17 INVASIVE Animals found in Louisiana! (2025)

What kinds of invasive species can you find in Louisiana?

Animals that are not native can cause many problems. They put a lot of pressure on native species as they compete for food, territories, and nesting areas.

Below, you will learn about an array of different invasive creatures, along with the myriad of problems they cause!

17 Invasive Animals Found in Louisiana:

Just a quick note: you won’t find any insects or fish below. Those articles are coming soon! 🙂


#1. Rock Pigeon

  • Columba livia

Types of invasive animals in Louisiana

These invasive birds are common in Louisiana but are almost exclusively found in urban areas. Rock Pigeons are what everyone refers to as “pigeons.” You have probably seen them gathering in huge flocks in city parks, hoping to get tossed some birdseed or leftover food.

The typical pigeon has a gray back, a blue-gray head, and two black wing bars. In addition, look for a green and purple iridescence around their necks!

Rock Pigeon Range Map

pigeon range map

Love them or hate them, Rock Pigeons have been associated with humans for a long time! Some Egyptian hieroglyphics suggest that people started domesticating them over 5,000 years ago. But, interestingly, scientists aren’t even sure where their original range occurs!


#2. Domestic Cat

  • Felis catus

Types of invasive animals in Louisiana

  • Can be a wide range of colors, sizes, shapes, and fur lengths.
  • Selected mutations observed in many pet cats, such as folded ears, munchkin legs, or flattened faces, are not commonly seen among domestic cats successfully living feral.

Sadly, domestic cats are very damaging to the ecosystems in Louisiana where they are introduced. It has only been in the last century or so that cats have become pets that stay indoors.

It is estimated that these invasive animals kill over 1 billion birds and 6 billion other small animals annually. Feral cats that live and breed away from the care of humans are the most prolific hunters.

As you can imagine, this issue is hotly debated due to the love people have for their pet cats. Some experts think that trap-neuter-return programs are key to curbing the problem of feral cats. At the same time, others are huge proponents of NEVER letting your cat outside.


#3. European Starling

  • Sturnus vulgaris

Types of invasive animals in Louisiana

  • They are about the size of an American Robin. Their plumage is black and appears to be shiny.
  • Breeding adults are darker black and have a green-purple tint.
  • In winter, starlings lose their glossiness, their beaks become darker, and they develop white spots over their bodies.

Despite being common, European Starlings are an invasive species in Louisiana.

Back in 1890, one hundred starlings were brought over from Europe and released in New York City’s Central Park. The man responsible (Eugene Schieffelin) had a mission to introduce all of the birds mentioned in Shakespeare’s plays to North America.

European Starling Range Map

starling range map

The rest is history as starlings easily conquered the continent, along the way out-competing many of our beautiful native birds. Their ability to adapt to human development and eat almost anything is uncanny to virtually no other species.

Here’s something amazing about these non-native birds:

It’s the magical way they travel in flocks, called murmurations. Check out the video below because it’s mesmerizing. 🙂

YouTube video

#4. Wild Boar

  • Sus scrofa

Types of Invasive Species in Louisiana

  • Adults range from 5 to 8 feet in length and weigh between 145 and 600 pounds.
  • Their thick, coarse hair ranges in color from black to reddish-brown.
  • Males have large canines that protrude from the mouths of adult males.

Wild Boars are invasive mammals in Louisiana, as they were introduced from overseas. Their population has exploded in the last 50-100 years, leading wildlife departments to implement population control programs.

Because of their aggressive nature and lack of fear, Wild Boars can be dangerous to livestock, humans, and pets. If you have a Wild Boar on your property or see one while you’re out and about, call your local animal control office for advice. Don’t try to approach this unpredictable animal!

They are omnivores, and what they eat varies with season and location. Wild Boars consume large amounts of plant matter, including fruits, nuts, roots, herbaceous plants, and crops. Their voracious appetite can be very detrimental to an ecosystem, causing a loss of plant diversity and extensive soil erosion.


#5. Eurasian Collared-Dove

  • Streptopelia decaocto

Types of Invasive Species in Louisiana

  • A mostly sandy gray bird with a long, square-tipped tail.
  • As the name suggests, look for a black collar on the back of the neck.

Interestingly, these birds are invasive to Louisiana.

Unfortunately, somebody introduced Eurasian Collared-Doves to the Bahamas in the 1970s, and since then, they have rapidly spread. In fact, their population is still spreading!

Eurasian Collared-Dove Range Map

Eurasian collared dove range map

One of the reasons these birds colonized here so quickly is due to their comfort level with humans. They have thrived being around bird feeders and in urban and suburban areas. It’s common to see them on the ground or platform feeders eating grains and seeds.

How do you tell them apart from Mourning Doves?

At first glance, Eurasian Collared-Doves look very similar to the native Mourning Dove. Here’s how to tell them apart:

Types of Invasive Species in Louisiana

  • Mourning Doves are smaller and have black dots on their wings.
  • Eurasian Collared-Doves are larger and have a black crescent around their neck.

#6. House Sparrow

  • Passer domesticus

Types of Invasive Species in Louisiana

House Sparrows are an invasive species that originated from the Middle East. But now they are one of the most widespread birds in Louisiana (and the world)!

House Sparrows owe their success to their ability to adapt and live near humans. Because of this, they are almost always found in urban and suburban areas.

Range Map – House Sparrow

house sparrow range map

House Sparrows can be heard across the entire planet. Pay attention the next time you’re watching the news in another country. Listen for a simple song that includes lots of “cheep” notes.

YouTube video

#7. House Mouse

  • Mus musculus

House Mouse

  • The tails are hairless and can be as long as their bodies.
  • House Mice are smaller and lighter built than rats.
  • They usually have light brown fur and large round ears compared to their heads, which give them a cute look.

These invasive rodents originated in Asia but can now be found in Louisiana. House Mice arrived in North America on ships in the 1600s and quickly multiplied.

Mice have dispersed across the planet incredibly successfully, second perhaps only to humans. The biggest key to their success is their ability to adapt their behavior quickly and breed prolifically.

House Mouse Range Map

Native range (dark red). Introduced (light red) Attribution: Osado, Public domain, via Wikimedia Commons
Native range (dark red). Introduced (light red) Attribution: Osado, Public domain, via Wikimedia Commons

Salmonella and parasites are the most prevalent illnesses that mice transmit to humans by contaminating food. However, this risk has been greatly reduced through modern food management techniques in the USA.

House Mice also greatly impact the ecosystems that they invade. They are omnivorous and will devour plants and target animal species that have not adapted to fighting them off.

Fascinatingly, House Mice also cause the decline of native species by bolstering the health of predators through seasons when other prey would have been hard to find. By becoming prey themselves, the mice inflate the populations of predators year-round.


#8. Brown Rat

  • Rattus norvegicus

Look for Brown Rats anywhere people are living, particularly in urban environments. They’re best known for living in sewer tunnels and subway systems, scavenging food from the trash.

Believe it or not, this invasive species isn’t native to Louisiana. It’s thought to have originated in China and Mongolia.

It’s a misconception that Brown Rats spread bubonic plague. In actuality, it’s more commonly spread through ground squirrels! Regardless, they can transmit infections of many kinds, as their blood can carry several diseases.


#9. Greylag Goose

  • Anser anser

  • Greylag Geese are a soft, warm gray-brown.
  • Their feathers are rimmed with narrow white edges, which gives them a delicate barred pattern over their wings, chest, and sides.
  • The legs are pink, while their bills are bright orange.

Greylag Geese are NOT native to Louisiana!

These birds are found naturally across Europe and Asia, where they are very common and have a huge natural range.

Interestingly, Greylag Geese gave rise to almost all common domesticated goose breeds.

Domesticated Greylag Geese can commonly be seen on farms, estates, and in zoological collections. But, occasionally, escaped birds may flourish as feral populations.

Greylag Geese are very social animals. They will almost always be found in flocks, ranging from a few birds to thousands of animals. When flying, flocks adopt the classic V-shape flight formation. Play the video to see them in action!

YouTube video

#10. Black Rat

  • Rattus rattus

Interestingly, the Black Rat is an invasive species in Louisiana.

It’s thought it came from India and was transported to North America on cargo ships. They are now so widespread that it’s considered “naturalized.”

Black Rats are a pest in the agricultural market because they feed on various crops. Like other rodents, they can carry pathogens in their bodies. While they may not appear sick, they can spread infections like toxoplasmosis, typhus, and bubonic plague.

The Brown Rat has taken over many areas where the Black Rat was once the dominant species. Black Rats are slightly smaller and reproduce less often, two reasons this species isn’t as widespread as Brown Rats.


#11. Nutria

  • Myocastor coypus

Nutria

  • Has two very large, yellowed incisor teeth.
  • Has a long, thin tail with no hair on it.

Nutria look like a combination of a beaver and a muskrat. They live near waterways in burrows, and their native range is tropical and temperate South America.

Nutria were intentionally introduced to North America in 1889 by fur farmers. Over the years, many individuals escaped and eventually established a wild population.

Nutria Range Map

"Native

These invasive animals cause many problems in Louisiana!

Because Nutria devour so many plants daily, they cause irreparable damage to wetlands and marshes. Their prolific eating habits also cause direct conflict with humans. They are known to destroy crops such as rice, corn, sugar, and many others.

The burrowing behavior of Nutria also harms the ecosystem. The burrows weaken the structure of the ground they dig into. Nutria burrows inadvertently cause damage to human structures, such as roads, dams, and flood defenses.

Lastly, Nutria carry several diseases that can make humans ill. Tuberculosis, septicemia, and various parasites can pass from these rodents to humans. The presence of Nutria in a waterway can make swimming in or drinking the water dangerous.


#12. Mediterranean House Gecko

  • Hemidactylus turcicus

  • 1.5 to 2.5 inches long.
  • The pupils are vertical, and the eyes are large and round with immovable eyelids.
  • This species has two color phases for camouflage.
    • Pale phase: the coloring is light pink to pale yellow or white with brown or gray blotches.
    • Dark phase: the coloring darkens to gray or brown, obscuring the blotches on the back.

You might be surprised that this gecko is NOT native to Louisiana! The Mediterranean House Gecko was introduced via imported plants carrying their egg clutches. They’re adaptable to so many environments that their population quickly outpaced any of our native geckos!

Mediterranean House Geckos are nocturnal, but this won’t stop you from being able to find them. They’re considered an “urbanized” species, which means they’re just as happy to live inside your house as they are in the wild!

Virginia Herpetological Society

In addition to being comfortable around humans, Mediterranean House Geckos are some of the most vocal lizards around. The mating call of males is a series of clicks, and they frequently make a squeaking noise if threatened.


#13. Brown Anole

  • Anolis sagrei

  • 5 to 8.5 inches long.
  • The coloring is brown, sometimes with yellow spots – this species is never green.
  • The dewlap is red-orange with yellow or white borders.

Brown Anoles are a widely introduced lizard in Louisiana!

Look for them on tree trunks and rocks near the ground or in open grassy areas.

The Brown Anoles’ native range is Cuba, the Bahamas, and Little Cayman Island. Their population and range exploded when they were introduced in shipments of cultivated plants in the 1970s.

They established themselves so quickly that native Green Anoles had to change their behavior to survive. Because Brown Anoles eat Green Anoles and compete with them for food and territory, they’ve taken over ground habitats and pushed Green Anoles up into the trees.


#14. Scaly-breasted Munia

  • Lonchura punctulata

Scaly-breasted munia

  • Males and females look very similar, though males have darker throats.
  • Look for brown fringes to their white chest feathers, giving them a scaled appearance.
  • They have short, triangular beaks.

Scaly-breasted Munia are small, seed-eating birds in the finch family. They are native to the tropical regions of South and Southeast Asia.

Their social behavior and charming vocalizations have made them popular historically as caged pet birds. The Scaly-breasted Munia was intentionally imported to the USA to be sold as an exotic pet.

YouTube video

Escapees have been spotted establishing feral colonies since the 1980s but were likely present much earlier than that. Scaly-breasted Munias can now be spotted in California, Texas, Mississippi, Alabama, and Florida.

These invasive birds are very gregarious, forming large flocks of hundreds of birds. Consequently, they can cause extensive damage to crops when flocks target farms. Furthermore, Scaly-breasted Munia can outcompete native species for resources.


#15. Greenhouse Frog

  • Eleutherodactylus planirostris

greenhouse frog

  • Adults are tiny and measure only 17 to 31 mm (0.67 to 1.22 in) in length.
  • Olive-brown coloration.
  • Some adults have two darker stripes running down their backs, while others have dark blotching.

This frog species is NOT native to Louisiana.

Greenhouse Frogs are from Cuba and other islands in the West Indies. But they have made their way to the United States and now are relatively common living around people.

But these frogs are hard to find! They are small, nocturnal, and mostly live in moist leaf litter. The best time to find one is on a warm, rainy night during summer.

The eggs and tadpole stages of Greenhouse Frogs are unique. First, instead of laying a giant mass of eggs like other frogs, they lay them singly in damp locations, buried under debris or logs. Second, the tadpole stage happens entirely while in the egg! So, fully developed juvenile frogs hatch directly from the eggs and are only about 5 mm long.


#16. Monk Parakeet

  • Myiopsitta monachus

Monk parakeet

  • Males and females look almost identical, though females tend to be a little smaller.
  • Bright green plumage with blue wing tips.
  • Large orange beaks and paler chests.

Monk Parakeets are a species of parrot originating in South America. Their ability to mimic sounds and words, combined with their social nature and beautiful plumage, has made them popular pets around the globe.

In the 1950s and 1960s, thousands of Monk Parakeets were imported as exotic pets for sale in the USA. Many of them escaped or were intentionally released over time.

These invasive birds build prolific nests in Louisiana.

Their nest-building has caused direct conflict with humans by damaging homes and buildings. They are gregarious birds and often build huge, chambered nests that house multiple families.

YouTube video

For warmth, they have taken to building these incredible nests around heating elements, such as on electrical pylons and power stations.

This behavior has caused many issues for the people who rely on the electrical grid and the companies that maintain them. The nests can short-circuit the electrical facility, become a fire hazard, and damage equipment. Removing the nests is a very dangerous job and a temporary fix as the parakeets quickly rebuild.

Monk Parakeets do not seem to have a strong negative impact on native fauna. They may increase competition for food and can become agricultural pests when they feed on fruit crops. However, their prolific nest-building behavior actually leads them to act as ecosystem engineers and potentially increase nesting opportunities for other bird species. They feed and nest alongside native birds with little conflict (Cristóbal Briceño et al.)


#17. Brahminy Blindsnake

  • Indotyphlops braminus

  • Adults are small, only 5.1-10.2 cm (2-4 in) long.
  • Their coloring varies; charcoal gray, light yellow-beige, silver-gray, purplish, and white are common.
  • The body shape is worm-like, and they are easily mistaken for earthworms.

It is really hard to see this invasive snake in Florida.

That’s because they spend almost all their time underground in ant and termite nests and live under logs, moist leaves, and stones. Look for them in urban gardens and moist forests.

The Brahminy Blindsnake, as its name suggests, is almost completely blind. It has small, translucent eyes that can detect light but not form images. This snake species is not native to Florida. Instead, it arrived here by being transported in the soil of potted plants, which has earned them the nickname “Flowerpot Snake.”

When distressed or attacked, the Brahminy Blindsnake will try to escape underground. If touched, it might press its tail on the attacker and release a smelly musk. Despite its rather creepy appearance, this snake is completely harmless to humans.


Learn more about other animals in Louisiana!


Which of these invasive species have you seen in Louisiana?

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