Peregrine falcon falco peregrinus in Brazil: natural history through the lens of citizen science

Brazil is an important wintering area for Falco peregrinus, specifically for the subspecies F. p. tundrius and F. p anatum. Using data from WikiAves, we analyzed and discussed aspects of the species natural history, including migratory behavior, geographical distribution, diet, and ecological interactions. Peregrine Falcons were recorded in the country from October until April. Our data suggest that adults can arrive up to a month earlier than juveniles. Individuals have been recorded in all 26 states and there was no significant difference in their geographical distribution in relation to subspecies or age, but there is an apparent lack of records in the Center of the country. Our results showed that in Brazil peregrines prey mainly on Columbiformes and Charadriiformes. Some individuals share the same perch and engage on agonistic interactions with other bird species, usually mobbing or kleptoparasitism.

O Brasil é uma importante área de invernada para Falco peregrinus, especificamente para as subespécies F. p. tundrius e F. p. anatum. Utilizando dados provenientes do WikiAves, nós analisamos e discutimos aspectos da história natural da espécie, incluindo o comportamento migratório, distribuição geográfica, dieta e interações ecológicas. Os falcões-peregrinos podem ser avistados no país entre outubro e abril. Nossos dados sugerem que adultos chegam até um mês antes dos juvenis. Indivíduos foram registrados em todos os 26 estados e não existe nenhuma diferença significativa na distribuição geográfica devido à subespécie ou faixa etária, mas existe uma aparente escassez na região Centro Oeste. Nossos dados apontam ainda que no Brasil os falcões-peregrinos se alimentam majoritariamente de Columbiformes e Charadriiformes. Alguns indivíduos dividem o mesmo poleiro, registramos também a ocorrência de interações agonísticas com outras espécies, geralmente tumulto ou cleptoparasitismo.

Ophiophagy in Brazilian birds: a contribution from a collaborative platform of citizen science

Citizen science is the interaction of the non-academic community in scientific studies, often extended to collaborative platforms. We analyzed 168 photographs shared in a Brazilian citizen science platform to understand the feeding interactions between birds and snakes in Brazil, comparing our findings to published data. We searched for patterns in bird taxa and behaviour correlated with ophiophagy, snake groups most vulnerable to predation, and biases resulting from citizen science data. Records were made mostly in south-eastern and southern Brazil. Both birds and snakes recorded are primarily diurnal, terrestrial, and use open habitats. Predators represent especially birds of prey, but nine other families were observed, and most of the identified snakes belong to Dipsadidae and Colubridae. Venomous snakes were observed, suggesting that birds must deploy strategies to avoid injuries. Finally, we added a new vertebrate item to the diet of the white-faced ibis (Plegadis chihi). Data biases of citizen science platforms, which in this work include differences in the number of records between different geographic regions and periods of day, must be considered. However, this kind of data can be a powerful tool for understanding life history patterns and natural history of birds and other animals.

Distribution and migration phenology of Purple Martins (Progne subis) in Brazil

Purple Martins (Progne subis) are Neotropical migratory birds that breed across North America and spend their nonbreeding season in South America, primarily Brazil. They have been in a long-term population decline over the last five decades. There are several suggested causes for the decline, but to begin understanding the conservation needs of this species, it is necessary first to fill existing knowledge gaps about migration timing, distribution, and habitat use in Brazil. The presence of this species across most of Brazil makes it difficult to keep track of seasonal or long-term changes in its distribution without careful, widespread data collection. Citizen science offers an emerging opportunity to address knowledge gaps of roost distribution and phenology. Here, we compiled Purple Martin records from citizen science platforms, scientific collections, and bibliography to produce an overview of the distribution and phenology of the species in Brazil. It is present in most Brazilian states, but records are concentrated in the Amazon region. Previously known large roosts in southeast Brazil, especially in the state of São Paulo, have decreased in number of individuals over the last decade. Most records are from September to April, although phenology varies with latitude. In the equatorial region (5°N–5°S), which is crossed by all populations that come to Brazil, the number of reports shows strong temporal variation, probably related to the timing of migration in different populations.

Breeding review of Gray-hooded Gull Chroicocephalus cirrocephalus in Brazil with contributions on nests and egg biometry

The Gray-hooded Gull (Chroicocephalus cirrocephalus) is a seabird distributed in almost all South American countries. However, breeding information on the species in Brazil is scarce. In this study, a literature review and searches in online databases (WikiAves and eBird) were carried out to gather breeding information on the species in the country and new records of nests of the Gray-hooded Gull were registered on the northern coast of the Rio de Janeiro state. Literature review indicated breeding records in Rio Grande do Sul, Rio de Janeiro and Rio Grande do Norte states. On WikiAves, 19 records of the species with nests, eggs, chicks and breeding colonies were reported between 2009 and 2020, in Macau, Rio Grande do Norte and one adult hatching at Rio Grande do Sul. In August 2019, two nests were recorded at Ubatuba lagoon (22°09′S and 41°18′W) in the Restinga de Jurubatiba National Park, in the Quissamã municipality in Rio de Janeiro. The nests were described and monitored during five weeks. Each nest contained two eggs and was built with the grass Paspalum vaginatum. Over time, the eggs were degraded and disappeared from the nests, without signs of hatching and possible predation. This study compiles for the first time all the breeding information on the species in Brazil and contributes with data about nests and egg biometry.(AU)

Breeding review of Gray-hooded Gull Chroicocephalus cirrocephalus in Brazil with contributions on nests and egg biometry

The Gray-hooded Gull (Chroicocephalus cirrocephalus) is a seabird distributed in almost all South American countries. However, breeding information on the species in Brazil is scarce. In this study, a literature review and searches in online databases (WikiAves and eBird) were carried out to gather breeding information on the species in the country and new records of nests of the Gray-hooded Gull were registered on the northern coast of the Rio de Janeiro state. Literature review indicated breeding records in Rio Grande do Sul, Rio de Janeiro and Rio Grande do Norte states. On WikiAves, 19 records of the species with nests, eggs, chicks and breeding colonies were reported between 2009 and 2020, in Macau, Rio Grande do Norte and one adult hatching at Rio Grande do Sul. In August 2019, two nests were recorded at Ubatuba lagoon (22°09′S and 41°18′W) in the Restinga de Jurubatiba National Park, in the Quissamã municipality in Rio de Janeiro. The nests were described and monitored during five weeks. Each nest contained two eggs and was built with the grass Paspalum vaginatum. Over time, the eggs were degraded and disappeared from the nests, without signs of hatching and possible predation. This study compiles for the first time all the breeding information on the species in Brazil and contributes with data about nests and egg biometry.

Breeding review of Gray-hooded Gull Chroicocephalus cirrocephalus in Brazil with contributions on nests and egg biometry

Abstract The Gray-hooded Gull (Chroicocephalus cirrocephalus) is a seabird distributed in almost all South American countries. However, breeding information on the species in Brazil is scarce. In this study, a literature review and searches in online databases (WikiAves and eBird) were carried out to gather breeding information on the species in the country and new records of nests of the Gray-hooded Gull were registered on the northern coast of the Rio de Janeiro state. Literature review indicated breeding records in Rio Grande do Sul, Rio de Janeiro and Rio Grande do Norte states. On WikiAves, 19 records of the species with nests, eggs, chicks and breeding colonies were reported between 2009 and 2020, in Macau, Rio Grande do Norte and one adult hatching at Rio Grande do Sul. In August 2019, two nests were recorded at Ubatuba lagoon (22°09S and 41°18W) in the Restinga de Jurubatiba National Park, in the Quissamã municipality in Rio de Janeiro. The nests were described and monitored during five weeks. Each nest contained two eggs and was built with the grass Paspalum vaginatum. Over time, the eggs were degraded and disappeared from the nests, without signs of hatching and possible predation. This study compiles for the first time all the breeding information on the species in Brazil and contributes with data about nests and egg biometry.

Citizen science data reveals the cryptic migration of the common potoo Nyctibius griseus in Brazil

The Common Potoo Nyctibius griseus is abundant, charismatic and generally considered to be sedentary across its range. Using citizen science data from eBird and WikiAves, we demonstrate that the Common Potoo may be a partial migrant whose breeding populations depart southeastern Brazil, Uruguay and northern Argentina in May to August during the region’s austral winter. MaxEnt models revealed that spatio‐temporal shifts in Common Potoo distributions were driven by seasonal changes in temperature and precipitation. We examined potential seasonal detection biases by restricting our analysis to daytime observations and testing for seasonally dependent shifts in distribution for two nocturnal non‐migratory species. Our results provide the first evidence of migration for any member of the family Nyctibiidae. Our approach exposes the potential value that WikiAves data offer towards elucidating seasonal movements of South American birds.