Non-native species invade Florida’s Everglades
Located in the southern portion of the U.S. state of Florida is a vast subtropical wetlands area known as the Everglades. It is a complex ecosystem of marshes, cypress and mangrove swamps, tropical hardwoods, pine and coastal marine environment. Humans have turned around half of the Everglades into farmland or urban areas, while 25% of the original area remains protected as Everglades National Park, the third largest national park in the United States. It is home to a whopping 36 threatened species. The “threatened” status is bestowed upon species that fall into three categories: vulnerable, endangered and critically endangered by the World Conservation Union (IUCN). Among threatened species in the Everglades are the Florida panther, the West Indian manatee and the American crocodile. Many of these animals live in parts of the Everglades that are not part of the National park and are therefore not well protected. Some, like the Florida panther, require large hunting grounds, which are being progressively encroached upon by housing and urban developments. Contrastingly, Florida’s once threatened alligator population has experienced a strong revival in the past 30 years and was declared ‘fully recovered’ in 1987 by the Fish and Wildlife Service.
But it is not only human driven development that threatens the ecosystems in the Everglades, but something far more surprising: our pets. It is estimated that as many as 150,000 Burmese pythons are living in the Everglades and may be wreaking havoc upon the indigenous wildlife. Bought as pets and released into the wild when owners decide that they’ve grown too large to keep and feed, the giant snakes thrive virtually predator-free in the Florida wetlands. They also reproduce quickly and can lay from 50-100 eggs in a single clutch. One of the largest snakes in the world, a mature python can eat an animal as large as a deer or even a fully-grown alligator.
Another bothersome invader of the Everglades is the Nile monitor lizard, examples of which have caused problems basking on airport runways. Monitor lizards can grow over six feet long (two meters) and are known to gorge themselves on the frogs and in the nesting areas of local wildlife. Both pythons and monitors eat the eggs of native species and are actively caught and trapped by wildlife officials. Also a nuisance are Florida’s feral pigs, which – consummate omnivores that they are – eat virtually everything. The pigs are thought to have been living in the wilds of the state since Spanish colonists first arrived with domesticated livestock.
Other introduced species living in the Everglades include migrating coyotes, the African Sacred Ibis (once venerated in ancient Egypt) and – perhaps the most destructive of all – the common house cat, which is one of the most successful small predators in the animal kingdom. You must have known your cat’s sense of self-importance came from somewhere.
By Graham Land