The Mariana Crow can only be found on Rota and a successful project recently introduced 14 hand-reared crows into Rota’s jungle in an effort to increase the population. 

Henry Fandel, co-director of the University of Washington's Mariana Crow Recovery Project on Rota, said, "This is our fourth release. We did one in 2018, 2019, 2022, and 2023."

14 Mariana Crows, released over two months, now live independently in Rota’s jungle. It’s a year-long process as they prepare to leave their nest at the San Diego Zoo Wildlife Alliance facility on Rota --  it’s a sign of progress. 

"They are hand-reared by staff at the zoo facility until they can feed themselves food out of a dish or bowl or any kind of enrichment-type food item that is provided to them in their aviary that is hidden in dead leaves or tucked among the branches in their aviary," Fandel said. 

Biologists build temporary aviaries at the release site to introduce the birds to the area where they can acclimate for two weeks -- then they’re set free and monitored by the team. There are just over 200 Mariana Crows in Rota. 

"So it is sort of this perfect balance of good habitat, public land, support from private land owners, and the right mixture of some wild Aga but not too many," he said. 

Researchers put small radio transmitters on the birds like a backpack which is used until the battery dies. "It will tell us…what the status of that bird is. Is that bird still alive and well or has it perished for some reason?" he explained.

They’re monitoring their movement and tracking the bird’s progress as they live in the wild. Fandel said, "The more we follow them the more we see what they are eating, what they are doing and this indicates to us whether they are making that successful transition into the wild."

They’re now preparing to release the next cohort of birds in 2024.