Hemoparasitismo em Lanio melanops (Aves: Thraupidae), em área de Mata Atlântica da Ilha Grande, Rio de Janeiro

Abstract

Several different parasites can affect birds and aggregate with multiple factors, such as reproduction, climate change and stress can cause negative effects in natural populations. According to the level of the impact can even extinct species. Thus, parasitism is considered a selective force as important as predation or competition. Once infected, the birds may remain so for many years or all life. Investigate the blood parasites and their prevalence rates in medium and long term studies allow us to evaluate the actual impact of blood parasitism in host populations. The aim of this study was to identify blood parasites that affect the Black-goggled Tanager (Lanio melanops), and to assess their influence on the weight of individuals, seasonal variation and variation between sex in the Atlantic Rainforest of Ilha Grande. For this, blood smears of 60 captured individuals were made (January 2014 to June 2015), and obtained blood samples for molecular confirmation of the sex of birds with female plumage. We found 58.3% of prevalence for L. melanops on Ilha Grande, value 6-32 times higher than those recorded in other areas of the Atlantic Rainforest. There was no significant difference between parasitized and nonparasitized birds. However, infected females tended to be a bit heavier than nonparasitized. Microfilaria were noted in adults and Trypanosoma sp. was recorded only in juveniles. The presence of Trypanosoma sp. in young birds may be related to the fact that their potential vectors inhabit bird nests. Periods of greater and lesser rainfall had no significantly difference prevalence rate. This effect is probably due to the atypical year where the rains were distributed in unusual ways throughout the year, or the result of an island effect in parasitism. Thus, it is important that long-term studies are performed on parasitism, related climatic data, especially on islands.