February 23-28, 2014 is National Invasive Species Awareness Week. This has got me thinking about what invasive species live in my area of San Diego. It was easy to come up with many of them. Some species are brought here with good intentions that go sometimes go wrong, some are brought here by accident and some are brought here with positive results. Here are a few that live in San Diego and possibly elsewhere, that aren’t really native to the area.
Feral pigeon: Most people don’t know that the common rock dove, also known as a rock pigeon, is not native to the western hemisphere. They were actually kept as domestic livestock or as a hobby dating back to the 1600s. Some were trained to carry messages during wartime or for other reasons. They are native to Europe and Asia.
European starling: These actually came to San Diego later than they did to other areas of the country. They were purposely introduced in the eastern United States in the late 1800s by Shakespeare enthusiasts who wanted this country to have all the birds mentioned in Shakespeare’s plays. This bird has done a lot of damage to native species mostly due to their aggressiveness and competing with nesting cavities.
English sparrow: Another purposely introduced bird that has been destructive to native species and to farming. This species was released in 1851 because some people missed the familiar birds of their homeland. Since then, they have spread throughout the North America. In many places in the world, they are considered a pest as they consume a lot of grain and can clean a barrel of livestock feed in a short amount of time.
American bullfrog: While this animal is native to many areas of North America, they were introduced here in San Diego by farmers for their legs which are a delicacy in some areas. However, these large frogs are destructive to native animals and often eat baby waterfowl, snakes, and small birds.
Red-eared slider turtle: This turtle was and still is a popular pet in the United States, but it is not native to San Diego. This is a common turtle seen in most freshwater areas around the county. They are a danger to small animals, but generally become more vegetarian as they get larger. They are also crowding out native turtles.
Most of these species are here to stay and are difficult to control. One thing that can help is not to release pets into the wild or allow them to escape. All of these animals were originally released pets or domestic animals.