The monarch butterflies to be released at Head of Tide Preserve Aug. 2 were still in their chrysalises during Belfast Free Library’s outside story hour. But children gathered anyway, with their parents, to hear about Mona the monarch butterfly.

Cyrene Slegona covered the life span of a monarch butterfly in her story to the preschool-aged kids, from its wintering grounds in Michoacan, Mexico, to its migration through North America.

Since Slegona turned 12, she’s been raising monarch butterflies to be released. She continued the practice during her career as a grade school teacher, using the butterflies as an educational tool for students. This year she wanted to release them with the library.

Slegona visited El Rosario, Mexico, a famous monarch sanctuary, and was so inspired by all the butterflies and beauty that she’s already planned another trip to the town. Monarchs live and breed there over the winter in oyamel fir trees before migrating in the spring.

“I went for the first time last year and it was as magical as you can imagine,” Slegona said.

She kept the monarch storytelling positive for the children who attended the event but is aware of threats to the species from human activity. This includes habitat destruction and removal of milkweed, which is the larva’s only source of food, and, more recently, pesticide use.

One butterfly can lay from 300 to 500 eggs and if one of those individuals goes on to be a breeding adult it is considered to be a success.

Monarchs are an indicator species, which means the species is used to determine the conditions of an environment based on fluctuations and health of the population. It’s commonly used as a flagship species to be an ambassador for its habitat or an environmental cause.

Erica Rubin Irish, youth services librarian, hosts the story hour to encourage children to read and help them develop a fun and healthy relationship with books. This is the second outdoor reading, and she thinks it is something that the library will continue doing in the future.

“It’s been really nice. So I think we’ll try to keep doing it,” Irish said. “… It creates a nice social environment to make friends.”

The Belfast library hosts the family story hour and craft event every Friday at 10 a.m. For more information, visit belfastfreelibrary.org.