Habitat associations of small mammals in southern Brazil and use of regurgitated pellets of birds of prey for inventorying a local fauna

We inventoried terrestrial small mammals in an agricultural area in southern Brazil by using trapping and prey consumed by Barn Owls (Tyto alba) and White-tailed Kites (Elanus leucurus). Small mammals were trapped in three habitat types: corn fields, uncultivated fields ("capoeiras"), and native forest fragments. A total of 1,975 small mammal specimens were trapped, another 2,062 identified from the diet of Barn Owls, and 2,066 from the diet of White-tailed Kites. Both trapping and prey in the predators' diet yielded 18 small mammal species: three marsupials (Didelphis albiventris, Gracilinanus agilis, and Monodelphis dimidiata) and 15 rodents (Akodon paranaensis, Bruceppatersonius iheringi, Calomys sp., Cavia aperea, Euryzygomatomys spinosus, Holochilus brasiliensis, Mus musculus, Necromys lasiurus, Nectomys squamipes, Oligoryzomys nigripes, Oryzomys angouya, Oxymycterus sp.1, Oxymycterus sp.2, Rattus norvegicus, and Rattus rattus (Linnaeus, 1758)). The greatest richness was found in the uncultivated habitat. We concluded that the three methods studied for inventorying small mammals (prey in the diet of Barn Owls, White-tailed Kites, and trapping) were complementary, since together, rather than separately, they produced a better picture of local richness

Urbanization altered latitudinal patterns of bird diversity-environment relationships in the southern Neotropics

Given the global expansion of urbanization, it is crucial for planning to understand how that process affects spatial patterns of diversity. At broad geographical scales, climatic conditions such as temperature or rainfall usually explain those patterns. Our objective was to analyze and compare the species richness-environment relationships and the distance decay in similarity of bird communities between urban centres and less intensively modified adjacent rural areas along a latitudinal gradient in the southern Neotropics. We surveyed birds in 15 urban centres and their adjacent rural areas from 26° to 38°S and compiled temperature and rainfall data. We performed regression analyses and Mantel tests to explore latitudinal changes in bird species richness and taxonomic composition as a response to those climatic variables in urban centres and in rural areas. Results showed that species richness decreased with latitude in rural areas, and temperature and rainfall accounted for that decline, but remained relatively constant in urban centres. The difference in species richness between urban centres and rural areas was larger at lower latitudes. Similarity in the composition of bird assemblages declined with distance at a similar rate in both urban centres and rural areas; however, similarity was higher between urban centres than in rural areas at any given distance. Environmental differences due to temperature and rainfall partially accounted for the distance decay in similarity for both urban and rural areas. The impact of urbanization on bird species richness seems to differ according to the climatic context in which urbanization develops, and it is expected to be higher in tropical than in more arid environments. Our study remarks the importance of considering urban systems as components of larger ecological systems.Fil: Filloy, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Grosso, Sabrina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Bellocq, Maria Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentin

Arenavirus infection correlates with lower survival of its natural rodent host in a long-term capture-mark-recapture study

Parasites & Vectors 2018, Vol. 11:90Background: Parasite evolution is hypothesized to select for levels of parasite virulence that maximise transmission success. When host population densities fluctuate, low levels of virulence with limited impact on the host are expected, as this should increase the likelihood of surviving periods of low host density. We examined the effects of Morogoro arenavirus on the survival and recapture probability of multimammate mice (Mastomys natalensis) using a seven-year capture-mark-recapture time series. Mastomys natalensis is the natural host of Morogoro virus and is known for its strong seasonal density fluctuations. Results: Antibody presence was negatively correlated with survival probability (effect size: 5–8% per month depending on season) but positively with recapture probability (effect size: 8%). Conclusions: The small negative correlation between host survival probability and antibody presence suggests that either the virus has a negative effect on host condition, or that hosts with lower survival probability are more likely to obtain Morogoro virus infection, for example due to particular behavioural or immunological traits. The latter hypothesis is supported by the positive correlation between antibody status and recapture probability which suggests that risky behaviour might increase the probability of becoming infected.DOI 10.1186/s13071-018-2674-