Discover The 7 Largest Animals In Pennsylvania, and Where You’ll Find Them

Written by Kyle Glatz
Updated: June 6, 2023
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Pennsylvania is an interesting state that has urban areas in Philadelphia and Pittsburgh at either end along with expanses of wild areas between them. In those rural places, it’s possible to find all types of interesting creatures. That includes some very large animals, the subject of this article. Take a look at seven of the largest animals in Pennsylvania and learn where they live and how big they get.  

What Are The 7 Largest Animals in Pennsylvania?

We’re not going to just list the seven biggest animals that we can find in Pennsylvania. Instead, we’ll focus on one representative from several different groups of animals in the state. These include birds, mammals, fish, insects, and more. By the time we’re finished looking at the largest animals in Pennsylvania, you’ll have a good understanding of several big creatures in this state.

1. Flathead Catfish

Flathead Catfish

The flathead catfish is one of the largest fish in Pennsylvania.


Scientific NameSizeLocation
Pylodictis olivaris2.5-4.2 feet long, over 5 feet in some areasFound in Lake Erie and Ohio River tributaries in the west and south of the state.

The flathead catfish is the largest freshwater fish in Pennsylvania. That holds true in terms of the biggest fish caught in the state as well as the one with the potential to get the largest. This fish is known for its shovel-shaped, flat head along with its incredible size.

The heaviest one ever caught in the state weighed 57 pounds and measured almost four feet long! These aren’t even the largest ones in the U.S.! You can find them in Lake Erie along with various tributaries of the Ohio River in the south and western portions of the state.

2. Mute Swan

mute swan in calm water

The mute swan is found in the southwestern part of Pennsylvania.


Scientific NameSizeLocation
Cygnus olor6-7.9 feet in wingspanPrimarily found in eastern Pennsylvania and sometimes in the far southwestern reaches of the state.

The mute swan is a massive waterfowl, and it’s one of the largest animals in Pennsylvania. You’ll often find them around the eastern part of Pennsylvania by the Delaware River and various marshy lands around it, but they can also nest in the southwest part of the state.

These massive swans have a white body, orange bill, and some black coloration on their nostrils and near their eyes. If you encounter one, keep your distance. They will attack people that come near their nests. Since they have a wingspan over 7 feet long and measure over 5 feet long in body length, they are imposing and not animals worth picking a fight with!

3. Elk

Bull Elk in the Fall Rut

Elks are among the largest animals in Pennsylvania.

©Tom Tietz/

Scientific NameSizeLocation
Cervus canadensis          6.9-8 feet longFound in forested, mountainous regions, especially in central northern PA.

The elk is chief among the largest animals in Pennsylvania, even bigger than the black bears that share their range. An adult elk can stand 5 feet tall at the shoulders and regularly weigh over 700 pounds. Some of them can weigh over 1,000 pounds!

These creatures may be found in the forested areas of Pennsylvania, especially in the central northern portion of the state. You have a good chance to find them in Elk, Clinton, Clearfield, Potter, and Cameron counties, but try not to get too close. They can be very dangerous to people.   

4. Eastern Black Rat Snake

Black Rat snake in Virginia's Caledon State Park. These are large, non-venomous snakes between 3.5 and 7 feet (one and two meters) long.

Eastern black rat snakes are large, non-venomous snakes between 3.5 and 7 feet long.


Scientific NameSizeLocation
Pantherophis alleghaniensis6-7 feet longFound mostly throughout the state in farmlands, meadows, and even suburban areas. Prefers to hide in the brush or beneath debris.

The eastern black rat snake may not be as long as its western cousin, but it can still reach six feet long or more. That makes it the longest snake in Pennsylvania. Don’t worry if you encounter this snake, though. It’s not venomous and it doesn’t go out of its way to attack people.

As its name suggests, this snake prefers to hunt rodents. They are present throughout the state, but it’s easiest to find them in farmlands, meadows, wooded areas, and even some suburbs. They like to hide in brush, under logs, and in other debris.  

5. Eastern Hellbender

An Eastern Hellbender with the frills of skin along the sides of the body that allow it to take in oxygen, clearly visible.

Eastern hellbenders can be up to 2.5 feet long.


Scientific NameSizeLocation
Cryptobranchus alleganiensis1-2.5 feet longLocated in the Allegheny Mountains and waters in the watershed of the Susquehanna and Ohio Rivers.

The eastern hellbender is not all that scary for its name. This giant aquatic salamander is found in waters in the Allegheny Mountains as well as those in the watershed for the Ohio and Susquehanna Rivers. The hellbender is the state’s official amphibian.

Eastern hellbenders live under rocks, logs, and other debris in the water where they can stay out of sight. They’re mostly nocturnal and have four small legs, a brown, black, or olive body, and small, wide-spaced eyes. They can grow upwards of 2.5 feet long at their largest!

6. Giant Swallowtail Butterfly

giant swallowtail butterfly

With a wingspan of 6 inches, the giant swallowtail butterfly is one of the largest insects in Pennsylvania.

©Kevin Collison/

Scientific NameSizeLocation
Papilio cresphontes4-6 inches in wingspanOften found in fields, near wooded areas, and meadows as they pollinate various flowers.

The giant swallowtail butterfly is one of the largest insects you’ll find in the U.S. by size alone. This creature has a wingspan that can reach 6 inches wide! They are known for having beautiful black wings along with yellow patterns on the bottoms of their forewings and hindwings.

These insects can be found in many parts of the state, often feeding on nectar from various flowers. They are gorgeous to behold and usually seen in meadows, open fields near water, and wooded areas.

7. Carolina Wolf Spider

Largest Wolf Spider - Carolina Wolf Spider

The Carolina

wolf spider

is the largest spider in Pennsylvania.

©Will E. Davis/

Scientific NameSizeLocation
Hogna carolinensis2-4 inches in legspanOften found in forests, wooded areas near meadows, and near and inside of suburban and rural homes.

The Carolina wolf spider is the largest spider in Pennsylvania, having a four-inch legspan. This arachnid is nearly black, dark brown, or gray with various patterns including a light line that runs down the middle of its cephalothorax. They’re easy to identify if you can get them to stay still, which is not something they often do.

These spiders are hunters that may ambush their prey from rocks, under debris, or simply hunt them down. They’re found in forests, meadows, and less-used portions of homes, of course. Although they aren’t venomous, their bite is hardly pleasant.  

Now that we have uncovered the largest animals in Pennsylvania, you’ll know what to look for when you visit the state. This place is home to large deer, arachnids, and even birds. Oftentimes, it’s wise to look at these creatures but not approach them.

Their size makes several of the animals on this list dangerous. Lastly, other large, dangerous animals live in Pennsylvania, including black bears. Always take some time to review the potentially dangerous animals in any place you plan on visiting!

Summary of the 7 Largest Animals in Pennsylvania

Common NameScientific NameSizeLocation
Flathead CatfishPylodictis olivaris2.5-4.2 feet long, over 5 feet in some areasLake Erie and Ohio River tributaries in the west and south.
Mute SwanCygnus olor6-7.9 feet in wingspanEastern Pennsylvania; sometimes in the state’s southwest.
ElkCervus canadensis 6.9-8 feet longForested and mountainous areas, especially in central and northern Pennsylvania.
Eastern Black Rat SnakePantherophis alleghaniensis6-7 feet longThroughout the state in farmlands, meadows, and suburban areas in the brush or debris.
Eastern HellbenderCryptobranchus alleganiensis1-2.5 feet longAllegheny Mountains, and watershed of the Susquehanna and Ohio Rivers.
Giant Swallowtail ButterflyPapilio cresphontes4-6 inches in wingspanFields, near wooded areas, and meadows.
Carolina Wolf SpiderHogna carolinensis2-4 inches in legspanForests, wooded areas, and houses.

The photo featured at the top of this post is © Cody Linde/

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About the Author

Kyle Glatz is a writer at A-Z-Animals where his primary focus is on geography and mammals. Kyle has been writing for researching and writing about animals and numerous other topics for 10 years, and he holds a Bachelor's Degree in English and Education from Rowan University. A resident of New Jersey, Kyle enjoys reading, writing, and playing video games.

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  1. Pennsylvania Game Commission (1970) elk inhabit portions of,Commission between 1913 and 1926
  2. University of Florida, Available here:,the%20entire%20state%20of%20Florida