WWF-Canada Blog:
Freshwater


Canada Water Week: Five freshwater species that need healthy waters

It’s no secret around the office that I’m a bit of an animal nut. I (of course) love animals like pandas, elephants and tigers as much as my other WWF colleagues do, but I’m also fascinated by some of the more obscure and unknown species that people perhaps don’t appreciate as much as I think they should! I am talking about freshwater species – you know, those creatures that live in and around water that are often covered in scales, scutes, or sometimes even feathers.

I am convinced that if everyone knew just a little bit about some of these creatures, then everyone might appreciate them a little bit more, — maybe even feel compelled to do more to protect their freshwater homes! Since our theme for Canada Water Week is Water Heroes, I’m going to tell you about five freshwater species from across the animal kingdom that I find interesting, and why I think they deserve to be recognized as heroes too, during this week of celebration!

1.  Spring Peeper (Pseudacris crucifer)

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A Spring Peeper (Pseudacris crucifer) – one of the earliest frog species to start calling in the spring ©Brian Lasenby

The sound of the spring peeper is a familiar and welcome one throughout much of Canada, all the way from Manitoba to Prince Edward Island. Spring peepers are one of the first signs of spring, as they are one of the earliest frogs to start singing, sometimes even when there is still snow on the ground!

Spring peepers, like all amphibians, depend on freshwater habitats. They mate and lay their eggs in water, and are often found living near it as adults. They’re sensitive to the impacts of urbanization, as wetlands become drained, reducing the amount of available habitat for these frogs.

Fascinating Fact: Spring peepers don’t freeze to death, even when the thermometer drops below the freezing point! Even though spring peepers are amphibians (and are therefore ectotherms, which means they’re unable to regulate their own body temperature), spring peepers don’t freeze to death even when temperatures drop to a few degrees below freezing. This is due to their specialized blood chemistry. That’s why they’re able to withstand the cold temperatures and start calling early in the spring. How cool is that?

2.  Common Loon (Gavia immer)

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Common Loon (Gavia immer ) swimming with a chick on its back © Frank Parhizgar/WWF-Canada

It’s hard to talk about favourite Canadian freshwater species without mentioning the Common Loon. Like the Spring Peeper, the Common Loon has a massive range, from Newfoundland and Labrador all the way to British Columbia. Like the Spring Peeper, the call of the Loon is a familiar and welcome sound for many people as they relax on their docks at the cottage in the summer.

Loons prefer quiet and remote freshwater lakes for breeding. So if you have a nesting pair of loons on your property, it’s a good indicator your lake is fairly undisturbed and supports a healthy ecosystem.

Fascinating Fact: Loons are very well adapted for life on water and in the air, but are not very agile on land. Loons have many adaptations which allow them to hunt, swim and dive in the water. While most birds have hollow bones, loons have solid bones. This adaptation makes them less buoyant, and therefore better at diving underwater to great depths to catch fish to eat.

3.  Lake Sturgeon (Acipenser fulvescens)

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Lake Sturgeon (Acipenser fulvescens), one of Canada’s largest and most ancient fresh water fish, swimming underwater. ©Eric Engbretson Underwater Photography/WWF-Canada

Lake Sturgeon are one of my favourite freshwater species, and I’ve spoken about them before in previous blogs. Sturgeon are fascinating for many reasons: they’re one of the largest freshwater fish in Canada and can attain over 3m in length (10 feet) and 180kg in weight (400 pounds). They can live over 100 years and are a member of a family of fish that has existed and changed very little since the age of dinosaurs.

Lake Sturgeon are found in many of the lakes and rivers of Alberta, Saskatchewan, Manitoba, Ontario and Quebec. Despite their name, they’re adapted to and rely on rivers during all or part of their lives. Because Sturgeon need healthy rivers to survive, they’ve been described as very large “canaries in the coal mine” for river ecosystems. Survival and recovery of Lake Sturgeon is dependent upon maintaining their habitat including the conservation, protection and restoration of water flows.

Fascinating Fact: Unlike most fish, sturgeon don’t have scales! Instead of scales, sturgeon are covered in rows of bony plates called scutes. These scutes also covered the early sturgeon species that existed some 200 million years ago. The sturgeon of today have evolved very little since that time period, giving them the reputation of being “living fossils”.

4.  Blanding’s Turtle (Emydoidea blandingii)

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WWF’s Monte Hummel, admiring the beautiful yellow throat of a Blanding’s turtle (Emydoidea blandingii) as part of a field study project to track and monitor Blanding’s turtles in the wild © Emily Giles

Who doesn’t love turtles? Turtles are one of the easiest species to showcase when talking about freshwater species, as they have an endearing quality that most people enjoy. Blanding’s turtles have a beautiful bright yellow chin and throat which makes them easy to identify, and a highly domed shell.

Blanding’s turtles are primarily aquatic and spend most of their time in freshwater habitats like lakes, streams, marshes, and swamps. They are currently listed as Threatened under Canada’s Species at Risk act – being at risk from habitat loss and road deaths.  And because this species has such beautiful colouring, it‘s often the victim of poaching in the wild for the pet trade.

Fascinating Fact: Just like our friends the sturgeon, turtles have been around this planet for millions of years! The oldest turtle fossil can be dated back 220 million years, meaning it showed up 23 million years after the dinosaurs. I shared more Fascinating Facts about turtles back in July, 2014.

5.  Freshwater Benthic invertebrates (aka – bugs!)

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One of our Loblaw Water Fund grantees, Living Lakes Canada, searching for benthic invertebrates to measure water health in the Flathead Valley, BC © Living Lakes Canada

I saved the creepiest and crawliest group for last. This group of animals is an important one, and likely the one that people know the least about. Did you know that certain species of benthic invertebrates (meaning species with no backbone, such as worms, snails, leeches, etc.) that live in freshwater are very sensitive to certain kinds of habitat disturbance, like pollution? We use benthic invertebrates here at WWF as part of our Freshwater Health Assessments.

Benthic invertebrates live under water in the bottom substrate of lakes and rivers for at least part of their life cycle. They’re important indicators in part because they cannot move away to avoid polluted waters, whereas fish and other animals can swim away, and then return again later if and when the condition improves. Therefore, a sample of invertebrate species may indicate what pollution was in that ecosystem at one point in time, even if it’s not currently there at the time the sample was taken.

For example: many worms and leeches are able to tolerate pollution well, so you can find them in both polluted and non-polluted rivers. Other species, like caddisflies, mayflies and stoneflies, are very sensitive to water pollution. So you will typically not find them in a water sample from a polluted or unhealthy water body.

Fascinating Fact: Diversity matters! When evaluating the health of a river, just because you have a large number of bugs doesn’t mean it’s healthy. Having a large number of leeches (a pollution tolerant species) doesn’t necessarily reflect healthy water. Instead, a large number of different kinds of species is what to look for – a term that biologists refer to as species richness.

All throughout Canada Water Week we’ll talk about cool water species, including another benthic invertebrate group which is in trouble in Canada and in many places around the world. Stay tuned!

During Canada Water Week, show your support for our rivers, lakes and streams. Join the hundreds of Canadians working across the country to protect water health. You, too, can become a Water Hero by making a donation to our Loblaw Water Fund projects.