When a deer collides with a vehicle that weighs a couple of tons, the fragile animal almost always gets the worst of it. When a deer meets a motorcycle on the roadway, both the rider and the deer may suffer the same fate.

Research by AAA released Monday found that seven of the eight people who died in crashes involving deer over a three-year period in Maryland and Virginia were motorcyclists. Nationwide, the auto club said, about 70 percent of deer-crash fatalities involve motorcycles.

The deer mortality rate becomes most evident this time of year, as the mating season has more deer on the move. Their carcasses by the roadside attest to the danger that the lure of romance poses for them and for drivers.

“Because they are riding on two wheels, motorcycle riders and their passengers are especially vulnerable when they smash into a deer,” said John B. Townsend II, an AAA spokesman. “Such motorcycle-deer strikes can be frightening and even fatal.”

Two of the three people killed in regional crashes involving deer this year were motorcyclists, Townsend said.

The proliferation of deer and other species in urbanized regions, where they have few, if any, predators, has become apparent by their appearance beside the highway. In some parts of the Washington region, red fox as roadkill was almost as common as the squirrel this summer. With the end of the season when deer are busy giving birth and raising doe, dead deer are showing up more frequently.

Data presented last year by the Insurance Information Institute, an industry group that has access to insurance claims information, indicated there are about 80,000 collisions with deer each year in the Washington region. The institute said Virginia ranked 12th and Maryland 13th when comparing the likelihood of a deer-vehicle crash with data from other states. It estimated cost of the collisions in 2009 at $4.6 billion.

In 2010, the latest year for which there are national statistics, 403 people were killed in accidents involving deer, one of the lowest totals in three decades.

The AAA compiled this list of Maryland and Virginia encounters with deer in which a motorcyclist was killed:

In August, a 46-year-old rider from Harrisonburg, Va., was thrown from his Harley-Davidson moments after hitting a deer in the middle of the road, state police said.

In May, a 55-year-old motorcyclist was killed after a deer dashed across Route 460 in Bedford County, Va., state police said.

In September 2011, a Maryland motorcyclist was killed and his passenger was critically injured when a deer that jumped into the road in Glen Burnie caused a three-vehicle crash.

In August 2011, a 50-year-old Arlington County motorcyclist died after his Harley collided with a deer on Compton Road near Balmoral Forest Road in Fairfax County, county police said.

In August 2011, a 48-year-old motorcyclist was killed and his 55-year-old passenger was injured when they hit a deer on eastbound on Route 702.

In April 2011, a 37-year-old motorcyclist from West Ocean City was killed when his motorcycle hit a deer in Bishopville, Md., state police said.

In May 2010, a 54-year-old Frederick County man died after his motorcycle struck a deer in Clarke County, according to Virginia State Police.