The Birds of the World account for this species includes a description
as a "primitive,"
non-parasitic cowbird", but "sometimes is a nest parasite"
and describes the behavior that Coty observed:
A collective agonistic display, Leaf Gathering, occurs throughout year;
display includes singing by most interacting individuals, birds hold bits
of vegetation (leaves, bark or twigs) in bill, assume Bill Tilt (Bill Up or
Head Up) posture; fighting or supplanting may occur, yearlings stay at edge
of group in "submissive postures" (Fraga 1991). Leaf Gathering displays
involve 8 - 26 birds, last 4.3 - 21 min, and occur on ground or in trees; 7
of 22 known contexts involved attendants of 1 nest responding to a
traveling group with fledglings (Fraga 1991).
On Sat, Mar 15, 2025 at 3:05 PM Constanza Ehrenhaus <cxe1169...>
wrote:
> Hi Club,
>
> Last week I had the good fortune to take a trip to visit my family in
> Buenos Aires. The breeding season there is long because of the benign
> weather, and birds are still building nests and feeding chicks. One of the
> species I had the luck to enjoy is the Grayish Baywing, a social icterid
> that raises its own young. One of the days my family and I witnessed an
> interesting behavior, and I cannot find any information about it, so I am
> curious to know if any of you have ever seen anything of the like and if
> you have any insight.
>
> There were about 12-20 Grayish Baywings gathered on the lawn. They were
> calling and singing to each other, and some birds were picking up dry
> leaves from the ground and showing them to each other. Other birds would
> then pick leaves and show them back to the first birds. There were even
> some birds cutting dried leaves from the shrubs above. Some birds
> (juveniles?) were engaging in begging-like behaviors, but no feeding was
> happening. After a while, they took off flying. There are still couples
> feeding chicks in the area, as I've seen them flying with food into the
> cavities where the chicks wait.
>
> I thought it was an interesting interaction, as I had never seen something
> like that before. Maybe other more experienced birders have?
>
> Have a lovely weekend!
>
> Coty
>
>
> --
> Constanza Ehrenhaus.
>
>
