When most people think of carnivorous plants, their minds immediately jump to Venus flytraps, which are native to the United States. But did you know that there are carnivorous plants native to Canada? We are lucky enough to have one species of pitcher plant, and several species each of sundews, butterworts, and bladderworts. 

Two beige, herbarium sheets arranged side-by-side with white labels at the base of each. On the left sheet, there are multiple small, dull green, spiky plants, while on the right, there is a much larger pressed plant with yellow and red leaves, and a large yellow flower.
Two carnivorous plant specimens from Canada’s prairies: a slenderleaf sundew (Drosera linearis, left) and a purple pitcher plant (Sarracenia purpurea, right). These are just two of the hundreds of carnivorous plant specimens at the Canadian Museum of Nature. During my time at the museum, I have had the pleasure of imaging many specimens from prairie wetlands thanks to generous contributions from The Mosaic Company – Canada. Image: Marrissa Miller © Canadian Museum of Nature  

Canada’s carnivorous plants employ a wide variety of insect trapping strategies. Pitcher plants, for example, use a pitfall trap. They have a cavity that is filled with liquid, so when insects, spiders, or anything small enough falls in, they become trapped. Even small salamanders end up being digested in the soup of enzymes and microorganisms at the bottom of the deep, narrow pitcher! 

A large cluster of purple and green pitcher plants growing on a patch of boggy ground (left) and an up-close look into a single red and green pitcher plant with leaves of grass in the background (right).
Purple pitcher plants (Sarracenia purpurea) near Upper Head Lake in Algonquin Park (left) and Clyde Fen, AB (right). The leaves of the plant form the “pitcher” also known as a phytotelmata (“phyto” meaning plant, “telmata” meaning pond). Image: (left) Patrick Strzalkowski © Carnivorous Plant Society of Canada ; (right) Kristyn Mayner © Alberta Native Plant Council 

Both sundews and butterworts use sticky traps; gooey mucilage attracts, traps, and digests passing invertebrates on their leaves. Sundews are especially tricky plants. After an animal gets stuck in their mucilage, their leaf closes around it to make sure it doesn’t escape. 

A bright blue damselfly with a long body and wings is stuck to a sundew. The sundew is red and green with leaves covered in spikes with droplets of adhesive on them (left). A pale yellow, star-shaped plant is growing on bare dirt with some grass in the foreground. It has many small insects stuck to it (right).
A damselfly trapped by a sundew (Drosera x obovata) on Vancouver Island (left). A butterwort (Pinguicula vulgaris) covered in insects on Vancouver Island (right). Sundews and butterworts are an example of convergent evolution, when two organisms are not closely related but have similar traits. Butterworts are actually more closely related to bladderworts! Images: Steve Bradford © Carnivorous Plant Society of Canada 

Bladderworts are primarily aquatic, so they have a very different strategy. They have an air-filled cavity with a trap door. When an animal touches the hairs on the outside of the door, it triggers it to spring open and suck the animal and the surrounding water in. 

See a bladderwort in action! 

Even though the bladderwort’s (Utricularia sp.) strategy for capturing prey is very different, their trap is still made of modified leaf material just like all the others described in this article!  

Despite their different meal-trapping strategies, all carnivorous plants have one thing in common: their carnivory is an adaptation to soil that is low in nutrients, and digesting animals gives them the nutrients they are missing. Often, these low nutrient conditions are found in wetlands, which lack the nitrogen and phosphorus that plants need to survive. 

By preserving specimens of carnivorous plants over the past 200+ years, the National Herbarium of Canada at the Canadian Museum of Nature offers scientists, students, and many others a resource for learning about wetland biodiversity and how it is changing over time. This is also key to protecting it. 

I would like to extend a special thanks to the Alberta Native Plant Council (ANPC), Alberta Biodiversity Monitoring Index (ABMI), and The Carnivorous Plant Society of Canada (CPSC) for being instrumental in my research and providing many of the beautiful photos that are included. I would also like to thank The Mosaic Company – Canada, for providing funding to digitize these and other incredibly important specimens.  

For more information on the digitization of specimens, I recommend checking out this other blog posts: https://canadianmuseumofnature.wordpress.com/2020/12/09/science-in-isolation-fieldwork-in-the-cabinets/

1Video by Marmottant CNRS Grenoble.