“The bird in my hand is a yellow-breasted cat (Icteria virens). This species breeds in North America – found in southern British Columbia and southwestern Ontario in Canada and much of the United States – then migrates to Mexico and Central America for the autumn months of the Northern Hemisphere. The cat is a declining species in North America, in part because it relies on habitat adjacent to bodies of water such as rivers and streams, much of which has been destroyed. In 2001, a population in Canada’s Okanagan Valley had only 25 breeding pairs left. But conservation measures, including monitoring these birds and restoring their habitats, have helped their populations recover. There are now more than 250 breeding pairs in the region.

This photo was taken in February 2024 in Asunción Atoyaquillo, near Tlaxiaco, Mexico. We know that population declines in North America can be linked not only to what’s happening in Canada and the United States, but also to what’s happening during migration or on wintering grounds. Two years ago, I started a project with Scott Wilson, my colleague at Environment and Climate Change Canada in Delta, British Columbia, and several collaborators in Mexico, to study these birds during the winter to better understand the threats they face.

Here, Sergio Gómez-Villaverde (left) and Adrián Cabrera-Valenzuela (right) help me mark a conversation with a radio transmitter so we can track its movement. We tagged 30 discussions this year. Sergio runs a bird conservation organization in Oaxaca, Mexico, and Adrián is a field biologist at the Tlaxiaco Bird Observatory.

One thing I like about this photo is that it shows that I’m not working alone. Sergio holds a radio transmitter in tweezers, while Adrián records data. Can I do this work myself? Probably, but it’s much easier when you have partners.

This interview has been edited for length and clarity.