Snowy owls are migrating south for winter, but many may not survive.

Healing Haven Wildlife Rescue has received 16 calls for snowy owls in distress, but only half of the owls have made it to the facility, located near Dorintosh, Sask.

"By the time people are finding them, they are just so far gone, they are in an extremely emaciated state. And often just the stress of picking them up and driving them here is enough to kind of tip them over the edge, and they don't make it," said Mark Dallyn, the founder of Healing Haven Wildlife Rescue.

He says year to year, he may encounter calls for starving snowy owls, because of the boom and bust of lemming populations, the predator's main food source.

"But this year is different. It's affecting both young owls and adult owls as well. And it's affecting way more than we're used to," Dallyn said.

The first owl came into his care two and half weeks ago. He got a call from conservation officers that were bringing an owl down from Dillion, Sask.

As he was on his way to meet them in Beauval, he found one snowy owl starving on the side of the road.

"That's when I started to wonder what was going on. And honestly, it's been one every day since," said Dallyn.

Dallyn speculates that the snowy owls have been harmed by the summer's wild fires. He says the owls appear to have damaged respiratory systems. He thinks the birds may have inhaled smoke up north during the breeding season. As they journey south, the birds become weak.

"They're in such bad shape that when people find them. Their eyes are closed from being so dehydrated and they literally don't react when you walk over and pick them up," Dallyn said.

The snowy owls are under half of their normal body weight. Dallyn has been giving the eight snowy owls in his care liquid diets though a tube, and will slowly work them onto a more solid diet.

He says it has to be done over a long period of time because the birds' digestion tracts are close to shutting down by the time they reach him.

Captured snowy owl

The snowy owls are so emaciated, they do not react when picked up by wildlife rescuers. (Healing Haven Wildlife Rescue/Facebook)

Dallyn is waiting for conservation officers to decide whether he should release the owls this year, or wait until the spring when the birds would migrate north again.

He says people need to report their snowy owl sightings. He suggests calling the nearest Saskatchewan environment office, the Wildlife Rehabilitation Society of Saskatchewan, or the Healing Haven Wildlife Rescue.

"Even if you're unsure if they need help or not, it's best to give a call. These birds, if they can be caught early enough in their troubles, then they can be saved," said Dallyn.

"It's once they've given up the fight, then we can't bring them back anymore. So the sooner the better."