For several years I’ve been observing, documenting and appreciating nature and the environment in Michigan. During those years, I’ve discovered some of the subjects I’ve photographed and written about are in fact invasive species.
Photos Copyright Jeffrey Foltice
Some non-native species in Michigan can become established. At times they pose health risks to people and can cause economic harm or damage to eco-systems. One such example I’ve found in wetland areas of Michigan is an invasive grass called Phragmites australis.
This aggressive wetland grass outcompetes native grasses and effectively displaces local animals. A few of the other negative impacts from this grass include increased dangers of fire, elimination of natural feeding grounds and refuge for animals as well as an impact on open views that make recreational activities more difficult. ( They can grow to a height of over 19 feet in dense configurations ).
Another subject I have photographed that I later found to be an invasive species are Mute Swans. Originally brought to the Americas by Europeans in the mid 1800’s because of their beauty, these birds have quickly taken over wetland areas from native swan species as well as other waterfowl while increasing their numbers from 10 to 20 percent each year.
One example of their affecting another species directly can be shown with how they prevent native Michigan Trumpeter Swans from breeding. Both prefer the same habitats, but the Mute Swans nest three weeks earlier than the Trumpeters. Once nesting begins, the Trumpeters are prevented from entering the area by the Mute Swans. They also tend to be aggressive toward humans at times when they are guarding their territory and have been said to be the most aggressive waterfowl species in the world.
Another picturesque invasive species, purple loosestrife ( Lythrum salicaria ), has taken over many wetland areas throughout the United States and Canada. Since the early 1800’s when brought from Europe, this plant has suppressed native vegetation and changed the ecology of wetland areas as a result. There are programs introducing biological control through the use of the plant’s natural enemies, such as leaf-eating beetles, which help to keep the growth somewhat in check.
As I continue to explore and enjoy nature in Michigan, I’ll endeavor to be more aware of what I may find. Although these are often beautiful photographic subjects, they can also be destructive and disruptive to native species.