BEND, OR -- It's been a banner year for insect outbreaks in Central Oregon, and the latest is arguably the prettiest. The tortoiseshell butterfly experiences a huge upswing in population about every decade, and it's back in the area, again.
Rob Flowers, with the Forest Service, says the butterflies aren't dangerous, but admits they can create a mess. "This is one of the only ones that goes into a real high population strength certain years, and it's usually for only a year or two. But, their habit is to fly over large areas in large numbers so, as they move across roads, the gross factor comes in terms of hitting a lot of them with your car. So, if you're traveling across the passes right now, or if you're up in the higher elevations, you'll see a lot of these butterflies flying around."
Because they fly in large groups, Flowers says it can make them difficult to photograph. Flowers tells KBND News, "The larvae are black and they have yellow spines on them. They'll complete their lifecycle and turn into an adult and that's when you get the sort of mass, the flight of the butterflies. The adults tend to be mostly yellow orange with some black spots and then a black border on the wings." He adds, There's just hundreds of butterflies just fluttering by, so it's an interesting thing to observe. It's a fairly common occurrence; we just haven't seen them for awhile. If you're new to the area, it might be something that's kind of novel. We do have some records- we've seen fairly regular outbreaks that date back to the early 1900s, so this is just another in the long series of nature doing something spectacular." Flowers expects the tortoiseshell butterfly will be in the area for four to six weeks.