Blue Tits: Mass Die-Off in Germany
Since the beginning of March, an unusually high number of blue tits have been observed in Germany appearing sick and dying shortly afterwards. The pathogen responsible for the die-off has now been identified: it is a bacterium called Suttonella ornithocola, which causes pneumonia in the birds.
Since the beginning of March, an unusually high number of blue tits have been observed in Germany appearing sick and dying shortly afterwards. The pathogen responsible for the die-off has now been identified: it is a bacterium called Suttonella ornithocola, which causes pneumonia in the birds.
Pathogen identified: Suttonella ornithocola
«Suttonella ornithocola kills almost exclusively tits, particularly the smaller tit species, of which the blue tit is by far the most common in German gardens,» said NABU federal director Leif Miller. «It is likely that coal tits, crested tits, marsh tits and willow tits are also affected. The larger great tits fall ill less frequently.»
By 22 April, a total of 13’800 cases had been reported to NABU from across Germany within just twelve days, affecting approximately 26’000 birds . The Lower Saxony State Office for Consumer Protection and Food Safety (LAVES) has now detected Suttonella ornithocola in tits from the districts of Ammerland and Diepholz. Almost simultaneously, it was announced by the Chemical and Veterinary Investigation Office Münsterland-Emscher-Lippe that the same pathogen had been found in four examined blue tits from the Steinfurt district in North Rhine-Westphalia. In all districts where the bacterium has been confirmed, the map of suspected cases reported to NABU also shows an elevated reporting rate.
The bacterium has only been known since 1996, when it was first described in Great Britain, where it occurs regularly across the country but has not yet caused large-scale mass die-offs. It was not until 2017 that it was detected outside Great Britain for the first time — in Finland. In April 2018, Suttonella ornithocola was detected in Germany for the first time, affecting several tits during minor disease outbreaks in the southern part of North Rhine-Westphalia. Miller: “The widespread, large-scale occurrence this year is unprecedented for this pathogen. In addition to Germany, at least Luxembourg and Belgium are also affected.”
The pathogen poses no risk to humans or domestic animals. However, since birds may also have died from other diseases and can generally carry multiple pathogens, caution should always be exercised when handling dead birds. The species extinction crisis is exacerbated by such epidemics.
Measures and Reporting
In order to determine the extent, geographical spread, and progression of the epidemic, NABU continues to call on the public to report cases of sick or apparently disease-stricken birds via its online form at www.NABU.de/meisensterben .
“In affected gardens, attractants such as feeding stations and bird baths must be removed immediately so that birds are less likely to infect one another,” advises Miller. “Social distancing also helps reduce transmission in bird epidemics.”
Sick tit 
Sick tit 
Sick tit
To allow affected bird populations to recover as quickly as possible, it is important to provide good conditions for the upcoming breeding season. A nature-friendly garden offers an especially rich food supply for hungry young birds. NABU has compiled tips for a bird-friendly garden at www.nabu.de/vogelgarten .
How severely tit populations have been affected by this bird disease, which is new to Germany, will be revealed by the results of the major NABU garden bird count «Stunde der Gartenvoegel» from 8 to 10 May.
