The Kitimat Valley Naturalists are hoping two new "bat condos" will encourage nearly 2,000 bats to return to northwest B.C. after their maternity roost was demolished over the winter.
The animals had been using Kitimat's old cadet hall to live and raise young over the summer months.
The colony was discovered in 2016, just before the hall was scheduled to be demolished.
"We were completely taken aback," Dennis Horwood, president of the naturalists club, told CBC Daybreak North host Carolina de Ryk.
"No one had any idea that there were bats down there or in that number."
The colony is believed to be one of the largest in British Columbia.
Bats at risk in Canada
Protecting bats has become an important issue in Canada, with the spread of a fungal disease known as white nose syndrome killing millions of the animals in the east and advancing westward.
Maternity roosts are especially important, according to Mandy Kellner, a biologist and coordinator of the B.C.Community Bat Project.
"They reproduce really slowly," she explained.
"Bats will live 20 to 40 years and they're only having one pup a year or no pups if the conditions aren't good."
'Crossing our fingers' for return
After hearing about the colony, the District of Kitimat agreed to delay demolition until after the bats left for winter.
It also purchased replacement homes for the bats and provided space for them to be erected.
Two "bat condos" — large boxes on stilts that can shelter hundreds of bats at a time — were put up this week.
In order to encourage the bats to use the new homes, parts of the old cadet hall have been incorporated into the condos, including trusses on the inside and the installation on the outside of siding from the hall.
Click on the audio labeled 'Bat condos in Kitimat' to hear more about the project to protect bats in northwest B.C.
Horwood said the project will be considered a success so long as a few hundred bats roost in the condos.
"We know if we get a few back, then in a few years they will continue to return, and the colony will establish itself, hopefully to its former numbers," he said.
"We're all kind of crossing our fingers."
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