That's cool, and really good that people are willing and able to do this. Kind of unfortunate that we have to micromanage so much of the "natural" world, though.
Reminds me of a similar project here in the US with whooping cranes (not sure whether they use the ultralight technique anymore, but that was a big part of initial efforts):
We are members of ICF - the pair of sandhills that nest on our property are part of their ongoing research population (this year was the worst breeding season on record, unfortunately). I got to help capture and tag (glue a transmitter onto) a young crane once, which was really cool. That particular crane ended up as coyote food; so it goes.
I agree, it's rather sad but now essential help for the natural world. And I remember seeing something about leading other birds with an ultralight- that's so cool that you have some sandhills in your midst, & that you've had a chance to help.
Rudeness is the weak man's imitation of strength. Eric Hoffer(1902 - 1983)