The Screaming cowbird (Molothrus rufoaxillaris) belonging to the family Icteridae, is among the avian brood parasites the most specialized species.

Daniel Mello, birdwatching guide and partner of our institution, made the first record of this species at REGUA, in an open area close to the headquarters. A juvenile (rufous plumage) was spotted flying with a flock of Chopi blackbirds (Gnorimopsar chopi). Insects, seeds and on occasions fruit, are part of its diet.

It occurs in most of eastern Brazil, from Rio Grande do Sul to Piaui State.