© Thomas Sattler
Coronavirus influences human behaviour and bird data
Looking back, the corona pandemic leaves its mark on 2020 from an ornithological perspective as well. During the lockdown in spring, the public was asked to stay at home as much as possible. The #stayhomeandwatchout campaign was launched on 19 March, encouraging people to birdwatch in their own gardens or from the balcony. More than 300 participants recorded almost 31 000 observations. While the three most frequently reported species came as no surprise (Eurasian Blackbird, Great Tit, House Sparrow), a few of these garden lists boasted species like Black-crowned Night-heron, Little Owl, Eurasian Pygmy-owl, Griffon Vulture and Blue Rock-thrush. Some birdwatchers obviously live in enviable locations and/ or had tremendous birding luck!
Record number of ornitho entries
Due to the general travel restrictions many observers visited places closer to home, the Alps in particular. The warm summer enhanced this trend. As a result, the records submitted on ornitho. ch from elevations above 1500 m rose by almost a third compared to the year before. The total number of records climbed to 2,5 million, surpassing the peak reached in the previous year by 13 %.
2020 will be remembered as a truly exceptional year. From the point of view of birds, two aspects stand out: (1) an extremely mild winter and (2) (due to the pandemic) people flocking out of doors even more than usual, especially to the lakes and rivers of the Central Plateau.
Mild winter and ideal breeding conditions
Winter was the mildest in Switzerland since records began in 1864. Winter temperatures in 2019/20 were 3 °C above the 1981–2010 average. This presumably explains the very large breeding populations of residents and short-distance migrants in 2020.
An exceptionally warm winter was followed by the third warmest spring with a lengthy dry period. Summer was very warm, but there were no marked heatwaves like in the years before. Many species did well under these conditions. At +15 %, the average increase in the breeding bird indices for long-distance migrants was higher than ever, leading to a new peak in the overall Swiss Bird Index SBI® as well.
Effects of the corona pandemic on wetlands
With the pandemic preventing many alternative leisure activities, the Swiss public flocked out of doors during the fine spring and summer months. While the Swiss lakes and rivers have always been popular destinations, they saw a flood of visitors during the 2020 lockdown, even in nature reserves. The rangers on St. Petersinsel at Lake Biel registered about 55 visitors per hour during spring and summer, or about 150 % of the previous year’s visitor volume. Unfortunately, the influx led to more violations of reserve rules. On the southern shore of Lake Neuchâtel, the number of violations was at least twice that of the year before. Three Purple Heron pairs presumably abandoned their nests due to disturbance.