Influência da antropização sobre ectoparasitos da avifauna em fragmentos de brejos de altitude no semiárido brasileiro

Abstract

The anthropization of natural environments is a widely distributed phenomenon. Altitude marshes have been suffering several impacts due to human actions, such as agriculture, logging and livestock, which represents a threat to biodiversity in this ecosystem. Human activities can influence important ecological interactions, such as the parasite-host, favoring not only the transmission of parasites between populations of hosts inhabiting small fragments, but also increasing the susceptibility of hosts to diseases. Birds are hosts to several ectoparasites, such as ticks and lice. Countless studies have correlated ectoparasitism by these arthropods with harmful effects on birds, such as impaired immunity and reproductive success and reduced body condition. Knowing that altitude marshes are home to a great diversity of bird species and are exposed to anthropic threats, the objective of this study was to evaluate the influence of anthropization on the ectoparasites of birds in three remaining fragments of altitude marshes located in the municipality of Garanhuns. From August 2018 to July 2019, birds were captured using mist nets, while ectoparasites were collected through visual search and tweezers. A total of 81 species of birds from 18 families were captured, of which 26 species and 12 families were parasitized by lice, while 14 species from 8 families were parasitized by ticks. Of the 546 birds captured, 11.9% (65/546) were infested by 747 lice belonging to 12 taxa, and 4.2% (23/546) by 29 ticks of the species Amblyomma sculptum. Only 1.3% of individuals were coinfested by lice and ticks. Both lice and ticks showed a preference for topographic sites on birds bodies. The presence of Amblyomma sculptum is noteworthy because it is a vector of the Rickettsia rickettsii bacterium, the etiological agent of Brazilian Spotted Fever zoonosis, and is commonly found in areas where original vegetation was degraded, surrounded by human and domestic animals residences, which occurs in the area of study. Although the fragments differ in their environmental and anthropogenic metrics, no significant differences were found between the parasitological parameters of the avifauna between the three altitude marsh remnants.