Maryland’s frog populations include tree frogs, true frogs, and toads, each with distinct calls and skin textures that aid identification. This Maryland Frog Identification Guide will help you tell them apart quickly and confidently. Whether you’re a hiker, a teacher, or just curious, you’ll learn to spot these amphibians by sight and sound.
Frogs are everywhere in Maryland—from the mountains to the coast. They come in different sizes, colors, and patterns. Some are smooth, some are bumpy. Some sing at night, others call during the day. Knowing what to look for makes identification easy.
Maryland Frog Identification Guide
Why Identifying Frogs Matters
Frogs are indicators of environmental health. If you see many frogs, the habitat is likely clean. If you see few, something might be wrong. Learning to identify them helps you monitor local ecosystems and enjoy nature more.
Plus, it’s fun. Kids love it. Adults do too. You’ll start hearing calls you never noticed before.
What You Need To Start
- A field guide or phone app for calls
- Binoculars (optional but helpful)
- Patience and quiet movement
- A notebook to record sightings
Key Features For Identification
Look at these four things: size, skin texture, color patterns, and toe pads. Toads have warty, dry skin. Frogs have smooth, moist skin. Tree frogs have sticky toe pads for climbing.
Calls are also crucial. Each species has a unique sound. Learn a few common calls, and you’ll identify frogs without seeing them.
Size And Shape
- Small (under 2 inches): Spring Peeper, Gray Treefrog
- Medium (2-4 inches): Green Frog, Leopard Frog
- Large (over 4 inches): Bullfrog, American Toad
Skin Texture
- Smooth: True frogs (Green Frog, Bullfrog)
- Warty: Toads (American Toad, Fowler’s Toad)
- Granular: Some tree frogs
Color And Pattern
- Solid green: Green Frog, Bullfrog
- Spotted: Leopard Frog, Pickerel Frog
- Gray or brown: Gray Treefrog, Spring Peeper
- Bright colors: Eastern Spadefoot (rare)
Common Frog Species In Maryland
Here are the frogs you’ll most likely see. Each entry includes size, color, call, and habitat.
American Bullfrog
This is the biggest frog in Maryland. Adults reach 6-8 inches. They are green or brown with a pale belly. Their call sounds like a deep “jug-o-rum.” They live in permanent ponds and lakes.
Green Frog
Similar to bullfrogs but smaller (3-4 inches). They are bright green with a yellow throat. Their call is a single “gunk” like a banjo string. Found in marshes and streams.
Northern Leopard Frog
Medium-sized with round dark spots on a green or brown background. They have a white belly and a distinct call that sounds like a low snore followed by clicks. They prefer grassy wetlands.
Pickerel Frog
Looks like a leopard frog but with square spots in rows. Their belly is bright yellow or orange. Their call is a low, snoring sound. They live in cold, clear streams.
Spring Peeper
Tiny (1 inch) with an X-shaped cross on its back. Color varies from tan to gray. Their high-pitched peeping call is one of the first signs of spring. They breed in vernal pools.
Gray Treefrog
Small (1.5-2 inches) with warty skin and large toe pads. They can change color from gray to green. Their call is a short, musical trill. Found in forests near water.
American Toad
Warty skin, brown or gray, with a white belly. They have two large bumps behind their eyes (parotoid glands). Their call is a long, high-pitched trill lasting 10-30 seconds. Common in gardens and fields.
Fowler’s Toad
Similar to American Toad but smaller with three or more warts per dark spot. Their call is a short, nasal “waaaah.” They prefer sandy areas.
Eastern Spadefoot
Rare in Maryland. They have smooth skin, vertical pupils, and a black spade on each hind foot. Their call is a short, explosive “quack.” They breed in temporary pools after heavy rain.
How To Identify Frogs By Call
Listening is often easier than looking. Many frogs are shy and hide. Learn these common calls:
- Spring Peeper: High-pitched peep, repeated every second
- American Toad: Long, musical trill
- Gray Treefrog: Short, melodic trill
- Green Frog: Single “gunk” sound
- Bullfrog: Deep “jug-o-rum”
- Leopard Frog: Low snore with clicks
Use a phone app like iNaturalist or FrogID to record and compare. Practice at night near ponds.
Best Places To Find Frogs In Maryland
Frogs need water to breed. Look in these habitats:
- Vernal pools: Temporary spring pools. Great for Spring Peepers and Wood Frogs.
- Ponds and lakes: Bullfrogs, Green Frogs, and Leopard Frogs.
- Marshes: Pickerel Frogs and Green Frogs.
- Forests: Gray Treefrogs and American Toads.
- Streams: Pickerel Frogs and occasionally Spadefoots.
When To Look
- Spring (March-May): Breeding season. Most active and vocal.
- Summer (June-August): Some species call, but less frequent.
- Fall (September-October): Young frogs disperse. Harder to find.
- Winter: Most hibernate. Only a few species are active.
Step-By-Step Identification Process
Follow these steps to identify any frog you find:
- Observe the habitat. Is it a pond, stream, or forest? This narrows possibilities.
- Note the size. Compare to common objects (a quarter, a soda can).
- Check skin texture. Smooth or warty? Moist or dry?
- Look at color and pattern. Solid, spotted, striped? Belly color?
- Listen for calls. Record if possible.
- Check toe pads. Large pads mean tree frog. Small pads mean true frog or toad.
- Use a field guide or app. Compare your observations.
Common Mistakes In Frog Identification
- Mistaking toads for frogs: Toads have warty, dry skin; frogs are smooth and moist.
- Confusing Green Frogs with Bullfrogs: Green Frogs are smaller and have a ridge down each side.
- Thinking all spotted frogs are Leopard Frogs: Pickerel Frogs have square spots in rows.
- Ignoring calls: Many species look alike but sound different.
Tools And Resources For Identification
You don’t need expensive gear. These help:
- Field guides: “Peterson Field Guide to Reptiles and Amphibians” or “The Frogs and Toads of North America.”
- Phone apps: iNaturalist, FrogID, Audubon Frog Guide.
- Online resources: Maryland Department of Natural Resources website, FrogWatch USA.
- Local groups: Join a herpetology club or attend a frog walk.
Conservation And Ethical Viewing
Frogs are sensitive. Follow these rules:
- Do not touch frogs with dry hands. Oils harm their skin.
- Do not remove frogs from the wild.
- Stay quiet and move slowly.
- Report rare species to the Maryland DNR.
- Protect wetlands from pollution and development.
Seasonal Guide To Maryland Frogs
Spring (March-May)
This is the best time. Wood Frogs, Spring Peepers, and American Toads breed in vernal pools. You’ll hear choruses at night. Look for egg masses in shallow water.
Summer (June-August)
Green Frogs and Bullfrogs are active. Gray Treefrogs call from trees. Leopard Frogs are near grassy ponds. Toads are in gardens.
Fall (September-October)
Young frogs leave water. You’ll see tiny frogs on land. Calls are rare. Some species, like Spring Peepers, may call on warm days.
Winter (November-February)
Most frogs hibernate in mud or under logs. A few, like Spring Peepers, can survive freezing. You won’t see many.
Frog Identification By Region In Maryland
Western Maryland (Mountains)
Cool streams and forests. Look for Pickerel Frogs, Spring Peepers, and Gray Treefrogs. Fewer Bullfrogs.
Central Maryland (Piedmont)
Mix of ponds and farms. Common: Green Frogs, Leopard Frogs, American Toads. Good for beginners.
Eastern Shore (Coastal Plain)
Wetlands and marshes. Many species: Bullfrogs, Green Frogs, Fowler’s Toads. Rare: Eastern Spadefoot.
Southern Maryland
Forests and tidal marshes. Gray Treefrogs, Spring Peepers, and Pickerel Frogs. Good for night walks.
How To Photograph Frogs For Identification
- Use a camera or phone with good zoom.
- Approach slowly from the side, not above.
- Take multiple angles: side, top, belly.
- Include a size reference (coin, ruler).
- Record the call on video.
- Note the date, time, and location.
Frog Calls Quick Reference
| Species | Call Description | When Heard |
|---|---|---|
| Spring Peeper | High-pitched peep | March-April |
| American Toad | Long musical trill | April-May |
| Gray Treefrog | Short melodic trill | May-July |
| Green Frog | Single “gunk” | May-August |
| Bullfrog | Deep “jug-o-rum” | June-August |
| Leopard Frog | Low snore + clicks | April-June |
Frequently Asked Questions
What is the most common frog in Maryland?
The Green Frog is very common. You’ll find it in most ponds and streams. The American Toad is also widespread.
How can I tell a frog from a toad?
Frogs have smooth, moist skin and long legs for jumping. Toads have warty, dry skin and shorter legs. Toads also have parotoid glands behind their eyes.
Are there poisonous frogs in Maryland?
No. No native frogs are dangerously poisonous. Toads have toxins that can irritate skin or harm pets if eaten. But they are not deadly to humans.
When is the best time to hear frog calls?
Spring evenings, especially after rain. March through May is peak calling season. Some species call in summer too.
What should I do if I find a rare frog?
Take a photo and note the location. Report it to the Maryland Department of Natural Resources. Do not disturb the animal or its habitat.
Final Tips For Success
Start with common species. Learn their calls first. Then move to rarer ones. Practice in your backyard or local park. Join a frog walk with experts. Keep a journal of what you see and hear.
Remember, patience is key. Frogs are most active at dusk and dawn. Move slowly and listen carefully. With time, you’ll identify frogs like a pro.
This Maryland Frog Identification Guide covers the basics. Use it as a starting point. The more you practice, the better you’ll get. Happy frog watching!