An online resource based on the award-winning nature guide

Posts tagged “Emerald Ash Borer

Cold Snaps & Hardy Invertebrates

1-14-14 TICK IMG_0528As you may have heard, there could be a plus side to the sub-zero temperatures we’re experiencing this winter – the cold weather may well decrease the number of invasive pests we have. For example, the Hemlock Woolly Adelgid (the aphid-like introduced insect decimating the Eastern Hemlock population) succumbs at 4 or 5 degrees F. However, other insects aren’t phased by the cold until it dips way below zero. At -20 F., roughly half of the Emerald Ash Borer larvae (an invasive beetle that is highly destructive to ash trees) overwintering in trees will die. Once the temperature reaches -30 F., there’s a 90 percent mortality rate. Bed bugs face instant death at -22 degrees F., but it takes 24 hours to kill them at -11 degrees F. and 72 hours to kill them at 0 degrees F. Unfortunately, once an invasive insect establishes itself, even if its numbers go way down for whatever reason, it usually rebounds in several years’ time. Some invertebrates are not affected by the cold temperatures. The Black-legged (Deer) Ticks that reside on moose, deer, mice, birds and other hosts can withstand sub-zero temperatures as they have the warmth of their hosts’ bodies to keep them warm. In order for ticks to succumb to the cold, the frigid air has to last until May, when the fertilized female ticks fall off their hosts to lay their eggs.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Cerceris fumipennis: a biosurveillance tool for the emerald ash borer

8-19-13 Cerceris wasp with beetle prey2 099While we’re more familiar with social wasps, such as paper wasps, yellow jackets and hornets, there are also parasitic and solitary wasps. Solitary wasps live alone (as their name implies), all the females (not just the queen) are fertile and they are predatory. Among them is a wasp, Cerceris fumipennis, which preys exclusively on the family of beetles (Buprestidae) to which the Emerald Ash Borer (EAB), the invasive beetle that’s threatening the ash tree population, belongs. After catching and paralyzing its prey, the wasp carries it back to her larvae in the nest she’s dug underground. A biosurveillance program exists which involves monitoring the prey that this species of wasp collects and brings back to the nest, in order to detect the presence of the Emerald Ash Borer in any given area. (This is how the EAB was first detected in Connecticut.) Pictured is a Cerceris fumipennis wasp with a Buprestid beetle (not an EAB) prey. (To become involved in Vermont’s citizen science biosurveillance program next summer, contact entomologist Trish Hanson of the Vermont Dept. of Forests, Parks and Recreation at Hanson.Trish@state.vt.us .)

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.