A rare encounter with a rare species

Allison Patrick stands among the tall grasses and wildflowers at NCC's property on Hog Island. (Photo by NCC)

Allison Patrick stands among the tall grasses and wildflowers at NCC's property on Hog Island. (Photo by NCC)

November 8, 2023 | by Allison Patrick

As a conservation biologist with the Nature Conservancy of Canada (NCC) in Fredericton, I spend each summer working in some of the most beautiful parts of New Brunswick and Prince Edward Island. One of my favourite areas in New Brunswick is Belleisle Bay, a long narrow branch of the Wolastoq (Saint John) River. Because NCC’s nature reserve in Belleisle Bay is on Hog Island, I have the great pleasure of canoeing to work! It was during trips to Hog Island that I had two wonderful encounters with monarch butterflies.

Hog Island, Belleisle Bay, NB (Photo by NCC)

Hog Island, Belleisle Bay, NB (Photo by NCC)

Hog Island is in New Brunswick farming country, and like other small maritime islands, it was likely used as a summer pasture for livestock. The island is in the lower part of the massive Wolastoq (Saint John) River basin and is flooded every spring after the snow melts. On my first visit there, I noticed plant debris hanging in the tree branches high above my head. On closer inspection, it turned out to be vegetation deposited by that year’s flood waters.

Related content

Although Hog Island has some trees, such as silver maple, white elm and white ash, it’s mainly a freshwater marsh that is covered in tall grasses and wildflowers, like swamp milkweed. My coworker and I arrived at Hog Island on a morning in July 2018, and the milkweed was in flower. Knowing that milkweed is a delicacy for many insects, we pulled our canoe up to shore to take a closer look.

A monarch caterpillar on a milkweed plant. (Photo by NCC)

A monarch caterpillar on a milkweed plant. (Photo by NCC)

As soon as we stepped out of the boat, we saw an incredible sight: a monarch caterpillar happily gorging on milkweed — the only food these endangered caterpillars can eat! As we explored Hog Island further, we discovered more monarch caterpillars, more milkweed and several adult monarchs in flight.

Monarchs have one of the longest known insect migrations: they winter in Mexico, and in March they start breeding and fly north to lay eggs in the southern U.S. Successive generations migrate northward as far as southern Canada, before reversing their course again in the fall. On average, the journey spans four generations.

Swamp milkweed and monarch among the tall grasses and wildflowers at Hog Island. (Photo by NCC)

Swamp milkweed and monarch among the tall grasses and wildflowers at Hog Island. (Photo by NCC)

In about two weeks’ time, the caterpillar I saw on Hog Island would likely become a super generation monarch butterfly, able make the entire journey to the Mexican home of its great-great-great grandparents to start the cycle over again. Sadly, over the last few decades, this delicate intergenerational migration has been affected by habitat loss, climate change and the loss of common milkweed on farms. Because of rapid population declines and continued threats, monarchs are now at risk of extinction.

This past summer, I returned to Hog Island and was delighted to discover that the monarchs had returned. Not only did I feel lucky to be in the presence of an at-risk species once again, I felt lucky to see evidence that my work and the work of my NCC colleagues is helping monarchs survive in our part of the world.

Looking for an eco-friendly gift idea this holiday season? Give the gift of a monarch butterfly through the Nature Conservancy of Canada’s symbolic adoption program and support conservation efforts that help this species thrive!

Monarch butterflies are one of 17 species and habitat options available for symbolic adoption program. Learn more >

Allison Patrick (Photo by NCC)

About the Author

Allison Patrick is a conservation biologist who works out of the Nature Conservancy of Canada’s Fredericton office

Read more about Allison Patrick.

More by this author »