University of Alberta researchers study owl soundscapes

Industrial noise from the oil patch may be getting between owls and their prey. 

Researchers at the Alberta Biodiversity Monitoring Institute and the University of Alberta are studying whether the birds are still able to hunt down dinner in north eastern Alberta's changing sonic landscape.

"Owls primarily use acoustic cues from their prey to locate them. So, when mice are scurrying around on the forest floor they can pick up those sounds and that helps them to catch their prey," said Julia Schonfield, the University of Alberta Ph.D student leading the research. 

"So it's possible that with a lot of noise in the environment that this would make it a lot more difficult for the owls to catch prey."

Recording owl sounds

Over the last two spring seasons, about 100 recording devices have been set up in the wilderness south of Fort McMurray. 

The small green boxes, with microphones sticking out the sides, are programmed to turn on and off at different intervals. They've been placed at varying distances from the industrial activity. 

"I've got noisy sites and quieter sites of varying sound levels. So, from the acoustic data I'll be able to figure out if owls are living in those areas," said Shonfield.

Several species identified

As researchers wade through the recordings, they're getting to know the distinctive calls of at least six different species of owl. 

"We haven't done very much owl monitoring in northern Alberta, until very recently. And it's a very owl-rich place," said Erin Bayne, the University of Alberta Biology Professor overseeing the project. "A lot of them are species that require older forests, more pristine places, and as development occurs there is a chance that they're going to be reduced in number."

Bayne figures it will be a year or two before they can draw any conclusions. "The noice source – it's certainly seeming to have some sort of effect. What we're trying to sort out now is exactly how far."

With the study results, Bayne says he hopes to be able to make recommendations to oil companies about how to minimize their impact. 

"There's a lot of things that companies can do, in fact some of them are being done as we speak," said Bayne. "During construction activities we can put up walls that will absorb a lot of the sound, sometimes the sites can be sunk lower than the surrounding forest and that reduces the distance over which sound can travel."

The funding for the study comes from oil companies working in the area and the Natural Sciences and Engineering Council of Canada.