The Unicolored Blackbird is in one of my eBird checklists entered long after the fact. I checked my records and I think it is a transcription error as I typed it instead of submitting an Excel file or something similar. I did see Unicolored Blackbirds in Rio's Zona Sul but not at the Botanical Gardens. I saw them at Lagoa Rodrigo de Freitas, which, in fact, is not that far from the Botanical Gardens. I was staying at the Brazilian Navy's hotel (early November 2000), which is in the west side of the lagoon near Ilha Piraquê. One day, early in the morning, I walked the perimeter and soon after I had started my walk, I flushed a small flock of blackbirds, ~6 or so, from some vegetation on the banks, 2 of them alighted not very far from where they had flushed and I had a good look at them with my binoculars. One I identified as a Unicolored Blackbird in female/immature plumage and the other seemed to me to be an adult male. Besides the plumage of the female-plumaged bird, the beak shape and size also helped in the identification. I had seen this species before, on a trip to the Pantanal in 1986. On a marsh, on the road from Cuiaba to Barao de Melgaco. There were illustrations in Sick's book and photos in Dunning's book which were the references I had used them to prepare myself. On the trip in 2000 I had with me Pena and Rumboll's book, Narosky and Yzurieta's book and color copies of the plates in Ridgely and Tudor. So I felt pretty sure about the ID.