousands of cranes collected, the H5N1 virus has also caused a massacre in poultry farms over the past month. As of November 12, the Friedrich-Loeffler Institute, the German authority on animal disease outbreaks, reported approximately 1.5 million farm animals either dead from the virus or culled as a preventive measure.

As of the same date in France, the Ministry of Agriculture reported outbreaks in professional turkey, duck, and chicken farms, although the total number of poultry dead or culled was not disclosed. Precautionary measures and biosecurity in farms have been intensified since October 22, shifting the risk level for avian influenza from “moderate” to “high.”

“The significant increase in poultry outbreak incidents in northern and western Germany observed since mid-October 2025 suggests a major shift in the dynamics of HPAI virus infection, likely linked to ongoing post-nuptial migration and the massive death events observed among grey cranes,” stated in the Weekly International Animal Health Surveillance Bulletin (BHVSI-SA).

Essentially, the virus might have been introduced to the farms by the already infected cranes. However, this theory is challenged by ornithologists and ecological associations in Germany.

The Brandenburg branch of the German Union for Conservation of Nature and Biodiversity—among the most affected regions—contends that the poultry industry is the source of the crane contamination, demanding a transparent investigation to trace the infection’s origin, backed by a petition signed by nearly 100,000 people.

“It has not been proven that wild birds are the source of the highly pathogenic H5N1 avian flu outbreaks,” the organization argues. “It’s more likely that wild birds are infected by viruses that have previously circulated within the poultry industry.” It noted that the virus was officially detected in 15 poultry farms across five German states before the first crane deaths occurred.

Most of these infected farms are enclosed, with no outdoor access for the poultry, observes Klemens Steiof, a Berlin-based ornithologist interviewed by Decatur Metro. The possibility of cranes contaminating such sites seems “extremely unlikely,” he said.

Moreover, the naturalist believes that a wild bird infected with the virus that dies no longer spreads the virus, as it is quickly destroyed in nature. He cites the example of wild geese: “Currently, in Germany, the grey cranes have not infected the tens of thousands of greylag geese, bean geese, and laughing geese that share the same habitat.”

According to him, the transmission of this virus from wild birds to other birds occurs only under very specific circumstances: densely populated seabird colonies, significant gatherings of cranes in roosts, or predatory birds or scavengers feeding on an infected bird. Alain Salvi in Lorraine, a region hosting France’s rare white-tailed eagles, fears: “They could get infected by feeding on crane carcasses.”

But how could the virus have transferred from a closed farm to wild cranes? “Unfortunately, veterinarians usually don’t look for vectors between the poultry industry and wild birds,” laments Klemens Steiof, who can only speculate.

The fact that the epidemic began intensely, with many cranes infected within a few days, suggests to him a source near the major crane stopover sites in eastern Germany (states of Mecklenburg-Western Pomerania and/or Brandenburg).

Another factor that might explain why only cranes were affected and not other wild birds: “One possibility could be the use of manure from farms on maize fields, common in Brandenburg, which is buried in the soil,” he suggests. While cranes forage in the soil for leftover maize kernels, wild geese would merely peck at the surface.

He also considers the possibility of ventilation systems. Finally, the transport of infected poultry to slaughterhouses could be another potential source of contamination along the route.

“We demand that manure spreading on fields only be allowed after germicidal treatment,” states Helmut Brücher, a board member of the Brandenburg branch of Bund für Natur und Umwelt (Friends of the Earth Germany).

“It’s easy to blame wild birds and overlook the industrial farming and its consequences. Brandenburg has Germany’s largest egg-laying poultry farms, averaging over 60,000 animals,” he criticizes, calling for more in-depth investigations into large farms.

In France, the League for the Protection of Birds shares a similar stance in a statement from late October: “Formidable incubators of viruses, the high concentrations of poultry promote the emergence of new variants potentially more aggressive, threatening all living beings, including humans.”

The organization once again criticizes the Duplomb law, cursed by all environmental defenders, which relaxes constraints by raising the thresholds at which intensive poultry farms are subject to environmental authorizations. “Unfortunately, France is moving in the wrong direction,” concludes Allain Bougrain-Dubourg, its president.