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Fish, Amphibians, Reptiles

Some vertebrates do not need feathers or fur on their bodies to keep warm. That’s because they are ectotherms, or “cold-blooded”. This means that their internal temperature matches that of their environment, which is the case for fish, amphibians and reptiles.

Our country contains about one-quarter of the world’s fresh water. That places a lot of responsibility on Canadians to protect the 230 species of fish that live in the streams, rivers, and lakes. Since all water in Canada eventually flows out to sea, pollutants that enter our streams, ponds, marshes, lakes, or rivers inland will eventually reach the ocean. Even if you live in central Manitoba, you can have an impact on the 400 marine fish species that are found in our coastal water.

Amphibians, represented by frogs and salamanders in Canada, also rely on our freshwater ecosystems to survive. Their eggs do not have hard shells and must be laid in water or in a very humid environment. They do not have scales therefore their skin must remain moist. Most species go through a two-stage life cycle: they hatch into aquatic larvæ (commonly known as tadpoles) which eventually change into air-breathing adults.

Species from two of the four groups, or Orders, of the world’s reptiles are found in Canada: turtles, and lizards and snakes. The scales on their bodies and their hard-shelled eggs make them less reliant on the presence of water, but our turtles need access to both aquatic and terrestrial habitats to complete their life cycle. Snakes and lizards are, for the most part, land-dwellers.

Discover some of our species of fish, amphibians and reptiles in this section!

  • American Eel Parks Canada / Parcs Canada American Eel American Eel American Eel (30 seconds) American Eel (15 seconds) American Eel (Youth) Ocean Commotion (webisode)

    The American Eel (Anguilla rostrata) is a fascinating migratory fish with a very complex life cycle. Like salmon, it lives both in freshwater and saltwater. But its life-cycle is exactly the reverse of salmon’s: the eel is a catadromous species. It is born in saltwater and migrating to freshwater to grow and mature before returning to saltwater to spawn and die. The American Eel can live as long as 50 years.

    It is a long, slender fish that can grow longer than one metre in length and 7.5 kilograms in weight. Males tend to be smaller than females, reaching a size of about 0.4 m. With its small pectoral fins right behind its gills, absence of pelvic fins, long dorsal and ventral fins and the thin coat of mucus on its tiny scales, the adult eel slightly resembles a slimy snake but are in fact true fish. Adult eels vary in coloration, from olive green and brown to greenish-yellow, with a light gray or white belly. Females are lighter in colour than males.  Large females turn dark grey or silver when they mature.

    It is known by a variety of names in Canada, including: the Atlantic Eel, the Common Eel, the Silver Eel, the Yellow Eel, the Bronze Eel and Easgann in Irish Gaelic. In Indigenous languages, like Mi’kmaq, it is known as k’at or g’at, the Algonquins call it pimzi or pimizì, in Ojibwe bimizi, in Cree Kinebikoinkosew and the Seneca call it goda:noh.

    The American Eel is the only representative of its genus (or group of related species) in North America, but it does have a close relative which shares the same spawning area: the European Eel. Both have similar lifecycles but different distributions in freshwater systems except in Iceland, where both (and hybrids of both species) can be found.

    Fish, Amphibians and Reptiles
  • Atlantic Cod Atlantic Cod (Youth) Atlantic Cod (15 seconds) Atlantic Cod (30 seconds) Atlantic Cod

    atlantic codThe Atlantic Cod (Gadus morhua) is a medium to large saltwater fish: generally averaging two to three kilograms in weight and about 65 to 100 centimetres in length, the largest cod on record weighed about 100 kg and was more than 180 cm long! Individuals living closer to shore tend to be smaller than their offshore relatives, but male and female cod are not different in size, wherever they live.

    The Atlantic Cod shares some of its physical features with the two other species of its genus, or group of species, named Gadus. The Pacific Cod and Alaska Pollock also have three rounded dorsal fins and two anal fins. They also have small pelvic fins right under their gills, and barbels (or whiskers) on their chins. Both Pacific and Atlantic Cod have a white line on each side of their bodies from the gills to their tails, or pectoral fins. This line is actually a sensory organ that helps fish detect vibrations in the water.

    The colour of an Atlantic Cod is often darker on its top than on its belly, which is silver, white or cream-coloured. Its exact colour varies between individuals and seems to depend on its habitat in order to camouflage, or blend in: when there’s lots of algae around, a cod can be reddish to greenish in colour, while a paler grey colour is more common closer to the sandy bottom of the ocean. In rocky areas, a cod may be a darker brown colour. Cod are often mottled, or have a lot of darker blotches or spots.

    The Atlantic Cod may live as long as 25 years.

    Fish, Amphibians and Reptiles
  • Atlantic whitefish Atlantic Whitefish (30 seconds) Atlantic Whitefish (60 seconds)

    This species belongs to the salmon family. Both land-locked and anadromous—meaning it spawns in fresh water but spends much of its life at sea—populations were known to occur. However, there is no current evidence that anadromous populations still exist.

    The Atlantic whitefish has silvery sides, a silvery-to-white belly, and a dark blue-to-dark green back. The fish has an elongated body and a mouth at the end of its snout rather than under its head. Adult fish range from 18 to 40 cm in length. The Atlantic whitefish’s dorsal fin and forked tail fin are dusky in colour; the lower fins are light. The Atlantic whitefish also has a small, fleshy fin between the dorsal and tail fins, which is typical of members of the salmon family.

    Fish, Amphibians and Reptiles
  • Chorus Frog Susan Enders Chorus Frogs Chorus Frogs Chorus Frogs (Youth) Chorus Frogs (15 seconds) Chorus Frogs (30 seconds) Wetland Wonderland (webisode)

    There are two species of chorus frogs here in Canada: the Boreal Chorus Frog (Pseudacris maculata) and the Western Chorus Frog (Pseudacris triseriata). Prior to 1989, all Canadian chorus frogs were considered to be one species, as they are very similar – it’s even hard for scientists to differentiate them! Studies determined, though, that they are indeed different. While the Western Chorus Frog might have slightly shorter legs than the Boreal Chorus Frog, and that their respective calls have different structures, genetics have proven this. 

     Boreal Chorus Frog (left), Western Chorus Frog (right)

    Chorus Frogs are about the size of large grape, about 2.5cm long on average, with a maximum of 4cm. They are pear-shaped, with a large body compared to their pointed snout. Their smooth (although a bit granular) skin varies in colour from green-grey to brownish. They are two of our smallest frogs, but best ways to tell them apart from other frogs is by the three dark stripes down their backs, which can be broken into blotches, by their white upper lip, and by the dark line that runs through each eye. Their belly is generally yellow-white to light green. 

    Males are slightly smaller than females, but the surest way to tell sexes apart is by the fact that only males call and can inflate their yellow vocal sacs. Adults tend to live only for one year, but some have lived as many as three years. 

    Their tadpoles (the life stage between the egg and the adult) are grey or brown. Their body is round with a clear tail.

    Fish, Amphibians and Reptiles
  • Coho Salmon Alex Borbely Coho Salmon Pacific Salmon Pacific Salmon (Youth) Pacific Salmon (30 seconds) Pacific Salmon (15 seconds) Ocean Commotion (webisode)

    Adult coho salmon have silvery sides and metallic blue backs with irregular black spots. Spawning males have bright red sides, and bright green backs and heads, with darker colouration on their bellies. The fish have hooked jaws and sharp teeth. Young coho salmon are aggressive, territorial and often vibrantly coloured, with a large orange anal fin edged in black and white.

    Fish, Amphibians and Reptiles
  • Cowichan Lake Lamprey Cowichan Lake Lamprey (Home Grown)
     Cowichan Lake Lamprey

    Lampreys are an amazing group of ancient fish species which first appeared around 360 million years ago.  This means they evolved millions of years before the dinosaurs roamed the earth. There are about 39 species of lamprey currently described plus some additional landlocked populations and varieties. 

    In general, lamprey are one of three different life history types and are a combination of non-parasitic and parasitic species.  Non-parasitic lamprey feed on organic material and detritus in the water column.  Parasitic lamprey attach to other fish species to feed on their blood and tissues. This is why lamprey are often unfairly called “aquatic vampires”.

    Most, 22 of the 39 species, are non-parasitic and spend their entire lives in freshwater.  The remainder are either parasitic spending their whole life in freshwater or, parasitic and anadromous.  Anadromous parasitic lampreys grow in freshwater before migrating to the sea where they feed parasitically and then migrate back to freshwater to spawn. 

    The Cowichan Lake lamprey (Entosphenus macrostomus) is a freshwater parasitic lamprey species. It has a worm or eel-like shape with two distinct dorsal fins and a small tail.  It is a slender fish reaching a maximum length of about 273mm.  When they are getting ready to spawn they shrink in length and their dorsal fins overlap.

    Unlike many other fish species, when lampreys are getting ready to spawn you can tell the difference between males and females. Females develop fleshy folds on either side of their cloaca and an upturned tail.  The males have a downturned tail and no fleshy folds. Lamprey don’t have gills like other fish species but have pores for breathing. These seven gill pores are located one after another behind the eye. 

    There are several characteristics which are normally used to identify lamprey.  Many of these are based on morphometrics or measurements, of or between various body parts like width of the eye or, distance between the eye and the snout.  Other identifying characteristics include body colour and the number and type of teeth.

    Some distinguishing characteristics of this species are the large mouth, called and oral disc and a large eye.  This species also has unique dentition.  For example, these teeth are called inner laterals.  Each lateral tooth has cusps and together they always occur in a 2-3-3-2 cusp pattern.

    Fish, Amphibians and Reptiles
  • Wood Turtle Thinkstock Freshwater Turtles Freshwater Turtles (30 seconds) Freshwater Turtles
    Stinkpot Turtle


    Freshwater turtles are reptiles, like snakes, crocodilians and lizards. Like other reptiles, they are ectothermic, or “cold-blooded”, meaning that their internal temperature matches that of their surroundings. They also have a scaly skin, enabling them, as opposed to most amphibians, to live outside of water. Also like many reptile species, turtles lay eggs (they are oviparous). But what makes them different to other reptiles is that turtles have a shell. This shell, composed of a carapace in the back and a plastron on the belly, is made of bony plates. These bones are covered by horny scutes made of keratin (like human fingernails) or leathery skin, depending on the species. All Canadian freshwater turtles can retreat in their shells and hide their entire body except the Common Snapping Turtle (Chelydra serpentina). This shell is considered perhaps the most efficient form of armour in the animal kingdom, as adult turtles are very likely to survive from one year to the next. Indeed, turtles have an impressively long life for such small animals. For example, the Blanding’s Turtle (Emydoidea blandingi) can live for more than 70 years! Most other species can live for more than 20 years.

    There are about 320 species of turtles throughout the world, inhabiting a great variety of terrestrial, freshwater and marine ecosystems on every continent except Antarctica and its waters. In Canada, eight native species of freshwater turtles (and four species of marine turtles) can be observed. Another species, the Pacific Pond Turtle (Clemmys marmorata), is now Extirpated, having disappeared from its Canadian range.  Also, the Eastern Box Turtle (Terrapene carolina) has either such a small population that it is nearly Extirpated, or the few individuals found in Canada are actually pets released in the wild. More research is needed to know if these turtles are still native individuals. Finally, the Red-eared Slider (Trachemys scripta elegans), has been introduced to Canada as released pets and, thus, is not a native species.

    Fish, Amphibians and Reptiles
  • Hathcling Leatherback Sea Turtle Thinkstock Leatherback Seaturtle Leatherback Seaturtle (30 seconds) Leatherback Seaturtle (60 seconds)

    The leatherback seaturtle is the world’s largest reptile. It is significantly larger than all other marine turtles. The leatherback’s body is teardrop-shaped, tapering at the rear to a blunt point. The carapace, or upper shell, can grow to more than 2 m in length, and the turtle can weigh more than 900 kg. Like all sea turtles, the leatherback has both front and rear flippers, but it is the only sea turtle whose flippers have no claws. Its large front flippers are usually at least half as long as its carapace. The leatherback, like other sea turtles, cannot retract its head or flippers under its shell as tortoises and freshwater turtles can.

    The leatherback is also the only sea turtle that does not have a hard shell or scales. Instead, its carapace is covered with the leathery skin that gives the turtle its name. The skin covers a thick layer of oil-saturated fat and connective tissue and a matrix of small bony plates that fit together, almost like a jigsaw puzzle, to form the shell. Seven ridges run the length of the turtle’s carapace, which is a dark bluish-black colour. Sometimes the turtle’s carapace appears brown when it is seen in the water. The leatherback’s carapace, neck, head, and front flippers are usually covered with white or bluish-white blotches. Its plastron, or bottom shell, is pinkish-white.

    Leatherbacks have a pink patch on the top of the head. Each pink spot, like a human fingerprint, is unique. Scientists are not certain what function the pink spot has, though some think it might help the turtle sense light or determine where it is located in the ocean.

    Fish, Amphibians and Reptiles
  • Northern Leopard Frog Ryan Hodnett Northern Leopard Frog Wetland Wonderland (webisode) Wetlands (30 seconds) Wetlands (60 seconds)
     Northern Leopard Frog

    The Northern Leopard Frog (Lithobates pipiens) is named for its leopard-like spots across its back and sides. Another common name for this frog is the ‘meadow frog’ for its common habitat. Historically, these frogs were harvested for food (frog legs) and are still used today for dissection practice in biology class.

    Northern Leopard Frogs are about the size of a plum, ranging from 7 to 12 centimetres. They have a variety of unique colour morphs, or genetic colour variations. They can be different shades of green and brown with rounded black spots across its back and legs and can even appear with no spots at all (known as a burnsi morph). They have white bellies and two light coloured dorsal (back) ridges. Another pale line travels underneath the nostril, eye and tympanum, ending at the shoulder. The tympanum is an external hearing structure just behind and below the eye that looks like a small disk. Black pupils and golden irises make up their eyes. They are often confused with Pickerel Frogs (Lithobates palustris); whose spots are more squared then rounded and have a yellowish underbelly.

     Colour variations of the Northern Leopard Frog  Pickerel Frog

    Male frogs are typically smaller than the females. Their average life span is two to four years in the wild, but up to nine years in captivity. Tadpoles are dark brown with tan tails.  

    Fish, Amphibians and Reptiles
  • Garter Snake Tony Iwane Western Garter Snake

    The western garter snake (Thamnophis elegans) is a medium-sized snake with a fairly robust body and long tail. From nose to tip of tail adults can measure between 460-960 mm and females are larger than males.

    The head of the western garter snake is large and distinct from its neck. Its crown is black or brownish, depending on which part of western Canada the snake is located. The snake’s upper lip, chin and throat are white or yellow and its eyes are moderately large with a round pupil.

    Sometimes the western garter snake is mistaken for the gopher snake or other garter snakes. A standard way to tell the difference between garter snake species is to look at scale patterns. The western garter snake generally has 10 lower lip scales, and eight upper lip scales. Other garter snakes usually have seven scales on the upper lip. Also, the sixth and seventh upper lip scales are usually enlarged (taller than they are wide). At mid-body, this snake has 21 rows of body scales and only a single anal plate. The scales on its back are keeled — ridged instead of smooth.

    Colours vary with individual snakes, but the prominent yellow to orange stripe running down the western garter snake’s back is easiest to see. There are two lateral stripes on either side of its body — on the 2nd and 3rd rows of body scales — that are similar in color to the stripe down its back. In the space between stripes, the western garter is marked with dark spots or light specks. Like its head, its body has a grayish-green or black to dark brown colour.

    The western garter snake has a grey or beige underbelly colour that may have dark spots, or a dark underbelly with white flecks concentrated down the mid-line.

    Fish, Amphibians and Reptiles