It is not illegal to kill a praying mantis in PA. No Pennsylvania statute and no federal law protects praying mantises, and the widely repeated $50 fine for killing one has never existed. You can kill a mantis in your yard without breaking any rule.
Why No Pennsylvania Law Covers Praying Mantises
Pennsylvania’s Game and Wildlife Code, Title 34, defines “wildlife” as wild birds and wild mammals, along with their parts, products, eggs, and offspring. Insects aren’t in that definition.1Pennsylvania General Assembly. Title 34 – Game The Pennsylvania Game Commission enforces Title 34 and regulates game animals, furbearers, and birds.2Pennsylvania Game Commission. Seasons and Bag Limits The Pennsylvania Fish and Boat Commission handles fish, reptiles, amphibians, and aquatic invertebrates.3Pennsylvania Fish and Boat Commission. Threatened and Endangered Species Neither agency has jurisdiction over terrestrial insects.
The federal Endangered Species Act can protect insects, and it does protect a few, including the rusty patched bumble bee and the Karner blue butterfly. No praying mantis species has ever been listed as federally endangered or threatened.
Pennsylvania’s Natural Heritage Program tracks some rare insects for conservation monitoring, mostly butterflies and moths, but tracking is not legal protection, and no tracked insect currently holds state endangered or threatened status.4Pennsylvania Natural Heritage Program. Environmental Review List Praying mantises aren’t on any list in any form.
Where the $50 Fine Myth Came From
The $50 fine story has been circulating since the 1950s, and no one has traced it to an actual source. The most common theory ties it to the insect’s folded-forelimb posture, which gave it an almost sacred quality in popular imagination, combined with its visible role eating pests in gardens. Something that distinctive and useful, people assumed, must be protected by law. The assumption got passed from parent to child for decades and hardened into “common knowledge.”
The number itself is the giveaway. Real penalties for killing a protected species in Pennsylvania run into the thousands of dollars, not fifty. Even Connecticut, which named the praying mantis its official state insect, has no law against killing one.5Justia Law. Connecticut General Statutes 3-109b – State Insect State insect designations are honorary.
Native and Invasive Mantises in Pennsylvania
If you’re deciding whether to kill a mantis you’ve found, species matters more than the law does. Most mantises in Pennsylvania aren’t native, and the common ones cause real harm to local insect populations.
- The Chinese mantis is the largest in North America, up to five inches long, slender, brown to green. Its egg case is a puffy, cube-shaped, foamy-textured, straw-brown lump.
- The European mantis runs about four inches, usually greener, with a bull’s-eye marking under the foreleg. Its egg case is elongated and pale brown, with no striping.
- The Carolina mantis is the only native species and the smallest at about three inches, ranging from green to dusty brown to grey. Its egg case is elongated and smooth, with alternating lighter and darker brown stripes.
The Chinese mantis is the biggest problem. It’s a non-selective predator and has been documented attacking beneficial pollinators, hummingbirds, and other small animals along with pest insects, and it can displace the smaller native Carolina mantis through competition. Garden stores sell Chinese mantis egg cases as “natural pest control,” which keeps spreading the invasive population.
Learning to tell the native Carolina mantis from the two invasive species by size and egg case shape is more useful than worrying about any legal consequence. Removing invasive mantis egg cases before they hatch in spring is one thing a gardener can do, and it’s entirely legal.