Fecundidade anual e parasitismo de ninho em uma população do Curutié Certhiaxis cinnamomeus (Aves: Furnariidae) no Sudesde Brasileiro

Abstract

The yellow-chinned spinetail is a Furnariid that, as many other neotropical species, has few aspects of its biology fully studied. It’s been a known host for the stripped cuckoo (Tapera naevia) for years. However, this particular host-parasite system has never been studied. The present study was conducted in a marsh area in the municipality of Santa Bárbara d’Oeste, state of São Paulo, in the reproductive seasons of 2017/2018 and 2018/2018. Through capture and marking of individuals and active search for nests, we built a database about the reproductive biology of this species and the parasitism by T. naevia rates. The first chapter is about the reproductive aspects of the species. The reproductive season lasted from late September to February; The annual fecundity of this population was 0,33 C. cinamomeus and 0.66 T. naevia per female, showing that brood parasitism is the main constrain to the reproduction of C. cinnamomeus in this population. The incubation period was 17 days, and fledging period of 18 days. Reproductive breeding pairs built from 1 to 4 nests during the reproductive season (average of 2.8). The second chapter is about the brood parasitism by T. naevia. Using GLM analysis we tested the hypothesis that the tubular nest entrance might be a constrain to the parasite. Our data didn’t corroborate this hypotheses. Further, no other aspect of nest architecture seems to influence the likelihood of parasitism. The only aspect that showed a negative correlation with the likelihood of a nest being parasitizes by T. naevia was vegetation coverage above the nest. This indicates that T. naevia might use visual cues to locate host’s nests, and vegetation coverage might conceal host activity, making more concealed nests less likely of being parasitized. This study is the first to address specifically the reproductive biology of C. cinnamomeus and this particular parasite-host system.