P.E.I. bank swallows under threat from climate change

Staff from Island Nature Trust, watershed groups and volunteers walked hundreds of kilometres of P.E.I.'s shoreline last summer, looking for colonies of bank swallows.

In 2017, the bank swallow was listed as a threatened species in Canada, having experienced a 98 per cent population decline over the last 40 years.

The staff and volunteers were able to identify about 40 sites across the Island, along both the north and south shorelines.

"The idea was to get a more comprehensive idea of what we have as a population of bank swallows on P.E.I.," said Vicki Johnson, of the Island Nature Trust.

"We tried to take a look at how high up the birds were nesting. We also tried to get a general idea of how many birds were at each colony and also how many active holes or burrows that they were using."

After counting the colonies from the beach, researchers also used a drone to get a closer look at the cliffs where the bank swallows are nesting, and see what is happening on top of those cliffs. 

"With the information that we gained from the footage, we noticed that there's a lot of mowing to the cliffs," Johnson said.

"We also noticed a lot of motorized vehicle activity above there, and also we've noticed that there's very little vegetation that holds that cliff together."

No ice cover

Watershed groups in the Souris and Kensington areas also helped with the surveys of the bank swallows. 

The Souris group surveyed about 30 kilometres of shoreline from North Lake Beach to Johnson Beach, where climate change is having an impact.

"Usually in January, you see a lot of ice cover and there's nothing, so you're going to have storm surges," said Keila Miller, one of the watershed co-ordinators with the Souris and area branch of the P.E.I. Wildlife Federation.

"You're going to have lots of high wind that's going to cut into your banks and your cliffs, and that's going to devastate their habitat."

Miller said the bank swallows return to the same areas every year, sometimes to a very different looking shoreline. 

"After they've travelled, coming back from their winter habitat, they're tired," Miller said.

"Ideally, they will move back into the holes that they excavated last season. But when they have to redo their whole colony, it's pretty devastating for them and their populations."

Bank protection

Johnson said the staff at Island Nature Trust will continue to study the data collected by the video footage, and use it to come up with some best management practices for landowners, to protect the bank swallows.

"We're absolutely willing to work with any landowners that are willing or wanting to make the changes to their land, to not only protect the bank swallows, but also their own land," Johnson said.

"We're hoping that we can at least get a little bit of understanding of how our activities are affecting their populations, so that's really the first step," Johnson said.

"Of course, we'd like to see the population increase, but that will take years from now, to even begin to see the change."

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