Minnesota Herps

Turtles, frogs, and snakes-together they’re called “herps.” They rely on the environment around them-the sun, water, or ground-to generate the heat that every creature needs to survive. Despite the cold, Minnesota’s relatively clean water and unpolluted air support a surprisingly high number of herps.

What They Eat
Herps eat a variety of foods-plants, animals, fruit, insects, or a combination of foods. Because they are “cold-blooded” (maintain a low body temperature), they are well adapted to survive in environments where food is sometimes scarce.

Where They Live
Most of Minnesota’s amphibians and turtles live in or near water, while the majority of our snakes live on land. Amphibians are less tolerant of dry conditions, and are generally less abundant in western Minnesota. Reptiles don’t adapt well to cold, so fewer species are found in northern Minnesota.

What They Do
To be active and digest their food, reptiles and amphibians must remain warm. That’s why you’ll often see them basking on rocks in the sun during cool parts of the day, and retreating to the shade when temperatures get too warm.

How They’re Doing
Here in Minnesota, our large population of herps has declined in recent years. Today, about half of our species of reptiles and amphibians are classified as “wild and rare.”

 

Thinking about getting a reptile as a pet or just want to learn more about them, check out our Reptile Care 101 program here at the Minnesota Zoo.

Minnesota Herps

When all else fails, hognose snakes will resort to “playing dead.” They flop over onto their backs, open their mouths, and remain motionless until out of danger.

Turtles have been around since at least the age of the dinosaurs. Over the past 200 million years they have evolved into hundreds of species adapted to habitats around the world.

Frogs sink their bulging eyes into their mouth cavities when swallowing prey to help mash food and push it down their throats.

The sensitive skin of a snake is covered in scales.  Contrary to popular belief, it doesn’t feel slimy, but has a smooth, dry texture.

Herpetology is the study of reptiles and amphibians. Reptiles include turtles, snakes, and lizards. Amphibians include frogs, toads, and salamanders.

Helpful hints for viewing the animals

Look for year-round demonstrations and exhibits featuring Minnesota’s reptiles and amphibians in the Maritz Family Lodge at the head of the Minnesota Trail. In the spring and summer, listen for calling frogs and watch turtles basking on logs in the pond outside the Minnesota Trail.  

Minnesota Herps

Care at the Zoo

Enrichment helps zoo animals demonstrate their natural behavior, adds variety to their day, encourages them to explore their environment, and enhances their well-being. Because herps (reptiles and amphibians) are a large and varied group, keepers provide enrichment based on the what each species might naturally experience in the wild.

Examples of herp enrichment might include adding perches to enclosures to encourage climbing, using water features or misting to assist with the shedding of skin, or changing the material on the surface of the enclosure (e.g. wood chips, soil, or moss) to encourage natural behaviors such as nest-building or burrowing. Because regulating body temperature is so important for herps, providing them with multiple places to take cover (both warm and cool), allows them the opportunity to make choices in their environment.   

Different types of food and the timing of feedings can also be a form of enrichment. Keepers use logs containing insects released on a random schedule to increase foraging behaviors in frogs. For other species, the occasional offering of live prey can be very stimulating. For example, adding earthworms to a turtle’s substrate, or creating a blood trail (made by dragging a dead prey item around the enclosure and then hiding it) in a snake enclosure. Varying the feeding schedule can also lead to an increase in predatory behavior and therefore an overall increase in activity.

Meet the Animals

Get a closer look at Minnesota’s herps by visiting the Martiz Family Lodge at the head of the Medtronic Minnesota Trail. Our large 1,000-gallon tank is home to map, Blanding’s, soft-shelled, and painted turtles. Two smaller exhibits house mudpuppies, garter snakes, and leopard frogs, and we also have a small terrarium featuring tree frogs and salamanders.

Reptiles and Amphibians generally on exhibit:

Turtles	Frogs & Toads
painted	gray tree frog
Blanding’s	American toad
ouachita map	wood frog
soft shell	northern leopard frog
Snakes	Salamanders/Mudpuppies
common garter snake	tiger salamander
	mudpuppy

 

Your visit to the Zoo helps support our conservation programs. You can also sponsor an animal at the Zoo.

 

 

Minnesota Herps

Loss of habitat is the greatest threat to amphibian and reptile populations in Minnesota. Because herps are so sensitive to the world around them, scientists call them “bio-indicators.” Their health often reflects the quality of their environment.

Things you can do

Don’t release unwanted pets or animals from school projects into the wild. Doing so may introduce species that can someday affect Minnesota animals and their habitats.

If you find a frog, turtle, snake, or salamander, watch it, learn from it, and then put it back where you found it.

In Minnesota, female turtles are frequently hit by cars when crossing roads to nesting sites (usually in May and June). If you see a turtle crossing the road, helping it across might save its life. First, make sure it's safe to help-don’t put yourself in danger. Turtles know where they are going, so always move them in the same direction they are traveling (this is not always toward water).

Minnesota’s Deformed Frogs
In 1995, teens on a biology field trip in Henderson, Minnesota documented a surprisingly large number of malformed frogs. Their find attracted world-wide attention. Since then, mutant frogs have been found all over the world. 

What’s happening? Is it pollution, parasites, or increased ultraviolet light? Scientists have recently determined that it may be a combination of all three. A common weed killer runs into streams and ponds where it kills floating algae. This allows more light to reach the bottom, benefiting parasites that then infest the frogs in larger numbers, causing an increase in deformations.

Minnesota Herps

Reptiles vs. Amphibians
How are they different?

	Reptiles	Amphibians
Body Heat	“Cold-blooded”: their body temperature varies with the heat around them.
Skin	Scales or plates (protects)	Moist, breathable (absorbs)
Toes	Claws	No claws
Eggs	Mostly hard, laid on land	Soft, laid in wet places
Young	Miniature form of adults	Mostly different from adults

Frogs and Toads
Turtles and Tortoises
Salamanders, Newts, and Mudpuppies
Snakes

Frogs and Toads
These amphibians lead double lives. When developing into adults, they transform from gills to lungs and fins to legs. Minnesota has 11 species of frogs and 3 species of toads.

All toads are frogs, but not all frogs are toads:

Habitat	Frogs	Toads
	Usually found in or near water	Lives on land, found farther from water
Skin	Thin, smooth, and moist	Thicker, dryer, and warty
Legs	Powerful hind legs; more webbing on toes	Weaker hind legs; hops only a few inches at a time

Frogs and toads on exhibit at the Minnesota Zoo often include the grey tree frog,  American toad, northern leopard frog, and wood frog.

Habitat
Most frogs have a semi-aquatic lifestyle, but their long hind legs and webbed toes making jumping or climbing on land easy.

Diet
Adult frogs feed mostly on insects, using their large bulging eyes and long sticky tongue to detect and capture their prey.

Reproduction
Frogs typically lay their eggs in freshwater puddles, ponds, or lakes, where their gilled larvae (called tadpoles or polliwogs) hatch and develop until they can live on land. At night during the mating season (spring in Minnesota), groups of individual frog species can easily be identified by their loud, distinctive calls.

Turtles and Tortoises
Turtles are reptiles that carry their house on their back. Minnesota can count nine species of native turtles, three of which have become particularly rare.

All tortoises are turtles, but not are turtles are tortoises:

	Turtle	Tortoise
Habitat	Found near water	Live on land, including  desert climates
Shells	Flat and streamlined for swimming	Domed to provide protection against predators
Legs and feet	Longer legs, webbed feet for swimming	Stocky legs, rounded stumpy feet

Turtles on exhibit at the Minnesota Zoo include painted, Blanding’s, ouachita map, and soft shell. 

Habitat
Many of Minnesota’s ponds, lakes, and rivers host turtles, and you’re most likely to see them when they’re basking in the sun for warmth. They tend to be shy and will quickly dive underwater if they sense your presence. Approach them carefully and stay as far back as you can to watch. A pair of binoculars helps.

Diet
Turtles are toothless. Depending on their preferred diets they use a serrated or sharp upper lip to cut through plants or prey. Most turtles are omnivores. They feed on plants, worms, aquatic insects, fish, frogs, and small mammals and birds.

Reproduction
Turtles use their back legs to dig nests on land. After depositing their soft, leathery eggs, they cover the nest with sand or dirt and walk away. If you see turtles walking across land, they’re probably ready to lay eggs. Do not disturb them, unless they are trying to cross a road when your assistance might save their life.                       

Salamanders, Newts, and Mudpuppies
The term 'salamander' refers to both salamanders and newts. The mudpuppy is also considered a salamander. Five species of salamanders are native to Minnesota:
Tiger Salamander (Ambystoma tigrinum)
Spotted Salamander (Ambystoma maculatum)
Eastern Red-backed Salamander (Plethodon cinereus)
Eastern Newt (Notophthalmus viridescens)
Mudpuppy (Necturus maculosus)

Salamanders
Most salamanders have slender bodies, long tails, and four limbs. They look similar in appearance to lizards, except their skin is thin and moist, and they have four clawless toes (lizards have five toes with claws). Most adult salamanders live on land, but many species lay their eggs in water. The eggs hatch into larvae with external gills. Some species (mudpuppies) retain their gills and live out their lives in water. Other species transform into lung-breathing adults that live on land. Salamanders are nocturnal. They can be found under rocks or logs and in steams or moist forests.

Newts
The Eastern Newt (Notophthalmus viridescens) is commonly found in Minnesota. Eastern Newts dwell in wet forests with small lakes or ponds. They need a moist environment with either a temporary or permanent body of water, and thrive best in a muddy environment. They can live in lakes with fish because their skin secretes a poisonous substance in response to being threatened or injured. They have a lifespan of 12 -15 years in the wild, and may grow to 5 inches in length. Eastern Newts eat a variety of foods such as insects, small mollusks, crustaceans, young amphibians, and worms.

Mudpuppies
Mudpuppies (also called waterdogs) are aquatic salamanders. Mudpuppies never lose their gills and spend their entire lives underwater. Adults have bright red external gills that expand or contract depending on how much oxygen is in the water. Mudpuppies also absorb oxygen through their skin and by occasionally breathing air at the surface. Mudpuppies usually prefer shallow lakes and streams that have slow-moving water and rocks to hide under, but have been found in up to 90 feet of water. Their diet consists of insects, small fish, fish eggs, snails, and worms.

Minnesota salamanders on exhibit at the zoo include the tiger salamander.

Snakes
Minnesota is home to 17 species of snakes, although one, the venomous massasauga (mass-as-SAU-gwa) rattlesnake has not been positively sighted in the state for many years. Minnesota’s other venomous snake, the timber rattlesnake, is quite rare and is only spotted occasionally on river bluffs in the southeastern part of the state.

Habitat
These leg-less reptiles slither along the rivers, hilltops, and backyards of rural and suburban Minnesota. In the winter, most Minnesota snakes hibernate below the frost line. They will use rock crevices, ant mounds, or tunnels made by other animals, and sometimes intertwine in large balls with species having similar hibernation habits.

Diet 
Snakes rely solely on animals and insects for food. Depending on the species, in Minnesota their diet may consist of earthworms, insects, frogs, eggs, small mammals, and birds. Snakes track their prey using their forked tongues to collect and “smell” airborne particles. Some species, like milk snakes and bull snakes are constrictors. They squeeze their prey to suffocate it, then swallow it whole. Other species, like the common garter snake, simply snatch their prey quickly and swallow it alive.

Reproduction
Depending on the species, snakes in Minnesota lay eggs or give live birth. The two most well known snakes, the common garter and plains garter, mate in the spring and give birth to between 10-70 or more young in late August to early September, with nearly half of their young dying before reaching 1 year old.

At the Minnesota Zoo, you can see the common garter snake and other Minnesota snakes in the Maritz Family Lodge at the head of the Minnesota Trail.