Non-native Species

I do most of my running on the Jordan River Parkway that parallels the Jordan River in Utah. I've seen red tags on many of the trees and bushes, and I wasn't sure if those plants were marked to be protected or to be destroyed. One day I saw a man putting tags on bushes, and I asked him about the purposes of the tags. He said the tags were markers for plants that shouldn't be destroyed. He said that the river-area is covered with non-native species, and those plants will be destroyed. The non-native species are beautiful and contribute to the "green" feeling of the Parkway, but it is costing the county mega dollars to remove them and convert the area back to its native appearance.

A parallel to non-native species are new species that may be native to the area, but because they are new, they have a similar effect on the environment and people as non-native species.

Here are links to science articles about non-native species.

"The impacts of exotic plant invasions often take much longer to become evident than previously thought," says Benjamin Gilbert of U of T's Department of Ecology & Evolutionary Biology (EEB) and lead author of the study. "This delay can create an 'extinction debt' in native plant species, meaning that these species are slowly going extinct but the actual extinction event occurs hundreds of years after the initial invasion."

Foreign invaders such as pythons and lionfish are not the only threats to Florida's natural habitat. The native Carolina Willow is also starting to strangle portions of the St. Johns River.

The future landscape of the American Midwest could look a lot like the past -- covered in native grasslands rather than agricultural crops. This is not a return to the past, however, but a future that could depend on grasslands for biofuels, grazing systems, carbon sequestration, and other ecosystem services. A major threat to this ecosystem is an old one -- weeds and their influence on the soil.

"It used to be rural areas where we would have this challenge of coexistence versus conflict with carnivores. In the future, and I would say currently, it's cities where we're going to have this intersection between people and carnivores," he said. "We used to think only little carnivores could live in cities, and even then we thought they couldn't really achieve large numbers. But we're finding that these animals are much more flexible than we gave them credit for and they're adjusting to our cities.

This adaptive nature demonstrated by introduced species could serve them well as the climate continues to warm. At the same time, the non-natives' potential ability to become even more invasive could threaten the survival of native species already under pressure from land-use changes, researchers say.

The length of time required to manage invading species is another factor. While an herbicide may make inroads into reducing an exotic species of plant in 2 to 3 years, this does not mean that the native species will once again dominate. The best results were seen when reseeding of native grasses followed herbicide application.

The Everglades National Park in Florida is home to hundreds of species of native wildlife. It has also become the well-established home of the non-native Burmese python -- known to be a predator of native species. Now scientists, for the first time, have conducted a detailed analysis of the avian component of the python's diet and the negative impact the snakes may have on Florida's native birds, including some endangered species.

In the six decades from 1950 over 600 non-native species have arrived in Britain. Invasive non-native species are considered to be one of the five major threats to biodiversity, and have been estimated to cost the UK economy £1.7 billion per annum.

University of Notre Dame entomologists are part of a team of researchers that recently discovered a potentially dangerous new malaria-transmitting mosquito. The as yet unnamed, and previously unreported, mosquito breeds in the western areas of Kenya and has an unknown DNA match to any of the existing malaria-transmitting species.