Reserva Ecológica Costanera Sur

Sitio realizado por aficionados a la observación de aves desde 10 de enero 2006

Behaviour - Chalk-browed mockingbird


When a chalk-browed mockingbird is annoyed with the presence of intruder, it lets him know by pouncing on and yelling at him, sometimes with overt attacks. No matter the size of the intruder, the mockingbird confronts him all the same. We have seen the mockingbird face raptors and other unfeathered wild fauna in the reserve, like the black-and-white tegu lizard and the urutu pit viper. It is not always successful. Sometimes it does drive the intruder away, other times it gives up and leaves, but this does not discourage the mockingbird from trying again on another occasion. A mockingbird may act alone or may be assisted by other mockingbirds to stalk the intruder.
A few birds of the reserve display this aggressive behaviour. No doubt the chalk-browed mockingbird is the most contentious of all the passerines in the reserve.
Chimango Caracara
30-04-12 © Juan Pablo Muszkats
Chimango Caracara
30-04-12 © Juan Pablo Muszkats
This chimango caracara sat on a cock spur coral tree occupied by chalk-browed mockingbirds. An unpleasant visitor for the mockingbirds. They tried hard to drive it away but failed. So they left the tree. As the owner of the place the chimango stayed motionless for a while, took off and disappeared from sigh
Roadside Hawk
23-03-19 © J. Simón Tagtachian
Harrassing a roadside hawk
Chalk-browed Mockingbird
22-10-19 © Hernán Tolosa
Harrassing a southern caracara
20-05-12 © Pablo Serur

The voice of the mockingbird led me to a caracara which was tearing off leaves and branches. The yells attracted another five mockingbirds. From a dried tree they swooped down on the caracara. Like the Chimango caracara, the Southern Caracara ignored the attacks even the overt ones. The caracara kept pulling branches for a while and then left.


Chalk-browed Mockingbird
21-10-12 © Juan Pablo Muszkats
Chalk-browed Mockingbird
21-10-12 © Juan Pablo Muszkats
Near the water tank at the Viamonte entrance we saw a tegu lizard and two mockingbirds, which kept harrassing and pecking at the lizard's tail. The mockingbirds were quite convincing and the lizard sneaked away.
Chalk-browed Mockingbird
06-12-17 © J. Simón Tagtachian
Chalk-browed Mockingbird
06-12-17 © J. Simón Tagtachian
Chalk-browed Mockingbird
06-12-17 © J. Simón Tagtachian
Chalk-browed Mockingbird
06-12-17 © J. Simón Tagtachian
Chalk-browed Mockingbird
26-10-19 © Javier Guillermo González
Chalk-browed Mockingbird
26-10-19 © Javier Guillermo González
Chalk-browed Mockingbird
31-03-18 © Pablo Serur
Chalk-browed Mockingbird
31-03-18 © Héctor Horacio García
The chalk-browed mockingbird ran after the urutu pit viper, always from behind. The viper did not bother. Unluckily some visitors got near and the mockingbird left.