Enhancing the reproduction of blue-throated macaws in Bolivia

Posted September 9, 2015

The Zoo continues to support the Bird Endowment’s Nido Adoptivo Saving the Blues program to enhance the reproduction of blue-throated macaws in the wild in Bolivia.

Blue-throated macaw pair
Blue-throated macaw pair

The critically endangered blue-throated macaw (Ara glaucogularis) is only known to survive on private ranches in one small region of northern Bolivia known as Los Llanos de Moxos with a population estimated at 350-400 individuals. It relies on cavities in palm trees as nest sites, but often loses out on nest sites due to competition from other macaws, toucans, bats and large woodpeckers.

The goal of the Nino Adoptivo Saving the Blues program is to increase the annual reproductive output of blue-throated macaws by providing nest boxes. The first nest boxes were installed in 2007, and more have been added over the past eight years to total 60 nest boxes in 2014-2015 season.  Nest boxes are monitored twice a month by a field biologist who records the nest box contents, usage and inter-species interactions.

Nest box adopted by the Cincinnati Zoo
Nest box adopted by the Cincinnati Zoo

The 2014-2015 season was the program’s most successful year to date. A total of 10 blue-throated macaws fledged out of four nest boxes. An additional nest box was used by a pair of blue-throated macaws, but no chicks were fledged.  This brings the total to 56 macaws fledged from nest boxes since the program’s beginning.

Young macaws in a nest box
Young macaws in a nest box

Other species continue to use the nest boxes as well, including blue-and-yellow macaws, white-eyed parakeets and black-bellied whistling ducks. However, changes made in the design of the wooden nest boxes to better suit blue-throated macaws over other species, such as reducing the size of the entrance hole, seems to be curbing some of the competition.

Blue-throated macaws using a nest box
Blue-throated macaws using a nest box

For this upcoming breeding season (2015-2016), the program will expand by placing 15 additional nest boxes in a new area. The program will also experiment with new, wider nest box designs to see if giving them more space will lead to a larger number of eggs laid per clutch. Another experiment will try using a more natural-looking nest box, essentially a hollowed out chunk of a dead tree trunk, to see if it is more attractive to the macaws since 36 of the current nest boxes were not used this past season.

saving the blues