Using Satellite Transmitters to Aid in Locating Wintering Long-billed Curlew in the Mexicali Valley, Mexico

By Erica Gaeta

Hi my name is Erica Gaeta, and I am currently working on “Bi-national Monitoring of Wintering Long-billed Curlews in Mexicali Valley and Northern Gulf of California, Mexico” project. As part of a bi-national collaborative effort, our team is composed of individuals and organizations from Mexico (CICESE, Terra Peninsular, and Pronatura Noroeste) and the United States (Intermountain Bird Observatory/Boise State University and Sonoran Joint Venture).

Erica conducting wintering curlew surveys.

Our main objectives are to estimate wintering long-billed curlews (Numenius americanus), and gain information on habitat preferences and identify key threats to wintering curlews in the Mexicali Valley and Northern Gulf of California, Mexico.

Long-billed curlews (Numenius americanus). Photo: Erica Gaeta.

Not only is our team bi-national, but so are the curlews we are studying! Our collaborating partner, Dr. Jay Carlisle from Intermountain Bird Observatory/Boise State University has deployed as many as 60 satellite transmitters on curlews during the breeding season in the Intermountain West of the United States. With the use of this technology, we are able to track curlew movements from breeding to wintering sites, which allows us to gain information on the full annual cycle of the largest shorebird in North America. This information is open to the public, and anyone can track curlew movements using Intermountain Bird Observatory’s Curlew Location webpage https://ibo.boisestate.edu/curlewtracking/locations/

Long-billed curlews currently in the Mexicali Valley and Northern Gulf of California, Mexico provided by Intermountain Bird Observatory tracking page.

Currently in the Mexicali Valley there are 3 wintering curlews with satellite transmitters utilizing agricultural habitats named 61 (male, trapped in New Fork, Wyoming), JE (male, trapped in Florence, Montana), and HP (female, trapped in Saratoga, Wyoming). In the Northern Gulf of California there is 1 curlew named Lazara, also known as HX (female, trapped in Island Park, Idaho).

Visit the website Curlew View to track a curlew: https://schall11.github.io/curlew_vision/#

The information provided by the transmitters provides us with a hint as to where to focus our search for wintering curlews. Thus far, we have successfully made several observations of curlew flocks; the largest group we have observed has been 450 curlews in an alfalfa field!

We have observed curlews utilizing several crop types such as alfalfa, wheat, asparagus, sudan grass, onion, and even areas with no vegetation.

The end of our field season is fast approaching as curlews are preparing for their north bound migration to their breeding grounds once again. We will be monitoring our birds with transmitters to see when the migration beings. In previous years it has started mid-march. Stay tuned to hear more about what we see as we explore the Mexicali Valley and the Northern Gulf of California!