TransLink has employed a team of winged avengers as part of an aerial assault on a common cause of SkyTrain maintenance issues.

A team of peregrine falcons and their handlers are taking part in a six-week pilot project meant to scare off pigeons, which are often a cause of issues at stations.

The cooing convicts leave droppings and make passengers nervous. They also wander onto tracks and set off intrusion alarms, bringing the trains to a halt. In 2015, a nest fire caused hours-long delays on the Expo Line.

"They're very frustrating," TransLink spokesperson Chris Bryan said.

So TransLink is using peregrine falcons, a natural predator of pigeons, to scare the birds out of the way. Handlers and birds from Raptor Ridge Birds of Prey began wandering SkyTrain stations last month as part of an $18,000 trial.

The results have been mixed.

Pigeons are stubborn, and often return to the dry, heated stations once the falcons have left.

"They've got pretty good eyes too," Raptor Ridge Birds of Prey owner Kim Kamstra said.

So the falcons have to hide in carriers, then come back out when the pigeons return. The hope is the pesky birds will learn the stations aren't safe, and move on to other locations.

The peregrine falcon is a common bird of prey found in most parts of the world. The species is known for its speed and can fly at more than 320 km/h when chasing prey.

With a report from CTV Vancouver's St. John Alexander