Got some time? Help count whooping crane nests in satellite photos

A collaborative project is encouraging citizen scientists to identify endangered whooping crane nests in Wood Buffalo National Park using satellite images.

Researchers scouring high-resolution satellite imagery “discovered that we could see whooping cranes sitting on nests,” wrote the Canadian Wildlife Service, Parks Canada, the Calgary Zoo, and the International Crane Foundation on their project website.

“We are providing volunteers with new 2021 imagery and will use the ‘wisdom of the crowd’ to identify possible nests that will later be confirmed by the field team through the aerial checks,” the groups continued.

Around 100,000 images taken over a few weeks during the nesting period need to be reviewed.

To volunteer, start with a short training exercise to familiarize yourself with what a nesting crane looks like in a satellite image. Then, join the campaign and let the team know if you see a whooping crane in each image or not.

The team will use an algorithm called object-based image analysis to identify new breeding areas, in addition to aerial surveys and citizen science.

The Aransas-Wood Buffalo whooping cranes winter along the Texas Gulf Coast, then head north for the summer to breed in Wood Buffalo National Park’s many ponds, marshes, and forested areas.

By the most recent count, there are just 500 of the birds in the wild. Biologists only expect to find around 100 nests each year.

Since the 1960s, the team explained, cranes have been counted using aerial surveys, which are costly, time-consuming, biased, logistically challenging, and involve risks to the surveyors.

“We are interested to know if some surveys, particularly in new breeding areas, can be replaced by collection and analysis of satellite imagery,” they wrote.

“Detection of wildlife in remotely sensed imagery, such as very high-resolution satellite imagery, has several advantages over traditional methods, such as being able to cover large, remote and inaccessible areas, collect data more frequently to update population estimates, and minimize disturbance to wildlife.

“Because whooping cranes are large, white birds that nest in open landscapes, it is possible to detect them in satellite imagery.”

Each image shows a section of land 150 metres by 150 metres. The nests are one to two metres in diameter, so volunteers should be able to see nests in the images without having to zoom in.

Because of the distance whooping cranes nest from each other, it’s highly unlikely that more than one nest will be visible in an image.

Some of the images shown are from aerial flights dating from 2017 to 2019, as “combining new imagery and old imagery lowers the chances of overcounting and undercounting nests.”