SHUT DOWN
Federal and state agencies are working with pet and aquarium stores in the United States to remove mossballs infected with zebra mussels. Here’s why.
Week
The introduction of an invasive species is usually unintentional: it wanders the steps of a hiking shoe, gets stuck in the bottom of a boat, or a pet escapes into the wild.
However, it doesn’t take long for these species to cause serious damage. That’s because they’re not native, which means they don’t have natural predators and often have other traits that give them an advantage over native species.
Invasive species come in all shapes and sizes. They can be plants, reptiles, beetles, and mammals. They can be as small as a bug or as big as a wild boar.
Indiana has more than 20 invasive animal and insect species that pose a threat across the state. And similar to invasive plants – there are more than 50 in Indiana – some of these animal species are the ones humans would least expect.
Take the mute swan, for example.
You’re a beautiful bird, said Emily Wood, executive director of the Indiana Wildlife Federation. But that can make it difficult to convince people that these animals are a problem or shouldn’t be here, she added.
Once established, the invasions can disrupt, if not completely decimate, the natural ecosystem. In addition, they are particularly difficult and expensive to eradicate.
Here’s everything you need to know about five of the most harmful invasive species of animals and insects in Indiana.
Asian carp
Asian carp is the No. 1 invasive animal for wood. In fact, there are four different types of carp in Eurasia: thick-headed, silver, black and grass carp. You know them, they are the fish that fly out of the water when you zoom past in a motorized boat.
Silver carp (Photo: Marlin Levison AP)
These fish have disrupted fisheries in the South and Midwest and are knocking on the door of the Great Lakes. Wildlife and conservation experts have invested millions to keep these fish out of the lake system. They are concerned about what is at stake if they break through.
Carp are fast growing and productive feedstuffs that hoard food resources and outperform native sport fish. They were found in the Wabash River in Indiana and drove up the White River to Indianapolis.
Gypsy moth
The gypsy moth is one of the most devastating invasive forest pests in North America, according to the Indianapolis Department of Natural Resources.
Originally from Eurasia, the moth appeared more than a century ago when it was accidentally introduced near Boston. Since then, it has spread to the northeast and the Great Lakes states of the upper Midwest.
The preferred food of the gypsy moth is oak leaves, but they can eat the leaves of more than 500 different trees and plants. When their population reaches a sufficiently high level, trees can be completely defoliated. Not only does this harm other species that rely on these plants, but multiple consecutive years of defoliation can often kill the tree.
It is known that large numbers of gypsy moth larvae defoliate huge parts of the eastern forest. (Photo: DEAN FOSDICK AP)
Zebra mussels
These clam-nail-sized clams are considered one of the most destructive invasive species in North America, according to the U.S. Fish and Wildlife Service. They can be recognized by their light and dark zigzag stripes that resemble a zebra.
Native to Eurasia, these clams were first introduced in the 1990s when ballast water was being dumped in the Great Lakes. Since then, they have devastated the lakes’ aquatic food chain and spread to many inland lakes in the region.
Zebra mussels (Photo: US Fish and Wildlife Service)
These clams reproduce quickly and cling in clumps, eating plankton and other algae that are the food source for native fish and insects. They’ve also increased the effects of harmful algal blooms as the clams spit out the poisonous blue-green algae and allow them to spread. Zebra mussels have also cost cities and industries millions of dollars by clogging pipes.
Wild pigs
Also known as wild boar or wild boar, it is an invasive species that has either been released illegally or is a previously domesticated pig that was allowed to go wild. There is currently no established population of wild boar in Indiana, but the Indiana DNR has identified them as a serious threat to watch out for.
The pigs are opportunistic feed, and their rooting can damage crops, parks, wildlife nesting areas, and even golf courses or some rural cemeteries. They also compete for food with native wildlife, and species such as deer and nesting turkeys avoid areas where pigs are active.
These wild boars can also transmit diseases that can spread to domestic pigs and other animals. Some diseases can infect humans as well, and the pig’s waste can contaminate human food sources and water supplies, according to the DNR.
Wild pig (Photo: US Fish and Wildlife Service)
Mute swans
There are three types of swans in Indiana: two are native and one, the mute swan, is not. You will recognize the mute swan by its orange beak, and it is the only swan likely to be in areas that are frequented by humans. This is what most people think of when they think of a swan.
Mute swans were introduced to Indiana from Europe as an ornamental species. However, native plants and animals have not adapted to these invasive birds. These swans require eight pounds of aquatic plants daily for food and eat what is normally available to native waterfowl. They also destroy habitat while feeding, decimate cover for native species, and allow aquatic weeds and invasive plants to spread.
These invasive swans are also very aggressive and are known to attack native species. And people. Mute swans are still protected in Indiana, so special permission is required to remove them or perform nest checks.
Buy photo
You can tell the difference between a mute swan and native swans by its beak. The beaks of the native trumpeter and tundra swans are black. (Photo: ROB GOEBEL)
Call IndyStar reporter Sarah Bowman at 317-444-6129 or email sarah.bowman@indystar.com. Follow her on Twitter and Facebook: @IndyStarSarah. Connect with IndyStar’s environmental reporters: Join The Scrub on Facebook.
IndyStar’s environmental reporting project is made possible through the generous support of the non-profit Nina Mason Pulliam Charitable Trust.
Read or share this story: https://www.indystar.com/story/news/environment/2021/03/15/these-5-invasive-species-animals-and-insects-decimating-indianas-environment/4668603001 /
