At least eight sandhill cranes have been injured or killed on a Richmond, B.C., golf course in the past six years, says a wildlife biologist who's urging more protection for the lanky birds.

Myles Lamont says flying golf balls are the likely culprit, smashing into the metre-tall birds without warning and leaving them with fractures, broken bones and internal injuries.

Since May, at least three birds at the Country Meadows Golf Course and Restaurant have been injured and one chick was killed, said Lamont, who has helped the golf course with its sandhill crane population since 2013.

That year, a golf ball shattered a crane's leg on the Richmond course. The bird later was later fitted with a prosthetic limb.

The most recent incident earlier this week involved a sandhill crane that suffered a broken leg. Lamont said the bird may have to be put down depending on the severity of its injury.

Watch the injured bird hopping on one foot:

The sandhill crane suffered a broken leg after likely being struck by a golf ball. 0:41

"It's incredibly frustrating," Lamont told CBC News.

"Obviously, none of the staff like to see birds injured. They're all fairly keen about having them there. But nonetheless, until last week, there's been very little — almost nothing — that's been done by the golf course to mitigate this."

Susan Hogler, the owner of Country Meadows, said signs were recently put up on the course asking golfers to let birds pass before teeing. The golf course advertises the cranes on its website and Hogler says golfers love having them around.

"We are trying our best to prevent any injuries. They've been around for a very long time and I know of very few problems with them," Hogler said, adding that she's only been aware of two injured birds, including the most recent one with the broken leg.

Better protections

The sandhill crane, known for its spindly legs, grey plumage and red forehead, is the most common crane species in the world. The bulk of that population is centred in Canada where the bird is protected under the federal migratory birds convention act.

The species isn't considered at risk in B.C., but the population in the Fraser Valley has dwindled as the region's wetlands, where they normally reside, dry up, Lamont said. He estimates that about 12 breeding pairs remain in the area.

"When you start taking out breeding adult birds, it's incredibly devastating to that reproductive population because there just so few left," he said.

One of the few remaining wetland habitats in the region lies directly to the north of the golf course, Lamont said. But it's also drying out and that has meant more vegetation blocking the cranes' views of predators and forcing them to venture to the golf course.

Lamont said he wants the golf course to either install temporary fencing at the back of the property where cranes and their chicks can safely reside or to have staff move the birds off the course.

He's also sent letters to municipal, provincial and federal governments asking them to remind the golf course of its legal obligations in protecting the wildlife.

In a statement, the B.C. Ministry of Environment said it was aware of the crane injuries and deaths at the golf course.

"We are dedicated to working with the golf course to determine next steps," a spokesperson wrote.

Hogler, the golf course owner, said staff already patrol the course on carts and try to herd the cranes away. But she said she's open to greater protections.

"If it's a doable, valid plan that someone would help us with, of course," she said.