National Invasive Species Awareness Week

Here in Colorado we have a number of invasive species that are causing problems because they can harm the environment and put native species at risk. Colorado Parks & Wildlife defines invasive species as “plants, animals, insects or diseases that are not native to Colorado.” CP&W explains that “because they are not native to Colorado habitats, they have no natural competitors or predators. Without these checks and balances, the invaders are able to reproduce rapidly and out-compete native species.”

How do these invasive species get here? They mostly arrive by accident, “hitching a ride” on products being shipped into the state, or from human travel. But some introductions can be avoided. For example, bullfrogs, who occur naturally in the eastern and midwestern US but not in Colorado, were introduced here in part as discarded lab animals. The bullfrogs are a problem, according to CP&W’s species profile, because “bullfrogs eat anything that moves and will fit into their mouths including fishes, frogs, birds, bats, snakes, tarantulas, small mammals, and a variety of invertebrates. They out-compete and eat native amphibian species and are a factor in native species population declines.” Another example is the piranha, introduced into Colorado waters as unwanted pets. For more on these and other Colorado wildlife, both native and non-native, check out CP&W’s species profiles page. For more on the problem of releasing non-native species into the wild, see CP&W’s Don’t Turn it Loose webpage. Invasive plants such as purple loosestrife have also been introduced intentionally (though likely unknowingly), introduced for use in gardens but quickly reproducing and spreading. Finally, you can avoid transporting invasive insects by not moving firewood out of affected areas.

As our world becomes more connected invasive species are becoming a greater problem, not just in Colorado but across the nation. Therefore February 26-March 3 has been set aside as National Invasive Species Awareness Week.

Here are some of the most problematic invasive species in Colorado, and state publications and websites that can help you learn more:
Emerald ash borer:

The emerald ash borer

Field bindweed:

Field bindweed flower

Gypsy moth:

Gypsy month

Japanese beetle:

Japanese beetle

Meadow knapweed:

Meadow knapweed

Mountain pine beetle:

Mountain pine beetle

Purple loosestrife:

Purple loosestrife

Rusty crayfish:

Rusty crayfish



Yellow starthistle:

Yellow starthistle

Zebra and quagga mussels:  

Quagga mussel

For general information on invasive species in Colorado, see the following state publications:

Photo credits:
Colorado Department of Agriculture: Emerald ash borer, field bindweed, meadow knapweed, purple loosestrife, yellow starthistle
Colorado Parks & Wildlife: Rusty crayfish, waterflea, quagga mussel
Colorado State Forest Service: Gypsy moth
Wikipedia: Japanese beetle, mountain pine beetle