Home What's New! Advocacy Nature Connection and Sanctuaries Membership Donations Birds & Birding Jobs Camp Audubon Shop
Living With Wildlife

Common Questions Answered:
   Birds: Attracting
   Birds: Identifying
   Birds: Behavior
   Birds: General Info
   Birds: Nests and Young
   Birds: Species
   Insects
   Mammals
   Miscellaneous
   Reptiles and Amphibians

Didn't Find Your Answer?
   Ask the Wildlife Expert!

Nature Connection
Conservation Science


Insects
print     e-mail    go back    

Winter Moths


Learn more!
Participate in a
related program.

No, those aren't snowflakes you're seeing out there—they're winter moths! The winter moth, Operophtera brumata, an invasive insect from Europe, introduced into the United States via Canada, has invaded eastern Massachusetts in huge numbers again this fall.

The adult winter moths emerge from the ground in November or December, but only the male is able to fly. The female climbs to the base of a tree or building and attracts the male through the pheromone (sex scent) that she exudes. After mating the female lays a cluster of approximately 150 eggs under tree bark or in tree crevices, and her life is now over. In March or April the eggs hatch into a smooth green inchworm with a narrow white-stripe running lengthwise on each side of the body. The caterpillar spins a strand of silk, which, with the help of air currants, takes it into tree canopies in a dispersal method know as "ballooning".

Once there, the damage to the tree begins as the caterpillars work their way into the tree buds and leaves to feed. In Massachusetts the tree species frequently affected are maple, oak, ash, as well as fruits producers such as apple, crabapple, and blueberry. Winter moth caterpillars can also drop from trees to nearby ornamental shrubs such as roses. When feeding ends in mid-June the caterpillars migrate into the soil to pupate and emerge as moths usually in late November or, as is the case this year, early November.

In 2005 and 2006, in a cooperative effort by the Department of Entomology at the University of Massachusetts and the Forest Health Program at the Massachusetts Department of Conservation and Recreation, hundreds of parasitic flies known as Cyzenis albicans were released at Wompatuck State Park in Hingham and on town-owned property in Wenham, MA. Cyzenis albicans has been effective in combating winter moth populations in Nova Scotia, as well as other parts of Canada.

The fly lays it's eggs on the leaves eaten by winter moth caterpillars during the spring. When the eggs are consumed, along with leaves, the eggs hatch inside the caterpillar and the larvae consume the caterpillar from within, eventually causing the moth to die. The fly pupates inside the carcass of the caterpillar and, the following spring, emerges as an adult fly to mate and begin the cycle again.

It is estimated that winter moths defoliated nearly 34,000 acres in eastern Massachusetts in 2005. And, although it will take several years to evaluate the effectiveness of the parasitic flies, it is hoped that they will have a lasting, negative impact on winter moth populations in the Commonwealth.

For more information:
http://www.umass.edu/umext/ipm/featured_pest/archive/winter_moth.pdf*
http://www.umassgreeninfo.org/fact_sheets/defoliators/wm_id_man.html
Mass Audubon's Wildlife Information Line: 781-259-2150


*Requires Adobe Acrobat Reader; click here for more information.


Participate in a Related Program
Turtle Trekkers, Stony Brook - 11/21/09
Naturalist Walk, Drumlin Farm - 11/21/09
Fireside Fables, Drumlin Farm - 12/1/09
Winter Rambles, Drumlin Farm - 12/3/09
Trailside Eco Explorers 1-Winter Session, Blue Hills Trailside Museum - 12/3/09
Early Winter Birds of Ipswich River, Ipswich River - 12/6/09
Fireside Fables, Drumlin Farm - 12/10/09
Oldsquaw Overnight on Nantucket, Wellfleet Bay - 12/10/09
Shrubs in Winter, Drumlin Farm - 12/12/09
Stars and Meteors at the Holidays, Broadmoor - 12/12/09
Holiday Hayride, Visual Arts Center - 12/13/09
Winter Walk, Felix Neck - 12/13/09
Seabirds & Seafood, Wellfleet Bay - 12/17/09
Winter Solstice 1, Drumlin Farm - 12/18/09
Winter Solstice 2, Drumlin Farm - 12/18/09
Turtle Trekkers, Stony Brook - 12/19/09
Naturalist Walk, Drumlin Farm - 12/19/09
Winter Solstice Celebration, Habitat - 12/19/09
Winter Solstice Lantern Walk, Ipswich River - 12/19/09
Winter Solstice Stories, Moose Hill - 12/20/09
Winter Solstice Celebration, Stony Brook - 12/20/09
Solstice Celebration, Arcadia - 12/21/09
Welcome Winter 1, Moose Hill - 12/23/09
Welcome Winter 2, Moose Hill - 12/23/09
Holiday Purge Hike, Wellfleet Bay - 12/26/09
All About Beads-winter break, Visual Arts Center - 12/28/09
December Vacation Adventures, Wellfleet Bay - 12/29/09
Wonderful Wood-winter break, Visual Arts Center - 12/29/09
December Vacation Adventures, Wellfleet Bay - 12/30/09
Wildlife Mural-winter break, Visual Arts Center - 12/30/09
December Vacation Adventures, Wellfleet Bay - 12/31/09
End of the Year Hike, Wellfleet Bay - 12/31/09
First Day Hikes, Blue Hills Trailside Museum - 1/1/10
Knee High Naturalists Winter 3, Moose Hill - 1/4/10
Knee High Naturalists Winter 4, Moose Hill - 1/5/10
Icy Investigations 1, Moose Hill - 1/6/10
Icy Investigations 2, Moose Hill - 1/6/10
Senior Stroll, Felix Neck - 1/6/10
Winter Rambles, Drumlin Farm - 1/7/10
Winter Botany and Tree ID, Drumlin Farm - 1/9/10
Winter Rambles, Drumlin Farm - 1/12/10
Fireside Fables, Drumlin Farm - 1/13/10
Birding the Winter Beach, Wellfleet Bay - 1/16/10
Turtle Trekkers, Stony Brook - 1/16/10
In Search of Winter Raptors, Drumlin Farm - 1/16/10
Winter Birds 2, Moose Hill - 1/20/10
Winter Birds 1, Moose Hill - 1/20/10
Fresh Air Lunchtime!, Habitat - 1/20/10
Fireside Fables, Drumlin Farm - 1/21/10
Naturalist Walk, Drumlin Farm - 1/23/10
Rhode Island Birding Weekend, Joppa Flats - 1/23/10
Fresh Air Lunchtime!, Habitat - 1/27/10
Superbowl of Birding VII, Joppa Flats - 1/30/10
Winter Raptors at Daniel Webster, Wellfleet Bay - 1/30/10
Fresh Air Lunchtime!, Habitat - 2/3/10
Winter Harvest Dinner, Drumlin Farm - 2/5/10
Winter Raptors, Blue Hills Trailside Museum - 2/6/10
Fresh Air Lunchtime!, Habitat - 2/10/10
Birding the Winter Beach, Wellfleet Bay - 2/13/10
Winter Raptors, Blue Hills Trailside Museum - 2/13/10
February Vacation-Who Survivies the Winter?, North River - South Shore - 2/16/10
February Vacation-Seals and Seashells, North River - South Shore - 2/17/10
February Vacaton-A Celebration of Winter, North River - South Shore - 2/19/10
February Vacation-Avian Architects, North River - South Shore - 2/19/10
The Birds of Duxbury Beach, Wellfleet Bay - 2/20/10

Back to top


Home | Contact Us | About | What's New! | Advocacy | Nature Connection | Membership | Donations
Birds & Birding | Jobs | Camps | Audubon Shop | Search | Program Catalog | Privacy Policy

©2003-2009 Mass Audubon. All rights reserved.