Non-Native Species

One of the largest threats to natural habitats, world-wide, is the biological invasion of non-native plants and animals. Ecosystems and the habitats within them have a natural balance that can be greatly altered by the introduction of non-native species. Billions are spent annually to eradicate invasive non-native species such as zebra mussels, Brazilian pepper, melaleuca and hundreds of other introduced plants and animals.

In Florida alone it is estimated that there are over 900 established non-native plant and animal species. Not all of these species pose a major issue, but several can create ecological devastation. Learnn more about two of the most impactful on-native species below!

 

Burmese python with its tongue out

NPS Image

Burmese Python

In recent years, snakes from around the world have been turning up in and around Big Cypress National Preserve. Burmese pythons, one of the largest snake species on earth, are now known to be breeding in the Preserve and spreading throughout south Florida.

Burmese pythons can reach lengths of 19 feet, but usually average much closer to 12 feet. The snake's skin coloration is generally a pattern of large reddish brown blotches outlined in cream. These snakes are very adaptable and can live in a wide variety of habitats including grasslands, marshes, swamps, and woodlands as long as there is a permanent water source. They have a diverse diet that includes birds, mammals, and reptiles.

These reptiles are native to northeastern India east through southern China, Southeast Asia and the Malay Peninsula. They likely made it to Big Cypress and the rest of south Florida when pet snakes escaped from their homes or were released into the wild when their owners could no longer care for them. The first python was observed in the Everglades in 1979, but no more were seen until 1995. Since then, the number of observations has increased dramatically.

The effects of the introduction of these snakes appear to be devastating to many native animals. Pythons are very effective at killing many different types of animals and mammals in particular have no fear of the large snakes because they have never had to share a habitat with them before. A study published in December 2011, reports that sightings of rabbits, foxes, raccoons, white-tailed deer, and opossums have all declined by more than 90 percent since the time when python sightings have increased. The snakes can also eat a lot of birds, including endangered wood storks. More than 25 percent of captured snakes contain birds in their stomachs.

It is currently unclear what, if anything, can realistically be done to get rid of the pythons. They are secretive, very hard to find, and live in areas (the Everglades, Big Cypress, and other state and federal lands) with large expanses of remote areas that are hard to access.

If nothing else, these pythons can serve as a painful reminder of just how dangerous invasive species can be. Any sort of non-native plant or animal has the potential to cause ecological problems if released into the wild. When it comes to picking a new pet or planting your gardens, consider buying native plants and animals!

That is why teams of biologists are working hard everyday to track, observe, and
ultimately euthanize these animals. Researchers capture and tag ‘scout snakes’ that fall within certain research parameters. These snakes are tracked every week so that data can be analyzed. Teams are trying to determine the pythons life span, their eating habits, in addition to how much they move around and other basic life questions!

 

Four people walk through vegetation covered by 'Old World Climbing Fern'

NPS Image

'Old World Climbing Fern'

Lygodium microphyllum, or Old World Climbing Fern is native to tropical African and Asian countries but was brought to South Florida as an ornamental plant. Old World climbing fern can grow in bald cypress stands, pine flatwoods, wet prairies, saw grass marshes, mangrove communities and Everglades tree islands. This is a type of fern that will grow over existing trees and plants until they are completely blanketed by the lygodium.This fern is able to grow faster than most native plants, and will out-compete them for available nutrients and sunlight. Some areas are so completely blanketed by the fern that it is not possible to see trees and other vegetation beneath the fern canopy.

The fern poses management problems for both wildfires and prescribed burns because it can serve as a fire ladder that carries fire into the tree canopy that kills native trees. Also, portions of burning fern can frequently break free and spread fire to surrounding areas.

In order to combat this extremely-invasive plant, botanists from Big Cypress have developed cutting-edge, spot-spray techniques that allows scientists to directly spray specific herbicides on to pre-determined patches of Lygodium without causing harm to the surrounding native plants. This program takes immense coordination with NPS staff, local and state agencies, and contractors to effectively manage Lygodium microphyllum, and other invasive plant species!