Recovering Mexican Wolves: A Quick Health Check

U.S. Fish and Wildlife Service
2 min readJan 30, 2021

Check out the previous post in this series:
Recovering Mexican Wolves: Every Wolf Counts
Recovering Mexican Wolves: How Radio Collars Contribute to Conservation
Recovering Mexican Wolves: An Aerial Approach

When word comes in that a Mexican wolf has been darted and tranquilized, ground crews of trained biologists prepare to receive and process the wolf.

Four biologists and veterinarians work on a sedated wolf on a table, taking samples and measurements.
A Mexican wolf from the 2019 survey is processed on a table inside a work trailer outside Alpine, Arizona. Photo: Mexican Wolf Interagency Field Team
Four biologists and veterinarians work on a sedated wolf set on top of a blanket on a table outdoors.
For wolves in remote locations, ground crews of trained biologists work on the back of truck beds. Photo: Mexican Wolf Interagency Field Team

The lead processor guides the crew as they conduct a health examination of the wolf, administer vaccines, draw blood, take body measurements, and fit it with a tracking collar. A veterinarian monitors the health of the sedated wolf throughout the process to ensure safety for the wolf and the crew. Finally, a new radio collar is attached and its frequency is recorded along with the rest of the wolf’s information.

Someone measures a wolf paw with a special ruler.
Staff measure a wolf’s length, weight, paw, and teeth size during processing. Credit: Arizona Game and Fish Department

After processing is completed, the wolf is crated and monitored as the sedation drug wears off. Once the animal is ready to be released back to the wild, it’s loaded onto a truck, UTV, or snowmobile ,and it is returned to its territory in the National Forest.

A wolf with a purple radio collar runs out of a dark green crate during a release.
A Mexican wolf is released back into its territory following a capture during the 2019 helicopter count and capture operation with a new radio tracking collar. Photo credit: Arizona Game and Fish Department

This health inspection and the collaring process are repeated multiple times a day for a 10- to 14-day period. Once aerial operations conclude, it’s time to crunch the numbers and determine the previous year’s final population estimate.

What will the 2020 Mexican wolf population count be?

We’ll be reviewing count data over the coming months, and sharing that as soon as it’s finalized. Mexican wolf census data is generally available by spring. This year’s data will help determine the minimum number of living wolves at the end of 2020 and provide a benchmark for recovery moving forward.

Thank you to the many partners who help with Mexican wolf recovery, including Arizona Game and Fish Department, New Mexico Department of Game and Fish, U.S. Forest Service, USDA-APHIS Wildlife Services, White Mountain Apache Tribe, Bureau of Land Management, and the U.S. National Park Service.



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