New Brunswick

Tracking the monarch: A trip inside the best place to observe the butterfly migration

One of the best places to catch and tag monarch butterflies is at Point Lepreau, but few people have ever seen what happens there because of tight security at the nearby nuclear plant.

Volunteers spend the first few weeks of September catching and tagging monarchs at Point Lepreau

The tiny observatory at Point Lepreau, one of the most southern points of mainland New Brunswick. The Saint John Naturalists Club has been counting seabirds during migration since the mid-'90s. They began tagging migrating monarch butterflies here in 2006. (Steven Webb/CBC)

You've likely never been to one of New Brunswick's most important resting spots for migrating monarch butterflies.

That's because the place they choose to build up energy for their migration to Mexico is on one of the most southern points of New Brunswick's mainland — and, as the saying goes, it's as safe as a church.

"It's the closest thing to being an offshore island that you can get without being on a boat," said Jim Wilson, a member of the Saint John Naturalists Club, "So you've got a sort of a microclimate here that's very different."

The very tip of Point Lepreau is a perfect spot for the monarchs, with low grasslands awash in blooming thistles and goldenrod this time of year, that sit protected from the harsh winds that blow along the Bay of Fundy.

WATCH | Saint John naturalists at work on monarch butterflies migrating south.

Monarchs use Point Lepreau to power up before odyssey south

2 months ago
The Saint John Naturalist Club has been tagging butterflies at their seabird observatory at the tip of the point, by the nuclear plant property. 4:10

And the butterflies can feed on nectar and rest here without much fear of being harassed by humans. That's because they benefit from some pretty heavy security.

To get to the site, you have to pass through the gates of N.B. Power's nuclear generating station, one of the province's most secure facilities.

For our trip, we had to submit information weeks in advance for background checks, and we were escorted to and from the site.

It's something members of the Naturalists Club have become used to.

Volunteer Janet Kempster stalks a monarch in a field of wildflowers at Point Lepreau. Catching the butterflies is a lot harder than it looks. (Steven Webb/CBC)

They've been coming here since the mid-'90s, when the group established a seabird observatory after discovering this lighthouse site, owned by Fisheries and Oceans Canada, was a perfect spot to watch migrating birds.

But Wilson and his fellow volunteers also began to notice something else.

"In the fall, when we were down here looking at the sea ducks going by, we'd notice monarch butterflies," Wilson said.

"After a while, we became aware that there's more monarch butterflies here at the tip of Point Lepreau than [we were] seeing anywhere else in the province."

Each monarch is slipped into a glassine envelope, normally used to protect valuables like photo negatives, while they wait to be tagged. (Mike Heenan/CBC)

Wilson tucked that information away. 

Then, in the early 2000s, he and his wife Jean visited a bird observatory in Cape May, N.J. That's where they witnessed tagging of monarch butterflies and thought they should get involved.

"By the fall of 2006, we had purchased a few tags in the fall from Monarch Watch, the University of Kansas, the people behind the tagging effort," Wilson said. "And so we began to tag a few monarch butterflies here."

They started off slow, tagging just 25 or so in the first year. But those numbers have now grown into the hundreds.

In that time, they've developed a theory as to why so many monarchs stop here before crossing open water.

Success. One of about 70 monarchs caught by volunteers on a sunny afternoon at Point Lepreau in early September. (Mike Heenan/CBC)

"They're kind of funnelled out on the tip of the point by the geography. And when they get here, their next instinct is to cross the water from Point Lepreau over to the coast of Maine, or perhaps Grand Manan and then the coast of Maine," Wilson said.

In order to tag the monarchs, you have to catch them.

On this sunny day, there is no shortage of monarchs.

They're everywhere, fluttering by on the wind, travelling from bloom to bloom.

The volunteers are wielding nets on long poles, but catching the monarchs is no easy task.

A monarch butterfly receives a tag at the Saint John Naturalists Club observatory at Point Lepreau. Thousands of monarchs stop in the area during the first few weeks of September to refuel on flowers before heading south to Maine on their winter migration to Mexico. (Mike Heenan/CBC)

"They're quick as a cat," Wilson said.

The technique is to approach the butterfly as it sits on a flower. Once you're close enough, it requires a quick strike and a flick of the wrist in a flourish to close the net, ensuring the butterfly can't escape.

Club president Ray Riddell admits he didn't earn his title with his butterfly catching prowess.

"Yeah, I have really poor technique," he said with a laugh, "I got 12 … but there are ones that got away. There are a lot that got away."

Still, by mid-afternoon Wilson estimates the group has captured 60 to 70.

Each monarch is slipped, wings together, into a glassine envelope, usually used to protect photo negatives or valuable trading cards. 

Jim Wilson tags a monarch in the club's observatory at Point Lepreau. The small tags are held on with adhesive. In 2012, two monarchs tagged at Point Lepreau were found at the wintering grounds in Mexico, more than 4,000 kilometres away. (Mike Heenan/CBC)

As the volunteers return with dozens of envelopes, the tagging begins in the tiny observatory building.

First, the butterfly is tested for a parasitic infection known as O.E., or Ophryocystis elektroscirrha.

Volunteer Janet Kempster takes a surface sample from the butterfly's abdomen by pressing a piece of scotch tape against it. She uses a microscope to look for the parasite.

Infected butterflies are not released back into the wild.

If the butterfly is parasite free, a small numbered paper tag is applied to the outside of its lower left wing using a toothpick.

Then Wilson applies slight pressure to the tag to let the warmth of his fingers activate the adhesive.

The sex of the butterfly is recorded, by looking for a small pheromone sac on the inside of the back wing. Only males have this.

Then the butterfly is released to continue its southward journey.

Jean Wilson prepares to release a monarch, the tag clearly visible on the lower wing. The tag is placed so it can be easily seen and photographed. (Mike Heenan/CBC)

Wilson believes this effort is an important part of understanding how the monarch butterflies in this region are doing.

"I think we're seeing better reproduction in recent years in New Brunswick," he said. "And the only way to really tell is to be here at a place like Point Lepreau and compare what we see one year to the previous year, the previous year to that."

But it's also part of the global effort to protect the endangered species by learning its migration routes. 

"If we tag a monarch here and it's seen en route somewhere between here and Mexico and you put a pin on the map -- it's seen further down, you put another pin on the map … So if we can better map out the places that they're migrating along through, then greater conservation efforts can be made to protect the monarchs' migration."


Steven Webb


Steven Webb is a producer for CBC based in Saint John.


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