Non-native invasive species by Sean Obrien
One of the biggest threats to our local environments is the threat and introduction of non-native invasive species. In fact, it is the second biggest threat to native species behind only habitat destruction. These unwanted guests can decimate populations of essential species of plant and animal life in specific areas, and cause untold damage to the future of our biodiversity. Although there are numerous laws and regulations regarding the introduction of non-native species to an environment, it still happens frequently. And in the case of some areas, the damage is far too great to be undone.
One of the worst examples of non-native invasive species and the damage they can cause is the lionfish. Although the true cause of their introduction into the non-native waters of the East Coast and the Caribbean, we can basically determine that people have been dropping off unwanted lionfish from home aquariums into the Atlantic Ocean. The biggest issue with the lionfish is that they feed on some of the most important commercial species of fish and crustaceans, competing with native species for limited resources. They do not have many natural predators, due to poisonous spines that are found all along their back and hinder them as far as prey for other species. They are also not a commercially viable food product, therefore limiting the appeal to catch them.
The snakehead, which is an amphibious fish native to Africa and Asia was introduced in the United States, and although it is unclear whether it was intentional or accidental, it is here to stay. In the Potomac River in Maryland, the Northern Snakehead has been established, and it boasts a population at least 21,000 strong. The snakehead can become an invasive species because of its top predator status in non-native areas, and the absence of any predators. Another issue with the introduction of this fish is that the females can lay 15,000 eggs at a time, and can mate up to 5 times per year. So theoretically, a single female can lay 150,000 eggs in a two year period. This could cause a drastic boom in a population and essentially create a situation where the native species could be decimated. Snakeheads are raised as a food source in many other countries, and that could perhaps help to control these populations in the US. But the reality is, they have been found in states as varied as California, Florida, Hawaii, Maine, Maryland, Massachusetts, and Rhode Island.
There are many different species of carp, and many have been introduced to areas of the United States where they have developed a non-native population, and in some cases have caused devastation. The asian or silver carp is one of the most well-known invasive species in the USA, and it is because of videos. TO start with, the silver carp was brought to the US because, as a filter feeder, they are great at combating the algae growth in aquaculture, but they soon escaped captivity and ingrained themselves in the hearts of many of the rivers criss crossing America, including the Mississippi, Illinois, Ohio and Missouri Rivers. The silver carp is also called the flying carp, and it became famous for videos posted on youtube of boaters on the Mississippi River being inundated with carp jumping as the boat engine startled them.