Anodorhynchus hyacinthinus kills Cairina moschata in artificial nest in the South Pantanal, Brazil

One of the factors that limit species reproduction is the scarcity of nesting sites. Over the years, the Hyacinth Macaw Project has installed nest boxes in the Pantanal as a short-term alternative, where not only the Hyacinth Macaw (Anodorhynchus hyacinthinus), but other species of birds reproduce successfully. However, the dynamics of cavity occupation is intense in the region, because as natural nests break or are occupied by bees (Apis mellifera), the dispute for artificial cavities increases. In South Pantanal, there were situations where Muscovy Ducks (Cairina moschata) and other birds were found dead inside hyacinth macaw nests. Cameras trap are used in active nests and in December 2016, one of them was installed in an artificial nest with two hyacinth macaw eggs. Near the egg hatching period, a muscovy duck female arrived in the artificial nest, just after the macaws left. The female, intrusive, was caught in the nest by the couple of macaws that, furious, attacked her with violent pecks on her head, killing her in a few seconds. A few days before the images show that several times the Cairina moschata lay on the nest, being expelled by the macaw that was incubating the eggs. Subsequently, only a small piece of egg shell was seen inside the box, as the eggs were probably broken during the agonistic encounter. It was the first time that this situation is recorded, proving the intense behavior of defense of the macaws during the reproductive period and the dispute for cavities for reproduction.