The Wild Side: The dangers of invasive wildlife species
Right now hunters are really hitting the woods, pursuing small game as well as deer and turkey. There are many trail cameras in the woods, and more are being put out every weekend. If you get any photos or observations of an unusual animal, you can report it to the DNR on their website. If you get any photos or observe any feral (wild) pigs, we really need your help to control them. Feral pigs were sighted on state land near Rhinelander in 2007, and on a Vilas County trail camera in 2011. These animals are highly destructive. You can legally shoot wild pigs with a small game license. We ask that you contact the local wildlife biologist (me) or conservation warden Jim Jung upon harvest of a feral pig so we can collect a blood sample, routine protocol for disease surveillance. You get to keep the rest of the pig.
Feral pigs are one example of invasive wildlife species that can cause a large amount of damage. Since this country was settled, wildlife has been imported by citizens, government officials, crop producers, the pet trade, shipping containers and other means. Some of these animals, like European starlings, may not have a great impact on our daily lives. Others, like the cane toad or python in Florida, are killing wildlife and pets, and even injuring people. As a wildlife biologist, I closely watch the concerns our country has about invasive wildlife species. According to the National Wildlife Federation, about 42 percent of our country’s threatened and endangered species are at risk because of an invasive species. I will delve a little more into this crisis, and its apparent link to climate change, in a future doomsday series I am planning. For now, let’s just say that invasive wildlife species are successful because they are usually very good at surviving and reproducing. They are willing to eat almost anything, live almost anywhere and they have no natural predators. They have an unfair advantage and a good head start, and once numbers get away from wildlife managers, they are almost impossible to control.
Before we drown in a pool of our own tears, though, we should consider the possibility that we have inflicted similar monstrous critters on other continents. For example, there is a furry marauder that is overtaking the British Isles, and there seems to be no stopping it-our own Eastern or gray squirrel. The raccoon is also marching across the globe, terrorizing Japan and Germany, so much so that there is an industry devoted to trying to exclude them from homes, and capture and destroy them whenever possible. I did a bit of research, and found an information clearinghouse for European invasive species. DAISIE, which stands for Delivering Alien Invasive Species Inventories for Europe, recently came online, and still has a lot of incomplete information. It is an excellent website, though, and if you know your binomial nomenclature, you will have no trouble using it.
I checked out the website’s list of the top 100 worst invaders and recognized some creatures we appreciate here in the United States. The Canada goose, American mink and Ruddy duck joined raccoons and squirrels. Further down the list were the wood duck, blue-winged teal and American robin. These are serious threats to wildlife across Europe and are the subjects of extensive control programs. The Ruddy duck, for example, has been the target of extensive control efforts since the early 1990s and their numbers continue to spread. They apparently displace a native duck that can interbreed with Ruddies, which puts it at risk for extinction.
Dealing with invasive wildlife species is one of many duties that wildlife management staff conducts that normally does not draw much attention. We use the best available science to monitor and control them. For species like feral pigs, help from hunters is crucial-keep your eyes open.
Jeremy Holtz is a wildlife biologist with the Wisconsin DNR in Rhinelander, and writes a weekly column in the Star Journal. To contact him, call (715) 365-8999.