Native wildlife is threatened by invading species. It's estimated that more than 40% of species threatened with extinction are endangered by invasive species. Invasive species also pose risks to humans. They also are an economic risk factor. Entire industries, like fishing, depend on healthy aquatic ecosystems. Invasive species put the health of native wildlife and fauna at risk. Invasive species can also make a waterway unsuitable for recreational activities like swimming and boating.
What Is an Invasive Species?
Invasive species are ones that are simply not native to the location in which they are found. It doesn't have to be a mammal. Often, invasive species are types of algae, bacteria, fungi, plant life, fish, seeds, or amphibians. Because they aren't a natural part of their new environment they can cause great harm to it, sometimes because the home environment is full of natural predators that the new environment lacks. In the new environment, something that causes no issues in its natural environment can reproduce in great numbers. Sometimes the invasive species are from another country, but they can also be domestic. For instance, lake trout are an important part of the ecosystem of the Great Lakes. They were introduced in Wyoming's Yellowstone Lake where they are an invasive species because they compete with resources with the cutthroat trout, which is native to the region.
Invasive species are responsible for many different types of harm. The biggest reason is the new environment might not have any natural controls or predators that keep the population of the species under control. Native species might not be able to compete with the new species for valuable resources or might not have the capability to defend themselves against the new species. The native species often experience a decrease in fertility rates because the invader has decreased their access to food or introduced a new disease into the ecosystem. Invasive species can also destroy a diverse ecosystem and replace it with a monoculture. For example, kudzu often kills off other plant life in the area so kudzu is the only plant left. This change to the ecosystem can leave an area more vulnerable to natural disasters like flooding or wildfires.
There are many different types of invasive species. The Asian plant Cogongrass was simply seeds mixed in packing material when it arrived on U.S. shores. It's currently rapidly spreading through the United States. Native wildlife can't eat it, and it increases the risk of wildfire because it ignites faster and burns hotter than grasses native to the area.
Mammals can be invasive species. Feral pigs will eat anything, including native lizards and birds. They will consume food sources needed for native species. They also spread diseases to people, livestock, and even farm crops.
Back in 1989, the San Francisco Bay was invaded by European green crabs that devour native shellfish and has threatened the entire fishing industry in the region. The United States has about half the number of Elm trees it did before 1930. Why? Ophiostoma ulmi, a fungus, is spread by invasive elm bark beetles.
Invasive species are often hitchhikers. The European green crabs, for example, probably came along on the bottom of a cargo boat. Cogongrass seeds were mixed into packing materials. Campers bringing firewood from home sometimes, accidentally bring invasive species along on their trips. Boots, boats, tires, and cars can also introduce new species into an established ecosystem. Sometimes people purposefully introduce invasive species. For example, they plant an exotic plant in their garden and introduce something that destabilizes the native ecosystem. Or they tire of taking care of the fish in their aquarium and dump the creatures into a local waterway.
Clean, Drain and Dry Your Boat to Prevent the Spread of Invasive Species
Boaters play an important part in maintaining their local waterways. It is vital boaters drain all water from their gear and boat before entering or exiting a body of water. Most states have strict penalties for people who don't do this. The basic steps are to clean the boat, gear, and trailer of all mud, stuck-on objects (like shells), and plant matter. Drain all water from the boat. This includes bait buckets, the motor, live wells, and bilge. Then dry all the parts of the boat and the trailer for at least a week. If that's not possible, the boat and trailer should be thoroughly washed with hot, high-pressure water and lots of soap.
