Bird populations in both urban and rural areas of France have declined by nearly 30% over the past thirty years, according to data collected by the Muséum national d'histoire naturelle (MNHN). This conclusion comes from annual spring surveys conducted by hundreds of volunteers across the country. Ornithologist Grégoire Loïs, who has been monitoring bird populations in the Yvelines region for five years, highlights the alarming trend and the need for conservation efforts. The Temporal Monitoring of Common Birds (Stoc) is one of the longest-running citizen science projects in France, dating back to 1989. Each year, hundreds of ornithologists are assigned a two-kilometer square area, chosen randomly near their preferred location. Within this area, they visit ten counting points that reflect the variety of local ecosystems, such as villages, forests, and rivers. Counts are conducted three times a year—March, April, and May—with participants recording all species heard or seen within five minutes at each point. The data is then collected, verified, and analyzed by scientists at the MNHN to track population trends over time. According to a 2021 report by the League for the Protection of Birds (LPO), the decline in bird populations is significant and unexpected. Grégoire Loïs, a researcher at the MNHN, notes that while some species have thrived, many others have faced severe declines. For example, the nightingale, once a common sight in the region, is likely gone, with only a few individuals remaining. The European greenfinch has also suffered, losing nearly 70% of its population due to a parasitic disease called trichomonosis. In contrast, "generalist" bird species—those that can adapt to various environments such as cities, rural areas, and mountains—have shown positive population trends. The collared dove, known for its distinctive white neck band, has more than doubled in population over the past 25 years. However, "specialist" birds, which rely on specific habitats, are in trouble. Species found in agricultural areas, like partridges and buntings, have declined by 30% in thirty years, while forest-dwelling birds like woodpeckers and wrens have seen a 10% decline. Even urban birds, such as house martins that nest in barns and garages, have declined by 28% since 1989. The causes of these declines are varied and complex, often linked to habitat changes and environmental pressures. For example, the reduction of wastelands and cavities in renovated buildings has affected urban birds, while intensive agriculture has impacted rural species. Insectivorous birds, which rely on insects for food, have also suffered due to the widespread use of insecticides. A recent study using Stoc data found a strong correlation between the sale of insecticides and the decline of these birds. Grégoire Loïs reflects on his observations, noting the absence of certain species that were once common. During his surveys, he recalls encountering a barn owl in broad daylight and a red-backed shrike, a rare bird that has become increasingly scarce in Île-de-France. The silence of the countryside is now more pronounced, with fewer birds singing than in previous years. The skylark, once a familiar sound in the fields, has seen its population drop by 32% in the last 25 years, symbolizing the broader decline in birdlife across France.