Invasive Species Under Your Nose - European Earwig

Do you stop to smell the roses? If you do, you’ve no doubt met a common invasive insect, the European earwig. They love to hide in roses and other nooks and crannies that offer shelter and high humidity.  At my house they like my hose reel.  I even saw some on the roof recently while I was cleaning off moss.

There are no native earwigs in Oregon; if you see one, it’s an invader.  By far the most common is the European earwig, Forficula auricularia L.  Earwigs are omnivores, occasionally becoming minor pests.  Mostly they are just a nuisance or to the entomologically inclined, a curiosity.

I’ve had a soft spot for earwigs since encountering very large maritime earwigs while processing seaweed in a previous job on the East Coast.  Like all earwigs, they have prominent cerci (forceps) at their tail end. Interestingly in this species, the cerci are curved and asymmetrical in the male and straight in the female.

Cerci, used for mating and defense, are not the only odd thing about earwigs.  Here is some more earwig trivia: Unlike other insects, the mothers stick around and protect their young after they hatch.  Though they appear wingless, many species can fly; their wings are folded up under small wing covers on their thorax.  Earwigs are an ancient group; they were crawling around under the noses of dinosaurs.

Oregon has a very interesting history with earwigs.  In the 1920s and 1930s, Oregon State Agricultural Experiment Station, State Board of Horticulture, Bureau of Entomology, City of Portland, and Multnomah County cooperated on earwig surveys and releases of biological control agents.  For a while, Portland even had a City Earwig Commissioner!

Here is an excerpt from a 1930 report: “A brief survey was made to determine if European earwigs were present in all parts of Portland, except in the main business district.  This survey was conducted by placing tar paper bands on trees and the relative number of earwigs found under each tar paper band was noted.  It was found that earwigs were present in every section of the city in large numbers.”1

It would be interesting to repeat the survey now.  Perhaps the parasites introduced way back then are the reason European earwigs are not a serious problem now.  To my knowledge, no one has followed up in the 90 years since.  Anyone know a student in search of an interesting science project?

Another interesting project would be to survey for the maritime earwig.  They have been introduced and become established in both California and British Columbia.  If they aren’t in Oregon yet, they probably will be soon.  Keep your eyes open next time you’re at the coast, you could be the first to report this exotic species!

Earwigs are an example of an invasive species right under your nose, but don’t worry about them crawling in your ears – that’s an old wives tale!

Dan Hilburn


¹D.C. Mote.  1931. The Introduction of the Tachinid Parasites of the European Earwig in Oregon.  J. Econ. Ent. 24: 948-956.

Summer's Bounty and the Ongoing Threat of Invasive Species

Some people measure the passage of time with changes in weather and leaves falling off trees. I measure it in canning jars and freezer space.

At the start of summer, my stack of empty canning jars in the garage reaches the ceiling and my freezers are mostly empty. At the start of fall, there are no canning jars in the garage, and my pantry is chock full of all kinds of delectable foods. This years' canning tally resulted in 10 quarts of applesauce, 16 pints of salsa, 50 pints of tuna, 16 pints of jalapeno peppers, 16 quarts of green beans, 40 pints of pickles, 11 quarts of kale, and 12 pints of jam -- all except the tuna was grown in our garden. And our freezers are full of corn, smoked poblano peppers, jam, green beans, strawberries, blueberries, kotataberries, loganberries, eggplant, and broccoli. Our dry storage is piled high with garlic, shallots, and potatoes. It will be a good winter.

But I'm worried about the future. In just the past couple of years, light brown apple moth has been knocking on Oregon's door from the south. Last year, Drosophila suzukii, a type of fruit fly, devastated the peach crop at an orchard a few miles from my house. And there's a host of other invasive diseases and insects that threaten Oregon's produce, ranging from blueberry hill carlavirus and potato wart to bacterial blight of grapes -- not exactly coffee shop subjects, but invasive diseases and pests that have the potential to change what I value in life.


A statewide assessment conducted by the Oregon Invasive Species Council showed Oregon spent about $28 million on invasive species management and control in 2008 -- and that was only for entities that participated in the assessment. It's very likely when you add up the total that everyone in Oregon spends on invasives, we're well into the hundreds of millions. Yet the list of invasives knocking on our door that have the potential to change our way of life and further impact Oregon's economy grows larger.


We must remain vigilant -- the future of Oregon is at stake.


Lisa A. DeBruyckere, Oregon Invasive Species Council Coordinator

When Aquarium Fish Go Awry

With their feathered fins and outrageous colors and patterns, lionfish, native to the Indian Pacific ocean region, are a favorite of many aquarium owners. They are so popular that seemingly innocent aquarists have released some into waters off the coast of Florida and in the Caribbean and Bahamas. After all, if they're amazing to look at in an aquarium, imagine what they would look like to a snorkeler or diver in coral blue waters.

Unfortunately, these fish come with some hefty baggage. They have no predators in their food chain, except for their two-legged  admirers. Lionfish are voracious predators and love the lip-smacking delicacies of young grouper and snapper and the invertebrates that make up the base of the food chain in coral reef ecosystems. And lionfish are highly venomous, with sharp dorsal spines to protect themselves.

How do we rid ocean environments of invasive fish species? It's not an easy task, but Florida wants this species removed from the Florida Keys National Marine Sanctuary. So they held a fish derby that attracted 27 teams comprised of a total of 100 trained divers. Their mission? Dive in the sanctuary and carefully capture lionfish for the chance to win montetary prizes.

The first of three planned Keys-based lionfish derbies attracted 27 teams that competed for cash and prizes to collect the most, largest and smallest lionfish. The day ended with a grand tally of 534 lionfish that are no longer bullying their way around the sanctuary. The derby was so successful that two more are planned.

And how did they celebrate their success? Lionfish are considered a delicacy because of their flesh, a dense white meat. Divers gathered at a local restaurant to enjoy their bounty and plan for the next event.

Can these derbies result in total eradication of lionfish in ocean ecosystems? Not likely. A total of 27% of all mature lionfish would have to be removed annually just to make a dent in reducing population numbers. But the derbies go a long way toward highlighting the havoc that aquarium species wreak when released into the wild.

All of us can learn from what is happening with aquarium species in other parts of our country and the world. Use aquarium species responsibly and protect Oregon's native fish and wildlife.

Lisa DeBruyckere, Oregon Invasive Species Council Coordinator

Changing the Perpectives of Viewscapes

If Lewis and Clark could see parts of the West today, they might not recognize it. What was normal to them as they made their way through the great Pacific Northwest 205 years ago was largely pristine wilderness. So pristine, in fact, that they  cataloged many native and as yet undescribed specimens for Thomas Jefferson and others who had only heard about what lay west of Missouri and beyond.

Oregon still has a large percentage of its native ecosystems. We are, in fact, one of the few states in the nation that hasn't experienced the wrath of large populations of feral swine in our riparian corridors, or emerald ash borer and gypsy moth defoliating swaths of forest and urban landscapes.

How can we protect what we still have while doing battle with new invasives? The greatest threat to Oregon's ecosystems is not transportation, ignorance, or our global economy -- it's public perception of viewscapes.

There are many people that enjoy the flowering yellow brilliance of scotch broom along Oregon's interstates. Others are almost protective of their patches of Himalayan blackberry. And some see nothing wrong with bullfrogs in Oregon's wetlands. 

But all of these are invasive. None of these examples are the real Oregon. And all threaten the future of Oregon's ecosystems and the native fish and wildlife that can thrive there.

We're about rhododendrons and red flowering currants. We're about huckleberries and elderberries. And we're about Pacific treefrogs.

Let's not settle for anything less.

Lisa DeBruyckere, Oregon Invasive Species Council