Monday, March 20, 2023

 New Brunswick

Effort to restore endangered 'Goldilocks' plant to Kouchibouguac sees early success

Gulf of St. Lawrence aster disappeared from the park in 2000 after major storm surge

A small green plant, with many blossoming small flowers on a sandy beach
A relative of dandelions and daisies, the Gulf of St. Lawrence aster is only found on coastlines in eastern N.B, P.E.I and the Magdalen Islands. It is listed as endangered. (Submitted by David Mazerolle)

Known as a Goldilocks plant, the Gulf of St. Lawrence aster is pretty particular about where it lives.

Conditions have to be "just right" for it to thrive and that means the people who are trying to save the endangered plant first have to figure out exactly how it likes its bed, so to speak.

"It grows where there's salt, but it doesn't tolerate too much," said David Mazerolle, a botanist who is working to protect the species at Kouchibouguac National Park, around 100 kilometres northeast of Moncton.

"And the plant also needs some kind of storm disturbance to come and wipe the slate clean of other species, because this is a plant that doesn't really compete very well with other kinds of vegetation. So you'll usually find it on shores that are almost just plain bare sand with not much else growing there. So places that were hit by storm waves."

And therein lies the problem. 

The aster, which is only found in a few sites in eastern New Brunswick, P.E.I. and the Magdalen Islands and nowhere else in the world, has proven to be very vulnerable to the effects of climate change.

A man stands on a stony coastline.
David Mazerolle is an ecosystems scientist and botanist with Parks Canada and is leading the effort to save the Gulf of St. Lawrence aster in Kouchibouguac National Park. (Submitted by David Mazerolle)

The two known populations in Kouchibouguac disappeared when a powerful storm hit the region in October 2000.

After a lot of searching over several years, scientists came to the conclusion it no longer existed inside the park's boundaries.

So, in 2016, they began the process of trying to reintroduce it.

That's not easy, especially considering it is not a perennial plant. Instead, it drops its seeds and dies.

"So the persistence of these populations really depends on the presence of new seed coming into the ground and that's what we usually refer to these things as — seed banks," Mazerolle said.

"And they are kind of what they sound like. It's just a bank of available healthy seed that remains in the soil that will be there just in case the right conditions come up for germination and growth."

A young man and woman stand over a table full of tiny seedlings in a greenhouse.
Students at UPEI survey Gulf of St. Lawrence asters being grown in greenhouses. Parks Canada is using the seedlings to try to reintroduce the plant at Kouchibouguac National Park. (Brian Higgins/CBC)

The seeds for the restoration effort came from the University of Prince Edward Island, where botany professor Christian Lacroix has been studying the Gulf of St. Lawrence aster for years.

They then set about trying to find out exactly what this picky little relative of the dandelion and the daisy really likes. It was a steep learning curve.

"I guess our success rate was a bit spotty." Mazerolle said.

"What we thought we knew or understood of the habitat wasn't necessarily as solid as we first thought. So we picked about 30 locations and about four of these locations actually produced a good number of seeds, and through that work we were actually able to get a more solid understanding of exactly what the habitat really looks like."

Eventually they started to get it right.

"So at this point we've got two sites in the park that have been supporting the species for six years now … We've had challenges, but it's what we would call a success story for sure."

a man squats on a sandy beach as he plants a seedling of an aster.
While easy to grow in a greenhouse, the aster is very picky about its coastal habitat. Mazerolle calls it a Goldilocks species - everything has to be 'just right.' (Submitted by David Mazerolle)

Mazerolle said they've produced about 7,200 plants in the park since the project began in 2016.

But there's still no real way to protect the asters from major storm surges, beyond ensuring there are enough seeds in the soil to start anew when conditions are right.

Mazerolle said every time the region is hit by a powerful storm, he can't help but wonder if the progress they've made in recent years will be obliterated.

"I believe last year we had about 150 plants when we last checked the sites, and that was prior to [post-tropical storm] Fiona. I did visit the sites just the week after Fiona hit, and I wasn't able to find any plants left," he said.

"But it doesn't necessarily mean that they weren't there. One of our introduction sites was completely flooded and the plants could not be seen. You were walking in several feet of water."

Fiona also brought opportunity to the Kouchibouguac shoreline.

A closeup op a tiny aster seedling.
A seedling planted by crews at Kouchibouguac National Park. (Submitted by David Mazerolle)

"I did take plenty of notes on new habitat patches that were created by Fiona. So I guess you would say the dance continues."

Mazerolle said the Gulf of St. Lawrence aster is easy to grow in a greenhouse, and the program is inexpensive compared to other species restoration projects.

"I think we've shown that it can be done, and there's definitely good justification to be plugging away at it more in coming years."

Mazerolle said the plant is rare in number, but it is also unusual in that it is unique to Atlantic Canada.

"This species would have evolved around 10,000 years ago in our region, and there are very few endemic species in our region. So it really is something that's special."

No comments: