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.
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!
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.
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!1
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.