Dragonflies are one of the insects tricked by false light (Photo courtesy of the EPA)
Bugs are getting confused by the
reflections from manmade structures.
Rebecca Williams reports on a new study:
Transcript
Bugs are getting confused by the
reflections from manmade structures.
Rebecca Williams reports on a new study:
If you’ve ever noticed swarms of insects hovering over your car, there’s a
good chance they’re mistaking it for water.
Smooth, dark surfaces like cars and asphalt reflect polarized light. That’s
what bugs see – and that tricks insects such as dragonflies.
Bruce Robertson is an author of the study in the journal Frontiers in Ecology
and the Environment.
“Asphalt actually reflects polarized light more strongly than water and so it
looks more like water than water! And so these organisms are thinking
they’re finding a place to breed and hunt and lay eggs and mate when in fact
they’re finding a place that’s very dangerous.”
Robertson says these bugs swarm over buildings and roads in huge numbers,
and can die of exhaustion.
But he says it might be possible to stop tricking the bugs. Things like
adding white curtains to dark windows or adding a little bit of gravel to
asphalt to make the surfaces reflect less polarized light.
Salamanders are a good indicator of wetland health. (Photo courtesy of the Washington Department of Fish and Wildlife)
Government workers are slogging around in man-made wetlands.
looking for salamanders. Back in the 1950’s, the United States government
selected a plot of land to be the home of its newest uranium processing plant.
Since the end of the Cold War, the now-closed nuclear processing plant has
been undergoing the long and arduous task of returning to its natural wetland
state. The Great Lakes Radio Consortium’s Tana Weingartner reports on the search for salamanders at the site, and why
their presence is so important:
Transcript
Government workers are slogging around in man-made wetlands looking for salamanders. Back in the 1950’s, the United States government selected a plot of land to be the home of its newest uranium processing plant. Since the end of the Cold War, the now-closed nuclear processing plant has been undergoing the long and arduous task of returning to its natural wetland state. The Great Lakes Radio Consortium’s Tana Weingartner reports on the search for salamanders at the site, and why their presence is so important:
It’s a cold, windy day in late March as specialists from the Ohio Environmental Protection Agency head out to check their traps at the Fernald Nuclear Plant. The 1050-acre facility sits in a rural area just 18 miles north of Cincinnati. Although the EPA is in charge of cleaning up the uranium contamination here, today they’re on a different mission. Today they’re hunting salamanders.
“Salamanders basically are a sign of an established wetland usually, and in this case would show that we put a wetland in a location where salamanders need additional breeding habitat.”
In other words, Schneider says the presence of salamanders indicates the first level of success for these manmade wetlands. The wetland project is one of several ways the EPA is ensuring Fernald is properly restored to its natural state.
“Well, we’re looking forward to the day when we get the site cleaned up, and it can be like a land lab, and people can bring kids out here and do environmental education on the importance of wetlands, and it’s going to make a great contrast with what used to be here and the environmental contamination with the environmental benefit the facility is providing down the road.”
Today, the site is 70 percent certified clean, and officials expect to finish the cleanup by June 2006. Creating healthy wetlands full of insects, amphibians and salamanders is one of the first steps to success.
“So the method here is to set ten traps equidistant, hopefully, around the perimeter of the wetland. And they’re passive traps, whereby animals that are moving over the course of the 24 hours or so that the traps have been in, will bump into the traps and it’s a funnel that directs them into the center part of the trap, and they’re held in there until we release them.”
(splashing sound)
Schneider and his team laugh and joke as they pull the traps up by brightly colored ribbons. Train horns and construction noises mix with bird calls – one a reminder of what has been, the other a sign of what’s to come.
“That’s probably a one-year-old bullfrog there and then these big guys are dragonfly larvae and these other guys are back swimmers. Mayfly larvae and dragonfly larvae are both good indicators of high water quality.”
The third pond, or vernal pool, turns up 46 tadpoles and a tiny peeper frog, but no salamanders.
(truck door slams)
So it’s back in the truck and on down the dirt road to where several more wetland pools sit just across from the on-site waste dump. That dump will be Fernald’s lasting reminder of its former use. These pools are younger and less established, but they do offer hope. Last year, adult salamanders were found in the one closest to a clump of trees.
Each spring, as the snow melts away and temperatures rise, salamanders venture out in the first 50-degree rain to begin their search for a mate. Schneider had hoped warm temperatures in late February and early March prompted “The Big Night,” as it’s known.
“So, no salamanders today?”
“No salamanders today. I think we learned a little bit about the difference between wetlands that are three years old. We saw a lot more diversity in the macroinvertebrates, the insect population, than we have down here.”
Perhaps the salamanders haven’t come yet, or maybe they have already come and gone, leaving behind the still un-hatched eggs. Either way, the team will check back again in April and a third time in late May or June.
“And we have high hopes, high hopes, high apple pie in the sky hopes. That’s the kind.”
Researchers in Wisconsin have identified a species of dragonfly never
seen in the state before. They’ll be watching it as a possible
indicator of global climate change. The Great Lakes Radio Consortium’s
Stephanie Hemphill reports:
Dragonflies are one of the insects tricked by false light (Photo courtesy of the EPA)