NEW ORLEANS – The coronavirus pandemic canceled this year’s flights to count the only natural herd of whooping cranes – the first time in 71 years that crews in Texas have been unable to take an aerial view of the world’s rarest cranes.
The U.S. Fish and Wildlife Service has records of such surveys for every year beginning in 1950, Wade Harrell, whooping cough recovery coordinator for the U.S. Fish and Wildlife Service, said in an email on Wednesday.
The flock breeds in Canada and in winter on and around the Aransas National Wildlife Refuge in Texas, where the survey is conducted.
Current protocols call for roughly six flights, each with a pilot and at least two observers, often from different parts of the country, in the confined space of a small aircraft, Harrell said.
“We decided to stop aerial photography this winter as COVID-19 cases are currently rising,” he said in a press release last week.
Reaching 5 feet tall from their black feet to the little red caps on their heads, whooping cranes are the largest birds in North America. They are white with black wing tips, and their wingspan is more than 3 meters wider than a full size pickup truck. They mate for life.
There are only about 825 – most of them in the natural herd, which is also the only one that doesn’t need human help to keep their numbers up. Habitat loss and hunting had reduced this herd to 15 in 1941.
It is disappointing not to take the survey as people look forward to hearing about the annual population increase, said Liz Smith, national program director for the International Crane Foundation, in a telephone interview on Wednesday. The pandemic also prevented Canada’s Wood Buffalo National Park from doing its usual count.
The Fish and Wildlife Service, as well as state and conservation groups, have been working for decades to build two more herds to protect the Canada-Texas herd against disease, storms, or other damage.
In addition to the birds that are kept captive for breeding, there are approximately 85 birds in a flock learning to migrate from Wisconsin to Florida in ultra-light aircraft from 2001 onwards. A non-migratory flock begun in southwest Louisiana in 2011 has 75 birds.
Juveniles raised in captivity were added to these herds every year until last year. Due to pandemic restrictions, there was “essentially no” captive breeding in 2020, so no juveniles could be added to either herd, said Sara Zimorski, a biologist with the Louisiana Department of Wildlife and Fisheries.
The absence of a year from the survey will not materially detract from the federal agency’s ability to monitor trends, both Harrell and Smith agreed.
“What we need to know is how well the cranes are doing in their Texas winter landscape and whether tagged birds have arrived in their wintering areas,” Smith said.
Citizen scientists have long helped track whooping cranes through the Texas Parks and Wildlife Department’s Texas Whooper Watch program, the federal agency said. High quality photos of banded crane cranes can also be uploaded. They contain information about when and where they were admitted to follow up via a new online form on the foundation’s website.
Smith said she photographed a bird in the Aransas Refuge with a small aluminum tape, indicating that the U.S. Fish and Wildlife Service tagged it during a trip in the 1970s and 1980s.
The whooping crane is likely to be at least 38 years old, she said.
Smith said the cranes often live around 24 years in the wild, but birds that old are rare.
“The re-documentation of this large whooping cranes was so inspiring and informative about the recreational potential of this species,” she wrote in an email on Wednesday.