Lucas Carrara, Luciene Carrara, and Lisa Davenport place a tracker on a Blue-throated Macaw to learn more about its movements and migration. Photo by Tjalle Boorsma.
With support from American Bird Conservancy (ABC) and the Mohamed bin Zayed Species Conservation Fund (MBZ), Asociación Armonía (Armonía) has tracked, for the first time ever, Critically Endangered Blue-throated Macaws, which increases our understanding of the birds’ migration patterns, local movements, roosting sites, and home range in Bolivia’s Beni Savannah. This milestone was achieved after three years of attempts to trap and place satellite transmitters on this species.
Numbering fewer than 450 individuals, the endemic Blue-throated Macaw is a bird of mystery. For the last 12 years, Armonía has protected the most important roosting and foraging sites for the northern population of this rare species at the Barba Azul Nature Reserve. However, during the breeding season (November through March), this species leaves the reserve and “disappears” into unknown reaches of the Beni Savannah.
In order to better understand this species’ ecology and conservation needs, Armonía partnered with independent researcher Dr. Lisa Davenport. For two consecutive years, Armonía’s Conservation Director Tjalle Boorsma and Davenport tried to capture a few of these birds, with no luck. During year two, Wendy Willis, ABC’s Deputy Director of International Programs, accompanied the research team at Barba Azul. No matter the techniques tried, the macaws would not cooperate. “The challenges and adventure were magnified by knowing that the satellite transmitters would allow us to learn so much more about the macaw’s northern population breeding locations,” said Willis.
Positive outcomes finally came in August 2019, when Davenport, Boorsma, and Brazilian macaw scientists Lucas Carrara and Luciene Carrara attempted a new capture strategy based on a better understanding of the bird’s behaviors and patterns. Four Blue-throated Macaws were captured and safely handled, and three received transmitters before all were released. Carrying off the transmitters with them, these birds provided long-awaited information on their movements and migration route.
Breeding pair of Blue-throated Macaws. Photo by Tjalle Boorsma.
What we have learned through this geotracking study: During the September foraging period, when the macaws are on-site at Barba Azul, their flight radius is less than 10 km. Once the macaws left Barba Azul at the end of September, they traveled between 40 and 80 km to new locations, again settling for a stationary period, which lasted through the rainy season, their breeding season. Interestingly, they again stayed within a range of under 10 km radius. While they are long distance fliers, the Blue-throated Macaws are not constantly covering great expanses of territory.
Why is migration necessary? We’ve long understood the importance of the Motacú palm (Attalea princeps) at Barba Azul for its provision of forage for the macaws. The difference at the destination location was that mixed in with the Motacú were Moriche palms (Mauritia flexuosa). The Moriche are obviously preferred for breeding, and we were able to conclude that the macaws left Barba Azul in search of mixed Moriche/Motacú forest. These details are crucial for understanding the entire puzzle of what the Blue-throated Macaw needs for breeding success and population growth.
To confirm this, three field teams have logged 340 miles (550 kilometers) of horseback exploring the sites to which the macaws migrated. In order to protect these discovered sites, Armonía is working directly with ranch owners to implement sustainable ranching techniques that help protect the breeding, roosting, and feeding grounds of this majestic species. A sustainable ranching handbook has been published and distributed. The document, in Spanish, can be found here: Sustainable Ranching Guide aims to increase Habitat Conservation in the Beni.
Armonía and ABC are grateful for the generous support of David and Patricia Davidson and an anonymous donor, who helped make the tracking study possible.