A longstanding survey of whooping cranes wintering in Texas has been canceled because of COVID-19 health concerns, the U.S. Fish and Wildlife Service announced Tuesday.
“Due to the close exposure this survey requires and the fact that our pilots and observers often travel in for this effort from different parts of the country, we decided to forgo the aerial survey this winter with COVID-19 cases currently spiking,” said Wade Harrell, USFWS whooping crane recovery coordinator, in a news release. “Fortunately, missing one survey year out of many will not significantly affect our ability to monitor long-term population trends while maintaining the health and safety of our staff.”
A pilot and at least two observers occupy a small plane for up to four hours at a time to conduct the aerial surveys, Harrell said.
Federal biologists have been conducting aerial surveys of whooping cranes on and around their wintering grounds at Aransas National Wildlife Refuge since at least 1950. The surveys provide insight into the long-term population trends of the endangered species that was once near the brink of disappearing.
The whooping crane population is now estimated to be more than 500 birds, according to aerial winter surveys conducted in recent years. All of the whooping cranes alive today, including wild and captive, are descendants of the last remaining 15 cranes that were wintering at the Aransas National Wildlife Refuge in 1941.
Harrell said other activities conducted by partners, such as the Texas Parks and Wildlife Department’s Texas Whooper Watch program, can help fill information gaps that the survey cancellation may create.
The Texas Whooper Watch program allows citizen scientists to report whooping crane sightings and is particularly useful for those spotted outside of the aerial survey area. During the last few years, surveys have shown that whooping cranes are expanding their range outside of the primary survey area at Aransas National Wildlife Refuge.
Depending on available food, each pair of whooping cranes needs 300 acres of habitat to winter and raise their young.
The USFWS is also working with the International Crane Foundation to test a new online application with a small group of citizen scientists to report banded whooping cranes. The information can help the USFWS better understand whooping crane survival patterns through the winter.
Biologists plan to resume the aerial survey in January 2022 and are continuing to mark whooping cranes with telemetry tracking devices as part of an ongoing joint research project between the U.S. and Canada.
“While we are disappointed that the historic aerial survey will not take place this year, we are encouraged by the fact that enduring partnerships enable us to continue to monitor the population this winter in a safe way,” Harrell said.