The Bem-Te-Vi (or Great Kiskadee in English), is a perching bird. It is also what is known as a large tyrant flycatcher, which perches high up looking for insects to catch in-flight and the brightly-colored bird is known to populate the tropical areas of South America. Its signature call sounds like “BEE-tee-WEE”, where it gets its name in Portuguese from (because it sounds like bem-te-vi, meaning “I saw you well” in English).
In order to protect its young, it employs a mobbing behavior against preditors in which it individually or collectively harrasses the unwelcome visitor by making swift diving motions. If you’ve lived in Brazil, you may not have been able to recognize the bird, but surely you’ll recognize the bird call below.