Every year, for over a decade, Oikonos alongside CONAF has been monitoring the nesting colonies of the Pink-footed Shearwater (Ardenna creatopus) on Isla Mocha, Chile. These data help us understand the shearwaters’ reproductive process, including their arrival and departure times on the island, the digging of their forest floor burrows where they nest, the laying of eggs, the hatching of chicks, and finally, the fledging of the new generation that embarks on their migration to the northern hemisphere.
How do we monitor the Pink-footed Shearwater?
Pink-footed Shearwaters nest on islands with soil suitable for nesting burrows.
We monitor Pink-footed Shearwater chicks using infrared cameras that allow us to see inside their burrows.
Monitoring the inside of the burrows where the shearwaters nest is no trivial task, as these are dark cavities dug by the birds, forming small tunnels in the forest floor among the roots of large Olivillo trees (Aextoxicon punctatum). To assist us in this endeavor, we use a small infrared camera (about the size of a matchbox) attached to a 2-meter-long cable, connected to a tablet or phone for viewing the images. This setup allows us to see inside each burrow by slowly advancing the camera and maneuvering the flexible cable. It can be quite challenging at times; the camera or cable often gets stuck between the roots. However, the reward and excitement are immense when an adult bird, an egg, or a small chick finally appears on the screen, sometimes even being fed by its parents.
Occasionally, we use this camera to inspect smaller burrows to discover what’s inside. Once, we found a baby Chucao (a forest passerine bird endemic to Chile and Argentina), which was very impressive since we didn’t know they nested in soil burrows on Isla Mocha.
Chucao (Scelorchilus rubecula mochae). Subspecies mochae occurs only on Mocha Island. Photo courtesy of Enrique Cruz.
Where on Mocha Island do we monitor the Pink-footed Shearwater?
On the island, we monitor five different sites within the Mocha Island National Reserve, each with its own access path or trail and unique landscapes. Each site offers a distinct experience, always presenting new surprises: the appearance of mushrooms, spider webs glistening with droplets of water, the smell of damp earth, and the charming company of species like Chucaos, along with engaging conversations with coworkers.
Each climb to monitor the sites is an opportunity to renew our energy, as the forest has the power to revitalize us with every tree that surrounds us. This work reminds us of the beauty and mystery of nature, inspiring us to continue protecting and appreciating these wonderful ecosystems.
July 23rd, 2024
Written by: Tiare Varela
Edited by: Gabriela Lamanna & Montserrat Lara