Relação entre o isolamento social (covid-19) e o número de registros de duas espécies de aves migratórias no estado de São Paulo

Abstract

During the covid-19 pandemic, social distancing was adopted as a measure to curb virus dissemination. As a consequence, there was a reduction in anthropic disturbance in the cities (such as foot traffic, noise, light, and atmospheric pollution). This could have affected the presence of birds in cities and eventually their migratory processes. In this study, it was intended to investigate if social distancing caused by covid-19 pandemic affected the number of records and the migratory pattern of two bird species, the Tropical Kingbird (Birds, Tyrannidae) and the Plumbeous Kite (Birds, Accipitridae) in the state of São Paulo. It was expected that with social distancing, the populations of Tropical Kingbird and Plumbeous Kite would experience less anthropogenic impact, altering their migratory processes, resulting in a change in the migration or return period. Additionally, it was expected to observe a greater impact of social distancing on Plumbeous Kite records, given its sensitivity to urbanization. To answer this research question, records of the species were collected from the eBird and Wikiaves platforms before, during, and after the implementation of social distancing in the state of São Paulo. Data related to day length and social distancing index in the cities of records in the same state were also collected. To analyze the data GLMM analyses were conducted using R Studio. As a result, it was observed that the migratory patterns of the species remained unchanged regardless of social distancing, refuting our hypothesis. A decrease in Plumbeous Kite records was also observed in relation to the increase in the social distancing index in the state. However, the variation in sun length was the variable that positively influenced Tropical Kingbird records, confirming the prediction that social distancing would have a greater impact on Plumbeous Kite records. In conclusion, social distancing apparently did not interfere with the migratory pattern of the species, as migration is associated with the circannual rhythm of birds, which has not changed during the covid-19 pandemic. Nevertheless, there was a negative impact on the number of Plumbeous Kite records, attributed to the limitations imposed by social distancing itself.